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28

Issue 1

2007

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Orginal scientific paper – Izvorni znanstveni rad

Recovering logging residue: experiences from the Italian Eastern Alps Raffaele Spinelli, Carla Nati, Natascia Magagnotti Abstract – Nacrtak Conducted within the scope of a larger Italian project, the study analyzes three recovery alternatives for logging residue and identifies the conditions that make one preferable to the others. To the purpose, the authors used spreadsheet models based on experiments, which return the delivered cost of biomass as a function of working conditions and costing assumptions. Chipping, bundling and transporting loose uncomminuted residue are all viable options, and they are indeed applied on a commercial scale in several Countries, including Italy. Transporting loose uncomminuted residue is the simplest method, which avoids investing in costly equipment. However, this system is constrained by the difficulty of fully exploiting vehicle payload: it is not suitable to the handling of fine slash, and is preferable only over short hauling distances. Chipping at the landing is technically the most effective method, but it requires close co-ordination of the transportation fleet. If truck delays exceed 40 minutes per load, then bundling becomes a better choice. Keywords: logging residue, chipping, bundling, loose transport, delivered costs

1. Introduction – Uvod In Italy, the rapid development of the bioenergy sector has boosted the biomass market: prices have increased very fast, encouraging better recovery of the existing resources and increasing imports of waste wood from neighbouring Countries. Logging residue represents an important wood source that can be exploited for energy purposes: hence the interest for new technologies that can reduce the cost of recovery and increase the share of logging residue within economic reach. There is a general interest to streamline the recovery of logging residue, which demands specific knowledge. This is particularly important for the Alps and temperate Europe in general, since much of the knowledge currently available has been generated in the Nordic Countries, under very different work conditions (Cuchet et al. 2004). Logging residue originates from tree processing into traditional assortments, such as sawlogs and pulpwood. Processing can be conducted at the stump or at the landing, if whole trees are extracted. The latter case offers the advantage of concentrating residue, thus making recovery easier. On the other Croatian Journal of Forest Engineering 28(2007)1

hand, residue left at the stump can always be collected and forwarded to a landing after processing. If terrain is too steep or too soft for heavy machine traffic, then the residue must always be made available at a landing – regardless of where processing takes place. The study considers residue already available at a landing – whether because trees have been processed there, or because the residue has been forwarded after processing in the stand. Under such conditions, recovery can be conducted according to one of the following three systems: Þ 1 – chipping at landing (Fig.1) and transporting the chips to the plant (Spinelli and Hartsough 2001); Þ 2 – bundling at the landing (Fig. 2), transporting the bundles (Andersson 1999) to the plant and chipping them there just before consumption; Þ 3 – transporting loose uncomminuted residue (Fig. 3) to the plant and chipping it there just before consumption (Ranta and Rinne 2006). The goal of this study is to analyze these three recovery alternatives and to identify the conditions that make one preferable to the others. This way,

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R. SPINELLI et al.

Recovering logging residue: experiences from the Italian Eastern Alps (1–9)

Fig. 1 Chipping residue at landing Slika 1. Iveranje na pomo}nom stovari{tu

Fig. 2 Bundling at landing Slika 2. Izradba sve`njeva na pomo}nom stovari{tu managers can decide what harvesting method is best applied under their own specific work conditions. In particular, the study aims at providing: a) a

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break-even transport distance beyond which transporting loose uncomminuted slash becomes more expensive than transporting chips or bundles and b) Croatian Journal of Forest Engineering 28(2007)1


Recovering logging residue: experiences from the Italian Eastern Alps (1–9)

R. SPINELLI et al.

Fig. 3 Loading uncomminuted tops Slika 3. Utovar neusitnjenih ovr{ina the amount of interaction delay that can be accepted in chipping operations before bundling becomes a less expensive option.

2. Reseach Approach – Istra`iva~ki pristup Data used for the comparison refer to a Jenz HEM 560D truck-mounted chipper, equipped with a 335 kW independent engine and a hydraulic loader for chipper feeding, and to a Timberjack 1490D truck-mounted slash bundler, also equipped with a hydraulic feeding loader. As to the third option – i.e. the transportation of loose uncomminuted residue, the model refers to a truck-and-trailer unit with special enlarged load bays and hydraulic loader. All the three operations were studied in detail, accurately measuring work time, delay time, delivered tonnage and transportation distance (Spinelli et al. 2006a). Since the goal of the study is to know when one of the three systems is preferable to the others, the three systems have been modelled through statistical analyses (SAS 1999), and the models have been used to conduct a simulation aimed at comparing system performance under varying work conditions. Before analysing the results of this simulation – however – it is best to set some reference points, in order to better understand the different processes Croatian Journal of Forest Engineering 28(2007)1

and to avoid errors in the interpretation and application of the results. Þ 1 – transporting bundles or loose uncomminuted slash all the way to the plant is only advisable when the plant is equipped with a high-output stationary chipper (Fig.4). Using such machine results in a dramatic reduction of chipping cost, which partly offsets the higher cost of transporting loose residue or the additional cost of bundling (Spinelli and Magagnotti 2005); Þ 2 – transporting loose uncomminuted residue has already been applied with some success both in Austria and in Finland (Ranta and Rinne 2006). In Italy this system is used on a commercial scale by some contractors in the Italian Northeast (Spinelli et al. 2006 b). However, the procedure can only be applied to an appropriate mix of tops, discarded logs and fine slash: it is unlikely that it can give favourable results when used for fine slash only, which aggravates the main drawback of loose slash transportation – i.e. the very low bulk density and the consequent difficulty of fully exploiting vehicle payload (Rawlings et al. 2004). For the same reasons, the profitability of transporting loose slash drops very quickly with transportation distance, and the system

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Recovering logging residue: experiences from the Italian Eastern Alps (1–9)

is only suitable to short hauls. In general, the advantage of transporting loose residue is the dramatic reduction of the investments in dedicated machinery – such as a mobile chipper or a bundler, which may cost between 300,000 and 400,000 ; Þ 3 – bundling has two main limits: first of all, it represents an additional processing step, and secondly it runs at a much slower pace compared to chipping. In fact, a bundler hourly cost is almost the same of a chipper with almost twice its productivity. The main advantage of bundling is logistics: while chippers generally need a truck by the side to receive the chips they expel from their spouts, bundlers are completely independent, as they can stack the bundles on the ground for later collection by transportation units (Johansson et al. 2006). This prevents any problems with co-ordinating the chipper and the truck fleet, which may cause considerable delays – possibly offsetting the productivity edge of the chipper. Joint chipper and truck operation also requires larger landings, which can accommodate a chipper and a truck at the same time. On the contrary, a bundler can be used on smaller landings, since the transport vehicle can move in after the bundler has finish-

ed with its job. Therefore, comparison between the chipper and the bundler boils down to identifying the »disorganization threshold« acceptable for the chipping operation, before its productive edge is totally eroded and bundling becomes a cheaper option.

3. Results – Rezultati Simulation was based on the experimental data shown in Tables 1 and 2, respectively for slash processing (chipping or bundling) and transport: these data were recorded on well-organized operations, as shown by the very limited incidence of delays. Experimental data were compatible with the figures obtained by other authors for similar machines: in particular, the performance recorded for the truckmounted bundler in Italy was very similar to that obtained with the same machine in other studies conducted in Austria (Kanzian 2005) and Germany (Wittkopf 2004). The tables refer both time consumption and machine productivity to the oven-dry tonne (odt) in order to provide unambiguous reference. As to chipping at the plant, data collection highlighted the high productivity of stationary chippers, which reached 16.7 oven-dry tonnes/hour with bundles and 14.4 oven-dry tonnes/hour with slash.

Fig. 4 Stationary chipper Slika 4. Stacionirani ivera~ 4

Croatian Journal of Forest Engineering 28(2007)1


R. SPINELLI et al.

Recovering logging residue: experiences from the Italian Eastern Alps (1–9)

Table 1 Productivity of chipping and bundling Tablica 1. Proizvodnost iveranja i izradbe sve`njeva Process Radni postupak Work, min/odt Rad, min/odt Other, min/odt Ostalo, min/odt Delay, min/odt Prekid, min/odt Delay, % of total time Prekid, % od ukupnoga vremena Productivity, odt/h Proizvodnost, odt/h odt – oven-dry tonne – masa suhe tvari, t

Table 2 Productivity of transportation Tablica 2. Proizvodnost prijevoza

Chipping Iveranje

Bundling Izradba sve`njeva

7.5

10.0

0.5

2.4

1.0

0.9

10.8

6.8

6.7

4.5

Source – Izvor: Spinelli et al. (2006)

Operation cost was estimated with the usual accounting methods adapted to forestry (Miyata 1980). We assumed an initial investment of 320,000  for the truck-mounted chipper, 400,000  for the truck-mounted bundler, 110,000  for each truck and 130,000  for each truck-and-trailer unit. These amounts were depreciated over 8 years to a salvage value of 20%. The annual utilization was set to 1000 hours, assuming a professional use. Transportation units make exception, as they are generally used more intensively: therefore we assumed a depreciation over 5 years and an annual utilization of 1800 hours. Labour cost was set to 18 /hour, interest rate to 4% and fuel cost to 1.1 /litre. The raw costs thus obtained were increased by 25%, to account for profit and overheads. The hourly operating costs are then 165  for the mobile chipper, 159  for the bundler, 59  for the truck and 70  for the truck and trailer combination. When loose uncomminuted slash is transported, we have included the cost of a second operator to assist the loading, as tops often need some trimming: this work could be done by the loader operator if the grapple was equipped with a hydraulic saw – however, no such arrangement was observed during our studies and we preferred to avoid extrapolation of data. The cost of the loading assistant was estimated to 18 /hour and charged on the loading time only, not on the whole cycle. The operating cost of the stationary chipper was calculated on different assumptions, closer to the economical environment of large industry such as: utilization of 4800 hours/year, depreciation on 8 years and electricity cost of 0.08 /kWh. Results were checked with the assistance of the plant managers and indicate a chipper cost of 130 /hour. Croatian Journal of Forest Engineering 28(2007)1

Product – Proizvod Chips Bundles Slash Iverje Sve`njevi Granjevina Truck – Kamion Load, odt 6.3 5.9 Tovar, odt Travel on forest road, km/h 14 14 Vo`nja po {umskoj cesti, km/h Travel on country road, km/h 30 30 Vo`nja po lokalnoj cesti, km/h Travel on state road, km/h 52 52 Vo`nja po dr`avnoj cesti, km/h Load, min/trip 50.3 20.7 Utovar, min/tura Weight and Unload, min/trip 8.4 21.6 Vaganje i istovar, min/tura Delay, min/trip 8.1 8.1 Prekid, min/tura Truck-and-trailer – Kamionski skup Load, odt 16.0 15.0 Tovar, odt Travel on forest road, km/h 14 14 Vo`nja po {umskoj cesti, km/h Travel on country road, km/h 21 21 Vo`nja po lokalnoj cesti, km/h Travel on State road, km/h 50 50 Vo`nja po dr`avnoj cesti, km/h Load, min/trip 127.7 52.6 Utovar, min/tura Weight and Unload, min/trip 21.0 48.3 Vaganje i istovar, min/tura Delay, min/trip 10.1 10.1 Prekid, min/tura

3.5 14 30 52 17 10.8 8.1

9.6 14 21 50 117.0 18.7 10.1

Source – Izvor: Spinelli et al. (2006)

Data shown above were assembled in a worksheet and used to calculate: Þ the maximum distance within which transporting loose uncomminuted slash is less expensive than transporting chips or bundles; Þ the amount of chipping delay that can be accepted before bundling becomes a less expensive option. These simulations were conducted for two different cases, and namely: 1) landing size and road standard allow using truck-and-trailer units for trans-

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Recovering logging residue: experiences from the Italian Eastern Alps (1–9)

Fig. 5 Relationship between delivered cost and transport distance (truck option) Slika 5. Ovisnost tro{kova dobave o udaljenosti prijevoza kamionom portation, and 2) landing size and/or road standards force resorting to trucks for transportation. Figures 5 and 6 show the relationship between delivered cost and transportation distance for the three alternatives: figure 5 refers to truck transportation, whereas figure 6 is based on the use of truckand-trailer units. In both cases, we assumed that the operations are well organized and that the chipper normally waits 5 minutes between the departure of a transport unit and the arrival of the next one. In both cases, bundling proves to be the least efficient option: on the contrary, transporting loose uncomminuted residue emerges as the cheapest alternative, when transportation distance does not exceed 40 km. Of course, this is only true for relatively large-sized slash: it is very difficult to assemble a significant load with fine slash, after taking away the tops and all the stemwood with a diameter above 10–12 cm. The operations observed were indeed conducted on residue obtained after delimbing trees and topping them to a diameter of 18–20 cm. Although the chipping chain is much cheaper than the bundling chain, the former is very sensitive to organizational problems: a chipper can work effectively only if a truck is placed by its side to receive the chips, and it is not always easy to guarantee a good co-ordination of the chipper and the truck fleet. Therefore, chipper work can be slowed down by recurring waiting delays, which can be considered normal and acceptable if their incidence is contained

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Fig. 6 Relationship between delivered cost and transport distance (truck-trailer option) Slika 6. Ovisnost tro{kova dobave o udaljenosti prijevoza kamionskim skupom

Fig. 7 Delivered cost of chips as a function of chipper waiting time between loads Slika 7. Ovisnost tro{kova dobave o vremenu prekida rada ivera~a – ~ekanje izme|u tovara

within certain limits. In our previous simulation runs, we have assumed an average delay between trucks of 5 minutes, which is certainly acceptable: as delays grow increasingly long, chipping cost becomes higher, and at a certain point it will reach the same value Croatian Journal of Forest Engineering 28(2007)1


Recovering logging residue: experiences from the Italian Eastern Alps (1–9)

as bundling cost. Beyond that figure, bundling becomes a preferable option. Figure 7 shows the results of a simulation conducted for increasing chipper waiting time, assuming a transportation distance of 35 km, 2 of which on forest roads, 10 on country roads and the remaining 13 on state roads. If transportation is performed by trucks, chipping is preferable to bundling until the average waiting time between the departure of a truck and the arrival of the next one is below 40 minutes (Fig. 7). When truck-and-trailer units are used, the chipper can afford an average waiting delay of almost an hour and a half, before bundling becomes a better alternative. Finally, there is a third possibility, namely that the landing is too narrow for accommodating a chipper and a truck-and-trailer unit at the same time, but it can indeed accept the truck-and-trailer if the chipper was not there: in such instance, bundling would allow upgrading to the more efficient transportation unit, whereas chipping forces resorting to simpler, less efficient trucks. If this is the case, chipping is preferable only if waiting delays can be contained within the average value of 20 minutes per load (Fig. 7).

4. Conclusions – Zaklju~ak Chipping, bundling and transporting loose uncomminuted residue are all viable options, and they are indeed applied on a commercial scale in several Countries, including Italy. Each alternative has its advantages and drawbacks, which must be carefully evaluated in order to make the choice that is most appropriate to the specific situation. Transporting loose uncomminuted residue is the simplest method, which avoids investing in costly equipment. However, this system is constrained by the difficulty of fully exploiting vehicle payload and it is not suitable to the handling of fine slash. Chipping at the landing is technically the most effective method, but it requires close co-ordination of the transportation fleet. The number of units assigned to the operation must reflect both chipper capacity and transportation distance: excessive waiting erodes the productive edge of chipping at landing, and favours the other two methods. Bundling represent an additional process and therefore increases the total cost of recovery: however, it has the advantage of independent operation and prevents much of the organizational problems related to chipping at forest landings. If local logging companies are not organised well enough to guarantee close operational co-ordination, bundling becomes a better alternative – especially if the slash is fine, Croatian Journal of Forest Engineering 28(2007)1

R. SPINELLI et al.

which excludes transportation of loose uncomminuted residue. The simulations conducted here show that bundling is preferable to chipping when the average waiting time for the chipper reaches 40 minutes per truck, or a hour and a half per truck-and-trailer unit. If bundling also allows transportation on a truck-andtrailer unit rather than on a truck, chipping at the landing must be preferred only if the average waiting time per truck is not longer than 20 minutes. Of course, such results depend on the specific costing assumptions previously described: different conclusions could be reached under other assumptions, such as a less intensive utilization of the machinery, the release of public subsidies or the availability of labour at marginal costs. For this reason, readers are encouraged to request and use the above-mentioned free worksheet to calculate a personalised recovery cost and to compare options under user-specified conditions.

Acknowledgements – Zahvala Since 2003, CNR has initiated a new project on the cost-effective production of forest chips in the Alpine forests of Northeastern Italy. The project has received the sponsorship of 14 different organizations, including the Regional Forest Services of Trentino, Veneto and Friuli Venezia Giulia, as well as the main forest owners’ Associations of the area. Twenty field tests were conducted on a variety of stands and conditions, leading to the production of several spreadsheet models. Overall results have been summarized in a book of »Guidelines for the development of forest chip supply chains«, also available in English. The electronic version of the book can be requested to the corresponding Author at: spinelli@ivalsa.cnr.it

5. References – Literatura Andersson, G., 1999: New technique for forest residue handling. Proceedings of the Forest Engineering International Conference, Edinburgh, 28–30 June 1999, 6 pp. Cuchet, E., Roux, P., Spinelli, R., 2004: Performance of a logging residue bundler in the temperate forests of France. Biomass and Bioenergy, 27: 31–39. Johansson, J., Liss, J., Gullberg, T., Bjorheden, R., 2006: Transport and handling of forest energy bundles – advantages and problems. Biomass and Bioenergy, 30(4): 334–341. Kanzian, C., 2005: Bereitstellung von Waldhackgut: Verfahren Energieholzbündeln im Gebirge. Universität für Bodenkultur Wien, Department für Wal- und Boden- Wissenschaft, 36 pp.

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Recovering logging residue: experiences from the Italian Eastern Alps (1–9)

Miyata, E. S., 1980: Determining fixed and operating costs of logging equipment. General Technical Report NC-55. Forest Service North Central Forest Experiment Station, St. Paul, MN. 14 pp. Ranta, T, Rinne, S., 2006: The profitability of transporting uncomminuted raw materials in Finland. Biomass and Bioenergy, 30(3): 231–237. Rawlings, C., Rummer, B., Seeley, C., Thomas, C., Morrison, D., Han, H., Cheff, L., Atkins, D., Graham, D., Windell, K., 2004: A study of how to decrease the costs of collecting, processing and Transporting Slash. Montana Community Development Corporation. Missoula (MT), 21 pp. SAS Institute Inc. 1999. StatView Reference. SAS Publishing, Cary, NC. p. 84–93, ISBN-1-58025-162-5.

Spinelli, R., Hartsough, B., 2001: A survey of Italian chipping operations. CNR-IRL Contributi Scientifico-Pratici XLI, Firenze, 112 p. Spinelli R., Magagnotti, N., 2005: Recupero di biomassa residua nel taglio a gruppi in fustaia Alpina. Dendronatura, 2: 49–60. Spinelli, R., Nati, C., Magagnotti, N., 2006: Recupero di biomassa: alcune utilizzazioni di boschi Alpini. Sherwood, 119: 1–7. Spinelli, R., Magagnotti, N., Nati, C., Aguanno, M., 2006b: Produzione di biomassa dalla gestione delle peccete artificiali alpine. Dendronatura, 1: 23–30. Wittkopf, S., 2004: Einsatz der Bündelmaschine Fiberpac. LWF Aktuell, 48: 24–26.

Sa`etak

Iskori{tavanje drvnoga ostatka pri sje~i i izradbi – iskustvo iz talijanskih isto~nih Alpa Ubrzani je razvoj uporabe obnovljivih izvora energije u Italiji utjecao na tr`i{te proizvoda biomase pove}avaju}i cijene proizvoda, iskoristivost postoje}ih izvora biomase te uvoza drvnih ostataka iz susjednih zemalja. Drvni ostatak nastaje kao nusproizvod sje~e i izradbe, a predstavlja va`an izvor drvne sirovine koji se mo`e iskoristiti u energetske svrhe. Primjenom sortimentne metode izradba se obavlja u sje~ini kod panja te se drvni ostatak treba skupiti i privu}i na pomo}no stovari{te. Kod stablovne metode izradba se obavlja na pomo}nom stovari{tu pri ~emu se drvni ostatak gomila na jednom mjestu, {to olak{ava njegovo iskori{tavanje. U radu se pretpostavlja da je drvni ostatak dostupan na pomo}nom stovari{tu bilo zbog izvo|enja izradbe stabala na stovari{tu ili zbog privla~enja drvnih ostataka nakon izradbe u sje~ini. Pri tome }e se razmatrati tri postupka pri iskori{tavanju drvnoga ostatka: Þ iveranje na pomo}nom stovari{tu i prijevoz iverja do energane Þ izradba sve`njeva od drvnoga ostatka na pomo}nom stovari{tu te prijevoz sve`njeva i njihovo iveranje u energani Þ prijevoz neusitnjenoga drvnoga ostataka (granjevine) i iveranje u energani. Cilj je rada da se utvrdi udaljenost pri kojoj je prijevoz neusitnjenoga drvnoga ostatka skuplji od prijevoza iverja ili sve`njeva te udio prekida rada do kojega je iveranje tro{kovno prihvatljivije od izradbe sve`njeva. Za usporedbu su kori{tena ova sredstva: Þ na kamionu postavljen ivera~ Jenz HEM 560D snage motora 335 kW, opremljen hidrauli~nom dizalicom Þ na kamionu postavljen bandler Timberjack 1490D, opremljen hidrauli~nom dizalicom Þ kamionski skup (kamion s prikolicom) opremljen hidrauli~nom dizalicom te pove}anim tovarnim prostorom za prijevoz neusitnjenoga drvnoga ostatka. Istra`ivanje razli~itih na~ina iskori{tavanja drvnoga ostatka provedeno je studijem rada i vremena, mjerenjem isporu~ene te`ine drvnoga ostatka te prije|enim udaljenostima prijevoza. Svi su postupci modelirani statisti~kom ra{~lambom te uspore|eni radi odre|ivanja najisplativijega postupka pri razli~itim uvjetima rada. Pri tome je potrebno naglasiti odre|ene zna~ajke tih postupaka. Za prijevoz sve`njeva i neusitnjenoga drvnoga ostatka energana mora biti opremljena visoko u~inkovitim stacioniranim ivera~em. Prijevoz neuistnjenoga drvnoga ostatka mo`e se primijeniti jedino u slu~aju velikoga udjela sitne granjevine koja omogu}uje ve}u gusto}u tovara, tj. bolju iskori{tenost nosivosti vozila. Izradba je sve`njeva dodatni postupak u procesu proizvodnje, a satni tro{ak bandlera jednak je tro{ku ivera~a s dvostruko ve}om proizvodnosti. No, rad ivera~a zahtijeva kamion na mjestu

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Croatian Journal of Forest Engineering 28(2007)1


Recovering logging residue: experiences from the Italian Eastern Alps (1–9)

R. SPINELLI et al.

rada za prihvat iverja i time prostrana stovari{ta. Tako|er je potrebna dobra organizacija rada ivera~a i kamiona za prijevoz iverja kako bi se izbjegli dulji prekidi rada. Bandler je neovisan o kamionu te mo`e slagati sve`njeve u slo`ajeve ~ime se olak{ava i ubrzava kamionski utovar. Uporedba postupaka pri iskori{tavanju drvnoga ostatka provedena je na podacima prikazanima u tablicama 1 i 2 dobivenima prija{njim istra`ivanjima. U~inak stacioniranoga ivera~a u energani iznosi 16,7 tona suhe tvari na sat pri iveranju sve`njeva, odnosno 14,4 tone suhe tvari na sat pri iveranju granjevine. Za izra~un tro{kova rada pretpostavljeni su i odre|eni ovi parametri: po~etna ulaganja od 320 000  za ivera~, 400 000  za bandler, 110 000  za svaki kamion, 130 000  za kamionski skup, vrijeme amortizacije ivera~a i bandlera 8 godina uz godi{nju iskoristivost od 1000 pogonskih sati, vrijeme amortizacije prijevoznih sredstava 5 godina uz godi{nju iskoristivost od 1800 pogonskih sati, tro{ak radnika 18 /h, kamatna stopa 4 %, tro{ak goriva 1,1 /L. Izra~unati tro{ak rada iznosi 165 /h za ivera~, 159 /h za bandler, 59 /h za kamion i 70 /h za kamionski skup. Za stacionirani ivera~ u energani tro{ak rada iznosi 130 /h uz odre|eno vrijeme amortizacije od 8 godina, godi{nju iskoristivost od 4800 pogonskih sati te tro{ak elektri~ne energije 0,08 /kWh. Na slikama 5 i 6 prikazane su ovisnosti jedini~nih tro{kova o udaljenosti prijevoza kamionom i kamionskim skupom za sve tri ina~ice. U oba slu~aja pretpostavljen je prekid rada ivera~a na stovari{tu od 5 minuta zbog ~ekanja prijevoznoga sredstva. Izradba i prijevoz sve`njeva pokazuju se najskupljom opcijom, dok je prijevoz neuistnjenoga drvnoga ostatka najisplativiji na udaljenosti do 40 km. Slika 7 prikazuje rezultate ovisnosti jedini~nih tro{kova o pove}anju prekida rada ivera~a zbog ~ekanja prijevoznoga sredstva pri udaljenosti od 35 km, od toga 2 km na {umskoj cesti, 10 km na lokalnoj cesti i 13 km na dr`avnoj cesti. Kod prijevoza kamionima iveranje je povoljnije od izradbe sve`njeva ako su prekidi rada ivera~a manji od 40 minuta. Kod prijevoza kamionskim skupovima tek kad su prekidi rada ivera~a ve}i od sat i 30 minuta, izradba sve`njeva postaje tro{kovno povoljnija. U slu~aju manje prostranoga stovari{ta na kojem se ne mo`e uz ivera~ smjestiti kamionski skup ve} jedino kamion, izradba je sve`njeva tro{kovno isplativija kada prekidi rada ivera~a zbog ~ekanja kamiona prema{e 20 minuta po tovaru. Iz rezultata se zaklju~uje da je prijevoz neusitnjenoga drvnoga ostatka najjednostavnija metoda kojom se izbjegava nabava skupih sredstva, ali se javlja problem nedovoljne nosive iskoristivosti prijevoznoga sredstva. Iveranje je na pomo}nom stovari{tu naju~inkovitija metoda, ali zahtijeva vrlo dobru organizaciju prijevoznih sredstava. Pove}anjem prekida rada ivera~a zbog ~ekanja prijevoznoga sredstva smanjuje se proizvodnost ivera~a te se pridonosi opravdanosti primjene drugih dvaju postupaka. Izradba sve`njeva pove}ava ukupni tro{ak proizvodnoga procesa, ali je tehnolo{ko rje{enje neovisno o organizacijskim problemima. Klju~ne rije~i: {umski ostatak, iveranje, izradba sve`njeva, prijevoz granjevine, tro{kovi dobave

Authors’ address – Adresa autorâ:

Received (Primljeno): October 3, 2006 Accepted (Prihva}eno): January 18, 2007 Croatian Journal of Forest Engineering 28(2007)1

Raffaele Spinelli, PhD e-mail: spinelli@ivalsa.cnr.it Carla Nati, PhD. e-mail: nati@ivalsa.cnr.it Natascia Magagnotti, BSc. e-mail: magagnoti@ivalsa.cnr.it CNR/IVALSA Via Madonna del Piano – Palazzo F I-50019 Sesto Fiorentino (FI) ITALY

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Orginal scientific paper – Izvorni znanstveni rad

Morphological characteristics and productivity of skidder ECOTRAC 120V Dubravko Horvat, @eljko Ze~i}, Marijan [u{njar Abstract – Nacrtak This paper presents the results of morphological analysis of the Croatian skidder ECOTRAC 120V, as well as the research of its productivity features in timber skidding from hilly terrain after preparatory felling and from mountainous terrain after selective felling. Morphological analysis was used for determining the dependence of morphological features of the skidder ECOTRAC 120V, as well as for establishing its belonging to the skidder’s family. The characteristics of the researched skidder are small width relative to length, due to the requirements of its manoeuvrability in timber skidding on skid roads of up to 2.5 m in width, and higher engine power relative to skidder mass. Such considerations give justification for morphological analyses, because they provide the possibility of observing development trends of machines, as well as ways of finding the right design solutions for meeting the requirements for their use. The comparison of two working sites in the research of productivity of skidders clearly shows that productivity primarily depends on harvesting density (working time at the felling site) and skidding speed, and that in this case a considerable difference in the size of the load is not a key factor of productivity in timber skidding. Keywords: skidder ECOTRAC 120V, morphological analysis, timber skidding, daily output, unit cost

1. Introduction – Uvod In hilly and mountain forests of Croatia, wheeled skidders equipped with winch are the most commonly used vehicles for timber skidding after preparatory and selective felling. Similarity between preparatory and selective fellings in hilly and mountain forests lies in approximately the same size of trees, so that the same methods and similar techniques may be applied in skidding the processed timber assortments. Based on the analysis of the annual allowable cut of the Croatian forestry by type of felling and terrain conditions, Krpan et al. (2003) determined the quantity of 1.4 mil. m3 of timber assortments skidded by large skidders after preparatory and selective fellings in hilly and mountain forests. Nowadays in Croatia, approximately 300 skidders owned by the company »Hrvatske {ume« d.o.o. Zagreb, and about 100 skidders (rough estimate) owned by private contractors are in use. More than 100 of them are thinning skidders, with a mass lower than 4 t, which have been designed and manufacturCroatian Journal of Forest Engineering 28(2007)1

ed in Croatia. The remaining 300 skidders of a mass of more than 7 t have been imported and they are used for skidding timber of larger size after final felling. Based on the requirements of the Croatian forestry for such technology of timber skidding, and taking into consideration the current number of such skidders as well as the production possibilities of the factory »Hittner« d.o.o., the idea arose to develop a domestic skidder of a mass of more than 7 tons. Within the development project of the Ministry of Science, Education and Sports, the project of design and manufacture of the new skidder includes the manufacturer as well as forestry experts and scientists working at the Faculty of Forestry, whose task is to establish the basic technical and technological requirements for the skidder’s construction using their knowledge and experience. The basic idea is that the newly produced skidder should fully meet the requirements for timber skidding in the Croatian forests. The objective of this paper is to establish belonging of the new skidder to the skidder’s family by

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Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

axle and 41% at the rear axle). The maximum allowable mass at the skidder’s rear axle is 6000 kg. The skidder has a diesel engine, of a nominal power of 84 kW. It is equipped with a double-drum winch of the nominal tractive force of 80 kN. The pulling cable is 14 mm in diameter, and 70 m long per each drum. The winch is driven hydraulically, and steering is electro-hydraulic. The rear blade is used for receiving, protecting and anchoring purposes and it can be raised and lowered by two hydraulic cylinders.

3. Research methods – Metode istra`ivanja Fig. 1 Skidder ECOTRAC 120V Slika 1. Skider ECOTRAC 120V morphological analysis of the basic dimensions and to determine its productivity by work and time study at two characteristic working sites in timber skidding after preparatory and selective felling.

2. Skidder ECOTRAC 120V – Skider ECOTRAC 120V The basic dimensions and mass distribution of the skidder ECOTRAC 120V are shown in Figure 2 (Horvat and [u{njar 2005). The skidder mass together with the driver is 7257 kg (59% at the front

Morphological analysis is used for establishing the current state, characteristics and patterns of forest machines as well as their possible development trends. On the basis of the selected geometric, mass and other values, dependences are expressed and judgement is made of the suitableness of the machine choice. The results of the analyses are used by forestry experts in selecting new machines, in establishing the most favourable use of machines under different work conditions and in determining parameters required for constructing new machines. Bekker (1956) carried out one of the first morphological analyses of off-road vehicles by expressing his opinion that an object moving in a medium will acquire the form that will offer the lowest possible resistance to such movement. Therefore, the mor-

Fig. 2 Dimensions and mass distribution of the skidder ECOTRAC 120V Slika 2. Dimenzije i raspored mase skidera ECOTRAC 120V 12

Croatian Journal of Forest Engineering 28(2007)1


Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

phological analysis may also be used for assessing the future development and not only for expressing the achieved levels of dimensional development of a vehicle or for trying to estimate the position of a specific vehicle in a group of similar ones. By using morphological analysis, Sever (1980) compared forest skidders equipped with winch with adapted farm tractors, establishing undoubtedly that skidders could be classified in a separate group/ family of vehicles with specific morphological characteristics. In performing the project task related to medium skidder, Sever and Horvat (1985) used the results of morphological analysis. The same authors (1992B) analysed the basic morphological characteristics of different forest vehicles. They expressed their opinion that such data could be used by designers in designing vehicles and by forestry experts in making their choice. The whole idea of this analysis is based on correlation dependence between individual pairs of morphological characteristics of skidders and on comparison of the position of ECOTRAC 120V within the whole family (group) of skidders. Known databases were used for the purpose of morpho-

Table 1. Working site characteristics Tablica 1. Zna~ajke radili{ta Forest Office [umarija Type of felling Vrsta sje~e Terrain Teren Above sea level, m Nadmorska visina, m Skid road slope Nagib vlaka Soil condition Stanje tla Tree species Vrsta drva Average tree volume, m3 Prosje~ni obujam stabla, m3 Harvesting density, m3/ha Sje~na gusto}a, m3/ha Method of timber processing Metoda izradbe drva Average skidding distance, m Srednja udaljenost privla~enja, m

\ur|evac

Senj

Preparatory felling Pripremni sijek

Selective felling Preborni sijek

Hilly – Brdovit

Mountain – Planinski

185–245

960–1155

+4%

–9.6%

Humid – Vla`no

Humid – Vla`no

Oak – Hrast (4,3%) Beech – Bukva (84.3%) Beech – Bukva (35.1%) Other – OTL (60.6%) Fir – Jela (15.7%) 0.52

1.59

128.11

46.05

Cut to length Sortimentna

Half-tree Poludeblovna

257

335

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D. HORVAT et al.

logical analysis (Sever and Horvat 1992A, Sever and Horvat 1992B, Sever and Horvat 1997, Horvat et al. 2002), and they were later up-dated with data obtained from databases of characteristics of forest machines compiled by the Department of Forest Engineering at the Institute of Forestry under the Austrian Ministry of Agriculture and Forestry (FBVA 2003). The database contains a total of 91 types of skidders. Nine morphological characteristics of skidders were selected from the database, out of which five were the basic characteristics (length L, width B, height to cabin roof HC, mass m, engine power P) and three were calculated characteristics (form indexes HC/L and W/L, unit mass gm). If the vehicle is presented in the form of a prism, then the ratios H/L (height/length) and B/L (width/length) express significant volume characteristics and they are called form indexes. Form indexes are the most important characteristics for the vehicles belonging to the same family, and they are used for describing them and as initial information on the researched vehicle and its classification into an already known family of vehicles. The data are presented in tables in a computer database, so that they can be easily accessible for determining possible dependences. Correlation dependences between certain morphological characteristics of skidder were determined with the use of the software programme REG.EXE (Hitrec and Horvat 1987). In the presentations of dependences between morphological characteristics, skidders are divided into two basic categories with respect to mass: medium skidders (mass up to 5000 kg) and skidders of a mass exceeding 5000 kg. The said division of skidders based on mass was laid out by Horvat and Sever (1995), and Horvat (1996). In timber skidding by the skidder ECOTRAC 120V at two working sites, time consumptions of work operations were measured by snap-back chronometry method, and work and time study of the skidder were carried out. Standard measuring equipment was used. Supporting measuring and description information were collected by adequate methods. Mathematical/statistical processing of data was carried out by standard PC packages, and processing of data by software programme Statistica 7.

4. Research working sites – Istra`ivana radili{ta The research of productivity was carried out at two working sites: in the area of the Forest Office of \ur|evac, forest management unit »\ur|eva~ka Bilogora«, compartment 64a, and in the area of the

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Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

Forest Office of Senj, forest management unit »Senjsko bilo«, compartment 24a. The phases of felling/ processing of trees and timber skidding at the working sites are separated in time. The data presented in Table 1 show the diversity of stand, relief and technological characteristics of the working sites. Preparatory felling was carried out at the working site of the Forest Office of \ur|evac, while selective felling was carried out at the working site of Senj in a stand with a predominant share of beech trees. In skidding timber, skidders travelled on skid roads.

5. Research results – Rezultati istra`ivanja 5.1 Morphological analysis – Morfolo{ka ra{~lamba By use of morphological analysis, dependences were determined between individual morphological characteristics of the skidder ECOTRAC 120V, and its family was established as well as its position within the whole family (group) of skidders. Figure 3 shows the relationship between form indexes of the skidder family. It can be seen that most values of form indexes are under the line H = B, i.e. they are in the area where height prevails over width of the vehicle. It is generally characteristic of tractors used for skidding/forwarding timber (adapted farm tractors, skidders with winch, forwarders) to have form indexes located in the area under the line H = B. This characteristic is the result of the requirement for extremely good manoeuvrability during work in forest stands. Vehicles of smaller width enable easier access to processed timber assortments and cause lower disturbance of forest soil and less damage to standing trees. The group of medium skidders is shifting right in the direction of higher vehicles relative to their length. The relationship between form indexes of the skidder ECOTRAC 120V is located at the very edge of the skidder field and its characteristic is a suitably small width of the vehicle relative to its length. The reason of its position is based on the requirements of the forestry profession in designing this skidder. Skid roads in hilly and mountainous regions of Croatia are intended for tractors for timber skidding of an overall width of up to 2.5 m (Pi~man and Pentek 2003), and hence in designing the skidder, attention was focused on meeting the requirements of the forestry profession so as to fit the dimensions of the skidder into given widths of the built skid roads. Total width of the skidder is 2230 mm, and together with its total length of 5930 mm, it results in a low form index B/L (width/length) of 0.38.

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Fig. 3 Form index Slika 3. Indeksi oblika The skidder mass is considered a significant morphological characteristic. Although higher mass is considered unfavourable as a rule, with skidders and other vehicles designed for skidding timber, mass has a broader meaning in terms of exploitation, because in timber skidding together with a part of mass of the skidded load it makes the effect of adhesive load and thus enables a wheel-to-soil transfer of thrust force (Sever and Horvat 1985). On the other hand, however, higher mass of skidders is considered unfavourable due to higher rolling resistance and higher wheel pressure to soil, which causes damage to forest soil. Comparison between skidder dimensions and mass is shown in Figures 4, 5 and 6. In determining the dependence, exponential regression equations were chosen due to the fact that dimensions have a limit value (asymptotic value) determined either by legal regulations or by technological requirements. Very strong regression and correlation coefficients have been determined for the established dependences of the skidder length, width and height relative to mass. It can be seen in Figures 4 and 5 that the length increases faster than width with the increase of mass. This phenomena is explained by the said limitation of the skidder’s width imposed by the width of skid roads and requirements for vehicles as narrow as possible for the work in forest in order to reduce the threat of causing damage to standing trees. The increase of the skidder length with the increase of mass is unfavourable in terms of its manoeuvrability in Croatian Journal of Forest Engineering 28(2007)1


Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

D. HORVAT et al.

Fig. 4 Dependence of length on skidder mass Slika 4. Ovisnost duljine o masi skidera

Fig. 6 Dependence of height on skidder mass Slika 6. Ovisnost visine o masi skidera

forest stands, because higher length implies a larger turning radius of the skidder and consequently its lower mobility. However, the unfavourable trend of increase of the skidder length with the increase of mass may be moderated to a certain extent by articulated steering, where by a centrally installed articulated joint a lower turning radius may be provided despite a relatively high distance between axles or total length.

The presented dependence shows that the researched skidder is located near the equalisation curves of the observed dependence of the skidder dimensions on mass, and hence it can be concluded that if fully belongs to the family and group of skidders. Width is under the equalisation curves, and the reason of its lower width is explained by compliance with the requirements of the forestry profession and design solutions. The skidder’s length and height are located under the equalisation curves. Larger length is caused by the construction of the front blade operated by two long-stroke hydraulic cylinders, which makes it largely movable, as well as by the construction of the rear anchoring blade. Total height is higher than the average, as it is defined as the distance from the ground to the highest point of the skidder, and with this skidder this point is the peak edge of the exhaust pipe elevated above the cabin roof so as to comply with the requirements of ISO standards for preventing the possibility of entrance of exhaust gases into the cabin. The analysis of the dependence of the driving engine power on mass is significant from the standpoint of the division of skidders as a separate family of vehicles with respect to adapted farm tractors. The ratio between the engine power and mass of the vehicle may be interpreted as the ratio of the engine power that can be carried by a vehicle mass unit. Sever (1980) came to the conclusion that the skidder mass unit was much lower than the mass unit of adapted farm tractors. The author explained the said phenomenon by the skidder construction with a

Fig. 5 Dependence of width on skidder mass Slika 5. Ovisnost {irine o masi skidera Croatian Journal of Forest Engineering 28(2007)1

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Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

Fig. 7 Dependence of engine power on skidder mass Slika 7. Ovisnost snage motora o masi skidera

Fig. 8 Dependence of unit mass on engine power Slika 8. Ovisnost jedini~ne mass o snazi motora skidera

higher safety coefficient due to more demanding work conditions in timber skidding. Similarly, work speeds of farm tractors engaged in agricultural production are higher than speeds at which timber are skidded by skidders. By the presentation of the said dependence only for the skidder family, a very strong linear dependence was established of the engine power on mass (Fig. 7). With the increase of the skidder mass, the power of the driving engine increases linearly, and consequently it can be concluded that 100 kg of skidder mass »carries« approximately 1 kW of the driving engine power. The researched skidder ECOTRAC 120V is located above the equalisation line due to the driving engine power of 84 kW, which along with the mass of 7257 kg means that a skidder mass of 100 kg carries 1.16 kW of the driving engine power, i.e. the skidder has a unit power of 11.6 kW/t and a unit mass of 86.4 kg/kW. The increased engine power is the result of the requirement of forestry experts based on the experience of many years of use of skidders in timber skidding from selective mountain stands. Further analysis of the dependence between the driving engine power and skidder mass was carried out based on an indicator known as the tractor unit mass (gm) defined as the ratio between net tractor mass (m) and driving engine power (P). With the dependence of unit mass on skidder engine power (Fig. 8), a strong non-linear correlation was established. As expected, due to the increase of the engine

power, the researched skidder had lower unit mass than the one characteristic of the group. The skidder unit masses range between 70 kg/kW and 150 kg/kW. This result of the analysis indicates the increasing trend of skidders unit masses with respect to those recorded in previous researches. Sever (1980) outlined unit masses for skidders ranging between 60 kg/kW and 85 kg/kW. This trend of installing engines of lower power in skidders can be explained as the development of a new quality typical of a specific family and their distinctive divergence from the usual rules of construction of farm tractors, from which skidders were originally developed.

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5.2 Loads – Tovari Data on loads are shown in Table 2. The average volume of the load in preparatory felling is almost half the size of an average load characteristic of selective felling (2.78 m3 versus 5.34 m3), but it averagely consists of a higher number (8 versus 5.7) smaller (0.35 m3 versus 0.93 m3) and shorter pieces (3.9 m versus 7 m). As the diameters of the skidded logs are of similar size at both felling sites, higher volume of the average load was recorded at the working site with selective felling as the result of skidding a lower number of much longer assortments.

5.3 Time consumption – Utro{ak vremena On the basis of the conducted time study, the structure of total consumed time was determined, as Croatian Journal of Forest Engineering 28(2007)1


D. HORVAT et al.

Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

Table 2 Load characteristics by working sites Tablica 2. Zna~ajke tovara po radili{tima Type of felling – Vrsta sje~e Total skidded timber, m3 – Ukupno privu~eno drvo, m3 Total number of pieces – Ukupan broj komada Total number of cycles – Ukupan broj turnusa Load volume, m3/cycle – Obujam tovara, m3/tura Number of pieces per load – Broj komada u tovaru Piece length, m – Du`ina komada, m Piece volume, m3 – Obujam komada, m3 Piece diameter, cm – Promjer komada, cm

Preparatory felling – Pripremni sijek 125.25 359 46 2.78 (0.78–4.52)* 8 (3–17)* 3.9 (2–7.8)* 0.35 (0.06–2.13)* 32(14–73)*

Selective felling – Preborni sijek 255.01 275 48 5.34 (1.63–10.36)* 5.7 (3–9)* 7 (2–13.2)* 0.93 (0.06–3.87)* 39 (13–75)*

* minimums and maximums – najmanje i najve}e opa`anje

Fig. 9 Structure of effective time consumption Slika 9. Struktura utro{enoga efektivnoga vremena

ling, a smaller share of work time is expected at the roadside landing. Despite higher speed of cable pulling out and winching, a considerable share of work time at the felling site with selective felling is the result of a greater average winching distance (21.8 m) and considerable moving of the skidder during load forming, and a relatively short time spent at the roadside landing. In the preparatory felling, the average winching distance is 10.5 m. The share of unloaded and loaded skidder travel is similar for both working sites. At the hilly working site, the unit effective time was 8.06 min/m3 with the daily output of 20.88 m3/day, and with selective felling the unit effective time was 9.88 min/m3 with the daily output of 31.88 m3/day. As the skidder worked longer (on the average 392.52 min/day) at the working site of Senj (selective felling) than at the working site of \ur|evac (preparatory felling), where the skidder worked on the average for 357.75 min/day with a much higher share of effective time, it is no wonder that the established daily output with the selective felling was higher by 11.00 m3 or 34.5%.

5.4 Allowance time – Dodatno vrijeme well as the structure of effective time and delay times. The work in skidding roundwood from a hilly working site after preparatory felling is characterised by an extremely low time efficiency (effective time is 47.06% of total time), unlike skidding from the mountain working site after selective felling (effective time is 80.2% of total time). Distribution as a component of effective time (Fig. 9) is relatively similar for both working sites. However, with selective felling a larger share of work time is spent at the felling site and a smaller at the roadside landing. Considering the fact that a smaller number of longer pieces was recorded in the load with selective felCroatian Journal of Forest Engineering 28(2007)1

The structure of allowance time is shown in Figure 10. The meal time was calculated on the basis of a 30-minute break in an 8-hour working time. Total allowance time of the skidder Ecotrac 120V at the hilly working site is 347.53 minutes (34.25% of effective time), and at the mountain working site it is 451.98 minutes, (17.95% of effective time). The factors of allowance time are 1.34 in the first case and 1.18 in the second.

5.5 Cycle time – Vrijeme turnusa Figure 11 shows the structure of modelled cycle times for the felling site and skid road travel over a

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Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

minutes, and at the mountain working site during selective felling 54.44 minutes, which is by 33.01 minutes more. Time standard at the hilly working site is 10.35 min/m3, and at the mountain working site 12.03 min/m3 (Table 3). During selective felling at the mountain working site, consumption of fixed times is high and namely 64.43% of effective cycle time (54.51% at the hilly working site), with larger shares of loading (47.15%). Thus 10.24% more time was consumed for loading at the hilly working site after preparatory felling. The share of time of unloading is smaller by 7.99% than that at the hilly working site.

Fig. 10 Structure of allowance time Slika 10. Struktura dodatnoga vremena

Fig. 12 Percentage of effective and allowance time Slika 12. Postotni udio efektivnoga i dodatnoga vremena Table 3 Modelled time standards and daily outputs of the skidder Ecotrac 120V Tablica 3. Oblikovana norma vremena i dnevni u~inak skidera Ecotrac 120V Type of felling Vrsta sje~e

Fig. 11 Structure of modelled effective time Slika 11. Struktura oblikovanoga efektivnoga vremena

distance of 300 m as well as for roadside landing travel of 50 m. The effective cycle time at the hilly working site during preparatory felling is 21.43

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Average load volume, m3 Prosje~ni obujam tovara, m3 Standard time, min/m3 Norma vremena, min/m3 Daily output, m3/day Dnevni u~inak, m3/dan

Preparatory felling (hill) Pripremni sijek (brdo)

Selective felling (mountain) Preborna sje~a (planina)

2.78

5.34

10.35

12.03

46.38

39.92

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Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

5.6 Skidder speeds, speeds of cable pulling out and winching – Brzine traktora, brzine izvla~enja u`eta i privitlavanja

road slope (a), average daily temperature (T) and load volume (q). v = a + b1 l + b2 st + b3 a + b4 T + b5 q, (min)

The speeds of loaded and unloaded skidders (loaded and unloaded travel) were calculated by use of times obtained by multiple linear regression analysis. At the hilly working site (Koprivnica), the unloaded skidder travels downhill on skid road, and the loaded skidder uphill at a slope of +4%. At the mountain working site (Senj) the situation is the other way round, the unloaded skidder travels uphill and the loaded skidder downhill at a slope of –9.6%. Table 4 shows the coefficients of equalisation equations of travel times with correlation factors. In calculating the travel time of the loaded skidder in the hilly region, the following relevant parameters were used: distance (l), soil condition (st),

The same parameters were used with the unloaded skidder except load volume. v = a + b1 l + b2 st + b3 a + b4 T, (min) In observing the travel of loaded skidders at roadside landing, the following parameters were taken into consideration: distance (l), load volume (q) and number of pieces in a load (n). v = a + b1 l + b2 q + b3 n, (min) With unloaded skidders, only the travel distance (l) was observed. v = a + b1 l, (min)

Table 4 Equation parameters of multiple linear regression analysis Tablica 4. Parametri jednad`bi multiple linearne regresijske analize Type of time Vrsta vremena 1. Felling site and skid road Sje~ina i traktorski put Unloaded skidder travel Vo`nja neoptere}enoga skidera Loaded skidder travel Vo`nja optere}enoga skidera 2. Roadside landing Pomo}no stovari{te Unloaded skidder travel Vo`nja neoptere}enoga skidera Loaded skidder travel Vo`nja optere}enoga skidera

a

Parameters – Parametri b1 b2 b3 Preparatory felling (hill) – Pripremni sijek (brdo)

b4

b5

q

l

st

a

T

–0.6773

0.0077

0.3589

–0.0120

0.0354

–4.3734

0.0185

0.7128

0.3274

–0.0443

l

q

n

0.1630

0.0083

0.2291

0.0105

R

0.95 0.1077

0.93

0.61 –0.0016

0.0110

0.60

Selective felling (mountain) – Preborna sje~a (planina) 1. Felling site and skid road Sje~ina i traktorski put Unloaded skidder travel Vo`nja neoptere}enoga skidera Loaded skidder travel Vo`nja optere}enoga skidera 2. Roadside landing Pomo}no stovari{te Unloaded skidder travel Vo`nja neoptere}enoga skidera Loaded skidder travel Vo`nja optere}enoga skidera

l

st

a

–0.9118

0.0174

0.7894

0.1620

0.5990

0.0229

–0.5145

0.1172

l

q

n

0.1289

0.0126

0.3588

0.0005

Croatian Journal of Forest Engineering 28(2007)1

q 0.95 0.3077

0.96

0.61 –0.0732

0.2233

0.12

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Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

The average travel speeds of unloaded skidders over a distance ranging between 50 m and 500 m are 5.69 km/h at the hilly working site, and 2.20 km/h at the mountain working site (Fig. 13). Loaded skidders travel at an average speed of 3.55 km/h (hilly working site) and 1.67 km/h (mountain working site). Despite downhill travel of the loaded skidder (–9.6%), the speed of skidding in the mountainous terrain is much lower than the speed in the hilly region, as the result of the driver’s decision, who could not drive such a large load at a higher speed (5.34 m3). As expected, the unloaded skidder travelled faster in the hilly region than the unloaded skidder downhill in the mountainous terrain. On the basis of equations, skidder speeds were calculated for different distances, and they are shown in Figure 14 together with other constant parameters. Due to downhill travel of the loaded skidder in the selective felling of the mountainous region, the speeds of unloaded and loaded travel are similar, and in the hilly region the loaded skidder travels uphill at a much lower speed that the unloaded skidder. Generally, it can be concluded that in a hilly region travel speeds are higher due to smaller load. By comparison between skidder speeds at the working sites and those obtained by calculation and measurement presented in Table 5 (Horvat and [u{njar 2005), it can be concluded that the driver used »the 1st fast gear« in driving the unloaded skidder at the mountain working site, and »the 2nd fast gear« at the hilly working site. In downhill timber skidding at the mountain working site of Senj »the 1st slow

Fig. 13 Average speeds Slika 13. Prosje~ne brzine kretanja 20

Fig. 14 Skidder speeds on skid road and felling site Slika 14. Brzine vo`nji skidera po vlaci i sje~ini gear« was used, and in uphill timber skidding at the hilly working site of \ur|evac »the 2nd slow gear« was used. On the basis of the used transmission gears and obtained travel speeds of unloaded and loaded skidders, assessment may be made of how good the transmission ratios are of the power transmission system, and the most loaded transmission gear pairs in timber skidding performed by skidders may be established. The average speed of pulling out the cable at hilly working sites was 1.10 km/h at an average distance of 10.5 m, and pulling of the cable was faster at the mountain working site (1.66 km/h) at a higher average distance (21.8 m). Multiple regression analysis showed that the time of pulling the cable at the mountain working site is significantly affected by terrain distance and slope, and in the preparatory felling by distance and air temperature. Winching of timber was slower (0.99 km/h) in hilly areas after preparatory felling than in mountain stands after selective felling (1.8 km/h). Multiple regression analysis showed that the time of load winching at the mountain working site is significantly affected by terrain distance and accessibility, and in the preparatory felling only by distance. It is known that the speeds of pulling and winching depend on terrain and stand factors, technical characteristics of the winch and cable, as well as on the distance of pulling the cable and size of individual loads. Based on technical data on winch Hittner 2 x 80, Horvat and [u{njar (2005) calculated the Croatian Journal of Forest Engineering 28(2007)1


Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

Table 5 Measured and calculated speeds of the skidder ECOTRAC 120V Tablica 5. Mjerene i prora~unate brzine kretanja skidera ECOTRAC 120V Transmission gear (Forward) Stupanj prijenosa (naprijed)

Speed, km/h – Brzina, km/h measured mjerena

calculated prora~unata

1 Slow gear – 1. Spori hod

3.01

2.9

2 Slow gear – 2. Spori hod

5.17

5.3

3 Slow gear – 3. Spori hod

8.65

8.7

4 Slow gear – 4. Spori hod

13.58

14.1

5 Slow gear – 5. Spori hod

20.72

21.1

1 Fast gear – 1. Brzi hod

4.02

4.1

2 Fast gear – 2. Brzi hod

7.25

7.4

3 Fast gear – 3. Brzi hod

11.88

12.3

4 Fast gear – 4. Brzi hod

19.36

19.8

5 Fast gear – 5. Brzi hod

28.87

29.7

nominal winching speeds of 1.26 m/s (4.32 km/h) with empty drum, and 2.24 m/s (8.06 km/h) with full drum. It can be clearly seen that lower winching speeds were attained than the calculated nominal speeds. The reason lies in the fact that during winching the engine ran at lower revolution rates, causing lower oil flow in the winch drive hydraulic system and this resulted in lower winching speed. Nominal winching speeds can be attained at the nominal engine rotation speed. Taking into account the known dependence of pressure in the hydraulic system on the second power of the pump rotation speed, it can be concluded that the winch attained still sufficient tractive forces at lower engine speed. Considering the working possibilities of the winch and winching requirements at the working sites of \ur|evac and Senj, it can be concluded that the winch can be successfully used under severe conditions (higher terrain slope, larger loads) when higher winching resistances are encountered.

5.7 Standard times, daily outputs and skidding costs – Norme vremena, dnevni u~inci i tro{kovi privla~enja Standard times, daily outputs and skidding costs were calculated in dependence on skidding distances for both working sites. The unloaded skidder consumes 1.34 to 4.46 minutes per cycle at a distance ranging between 100 m and 500 m at the hilly working site of \ur|evac, and between 3.88 and 10.83 minutes per cycle at the same distance at the mountain working site of Senj. The loaded skidder usually needs more time at the same Croatian Journal of Forest Engineering 28(2007)1

D. HORVAT et al.

skidding distances. So, at the hilly working site a loaded skidder requires 1.60 to 9.01 minutes per cycle, and in the mountain 5.09 to 14.26 minutes. Travel times of unloaded and loaded skidders at the landing are only shown for the distance of 100 m, which corresponds approximately to the average skidder travel distance at most working sites. Consequently the unloaded skidder consumed 1.00 minute for a distance of 100 m at the landing at the hilly working site of \ur|evac, and 1.39 minutes at the working site of Senj. At the landing, the loaded skidder consumes 1.37 minutes and 2.07 minutes, respectively. For other operations at the landing at the hilly working site of \ur|evac, the skidder consumes 4.07 minutes and 6.90 minutes at the mountain working site of Senj. The skidder working time at a felling site involves all working operations (positioning, pulling the cable, bunching, winching), which take place at individual working sites, and it is considered as the average time consumed for a cycle, i.e. fixed time. So the skidder consumed 4.07 minute by cycle at the hilly working site of \ur|evac, and 25.69 minute at the mountain working of Senj, which is 3.3 times more. This can be explained by more time required for positioning (moving) and bunching (terrain accessibility and workers’ skill), by double longer distance of pulling and winching, as well as by terrain configuration, or work methods (harvesting density). Total travel time of the skidder cycle at the hilly working site of \ur|evac ranges between 23.21 and 37.34 minutes, and at the mountain working site of Senj between 53.10 and 72.12 minutes. Standard time at the hilly working site of \ur|evac ranges between 8.35 min/m3 and 13.43 min/m3, and at the mountain working site of Senj between 9.94 min/m3 and 13.51 min/m3. According to the calculated values, the daily output from 57.49 m3/day and 35.74 m3/day (100–500 m) can be achieved at the hilly working site. At the mountain working site, the daily output from 48.53 m3/day to 35.54 m3/day can be achieved for the same distance (Table 6). Costs per product unit increase with the increase of skidding distance. The daily calculation of direct costs of the researched skidder amount to EUR 214.92 according to the official calculations of costs of »Hrvatske {ume« d.o.o. Zagreb for the year 2007. In the preparatory felling at a skidding distance from 100 m to 500 m at the hilly working site of \ur|evac, the costs range between 3.74 EUR/m3 and 6.01 EUR/m3. At the mountain working site of Senj at a distance from 100 m to 500 m, the costs range between 4.45 EUR/m3 and 6.05 EUR/m3. For

21


D. HORVAT et al.

Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

1.00 1.00 1.00 1.00 1.00

100 + 100 200 + 100 300 + 100 400 + 100 500 + 100

3.88 5.62 7.36 9.09 10.83

5.09 7.38 9.67 11.97 14.26

1.39 1.39 1.39 1.39 1.39

Allowance time, min Dodatno vrijeme, min

Effective time, min Efektivno vrijeme, min

Feling site work, min Rad u sje~ini, min

Daily output, m3/dan Dnevni u~inak, m3/day

1.60 3.45 5.30 7.15 9.01

Standard time, min/m3 Norma vremena, min/m3

1.34 2.12 2.90 3.68 4.46

Preparatory felling (hill) – Pripremni sijek (brdo) 1.37 7.91 4.07 17.29 5.92 1.37 7.91 4.07 19.92 6.82 1.37 7.91 4.07 22.55 7.72 1.37 7.91 4.07 25.18 8.62 1.37 7.91 4.07 27.81 9.53 Selective felling (mountain) – Preborna sje~a (planina) 2.07 25.69 6.90 45.02 8.08 2.07 25.69 6.90 49.05 8.80 2.07 25.69 6.90 53.08 9.53 2.07 25.69 6.90 57.11 10.25 2.07 25.69 6.90 61.14 10.98

Total time per cycle, min Ukupno vrijeme turnusa, min

100 + 100 200 + 100 300 + 100 400 + 100 500 + 100

Loaded skidder, min Optere}eni skider, min

Unloaded skidder, min Neoptere}eni skider

Loaded skidder, min Optere}eni skider, min

Unloaded skidder, min Neoptere}eni skider, min

Skidding distance, m Udaljenost privla~enja, m

Skidder travel – Vo`nja traktora Felling site Roadside landing Sje~ina Pomo}no stovari{te

Work on landing, min Rad na pomo}nom stovari{tu, min

Table 6 Calculated travel times, standard times and daily outputs of skidder Tablica 6. Izra~unata vremena vo`nje, norma vremena i dnevni u~inci skidera

23.21 26.74 30.28 33.81 37.34

8.35 9.62 10.89 12.16 13.43

57.49 49.90 44.08 39.47 35.74

53.10 57.86 62.61 67.36 72.12

9.94 10.83 11.72 12.61 13.51

48.27 44.30 40.94 38.05 35.54

to 5.25 EUR/m3, which is by 0.37 EUR/m3, or 7.1% more than the costs for the hilly working site of Koprivnica.

6. Conclusions – Zaklju~ci

Fig. 15 Daily outputs depending on skidding distance Slika 15. Dnevni u~inci u ovisnosti o udaljenosti privla~enja the skidding distance of 300 m + 100 m, the costs amount to 4.88 EUR/m3 for the hilly working site. For the mountain working site the same costs amount

22

Morphological analysis was used for determining dependences between individual morphological characteristics of the skidder ECOTRAC 120V and for establishing that it belongs to the skidder family. The researched skidder has small width relative to length due to the requirements of its manoeuvrability in timber skidding on skid roads of up to 2.5 m in width. The unfavourable increase of the skidder length caused by the construction of the front and rear blade has no adverse effect on the skidder manoeuvrability due to a centrally installed articulated joint. The increase of the skidder unit mass has been observed in the whole skidder family. The achievable value of the tractive force at the wheels also depends on technical characteristics of the driving engine and transmission system, as well as on the skidder mass, which makes the effect of adhesive weight and the required soil traction. The increase of the engine power relative to skidder mass enabled Croatian Journal of Forest Engineering 28(2007)1


Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

higher travelling speed of the skidder and provided the wheel thrust force required for overcoming the tractive and rolling resistance, by which work efficiency would also be increased and particularly so on sloped terrain. Such considerations give justification for morphological analyses, because they provide the possibility of observing development trends of engines, as well as ways of finding the right design solutions for meeting the requirements for their use. Productivity expressed through standard times, daily outputs and costs are only slightly different at the hilly working site after preparatory felling and in the mountain with the selective forest management. The comparison of two working sites in the research of skidder productivity clearly shows that productivity primarily depends on harvesting density (working time at the felling site) and skidding speed, and that in this case a considerable difference in the size of the load is not a key factor of productivity in timber skidding.

D. HORVAT et al.

der mass 7t«, programa RAZUM Ministarstva znanosti, obrazovanja i {porta RH, Studija, 1–31. Krpan, A. P. B., Por{insky, T., Ze~i}, @., 2003: Studija o potrebnoj veli~ini zglobnog traktora (skidder) temeljem sastojinskih prilika glavnoga prihoda i primjenjene tehnologije. Znanstvena studija u okviru projekta »Razvoj, izrada i ispitivanje specijalnog {umskog vehicle – skidder mass 7t«, programa RAZUM Ministarstva znanosti, obrazovanja i {porta RH, 1–41. Krpan, A. P. B., Ze~i}, @., 2001: Analiyse der arbeit des Knickschleppers Timberjack 240 C beim holzrüken auf den neigungen (Analiza rada zglobnog traktora Timberjack 240 C kod privla~enja na nagibima). 35. Intenationales symposium Mechanisierung der waldarbeit, Brno, ^e{ka Republika, 13–27. Pi~man, D., Pentek, T., 2003: Tehni~ke zna~ajke sekundarnih {umskih prometnica u karakteristi~nim sastojinskim i stojbinskim uvjetima kao podloga za odre|ivanje pogodnih dimenzija skidder. Znanstvena studija u okviru projekta »Razvoj, izrada i ispitivanje specijalnog {umskog vehicle – skidder mass 7t«, programa RAZUM Ministarstva znanosti, obrazovanja i {porta RH, 1–39.

7. References – Literatura

Sever, S., 1980: Istra`ivanje nekih eksploatacijskih parametara traktora kod privla~enja drva. Disertacija, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–301.

Bekker, M., G., 1956: Theory of land locomotion, The University of Michigan Press, 1–499.

Sever, S., Horvat, D., 1985: »[umski zglobni traktor snage oko 60 kW«, Studija, Zagreb, ZI[, 1–187.

FBVA, 2003: CDR »500 Forstmaschinen – Maschinenbeschreibung und Seibstkostenrechnung«. Bundesampt und Forschungszentrum für Wald – Abteilung für Forsttechnik.

Sever, S., Horvat, D., 1992A: Skidders and forwarders database as source and help in determining morphological relationships. Proceedings of IUFRO workshop »Computer supported planning of roads and harvesting«, Feldafing, Germany, 196–200.

Hitrec V., Horvat, D., 1987: Jedna metoda odre|enja regresijskog modela na primjeru krivulje klizanja kota~a. Mehanizacija {umarstva 12(11–12): 177–181. Horvat D., 1996: Tractive parameters of four skidders used for wood transportation in mountain forest thining, ECE/ FAO/ILO & IUFRO Seminar on environmentally sound forest roads and wood transportation, Sinaia, Rumunjska, 377–381. Horvat, D., Goglia, V., [u{njar, M., 2002: Some technical and ergonomic characteristics of thinning skidder Ecotrac, International conference »Logistic of wood technical production in the Carpathian mountains«, Zvolen, Slovakia, 80–93. Horvat, D., Sever, S., 1995: Some Properties of the Skidders used in Mountain Forest Stand Thinning, Proceedings XX. IUFRO World Congress, Tampere, Finland, 211–216. Horvat, D., [u{njar, M., 2005: Tehni~ke zna~ajke skidder Ecotrac 120V, Istra`ivanje i studija u okviru projekta »Razvoj, izrada i ispitivanje specijalnog {umskog vehicle – skid-

Croatian Journal of Forest Engineering 28(2007)1

Sever, S., Horvat, D., 1992B: Logging wheeld tractor databank for assistance in machine family evaluation. Proceedings of IUFRO workshop »Computer supported planning of roads and harvesting«, Feldafing, Germany, 281– 288. Sever, S., Horvat, D., 1997: Choosing and Application of Forest Soft Machines, 7th European ISTVS Conference, 7–10. October, 1997, Ferrara, Italy, 549–556. Ze~i}, @., 2001: Proizvodnost i tro{kovi traktora u brdskim proredama (Productivity and costs of tractor in thinnings on hilly terrain) Zagreb. Znanstvena knjiga: Znanost u potrajnom gospodarenju hrvatskim {umama, 507–523. Ze~i}, @., Krpan, A. P. B., Stanki}, B., 2004: Privla~enje oblovine traktorom Timberjack 240C iz oplodne sje~e u uvjetima [umarije Velika Pisanica. Skidding of rounwood by tractor Timberjack 240 C from regeneration felling in conditions of forest office Velika Pisanica. [umarski list 128(11–12): 671–678.

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Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

Sa`etak

Morfolo{ke i proizvodne zna~ajke traktora Ecotrac 120V U prigorskim i brdskim predjelima za privla~enje drva upotrebljavaju se u prvom redu kota~ni skideri opremljeni {umskim vitlom. U prigorskim i brdskim {umama u Hrvatskoj za privla~enje se iz oplodnih i prebornih sje~a drva koriste skideri s vitlom. Danas u Hrvatskoj trenuta~no radi oko 300 skidera u vlasni{tvu poduze}a »Hrvatske {ume« d.o.o. Zagreb te oko 100 skidera (procjena) u vlasni{tvu privatnih poduzetnika. Temeljem potreba hrvatskoga {umarstva za takvim na~inima privla~enja drva, trenuta~noga broja skidera i mogu}nosti proizvodnje tvornice »Hittner« d.o.o. nastala je ideja o razvoju doma}ega skidera mase preko 7 tona. Osnovna je zamisao da novonastali skider bude u potpunosti pogodan zahtjevima izvo|enja radova privla~enja drva u hrvatskim {umama. Cilj je rada morfolo{kom ra{~lambom utvrditi izvedivost i opravdanost zahtjevanih morfolo{kih i tehni~kih zna~ajki skidera te ustanoviti njegovu proizvodnost na dvama karakteristi~nim radili{tima pri privla~enju drva iz oplodne i preborne sje~e. Osnovne su dimenzije i raspored masa skidera ECOTRAC 120V prikazane na slici 2. Za potrebe morfolo{ke ra{~lambe kori{tena je baza podataka koja sadr`i 91 tip skidera. Odabrano je devet osnovnih morfolo{kih zna~ajki skidera: duljina (L), {irina (B), visina do krova kabine (HC), masa (m), snaga motora (P), indeksi oblika (HC/L) i (W/L), jedini~na masa (gm). Utvr|ene su korelacijske ovisnosti izme|u odre|enih morfolo{kih zna~ajki skidera. Ispitivani se skider odlikuje malom {irinom vozila s obzirom na duljinu zbog potrebe njegova kretanja pri privla~enju drva na izgra|enim trakorskim putovima ukupne {irine do 2,5 m, te ve}om snagom motora u odnosu na masu skidera. Nepovoljan rast duljine skidera s pove}anjem mase ne utje~e na kretnost skidera zbog sredi{nje postavljenoga zgloba. Pove}anjem snage motora u odnosu na masu skidera omogu}eno je pove}anje brzine kretanja skidera uz ostvarivanje potrebne obodne sile na kota~ima za svladavanje otpora vu~e i otpora kotrljanja, ~ime bi se ujedno pove}ala u~inkovitost rada. Ova razmatranja pokazuju da su morfolo{ke ra{~lambe opravdane jer se mogu uo~iti smjerovi razvoja strojeva te na~ini pronala`enja konstrukcijskih rje{enja za zadovoljavanje zahtjeva njihove uporabe. Istra`ivanje proizvodnosti provedeno je na dvama radili{tima: na brdskom radili{tu \ur|evac obavljen je pripremni sijek, a na planinskom radili{tu Senj preborni sijek u sastojini s prete`itim udjelom bukve. Pri privla~enju drva skiderom ECOTRAC 120V na oba radili{ta povratnom metodom kronometrije mjereni su utro{ci vremena radnih operacija i zahvata te proveden studij rada i vremena skidera. Odgovaraju}im su metodama prikupljeni pomo}ni mjerni i opisni podaci. Matemati~ko-statisti~ka je obrada podataka provedena u ra~unalnom programu Statistica 7. Na osnovi provedenoga studija vremena odre|ena je struktura ukupno utro{enoga vremena, efektivnoga vremena i op}ih vremena. Na slici 11 prikazana je struktura oblikovanih vremena turnusa za vo`nju po sje~ini i vlaci na udaljenost od 300 m te za vo`nju po pomo}nom stovari{tu od 50 m. Brzine su punih i praznih traktora izra~unate pomo}u vremena koja su izra~unata multiplom linearnom regresijskom analizom. Pri izra~unu vremena vo`nje optere}enoga traktora uzeti su sljede}i utjecajni parametri: udaljenost (l), stanje tla (st), nagib puta (a), prosje~na dnevna temperatura (T) i obujam tovara (q). Kod neoptere}enoga traktora uzeti su isti parametri osim obujma tovara. Kod optere}enih traktora po pomo}nom stovari{tu promatrana je udaljenost (l), obujam tovara (q) i broj komada u tovaru (n), a kod neoptere}enih samo udaljenost vo`nje. Prosje~ne brzine kretanja neoptere}enih traktora iznose 5,69 km/h na brdskom radili{tu, odnosno 2,20 km/h na planinskom radili{tu (slika 13). Optere}eni se traktori kre}u prosje~nom brzinom od 3,55 km/h (brdsko radili{te) i 1,67 km/h (planinsko radili{te). Na temelju jednad`bi izra~unate su za razli~ite udaljenosti brzine skidera i prikazane na slici 14. Zbog kretanja optere}enoga skidera niz nagib na planinskom, prebornom radili{tu brzine su prazne i pune vo`nje sli~ne, a u brdu se optere}eni skider kre}e uzbrdo mnogo sporije od neoptere}enoga. Op}enito, u brdu su brzine vo`nje ve}e zbog manjega tovara. Temeljem ra{~lambe izmjerenih i prora~unatih brzina kretanja skidera ECOTRAC 120V mo`e se zaklju~iti da je voza~ skidera koristio stupanj prijenosa »1. brzi hod« pri kretanju neoptere}enoga traktora na planinskom radili{tu, odnosno »2. brzi hod« na brdskom radili{tu. Pri privla~enju drva skiderom niz nagib na planinskom radili{tu Senj kori{ten je stupanj prijenosa »1. spori hod«, a pri privla~enju drva uz nagib na brdskom radili{tu \ur|evac stupanj prijenosa »2. spori hod«. S obzirom na kori{tene stupnjeve prijenosa i ostvarene brzine kretanja neoptere}enoga i optere}enoga skidera mo`e se donijeti sud o dobroj izvedenosti prijenosnih odnosa sustava

24

Croatian Journal of Forest Engineering 28(2007)1


Morphological characteristics and productivity of skidder ECOTRAC 120V (11–25)

D. HORVAT et al.

prijenosa snage, ali isto tako o najoptere}enijim stupnjevima prijenosa pri radu skidera na privla~enju drva. Multipla regresijska analiza pokazala je da na vrijeme izvla~enja u`eta na planinskom radili{tu signifikantno djeluju udaljenost i nagib terena, a u pripremnom sijeku udaljenost i temperatura zraka. Na vrijeme privitlavanja tovara na planinskom radili{tu signifikantno djeluju udaljenost i prohodnost, a u pripremnom sijeku samo udaljenost. Prosje~ne su brzine izvla~enja u`eta manje od prora~unatih nazivnih brzina. Razlog le`i u tome da je pri radu vitla kori{ten manji broj okretaja motora i time manji protok ulja u hidrauli~nom sustavu za pogon vitla, {to je rezultiralo manjom brzinom privitlavanja. Nazivne se brzine privitlavanja mogu ostvariti uz najve}i broj okretaja motora odnosno najve}i protok ulja u hidrauli~nom sustavu. S obzirom na radne mogu}nosti vitla i zahtjeve privitlavanja na radili{tima mo`e se zaklju~iti da se vitlom mo`e raditi i pri te`im uvjetima (ve}i nagibi terena, ve}i tovari) kada se pojavljuju ve}i otpori privitlavanja. Prozvodnost iskazana normom vremena, dnevnim u~inkom i tro{kom u ovisnosti o udaljenosti privla~enja neznatno se razlikuje na radili{tima. Usporedbom dvaju radili{ta pri istra`ivanju proizvodnosti skidera vidljivo je da zna~ajna razlika u veli~ini tovara nije klju~ni ~imbenik pri privla~enju drva. Klju~ne rije~i: skider ECOTRAC 120V, morfolo{ka ra{~lamba, privla~enje drva, dnevni u~inak, tro{kovi

Authors’ address – Adresa autorâ:

Received (Primljeno): January 8, 2007 Accepted (Prihva}eno): March 2, 2007 Croatian Journal of Forest Engineering 28(2007)1

Prof. Dubravko Horvat, PhD. e-mail: horvat@sumfak.hr Asst. Prof. @eljko Ze~i}, PhD. e-mail: zecic@sumfak.hr Asst. Prof. Marijan [u{njar, PhD. e-mail: susnjar@sumfak.hr Forestry Faculty of Zagreb University Department of Forest Engineering Sveto{imunska 25 HR-10 000 Zagreb CROATIA

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Orginal scientific paper – Izvorni znanstveni rad

Traffic load of forest roads as a criterion for their categorization – GIS analysis Hrvoje Neve~erel, Tibor Pentek, Dragutin Pi~man, Igor Stanki} Abstract – Nacrtak The categorisation of forest roads can be based on several different criteria. In this paper, the outlines of the primary forest traffic infrastructure were divided according to the traffic load typical of long-distance transportation of timber. The survey was conducted in the management unit of Veprina~ke {ume, forest office of Opatija, forest administration of Buzet. This paper defines the methodology of forest roads categorisation using the GIS analysis, which should become a mandatory tool in development of forest roads network in Croatia. Traffic load of forest roads as a criterion for their categorisation can be used for the rationalisation of construction and maintenance expenses of the primary forest traffic infrastructure, while additional researches should define the standards for construction and maintenance of each category of forest roads. Keywords: forest road, traffic load, categorisation, relative openness, further timber transportation

1. Introduction – Uvod The total quantity of forest roads, their spatial distribution and prescribed technical characteristics must be sufficient to enable a high-quality management of forest ecosystems with minimum starting and additional financial investments. Construction and maintenance of the primary forest road infrastructure network, as well as the construction and repairs of the secondary forest road network (skid roads) make a very important element of the overall expense structure related to forest management. The aim is to construct a spatially well-positioned network of forest roads whose technical characteristics will enable the fulfilment of all the tasks set forth by the Management Plan for a specific forest area. While achieving this goal, we are also trying to reach the satisfactory quality level with the least possible financial investments. The Geographical Information System (GIS) is today used in almost all segments of society, so forestry could not have stayed aside. When it comes to forest roads, the GIS was used so far in planning of the primary and secondary forest road network, i.e. in drafting of the primary and secondary studies of forest opening (Pentek 2002). The basic aim of this paper is to show how successfully the GIS may be used in combination with the appropriate software applications, for the rationalisation of the expenses of construction and mainCroatian Journal of Forest Engineering 28(2007)1

tenance of forest communications, with particular regard to forest roads. Poto~nik et al. (2005a) state that the development of good studies of the primary opening of forests could significantly rationalise and control the expenses for construction and maintenance of the primary forest road infrastructure. Pentek et al. (2006) believe that during its amortisation period, the quality of a constructed primary forest road infrastructure can only be retained by regular maintenance interventions whose frequency and intensity depend on the category of the specific forest road. The establishment of the GIS of the surveyed area, together with the analysis of the secondary forest openness and simulation of timber assortments’ transportation from the felling site to the asphalt public roads network is used as a basis for planning and rationalisation of construction and maintenance expenses.

2. Research issues – Problematika istra`ivanja 2.1 Categorisation of forest roads – Kategorizacija {umskih prometnica In relation to the traffic density, [iki} et al. (1989) divided forest roads into primary and secondary forest communications.

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Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

The primary forest communicatons include forest roads. These are permanent constructions, which enable continuous traffic of motor vehicles for the purpose of fulfilment of all tasks set forth by the Management Plan. These roads consist of the lower and upper layer and have all the technical characteristics of roads, thus permanently bereaving the forest of its productive area (proportionally to the road’s width, i.e. the road’s body). The secondary forest communications include skid roads and skid trails. The secondary forest communications are constructions occasionally used for the fulfilment of tasks set forth by the Management Plan. Their primary purpose is timber skidding and forwarding. [iki} et. all (1989) distinguish four forest road categories with five road body widths. If a road has two lanes, its body width varies between 6.0 and 7.5 metres; in case of a single-lane road, the width varies between 5.0 and 5.5 metres. According to the same source, the following technical characteristics of forest communications in Croatia were prescribed: (1) the minimum radiuses of horizontal curves, (2) the necessary broadening of roads in curves, (3) transversal slopes of forest roads, (4) maximum longitudinal slopes of forest roads and (5) minimum allowed radiuses of transversal curves. Regarding the frequency of use and considering the maintenance requirements, Pi~man and Pentek (1996) divide forest roads as follows: Þ primary forest roads, used throughout the year with permanent maintenance needs, Þ secondary forest roads, used only occasionally when needed; their maintenance is periodical. Poto~nik (1996) states that forest roads exist in a multifunctional forest, and accordingly they also become multifunctional. Furthermore, he divides forest roads’ functions as follows: roads with forestry function and roads with a non-forestry function. It is very important to analyse the trend of change of structure and intensity of forest roads traffic, which certainly increases their maintenance expenses, but also the expenses of construction, due to high traffic security requirements and technical equipment demands. The intensity of non-forestry functions of forest roads, which generate additional expenses, is quite variable and depends on the spatial position of the forest road as well as on the surrounding environment and its prospects. According to the FAO guidelines (FAO 1998), the classification was made of forest communications on sloping areas: Þ access roads, Þ main roads,

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Þ secondary roads (feeder roads), Þ skid road, Þ skid trails. Based on frequency of use and importance, Poto~nik et al. (2005b) divide forest roads into three main categories: main forest roads, secondary forest roads and access forest roads, whereby the technical characteristics are prescribed, and construction standards are the same for all three categories, while the difference is noticeable in their basic purpose, frequency and intensity of traffic and, finally, construction and maintenance expenses in the amortisation period. According to Poto~nik et al. (2005a), assuming constant habitat conditions, cumulative traffic load and intensity are mostly affected by the position and distance of an individual forest road section from the public road, then by the secondary forest roads and finally by turnaround location on the forest road. Again, the closer the sections of a forest road are to the conjunction of the forest road with a public road, the better they have to be constructed in compliance with higher construction standards and regular maintenance in shorter intervals, which accordingly justifies the categorisation of not only forest roads, but also of specific sections of forest roads as well. The first step that has to be taken before the beginning of opening up of a specific forest area is the analysis of the existing network of primary and secondary forest communications. In order to do this, it is necessary to have a cadastral plan of primary and secondary forest communications in a digital form. According to Pentek et al. (2003), the cadastral plan of primary and secondary forest road infrastructure provides as follows: Þ precise and detailed overview of the existing resources of a specific forest area, Þ the analysis of the existing state of primary and secondary forest communications development, Þ observing of contingent needs, deficiencies and faults regarding forest road infrastructure, Þ planning and control of expenses of forest roads maintenance and expenses for repairs of skid roads, Þ development of a detailed building site survey when harvesting is carried out in a specific forest area.

3. Research area – Podru~je istra`ivanja The researches were performed within the selective forests area of the management unit of VepriCroatian Journal of Forest Engineering 28(2007)1


Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

na~ke {ume, forest office of Opatija, forest administration of Buzet. The total surface of the management unit is 1,950.87 ha, whereof 1,899.23 ha is forest covered, 43.36 ha is non-forest covered, 3.12 ha is a non-forest covered unproductive soil and 5.16 ha is unfertile soil. The Veprina~ke {ume management unit (Fig. 1) is a part of the ]i}arija massif, situated between 45°20’ and 45°24’ of Northern latitude and 14°11’ and 14°16’ of Eastern longitude. The highest peak is at an altitude of 1144 metres, while the lowest point is at the altitude of 760 metres. A half-tree-length method is used in felling and processing. Timber is extracted by skidders equipped with cable winches. This method of primary timber transportation requires a well-developed secondary openness. Due to the terrain configuration and orographic development, skid roads have to be constructed. The scaling of roundwood is performed within the felling site. The basic characteristics of forest opening-up and timber harvesting are steep, orographically diverse mountainous terrain, richness of the karst relief phenomena, shallow soils and rocky bedrock, as well as heavy construction material categories. The average slope inclination of the terrain ranges between 5 and 30°. Further to the above, the necessity for providing a good primary and secondary openness is obvious. The 10-year harvesting volume (81,131.75 m3) is of a high quality; the main commercial tree species is beech. The primary forest openness amounts to 8.58 m/ha and 16.78 m/ha, respectively, if an old Italian macadam public road is taken into account. The secondary forest openness is 101.94 m/ha.

H. NEVE^EREL et al.

4. Objective and methodology – Cilj i metode rada 4.1 Objective – Cilj rada The objective of this paper is to calculate the traffic load of each component of the primary forest road infrastructure by use of the GIS analysis. The traffic load will be calculated assuming that timber transportation is carried out by truck. The following working phases are planned: Þ establishment of GIS of the researched area, Þ defining positions of landings, Þ analysis of the secondary openness of the management unit of Veprina~ke {ume, Þ defining of gravitation zones, Þ defining of traffic load of the primary forest road infrastructure, Þ categorisation of the primary forest road infrastructure.

4.2 Working methodology – Metode rada 4.2.1 Positioning of forest roads with GPS – Snimanje {umskih prometnica GPS ure|ajem Positioning of forest roads was carried out by the Trimble Geoexplorer 3 GPS. The recording interval was 5 seconds. For the positioning of forest roads, we used an external antenna attached to the terrain vehicle, while skid roads were passed on foot. The primary and secondary forest communications were positioned by the so-called snap-back method during the period of vegetation dormancy, in accordance with the previously defined almanac. The data obtained were downloaded with the GPS Pathfinder Office 2.80 application package and entered into the ArcView 3.1 application package, and afterwards integrated into previously prepared digital maps. 4.2.2 Data analysis – Obrada podataka 4.2.2.1 Defining of opened areas for the chosen length of the skidder’s winch cable – Odre|ivanje otvorenih povr{ina za odabranu duljinu u`eta vitla zglobnoga traktora

Fig. 1 Position of the management unit of Veprina~ke {ume Slika 1. Polo`aj GJ Veprina~ke {ume Croatian Journal of Forest Engineering 28(2007)1

The length of the skidder’s winch cable, used within the researched habitat and stand conditions, is 60 metres. Due to the terrain’s slope and surface obstacles, timber assortments cannot be winched from a 60-metres distance from both sides of forest roads. The »useful« length of a winch cable is 45 metres (Neve~erel 2004).

29


H. NEVE^EREL et al.

Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

Fig. 2 Defining priorities with the secondary forest roads due to the exclusion of the »multiple opened areas« Slika 2. Odre|ivanje prioriteta kod sekundarnih {umskih prometnica zbog isklju~ivanja »vi{estruko otvorenih povr{ina« In digital maps, the 45-metre buffers were laid on both sides of the primary and secondary forest roads. The marked area, i.e. the area within the buffered zone, is opened for the chosen length of the skidder’s winch cable, meaning that the timber assortments within the buffered zone can be winched without a skidder’s descent from the forest roads. This can also apply for the reverse situation.

Each junction of the secondary and primary forest rorad presents a landing (of higher or lower capacity). Each of the primary forest roads is divided into sections (segments between the two landings) as the smallest unit for which a traffic load is calculated. The processed timber assortments, except on landings, are stored along public and forest roads.

4.2.2.2 The analysis of the secondary openness – Ra{~lamba sekundarne relativne otvorenosti

5. Research results – Rezultati istra`ivanja

The analysis is conducted for each forest road, for each category of the forest roads (primary and secondary), for each subcompartment and finally for the entire management unit. When analysing relative secondary openness, priority is given to the forest roads, whose ranking starts with those of higher classes and proceeds to lower class roads. When it comes to the roads of the same rank, priority is given in accordance with the constructing sequence. If we assume a homogenous structure of all stand and habitat factors within one subcompartment, the results of the analysis of the secondary relative openness can be used for defining harvesting volume, which is prescribed by the Management Plan at a subcompartment level gravitating towards an individual forest road. The harvesting volume, which is situated outside the buffered zones, is distributed to forest roads proportionally to their participation in the distribution of a 10-year harvesting volume within the buffered zones.

30

5.1 The analysis of the relative secondary openness – Ra{~lamba sekundarne relativne otvorenosti Regarding the total opened area in comparison to the total area, the average relative openness of the management unit of Veprina~ke {ume is derived. It amounts to 72.34%, of which 14.65% accounts for roads and 57.69% for skid roads. The unopened area covers 27.66% of the management unit area.

5.2 Defining of traffic load of the primary forest road infrastructure – Odre|ivanje prometnoga optere}enja primarne {umske prometne infrastrukture Figure 3 shows the total traffic load of public roads with marked gravitational areas in the horizontal alignment of junctions with forest roads. There are two versions of load calculations for the primary forest road infrastructure. The first version Croatian Journal of Forest Engineering 28(2007)1


Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

H. NEVE^EREL et al.

Compartment Odsjek

Area, ha Povr{ina, ha

Removal, m3 Etat, m3

Table 1 Relative openness and harvesting volume distribution Tablica 1. Relativna otvorenost i raspodjela etata

1a 2a 3a 4a 5a 5b 6a 6b 7a 7b 8a 9a 10a 11a 12a 13a 14a 15a 16a 17a 18a 19a 19b 20a 20b 21a 22a 23a 24a 25a 26a 27a 28a 29a 30a 31a 32a 33a 33b 34a 35a 36a 37a 38a 39a 40a

30.56 64.35 40.35 30.56 13.18 19.73 32.57 13.80 47.58 13.64 61.63 35.52 24.83 35.73 37.48 47.47 56.85 25.97 38.89 54.30 26.51 16.83 25.82 46.61 3.97 41.43 23.12 27.96 25.57 47.81 48.48 34.21 48.26 25.58 44.99 26.84 36.39 28.69 5.76 46.23 28.10 48.31 34.65 37.16 20.86 30.35

895.00 1,521.50 2,237.50 1,190.35 751.80 67.13 1,512.55 0.00 537.00 0.00 2,640.25 1,320.13 895.00 1,136.65 1,700.50 1,807.90 2,622.35 1,118.75 2,022.70 2,452.30 671.25 554.90 223.75 1,342.50 35.80 1,548.35 1,163.50 1,163.50 1,342.50 895.00 2,595.50 1,360.40 2,461.25 1,476.75 2,774.50 0.00 1,378.30 1,432.00 268.50 1,745.25 1,118.75 2,640.25 2,971.40 1,611.00 1,745.25 1,969.00

Openness, % Otvorenost, % Public and Forest Skid roads roads Traktorski putovi Javne i {umske ceste 59.20 0.00 56.62 9.79 50.69 21.29 68.76 8.00 56.38 21.44 27.62 0.00 47.13 37.41 5.42 66.46 9.51 0.26 16.32 4.10 39.33 0.53 70.48 3.89 53.30 31.84 64.02 17.65 63.03 8.75 58.11 17.88 57.31 5.91 63.59 22.99 64.82 10.85 70.86 15.13 43.82 27.77 81.53 1.02 22.53 0.00 64.77 16.42 65.06 0.00 65.97 17.71 66.46 24.61 58.26 22.49 62.04 26.28 58.02 22.48 85.20 7.01 68.60 23.80 84.48 10.25 78.59 13.19 72.91 16.80 19.03 5.08 71.38 6.07 52.40 33.05 16.52 0.00 80.62 9.83 70.94 25.76 80.03 10.02 86.35 9.55 11.38 7.22 61.38 22.62 74.75 12.86

Croatian Journal of Forest Engineering 28(2007)1

Total Ukupno 59.20 66.41 71.98 76.76 77.82 27.62 84.54 71.88 9.78 20.42 39.86 74.38 85.14 81.67 71.77 75.99 63.22 86.58 75.67 85.99 71.60 82.55 22.53 81.20 65.06 83.67 91.07 80.75 88.32 80.50 92.21 92.41 94.74 91.77 89.70 24.11 77.45 85.45 16.52 90.45 96.70 90.05 95.90 18.60 84.00 87.62

Unopenned areas, % Neotvorena podru~ja, % 40.80 33.59 28.02 23.24 22.18 72.38 15.46 28.12 90.22 79.58 60.14 25.62 14.86 18.33 28.23 24.01 36.78 13.42 24.33 14.01 28.40 17.45 77.47 18.80 34.94 16.33 8.93 19.25 11.68 19.50 7.79 7.59 5.26 8.23 10.30 75.89 22.55 14.55 83.48 9.55 3.30 9.95 4.10 81.40 16.00 12.38

Timber that gravitates towards, m3 Drvo koje gravitira, m3 Public and Forest Skid roads roads Traktorski putovi Javne i {umske ceste 895.00 0.00 1,372.52 148.98 1,761.22 476.28 1,095.17 95.18 590.64 161.16 67.13 0.00 946.68 565.87 0.00 0.00 535.58 1.42 0.00 0.00 2,626.17 14.08 1,268.72 51.40 610.03 284.97 936.00 200.65 1,551.76 148.74 1,484.71 323.19 2,467.36 154.99 861.54 257.21 1,803.19 219.51 2,081.28 371.02 484.82 186.43 549.25 5.65 223.75 0.00 1,122.01 220.49 35.80 0.00 1,274.20 274.15 877.20 286.30 901.83 261.67 989.68 352.82 693.79 201.21 2,413.59 181.91 1,036.57 323.83 2,208.86 252.39 1,282.00 194.75 2,308.51 465.99 0.00 0.00 1,294.63 83.67 958.78 473.22 268.50 0.00 1,573.65 171.60 830.58 288.17 2,375.79 264.46 2,687.58 283.82 1,494.71 116.29 1,350.48 394.77 1,715.70 253.30

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41a 41.41 42a 37.46 42b 2.13 43a 62.41 44a 39.36 45a 37.22 46a 40.12 47a 54.58 48a 26.90 49a 41.87 Total – Ukupno, m3 Average – Prosje~no, %

Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

Removal, m3 Etat, m3

Area, ha Povr{ina, ha

Compartment Odsjek

H. NEVE^EREL et al.

1,790.00 1,637.85 0.00 2,774.50 2,103.25 1,700.50 2,685.00 2,908.75 912.90 1,700.50 81,131.75

Openness, % Otvorenost, % Public and Forest Skid roads roads Traktorski putovi Javne i {umske ceste 73.21 17.82 74.28 20.27 55.93 0.00 61.43 32.55 79.05 9.64 42.11 0.00 84.62 4.89 36.78 29.05 50.91 11.79 66.80 18.16 57.69

14.65

Total Ukupno

Unopenned areas, % Neotvorena podru~ja, %

91.03 94.55 55.93 93.98 88.69 42.11 89.50 65.83 62.70 84.96

8.97 5.45 44.07 6.02 11.31 57.89 10.50 34.17 37.30 15.04

72.34

27.66

Timber that gravitates towards, m3 Drvo koje gravitira, m3 Public and Forest Skid roads roads Traktorski putovi Javne i {umske ceste 1,471.06 318.94 1,305.88 331.97 0.00 0.00 1,871.51 902.99 1,900.47 202.78 1,700.50 0.00 2,553.79 131.21 2,063.75 845.00 805.23 107.67 1,391.64 308.86 68,970.79 12,160.96

Fig. 3 Traffic load of public roads Slika 3. Prometno optere}enje javnih cesta assumes a truck as a mean for long-distance transportation of timber, while in the second version it is a truck with trailer (Fig. 4). The net mass values of transported timber were calculated in comparison to the 10-year harvesting volume that was transported on each of the roads at the beginning of its horizontal alignment, where the average volume mass of beech timber (1.07 t/m3) was used for scaling (Anon. 1966). The number of truck cycles (n) presents the total number of passes of the chosen means of long-distance transportation

32

of timber required to transport the entire harvesting volume (assuming a truck or truck with trailer is fully loaded at departure and empty at arrival). The following equation was used: mnet n= (1) ⋅2 (mmax − mts ) mnet – 10-year timber mass, t mmax – maximum mass allowed, t mmax – mass of a chosen means of long-distance transportation of timber, t Croatian Journal of Forest Engineering 28(2007)1


Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

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Fig. 4 Maximum dimensions and loads allowed for trucks with trailer Slika 4. Najve}e dopu{tene dimenzije i optere}enja kamiona s prikolicom

The maximum mass allowed of a truck is 26 t, 40 t for a truck with trailer (Anon. 2005). The mass of the chosen means of transportation in the first case is 14.138 t; 18.723 t in the second case (Krpan et al 2002). The gross mass was calculated as a sum of net mass and the total mass of turns of the chosen means of transportation. The loads of the primary forest road infrastructure regarding trucks and trucks with trailers are shown in Table 2. The elements of the primary forest road infrastructure, in accordance to the traffic load presented as gross tons per year, are divided into five categories: Þ I. class (>80.000 t) Þ II. class (60.000 – 80.000 t) Þ III. class (40.000 – 60.000 t) Þ IV. class (20.000 – 40.000 t) Þ V. class (<20.000 t) Categorisation was made based on the analysis of traffic load for the primary forest road infrastructure of the management unit of Veprina~ke {ume (one road is class IV, while all the others are class V). The results are shown in Figure 5. Croatian Journal of Forest Engineering 28(2007)1

6. Conclusions – Zaklju~ci End finally, based on the results obtained, the following conclusions are derived: Þ Determination of forest roads by use of GPS and snap-back method presents a very fast and sufficiently accurate technique, which enables integration of the recorded forest roads and skid roads into maps of a 1:5000 scale. Þ Once established, the cadastral plans of forest roads enable accurate and detailed overview of the existing resources of a specific forest area, analysis of the existing state of primary and secondary forest openness as well as insight into possible needs, deficiencies and faults. It also enables planning and control of expenses of maintenance of forest roads and repairs of skid roads, development of detailed studies of harvesting operations, etc. Þ The method of buffered zones, combined with relative openness, is a very good indicator of efficiency of a high-quality spatial distribution of the primary and secondary forest communications.

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Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

Table 2 The load of public and forest roads at the horizontal alignment 0+00,00 hm Tablica 2. Optere}enje javnih i {umskih cesta na staciona`i 0 + 00,00 hm Road mark Oznaka ceste Public road 1 Javna cesta 1 Public road 2 Javna cesta 2 Forest road VS1 [umska cesta VS1 Forest road VS2 [umska cesta VS2 Forest road VS3 [umska cesta VS3 Forest road VS4 [umska cesta VS4 Forest road VS5 [umska cesta VS5 Forest road VS6 [umska cesta VS6 Forest road VS7 [umska cesta VS7 Forest road VS8 [umska cesta VS8 Forest road VS9 [umska cesta VS9 Forest road VS10 [umska cesta VS10 Forest road VS11 [umska cesta VS11 Forest road VS12 [umska cesta VS12 Forest road VS13 [umska cesta VS13

10-years removal 10-years nett mass 10-godi{nji etat 10-godi{nja neto masa

Truck – Kamion 10-years gross mass No. of cycles 10-godi{nja bruto masa Broj turnusa t

m3

t

81,131.75

86,811

14,636

293,735

8,160

239,591

51,880.44

55,512

9,360

187,844

5,218

153,209

460.32

493

84

1,680

46

1,354

1,821.63

1,949

328

6,586

184

5,394

21,226.85

22,713

3,830

76,861

2,134

62,668

3,348.02

3,582

604

12,122

336

9,873

2,242.89

2,400

404

8,112

226

6,631

4,074.09

4,359

734

14,737

410

12,036

2,374.73

2,541

428

8,592

238

6,997

1,200.44

1,284

216

4,338

120

3,531

1,837.57

1,966

332

6,660

184

5,411

1,957.48

2,095

354

7,099

196

5,764

1,190.10

1,273

214

4,299

120

3,520

9,774.46

10,459

1,764

35,398

984

28,882

4,932.36

5,278

890

17,860

496

14,564

Þ The survey of the opened area for the chosen skidder’s winch cable length, as opposed to non-opened area, clearly illustrates which forest areas need further intervention in terms of additional secondary opening-up. Also, the presence of the so-called »multiply opened areas«, not defined as necessary, illustrates the non-productive lengths of the secondary forest roads. Þ The analysis of the secondary relative openness indicates that the significant amount of

34

Track and trailer – Kamion s prikolicom 10-years gross mass No. of cycles 10-godi{nja bruto masa Broj turnusa t

the forest area is opened through public and forest roads, meaning that a great portion of net harvesting volume can be winched from public or forest road. This information was also taken into account when it came to defining traffic load where, except for the landings at skid road junctions, the roadside landings were taken into consideration as concentration spots of winched net harvesting volume. Þ The results of the conducted survey of traffic load indicate that specific forest roads, even Croatian Journal of Forest Engineering 28(2007)1


Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

H. NEVE^EREL et al.

Fig. 5 The overview of the categorisation of traffic load Slika 5. Prikaz kategorizacije prometnoga optere}enja

the individual sections of the same forest road, should be constructed taking into consideration different construction standards, i.e. applying different technical conditions. This would enable the rationalisation of construction expenses and consequently enable the use of the saved financial funds for the investment into further opening-up of still non-opened forest areas. Þ Forest roads with higher traffic frequency require regular periodical maintenance of a higher quality and in shorter intervals. Croatian Journal of Forest Engineering 28(2007)1

7. References – Literatura Anon., 1966: [umarsko – tehni~ki priru~nik. Nakladni zavod »Znanje«, Zagreb. Anon., 2005: Pravilnik o tehni~kim uvjetima vozila u prometu na cestama. Narodne novine 92/2005. FAO, 1998: A Manual for the planning, design and construction of forest roads in steep terrain. p. 1–188. Krpan, A. P. B., Horvat, D., Por{insky, T., [u{njar, M., 2002: Tehni~ke i tehnolo{ke zna~ajke kamiona SCANIA P124 B 6x4 NZ400, prikolice Narkö i dizalica Jonsered 1090. Studija, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–69.

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Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

Neve~erel, H., 2004: Primjena GIS-a pri odre|ivanju prometnog optere}enja primarne {umske prometne infrastrukture. Diplomski rad, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–45.

logical Studies on the Primary Opening of Hilly-Mountain Forests. International Forest Information Technology Congress – Forest IT, September 3 – 4, 2002, Helsinki, Finland, Proceedings, 1 – 10.

Pentek, T., 2002: Ra~unalni modeli optimizacije mre`e {umskih cesta s obzirom na dominantne utjecajne ~imbenike. Disertacija, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–271.

Pi~man, D., Pentek, T., Neve~erel, H., 2006: Katastar {umskih prometnica – postoje}e stanje, metodologija izradbe i koristi od njega. Glasnik za {umske pokuse, posebno izdanje 5: 635–646.

Pentek, T., Pi~man, D., Krpan, A. P. B, Por{insky, T., 2003: Inventory of primary and secondary forest communications by the use of GPS in Croatian mountainous forest. Proceedings of International workshop Austro 2003 – High Tech Forest Operations for Mountainous Terrain, October 5–9, 2003, Schlaegl, Austria, University of Natural Resources and Applied Life Sciences Viena, CD-ROM, 1–12. Pentek, T., Pi~man, D., Neve~erel, H., 2005: Planiranje {umskih prometnica – postoje}e stanje, odre|ivanje problema i smjernice budu}eg djelovanja. Nova meh. {umar. 26: 55–63. Pentek, T., Pi~man, D., Neve~erel, H., 2006: Uspostava optimalne mre`e {umskih cesta na terenu – smjernice unapre|enja pojedine faze rada. Glasnik za {umske pokuse, posebno izdanje 5: 647–663. Pi~man, D., Pentek, T., 1996: ^imbenici koji utje~u na opravdanost izgradnje mre`e {umskih prometnica. Savjetovanje »Skrb za hrvatske {ume od 1846. do 1996.«, Znanstvena knjiga 2 »Za{tita {uma i pridobivanje drva«, 293–300.

Poto~nik, I., 1996: Mnogonamenska raba gozdnih cest kot kriterij za njihovo kategorizacijo. Disertacija, Universa v Ljubljani, Biotehni{ka fakulteta, Oddelek za gozdarstvo, 1–241. Poto~nik, I., Pentek, T., Pi~man, D., 2005a: Impact of traffic characteristics on forest roads due to forest management. Croatian Journal of Forest Engineering 26(1): 51–57. Poto~nik, I., Yoshioka, T., Miyamoto, Y., Igarashi, H., Sakai, H., 2005b: Maintenance of forest road network by natural forest management in Tokyo University Forest in Hokkaido. Croatian Journal of Forest Engineering 26(2): 71–78. [iki}, D. i dr., 1989: Tehni~ki uvjeti za gospodarske ceste. Znanstveni savjet za promet JAZU, Zagreb, 1–40. Toma{i}, @., Su~i}, @., Slunjski, M., Pola~ek, M., 2005: Ovodobno stanje prijevoza drva kamionskim skupovima u {umarstvu RH. Nova mehanizacija {umarstva 26: 65–71.

Pi~man, D., Pentek, T., Por{insky, T., 2002: Application of Modern Technologies (GIS, GPS,..) in Making Methodo-

Sa`etak

Prometno optere}enje {umskih cesta kao kriterij njihove kategorizacije – GIS analiza Izgradnja i odr`avanje primarne mre`e {umske prometne infrastrukture te izgradnja i popravci sekundarne mre`e {umskih prometnica (traktorskih putova) ~ine zna~ajnu sastavnicu unutar ukupne strukture tro{kova povezanih s gospodarenjem {umom. Potrebno je izgraditi prostorno dobro polo`enu mre`u {umskih prometnica koja }e svojim tehni~kim zna~ajkama omogu}avati izvr{avanje svih zadataka predvi|enih programom gospodarenja odre|enim {umskim podru~jem. Pri dosezanju toga cilja nastoji se posti}i zadovoljavaju}a razina kakvo}e uza {to manja financijska ulaganja. Istra`ivanja su provedena u prebornim {umama GJ Veprina~ke {ume [umarije Opatija, U[P Buzet. Ukupna je povr{ina gospodarske jedinice 1950,87 ha, od ~ega je obraslo 1899,23 ha, neobraslo proizvodno 43,36 ha, neobraslo neproizvodno 3,12 ha te neplodno 5,16 ha. Gospodarska jedinica Veprina~ke {ume (slika 1) dio je planinskoga masiva ]i}arije. Nalazi se izme|u 45°20’ i 45°24’ sjeverne zemljopisne {irine te 14°11’ i 14°16’ isto~ne zemljopisne du`ine. Najvi{a je to~ka na 1144 m n. v., dok se najni`a to~ka nalazi na 760 m n. v. Primarna otvorenost GJ Veprina~ke {ume iznosi 8,58 m/ha, odnosno 16,78 m/ha, ako se u obra~un uzme stara talijanska javna cesta s gornjim strojem izgra|enim od tucanika. Sekundarna otvorenost iznosi 101,94 m/ha. Cilj je ovoga rada bio izra~un prometnoga optere}enja svake od sastavnica primarne {umske prometne infrastrukture primjenom GIS-a u ra{~lambi. Uspostavom se GIS-a istra`ivanoga podru~ja, ra{~lambom sekundarne otvorenosti te simulacijom transporta drvnih sortimenata od sje~ine do sustava asfaltiranih javnih cesta odre|uje prometna optere}enost primarne {umske prometne infrastrukture kao podloga za planiranje i racionalizaciju tro{kova izgradnje i odr`avanja. Prometno }e se optere}enje izra~unati za kamionski transport drva.

36

Croatian Journal of Forest Engineering 28(2007)1


Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

H. NEVE^EREL et al.

Planirani su ovi radni koraci: uspostava GIS-a istra`ivanoga podru~ja, odre|ivanje polo`aja pomo}nih stovari{ta, ra{~lamba sekundarne otvorenosti GJ Veprina~ke {ume, utvr|ivanje gravitacijskih podru~ja, odre|ivanje prometnoga optere}enja primarne {umske prometne infrastrukture i kategorizacija sastavnica primarne {umske prometne infrastrukture. Primarne i sekundarne {umske prometnice snimljene su GPS ure|ajem TrimbleGeoExplore 3 tzv. povratnom metodom u vrijeme mirovanja vegetacije prema prethodno odre|enomu kalendaru. Ra{~lamba se sekundarne relativne otvorenosti provodi za svaku {umsku prometnicu, za pojedinu kategoriju {umskih prometnica (primarne i sekundarne), za svaki odsjek i kona~no za ~itavu gospodarsku jedinicu. Pri ra{~lambi prioritet imaju primarne {umske prometnice idu}i od onih vi{ega reda k onima ni`ega reda. Kod {umskih prometnica istoga reda prioritet se odre|uje sukladno redoslijedu izgradnje. Srednja sekundarna relativna otvorenost gospodarske jedinice Veprina~ke {ume iznosi 72,34 %, od ~ega na ceste otpada 14,65 %, a na traktorske putove/vlake 57,69 %. Neotvoreno se podru~je prote`e na 27,66 % povr{ine gospodarske jedinice. Pretpostavi li se homogena struktura svih sastojinskih i stani{nih ~imbenika unutar odsjeka, tada se rezultati ra{~lambe sekundarne relativne otvorenosti mogu iskoristiti za odre|ivanje etata, propisanoga programom gospodarenja na razini odsjeka, koji gravitira pojedinoj {umskoj prometnici. Etat koji se nalazi izvan ome|enih povr{ina raspore|uje se na {umske prometnice sukladno njihovu udjelu u raspodjeli etata unutar ome|enih povr{ina. Ra{~lamba je sekundarne relativne otvorenosti i raspodjela etata prikazana u tablici 1. Optere}enje primarne {umske prometne infrastrukture izra~unato je za dvije ina~ice. U prvoj je ina~ici kao sredstvo daljinskoga transporta drva kori{ten kamion, dok je u drugoj ina~ici sredstvo daljinskoga transporta drva kamion s prikolicom (slika 4). Vrijednosti su neto mase izvezenoga drvnoga obujma izra~unate prema izvezenomu etatu svake od cesta na njezinoj po~etnoj staciona`i, pri ~emu je za prera~un mase iz obujma kori{tena prosje~na obujamna te`ina bukve u sirovom stanju od 1,07 t/m3 (Anon. 1966). Broj je kamionskih tura ukupan broj prolazaka odabranoga sredstva daljinskoga transporta drva potreban za izvo`enje ukupnoga etata (punoga transportnoga sredstva u odlasku i praznoga transportnoga sredstva u dolasku). Bruto je masa dobivena kao zbroj neto mase i ukupne mase broja kamionskih tura odabranoga transportnoga sredstva. Optere}enja su primarne {umske prometne infrastrukture pri upotrebi kamiona i kamiona s prikolicom prikazana u tablici 2. Sastavnice primarne {umske prometne infrastrukture, prema prometnomu optere}enju iskazanom u bruto tonama/godi{nje, podijeljene su u 5 kategorija: Þ I. reda (>80 000 t) Þ II. reda (60 000 – 80 000 t) Þ III. reda (40 000 – 60 000 t) Þ IV. reda (20 000 – 40 000 t) Þ IV. reda (<20 000 t). Temeljem ra{~lambe prometnoga optere}enja za primarnu {umsku prometnu infrastrukturu gospodarske jedinice Veprina~ke {ume izra|ena je kategorizacija (jedna je cesta IV. reda, a ostale V. reda), koja je prikazana na slici 5. Temeljem dobivenih rezultata istra`ivanja mogu se izvesti ovi zaklju~ci: Þ Jednom uspostavljen katastar {umskih prometnica omogu}uje to~an i detaljan uvid u postoje}e resurse odre|enoga {umskoga podru~ja, analizu postoje}ega stanja primarne i sekundarne otvorenosti {uma te uo~avanje eventualnih potreba, nedostataka i manjkavosti, planiranje i kontrolu tro{kova odr`avanja {umskih cesta i popravaka traktorskih putova, izradu elaborata radili{ta pri sje~i i dr. Þ Metoda ome|enih povr{ina u kombinaciji s relativnom otvoreno{}u vrlo je dobar pokazatelj uspje{nosti kvalitetnoga prostornoga rasporeda primarnih i sekundarnih {umskih prometnica. Þ Prikaz otvorenoga podru~ja za odabranu duljinu u`eta vitla, za razliku od neotvorenenoga, zorno prikazuje na kojim je {umskim povr{inama potrebna daljnja intervencija radi provedbe sekundarnoga otvaranja. Tako|er prisutnost tzv. »vi{estruko otvorenih povr{ina«, koje nisu definirane kao nu`ne, prikazuje neproduktivne duljine sekundarnih {umskih prometnica. Þ Ra{~lamba sekundarne relativne otvorenosti pokazala je kako je zna~ajna koli~ina {umske povr{ine otvorena javnim i {umskim cestama, odnosno kako se velika koli~ina neto etata mo`e privu}i s javne, odnosno {umske ceste. Takav je podatak uzet u obzir pri odre|ivanju prometnoga optere}enja gdje su, osim pomo}nih stovari{ta, na spojevima grana trakorskih putova, kao mjesta koncentracije privu~enoga neto etata, u obzir uzeta i »stovari{ta« uz cestu.

Croatian Journal of Forest Engineering 28(2007)1

37


H. NEVE^EREL et al.

Traffic load of forest roads as a criterion for their categorisation – GIS analysis (27–38)

Þ Rezultati provedene ra{~lambe prometne optere}enosti pokazuju kako odre|ene {umske ceste, pa ~ak i pojedine dionice iste {umske ceste, treba graditi po{tuju}i razli~ite standarde gradnje, odnosno primjenjuju}i druga~ije tehni~ke uvjete. Time je mogu}e racionalizirati tro{kove izgradnje te tako sa~uvana financijska sredstva investirati u daljnje otvaranje jo{ neotvorenih {umskih podru~ja. Þ Na {umskim cestama s ve}om frekvencijom prometa potrebno je provoditi ~e{}e periodi~no i kvalitetnije teku}e odr`avanje. Klju~ne rije~i: {umska prometnica, prometno optere}enje, kategorizacija, relativna otvorenost, daljinski transport drva

Authors’ address – Adresa autorâ:

Received (Primljeno): December 15, 2006 Accepted (Prihva}eno): March 2, 2007

38

Hrvoje Neve~erel, BSc. e-mail: hnevecerel@sumfak.hr Asst. Prof. Tibor Pentek, PhD. e-mail: pentek@sumfak.hr Asst. Prof. Dragutin Pi~man, PhD. e-mail: picman@sumfak.hr Igor Stanki}, BSc. e-mail: stankic@sumfak.hr Forestry Faculty of Zagreb University Department of Forest Engineering Sveto{imunska 25 HR-10 000 Zagreb CROATIA Croatian Journal of Forest Engineering 28(2007)1


Preliminary note – Prethodno priop}enje

Roundwood flow analysis in Slovenia Mitja Pi{kur, Nike Krajnc Abstract – Nacrtak On the basis of roundwood flow model, two roundwood balances were prepared. A wide range of available data was taken into consideration; data quality was evaluated and a proposal for improving their quality developed. Results of roundwood balance in the reference year 2004 showed that if official data for annual removals are considered, a lack of 536,000 m3 occurs. In the case of modelled (enlarged) removals, a roundwood balance is positive. Wood flow and data analysis should play an important role as part of strategic planning and decision making at sectorial, local, regional and national levels. Keywords: roundwood, roundwood balance, roundwood flow analysis, MFA, forest industry, home consumption, Slovenia

1. Introduction – Uvod For a strategic development planning in the sphere of branches associated with wood, roundwood flow analyses are needed. A research into roundwood flows enables an overview of a momentary situation and serves as a basis for any decisions to be made on development of the forestry and wood processing sectors. In the last twenty years, roundwood balances and flow analyses have been made for numerous countries (e.g. Palmer 2000, Binder et al. 2003, Hashimoto and Moriguchi 2004, Hekkert et. al. 2000, Krajnc and Pi{kur 2006), which served as a basis for development planning or as a basis for the assessment of illegal removals in forests. Strategic development planning of the branches associated with wood requires information on material flows of wood in wood production chain. Some data and investigation results show that the state of affairs in this respect has been poorly researched in Slovenia. With roundwood flow analysis, the balance between production and primary use of roundwood in Slovenia is established. The obtained relations indicate the adjustment between both productions, quality and availability of data, import-export balance, and significance of wood in home consumption.

2. Working methods – Metode rada Owing to the very specific conditions, a model (Fig. 1) was made, which in fact covers the entire Croatian Journal of Forest Engineering 28(2007)1

complexity of wood flow in Slovenia (Krajnc and Pi{kur 2006). As a basis, the material flow model (MFA) was used (Bruner and Rechberger 2004). The principles of the products’ life cycle assessment (LCA)(e.g. Jensen et al. 1997) were also applied, considering that material flow analysis is its component part. MFA clearly presents the material flows, showing correlations between the sources, users and flows. The MFAresults are controlled by roundwood balance. To quantify the wood flow in Slovenia, a method was applied for analysing the existing and available data on production of roundwood and its further use. With the synthesis method, the gathered data were incorporated in two balances, i.e. roundwood balance and wood wastes balance (Krajnc and Pi{kur 2006). All the data and balances relate to the reference year 2004. By taking import and export into account, the relation between net removals in the forests and the estimated roundwood use was named roundwood balance (B1) and calculated according to the following formula: B1 = Pneto – SOKL – IOKL + UOKL

(1)

Pneto – Net removals in the reference year (m3) SOKL – Registered consumption of roundwood in industry, households and energy production IOKL – Total roundwood export UOKL – Total roundwood import

39


M. PI[KUR and N. KRAJNC

The model of roundwood flows is defined with: Þ Roundwood removals and production, Þ Roundwood import and export, Þ Roundwood use in wood processing, Þ Roundwood use in households, Þ Roundwood use for energy production. When assessing the actual removals in forests, two different approaches were used, i.e. »top down« and »bottom up«. For the first evaluation of roundwood balance, official data were used for net removals and forest timber assortment (TQA). For the second evaluation, on the other hand, net removals were evaluated on the basis of total registered roundwood use, when the TQA structure was partially changed as well. In view of the registered or estimated use, net removals in privately owned forests

Roundwood flow analysis in Slovenia (39–46)

were increased. The disunion between the registered removals in privately owned forests has also been noted by Veseli~ (2004), Medved (2005) and Pi{kur (2005). The amount of removals in state owned forests was not changed. The statistics regarding import and export of goods is monitored by the Statistical Office of the Republic of Slovenia (SURS), whereas the data are collected by the Customs Office of the RS. Import and export to EU countries are covered by the Intrastat system, the data on import and export from non-EU countries by the Extrastat system. The data on the amounts of separate combined classes of forest timber assortment were surveyed by Combined Nomenclature (CN8). The basic data on roundwood import and export (in kg and m3) were obtained from the statistic database of SURS (2006c). On the basis of structure

Fig. 1 Roundwood and wood wastes model in Slovenia Slika 1. Prikaz modela potro{nje drva u Sloveniji 40

Croatian Journal of Forest Engineering 28(2007)1


Roundwood flow analysis in Slovenia (39–46)

of databases, roundwood was divided (separately for coniferous and deciduous trees) into: Þ saw and veneer logs (L), Þ pulpwood (PW) and other industrial roundwood (OIR), Þ fuelwood (WF). Roundwood use is the highest and from the aspect of economy also the most important in industry. Roundwood use in woodworking activities (SindOKL) is the sum of: Þ 1. production of sawnwood (S1) Þ 2. production of plywood and veneer (S2) Þ 3. production of wood pulp (S4) Þ 4. production of particle boards and fibreboards (S5) Þ 5. use of other industrial wood (S7) The estimate of roundwood use in woodworking activities is based on official data (SURS), on research carried out (e.g. Internova 2006, ZGS 2006, GIS 2004a and ICP 2006 questionnaires), and on data obtained directly from firms. The entire home consumption was divided in use of saw and veneer logs, use of other industrial wood, and use of fuelwood. The data on home use were obtained from the inventory of rural economies (SURS 2000, 2003, 2005), results of the questionnaires filled by forest owners in the Council of Sol~ava (GIS 2002), results of the general questionnaire filled by forest owners (GIS 1995), and results of the analysis of use of wood for heating purpose in Slovenia (SURS 2006a in 2006b). On the basis of the existing results, use of roundwood for heating purposes and use of logs

M. PI[KUR and N. KRAJNC

and other industrial wood in households was estimated. The quantities of roundwood, used as wood for energy production, were estimated separately for households and energy systems (heating plants, hydroelectric power stations, the systems of simultaneous production of heat and electricity). The data on roundwood use for energy production purposes in larger systems were obtained from the questionnaire on wood biomass producers (GIS 2004b), which enclosed only major and registered producers of wood biomass. The data on wood use for fuel were obtained from the questionnaire on energy use in households (SURS 2006a, b).

3. Results and discussion – Rezultati i rasprava On the basis of the prepared model and the objectives of our research, two balances were made. The results are presented in partial frameworks of wood flow in Slovenia, with the frameworks interacting with each other and supplementing each other as to their context at the same time. The final and most essential result is the presentation of two variants of roundwood wood balance in Slovenia, i.e.: Þ Roundwood official balance Þ Roundwood model balance As far as removals are concerned, it was assumed that the data on quantities used in production of forest timber assortments in state owned forests were realistic, and hence they were not altered. To a great

Fig. 2 Comparison between official and model net removals (year 2004) Slika 2. Usporedba stvarno ostvarenoga i oblikovanoga modela neto etata (godina 2004) Croatian Journal of Forest Engineering 28(2007)1

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M. PI[KUR and N. KRAJNC

Roundwood flow analysis in Slovenia (39–46)

extent, however, we altered the data on removals in other forests, i.e. by increasing the removals of deciduous trees in other forests with the factor 1.8, and the removals of conifers with the factor 1.1. Our comparison between the official and model net removals is presented in Figure 2. In 2004, 52,000 m3 of logs were imported according to our calculations, 351,000 m3 of pulpwood and other industrial wood, and 8,500 m3 of fuelwood. In the same year, Slovenia exported 108,000 m3 of saw and veneer logs, 76,000 m3 of pulpwood and other industrial wood, and 63,000 m3 of fuelwood. When comparing the import and export, we can conclude that in 2004 Slovenia was a net exporter of logs and wood for fuel and a great net importer of roundwood used for cellulose, chip and fibre boards, and other industrial wood. The use of wood in woodworking activities was divided as follows: production of sawnwood and veneer, production of wood pulp, particle boards and fibreboards, and use of other industrial wood. The quantities of roundwood are shown by individual activities in Table 1 (Slovene Forestry Institute’s own calculations). The greatest amount of roundwood is used in the production of sawnwood, which originates mostly from Slovene forests. On the basis of our calculations and gathered data we estimate that altogether 1,410,000 m3 of logs were sawn up in 2004, 1,100,000 m3 of which were conifers and 310,000 m3 deciduous. In registered companies, 1,243,000 m3 of saw logs were sawn. The difference (167,000 m3) was sawn up for home use by unregistered sawmills and forest owners. It is interesting that in 1985 the official production of sawnwood was 1,078,000 m3, 72% of which went to the sawnwood of coniferous trees. By

allowing for the yield factor during sawing up (0.67), the use was 1,610,000 m3 of saw logs. It is a very difficult task to estimate the quantities of roundwood used in sawmills due to insufficient and inconsistent data. The poor quality of data is also indicated by the former estimates of roundwood quantities sawn up in Slovenia (from 760,000 m3 to 1,960,000 m3) and by various data on the number of corporate bodies registered for wood cutting and planning. These data indicate that more accurate analyses are to be implicitly made into the state of sawmilling industry in Slovenia. In 2004, the production of wood pulp was a significant wood consumer in Slovenia. Between 2000 and 2005, roundwood use in the production of wood pulp oscillated around 500,000 m3. Use of roundwood for the production of chemical wood pulp after closing of the production plant within Vipap Videm Krško d.d. ceased in 2006. In the last few years, on the other hand, the quantity of roundwood for the production of mechanical wood pulp has increased (66,000 m3 in 2003, and 117,000 m3 in 2004). The third biggest consumer of industrial roundwood is the production of chip and fibre boards, by which about 200,000 m3 of particularly deciduous tree wood are used annually. The registered quantities of roundwood, which enter the production of veneer in Slovenia, amounted to 91.000 m3 in 2004. Under the production of veneer, the production of sliced and peleed veneer was taken into consideration. Other industrial roundwood, which is processed in industry, encloses pitwood, wood for the production of tannin, and wood for the production of poles. Industrial use of this kind of roundwood has been greatly reduced in comparison with the situation

Table 1 Use of roundwood in woodworking industry for the year 2004 (in m3) Tablica 1. Potrošnja drva u drvnoj industriji za 2004. godinu (u m3) Use of wood in woodworking industry Potrošnja drva u industriji Production of sawnwood Proizvodnja piljenoga drva Production of veneer Proizvodnja furnira Production of wood pulp, particleboards and fibreboards Proizvodnja celuloze, iverica i vlaknatica Use of other industrial wood Potrošnja drugoga industrijskoga drva Together Ukupno

42

Total Ukupno

Originating from import Drvo iz uvoza

Domestic wood Drvo doma}ega porijekla

1,243,000

14,000

1,229,000

91,000

38,000

53,000

693,000

309,000

384,000

63,000

27,000

36,000

2,090,000

388,000

1,702,000

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Roundwood flow analysis in Slovenia (39–46)

M. PI[KUR and N. KRAJNC

Table 2 Material flows and roundwood balance in Slovenia (data are in m3) Tablica 2. Tokovi sirovina i drvna bilanca Slovenije (u m3) Components of net removals Sastavnice slubenoga neto etata Roundwood use in woodworking industry (S1) Potrošnja oblovine u drvnoj industriji (S1) Home consumption (S2) Potrošnja u doma}instvima (S2) Roundwood use for energy production in biomass systems (S3) Potrošnja oblovine pri proizvodnji energije u sustavima na biomasu (S3) Sum of roundwood use (SOKL) Ukupna potrošnja oblovine (SOKL) Import (UOKL) Uvoz (UOKL) Export (IOKL) Izvoz (IOKL) Official balance of roundwood (B1u) Slubena drvna bilanca (B1u) Components of model net removals Sastavnice oblikovanoga neto etata Roundwood use in woodworking industry (S1) Potrošnja oblovine u drvnoj industriji (S1) Home consumption (S2) Potrošnja u doma}instvima (S2) Roundwood use for energy production in biomass systems (S3) Potrošnja oblovine pri proizvodnji energije u sustavima na biomasu (S3) Sum of roundwood use (SOKL) Ukupna potrošnja oblovine (SOKL) Import (UOKL) Uvoz (UOKL) Export (IOKL) Izvoz (IOKL) Model balance of roundwood (B1m) Oblikovana drvna bilanca (B1m)

Tokl1 1,371,668 L

Tokl2 454,186 OIR+PW

1,334,000

756,000

167,000

53,000

Tokl3 725,086 WF

Pu_neto 2,550,940 RW 2,090,000

939,000

1,159,000

3,000

3,000

1,501,000

809,000

942,000

3,252,000

52,000

351,000

9,000

412,000

108,000

76,000

63,000

247,000

–185,332

–79,814

–270,914

–536,060

Tokl1 1,583,000 L

Tokl2 531,100 OIR+PW

Tokl3 1,028,000 WF

Pm_neto 3,142,100 RW

1,334,000

756,000

167,000

53,000

2,090,000 939,000

1,159,000

3,000

3,000

1,501,000

809,000

942,000

3,252,000

52,000

351,000

9,000

412,000

108,000

76,000

63,000

247,000

26,000

–2,900

32,000

55,100

Remark: RW – Roundwood, L – Logs, PW – Pulpwood, OIR – Other industrial wood, WF – Woodfuel Napomena: RW – drvo, L – pilansko oblo drvo, PW – celulozno drvo, OIR – ostalo industrijsko drvo, WF – ogrjevno drvo

prior to 1990, when about 180,000 m3 of other industrial wood used to enter the market from forest production. In 2004, on the other hand, the registered use of this kind of roundwood was merely 63,000 m3. The analysis of wood for household purposes has shown that most of the wood is used for heating and sanitary water heating. Three independent studies (SURS 2006a, b, ZGS 2005) have shown that houseCroatian Journal of Forest Engineering 28(2007)1

holds use more than 1,000,000 m3 of wood per year for heating alone. A minor part of this wood are wood wastes and other wood mass. Apart from fuelwood, households also process and consume a little more than 220,000 m3 of saw logs and other industrial wood per year. Our supposition is that households use for their own needs 167,000 m3 of logs and 53,000 m3 of other industrial wood.

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Roundwood flow analysis in Slovenia (39–46)

According to the data obtained through the questionnaire initiated by GIS (2004b), less than 3,000 m3 of roundwood per year is used by large energy production systems (remote systems for the heating of settlements, the systems of simultaneous production of electricity and heat, boilers in industry). These systems otherwise use almost exclusively wood residues and wastes left after wood processing and, partially, other wood mass. Knowledge of individual utilizations of roundwood is of key importance for understanding the state of woodworking industry and for the elaboration of future development programs. In view of the data on roundwood use, 64% of all roundwood in Slovenia is used in woodworking industry, 36% in households, and negligibly little in energy production. Joint results of the roundwood flow analysis – separately by each individual use – are presented in Table 2. Two different estimates are given. In the first, the basis is made up of the official net removals, whereas in the second estimate, the basis is the model assessment of net removals in forests. Roundwood use is divided in three groups of use (S1–3) and in three groups in view of the forest timber assortments (K1–3). The official roundwood balance (B1u) was calculated by formula (2), the model balance (B1m) by formula (3). 3

B1u = Pu _ neto + U0 − ∑ Si − I 0 = i =1

= 2, 552, 940 + 412, 000 − 3, 252, 000 − 247, 000 = = −536, 000 m 3

(2)

B1u = Pm _ neto + U0 − ∑ Si − I 0 = i =1

Considering that high quality data are of key importance for making roundwood balances, the quality and availability of data should be well improved in the years to come. Furthermore, roundwood balances should be made annually. Thus a continued and high quality estimate of the current state would be provided. In the long run, on the other hand, we would be able to estimate the trends of future development in the branches of industry closely associated with forests and wood.

5. References – Literatura Binder, C. R., Hofer, C., Wiek, A., Scholz, R. W., 2003: Transition process towards improved regional wood flow by integrating material flux analysis and agent analysis: The case of Appenzell Ausserrhoden,Switzerland. Working paper 39. ETH Eidgenossische Technicshe Hochschule Zurich, Zurich, p. 1–24.

GIS, 1995: Rezultati ankete za zasebne lastnike gozdov – 1995. Gozdarski in{titut Slovenije, Ljubljana, unpublished.

= 3,142, 000 + 412, 000 − 3, 252, 000 − 247, 000 =

(3)

The differences between the official and model balances are large. There is a lack of more than 500,000 m3 of roundwood (net) in the official balance in Slovenia. The largest deficit is related to fuelwood (more than 270,000 m3) and logs (more than 185,000 m3). The available data on use of roundwood for heating purposes are relatively solid (similar to the estimate of 1,000,000 m3 from the sources by ZGS 2005, SURS 2006a, b), due to which the official figure on net removals for fuelwood (750,000 m3) is too low. As far as the model balance is concerned, the net removals were increased in view of the estimated use, which is presented in Table 2. In this case, the balance is positive. The production surplus is actually above the registered use of 55,100 m3, which is

44

4. Conclusion – Zaklju~ak

Bruner, P. H., Rechberger, H., 2004: Practical Handbook of Meterial Flow Analysis. Lewis publishers, London, p. 1–318.

3

= +55,100 m 3

less than 2% of the entire net removals. We presume that the quantity of roundwood, which is used by larger energy production systems (S9), is underestimated. The use of roundwood for household heating purposes is greatly reduced in the model as well. We also assess that the quantity of exported roundwood, which originates from privately owned forests, is greater and that it is not fully registered in SURS’s databases. Owing to the stated assumptions we estimate that the model balance is nearer to the actual situation regarding the production and use of roundwood than the official balance.

GIS, 2002: Rezultati ankete lastnikov gozdov v ob~ini Sol~ava. Gozdarski in{titut, Ljubljana, unpublished. GIS, 2004a: Rezultati ankete o koli~inah lesnih ostankov v Sloveniji. Gozdarski in{titut Slovenije, Ljubljana, unpublished. GIS, 2004b: Rezultati ankete proizvajalcev lesne biomase. Gozdarski in{titut Slovenije, Ljubljana, unpublished. Hashimoto, S., Moriguchi, Y., 2004: Data book: material and carbon flow of harvested wood in Japan. Center for Global Environmental Research: National Institute for Environmental Studies, Tsukuba (CGER; D034–2004). Hekkert, M. P., Joosten, L. A. J., Worrell, E., 2000: Analysis of the Paper and Wood Flow in The Netherlands. Resources, Conservation and Recycling 30(1): 29–48. ICP, 2006: Podatki o porabi lesa za proizvodnjo celuloze in vlaknin. In{titut za celulozo in papir, Ljubljana, unpublished. Croatian Journal of Forest Engineering 28(2007)1


Roundwood flow analysis in Slovenia (39–46)

M. PI[KUR and N. KRAJNC

INTERNOVA, 2006: Baza podatkov o `agarskih obratih 2002. Internova d.o.o. Ljubljana, unpublished. Jensen, A. A., Hoffman, L., Moller, B. T., Schmidt, A., Christiansen, K., Elkington, J., 1997: Life Cycle Assessment: a guide to approaches, experiences and information sources. European Environment Agency, p. 1–104. Krajnc, N., Pi{kur, M. 2006: Tokovi okroglega lesa in lesnih ostankov v Sloveniji. ZbGL 80: 31–54. Medved, M., 2005: Pomen statisti~nih raziskav za spremljanje gospodarjenje z zasebnimi dru`inskimi gozdovi v Sloveniji. V: Tka~ik, Boris (ur.), Urbas, Marina (ur.). 15. statisti~ni dnevi, Radenci, 7. – 9. november 2005. Komuniciranje z dajalci in uporabniki statisti~nih podatkov ter podpora EMU in Lizbonski strategiji: zbornik: proceedings volume. Ljubljana: Statisti~ni urad Republike Slovenije: Statisti~no dru{tvo Slovenije: = Statistical Office of the Republic of Slovenia: Statistical Society of Slovenia, p. 309–320. Palmer, C. E., 2000: The extent and causes of illegal logging: an analysis of a major cause of tropical deforestation in Indonesia. CSERGE, London, p. 1–33. Pi{kur, M., 2005: Mo`nosti sledenja certificiranega lesa v Sloveniji. Magistrsko delo. Ljubljana, samozalo`ba p. 1– 122.

SURS, 2003: Raziskovanje strukture kmetijskih gospodarstev: KME-JUNSTRK/3L. junij 2003, Statisti~ni urad RS, Ljubljana, unpublished. SURS, 2005: ‘Rezultati ankete KME-JUNSTRK/3L za leto 2005’. Ljubljana, Statisti~ni urad RS, unpublished. SURS, 2006a: Rezultati ankete APG 2004. Statisti~ni urad RS, Ljubljana, unpublished. SURS, 2006b: Rezultati ankete APEGG 2002 . Statisti~ni urad RS, Ljubljana, unpublished. SURS, 2006c: Banka statisti~nih podatkov. <http://bsp1h. gov.si/D2300.kom/komstart.html> (15. 5. 2006) Veseli~, @., 2004: Illegal logging in Slovenia. Joint UNECE/ FAO Workshop on Illegal Logging and Trade of Illegally-derived Forest Products in the UNECE Region Palais des Nations, UNECE/FAO, Geneva, p. 1–9. ZGS, 2005: Kon~no poro~ilo projekta: Preskrba in raba bioenergije ob so~asnem zagotavljanju trajnostnega gospodarjenja z gozdom. Zavod za gozdove Slovenije, Ljubljana, p. 1–185. ZGS, 2006: Rezultati ankete o `agarskih obratih v Sloveniji. Zavod za gozdove Slovenije, Ljubljana, unpublished.

SURS, 2000: Popis kmetijskih gospodarstev: POPIS-KME/ 10L. Statisti~ni urad RS, Ljubljana, unpublished.

Sa`etak

Ra{~lamba tokova drva u Sloveniji Za strate{ko razvojno planiranje u djelatnostima vezanima uz drvo potrebne su ra{~lambe tokova drva. Istra`ivanja tokova drva omogu}uju pregled trenuta~ne situacije i slu`e kao podloga za sve odluke koje se donose, a odnose se na razvoj {umarstva i sektora prerade drva. U pro{lih dvadeset godina drvne bilance i ra{~lambe tokova izra|ene su za brojne zemlje, koje slu`e kao osnova za planiranje razvoja ili kao podloga za procjenu ilegalnih sje~a u {umama. Strate{ko planiranje razvoja gospodarskih grana vezanih uz drvo zahtijeva informaciju o tokovima drvne sirovine u proizvodnom lancu. Ra{~lambom toka drva utvr|ena je bilanca izme|u proizvodnje i primarne preradbe drva u Sloveniji. Dobiveni odnosi pokazuju povezanost obiju djelatnosti, kakvo}e i dostupnosti podataka, bilance uvoza i izvoza, te upu}uju na zna~enje drva u doma}oj potro{nji. Sukladno pripremljenomu modelu i ciljevima istra`ivanja izra|ene su dvije bilance. Rezultati su predstavljeni u djelomi~nim okvirima tokova drva u Sloveniji, gdje su okviri u me|usobnoj interakciji nadopunjavaju}i jedan drugoga sukladno njihovu zna~enju. Krajnji je i najva`niji rezultat predstavljanje obiju ina~ica bilance obloga drva u Sloveniji: slu`bene bilance obloga drva i oblikovane bilance obloga drva. Zna~ajne su razlike uo~ene izme|u slu`bene i oblikovane bilance. U slu`benoj drvnoj bilanci Republike Slovenije nedostaje vi{e od 500 000 m3 (neto godi{nje). Najve}i se manjak odnosi na ogrjevno drvo (vi{e od 270 000 m3) te pilansko oblo drvo (vi{e od 185 000 m3). Postoje}i podaci o potro{nji ogrjevnoga drva razmjerno su stabilni, {to pokazuje da je neto etat ogrjevnoga drva po slu`benim podacima nedovoljan (750 000 m3). Ako se razmatra oblikovana drvna bilanca, neto je etat pove}an s obzirom na procjenu. U tom je slu~aju bilanca pozitivna. Proizvodni je vi{ak iznad registrirane potro{nje od 55 100 m3, {to je manje nego 2 % cjelokupnoga neto etata. Pretpostavka je da je podcijenjena koli~ina drva iskori{tena u velikim energetskim sustavima. Potro{nja ogrjevnoga drva u doma}instvima tako|er je vrlo umanjena u modelu. Osim toga pretpostavka je da je procijenjena koli~ina izvezenoga obloga drva, koje potje~e iz privatnih {uma, ustvari ve}a te da nije u potpunosti registrirana u

Croatian Journal of Forest Engineering 28(2007)1

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Roundwood flow analysis in Slovenia (39–46)

bazama podataka. Zbog navedenih pretpostavki stajali{te je da je oblikovana drvna bilanca bli`a stvarnoj situaciji s obzirom na proizvodnju i potro{nju drva nego slu`bena drvna bilanca. Imaju}i na umu da je visoka kakvo}a podataka veoma va`na za izradu drvne bilance, kakvo}a i dostupnost podataka trebale bi biti pobolj{ane u idu}im godinama. Nadalje, drvne bi se bilance trebale izra|ivati svake godine. Potrebno je osigurati stalnu i vrsnu procjenu trenuta~noga stanja. Dugoro~no gledano, mo}i }e se predvidjeti trendovi budu}ega razvoja u granama gospodarstva blisko vezanima uz {ume i drvo. Klju~ne rije~i: oblo drvo, drvna bilanca, ra{~lamba tokova drva, MFA, {umarstvo, doma}a potro{nja, Slovenija

Authors’ address – Adresa autorâ:

Received (Primljeno): December 20, 2006 Accepted (Prihva}eno): February 12, 2007

46

Mitja Piškur, MSc. e-mail: mitja.piskur@gozdis.si Nike Krajnc, PhD. e-mail: nike.krajnc@gozdis.si Slovenian Forestry Institute Department of Forest Technique and Economics Ve~na pot 2 1000 Ljubljana SLOVENIA Croatian Journal of Forest Engineering 28(2007)1


Subject review – Pregledni ~lanak

Development of a new concept for improvement of forest techniques in Croatia – Areas of possible contributions Ivan Martini}, Vencl Vondra, Mario [por~i} Abstract – Nacrtak The paper addresses a possible concept for improving forest techniques in Croatia as a response to challenges encountered by the Croatian forestry in its effort to satisfy the increased ecological, social and economic commitments. Achieving a safety culture in forestry, increasing energetic efficiency with a lesser impact on the environment, developing innovations and entrepreneurship and receiving more contributions from research activities are considered the key elements of the new concept. The concept of forest techniques improvement focuses on permanent education of specialised staff and on training and certification of working skills of workers and operators of forest mechanisation in particular. A major part of improvements in the quality and safety of forest work relates to mandatory licensing of forest contractors. The article advocates the creation and implementation of an energy efficiency strategy and lower dependence on traditional fuels and lubricants. The comparison of national and European research needs with the ongoing research activities in Croatia has shown that the current research programme is unable to achieve major improvements in the forestry techniques and technology. The solution lies in involving Croatian scientist in international and multidisciplinary research projects. Keywords: forestry, forest work safety, safety culture, training, education, fuel consumption

1. Introduction – Uvod Since the early 1990s the development of European forestry has evolved within the framework of forestry policy defined by broad social interests and goals. The framework was primarily outlined in the resolutions of ministerial conferences on the preservation of European forests (Strasbourg 1990, Helsinki 1993, Lisbon 1998, Vienna 2992). These resolutions promote sustainable forest management as the fundamental principle, while multipurpose uses of forest resources and benefits for ecological, economic and social needs of the society are defined as permanent objectives of such management. In such conditions forest operations as the most important and best recognized part of forestry activities must satisfy numerous requirements both in terms of the choice of technologies and means of work and of the level of education of specialised staff and forest workers themselves. The majority of transitional countries, including Croatia, are faced Croatian Journal of Forest Engineering 28(2007)1

with numerous difficulties in adjusting multiple aspects of forest work to the newly established criteria. This refers first of all to the belated introduction of high technologies and development of entrepreneurial activities in forestry (Rametsteiner and Yadlapalli 2004, Rametsteiner et al. 2004). To overcome the current problems of forest technology and techniques it is necessary to mobilise many areas and many professions. In general opinion, the steps to be taken relate particularly to: Þ Increasing the efficiency of the existing technologies and focusing on energetic efficiency, ecological acceptability and ergonomic suitability, Þ Developing new products and services for the purpose of lessening the dependence of business results on the production of roundwood, and Þ Establishing a culture of forest safety as the key factor for reducing risks and accidents.

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Some important areas of possible improvements of forestry techniques in Croatia will be discussed further on in the article.

2. Creating a culture of forest safety; increasing the efficiency, quality and humanisation of work in transition to high technologies – Postizanje kulture sigurnosti u {umarstvu; pove}anje djelotvornosti, kakvo}e i humanizacije rada na prijelazu prema visokim tehnologijama Forestry in transitional countries is characterized by a conspicuous delay in the application of cutting edge technologies of forest work mechanisation (central automated landings, work with harvesters, chippers and processors, extraction with forwarders) – where such application is justified and purposeful. Coupled with higher efficiency and humanisation of work, this would reverse the present negative statistics of accidents at work and occupational diseases in transitional countries. Several hundred forest workers are injured in Croatia every year. Along with construction and traffic, accident frequencies and fatality rates are 2–3 times higher than those recorded in other industrial sectors. Apart from significant social and economic impacts, the consequences of unsafe and inappropriately executed forest operations are also reflected on the environment, as the damage to forest ecological systems far outweighs the damage caused by the necessary technological processes. The risk of accidents and injuries of forest workers are primarily the consequence of unsatisfactory levels of organisation

and working techniques, where, as research shows (Martini} 1998), the main causes lie in poor training of professional staff and direct forest workers. According to ILO/FAO (1998), in order to reduce risks and stop negative trends in the health and safety of forest workers, it is necessary to establish a »safety culture«. This implies a clear mission and a synergistic effect of joint efforts by the participants in such a concept of safety culture: state institutions, employers, workers, forest owners, educational institutions, insurance agencies, and others. This concept calls for continuing professional education and worker education, training, and certification of working skills. Apart from increasing the level of forest work safety and lessening the consequences of accidents at work, the implementation of safety culture in terms of improving the forestry techniques also implies: Þ Higher professionalism and restoration of the image marred by a large number of accidents and frequent employment of unqualified workforce, Þ Opportunities for further development of organisation of work and improvement in other aspects of forest work, such as economic efficiency, ecological acceptability, energetic efficiency, etc. To contribute to the increased quality and efficiency of forest work, as well as to improve safety and health, two programmes are currently under way at the Faculty of Forestry of Zagreb University: Þ Evaluation of forest workers’ work techniques, Þ Investigation of the foundations for the establishment of forest contractor licensing.

Fig. 1 Key participants and elements in the establishment of safety culture in forestry Slika 1. Pregled klju~nih sudionika i elemenata pri uspostavi kulture sigurnosti u {umarstvu 48

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Evaluation of individual elements of work techniques conducted for the most typical jobs (cutters, tractor drivers, chopper setters) since 2000, has proved to be a very objective method for identifying critical points in work processes and a reliable indicator of points that require correction and improvement through training and practice (Martini} and Matijevi} 1999, Martini} 2006). The legal framework for certification and licensing of forest workers was first recognized as a legal commitment in the Forest Act of 2005 (Anon. 2005). In recent years the initial groundwork has been made for a possible institutional framework of the licensing system ([por~i} and Martini} 2005, [por~i} 2003). However the beginning of licensing has been postponed until by-laws are passed regulating in detail the criteria and organisation of licensing.

3. Increasing energetic efficiency and ecological acceptability: lower consumption of energy sources dangerous for the environment and a gradual introduction of biofuels and biolubricants – Pove}anje energetske u~inkovitosti i ekolo{ke povoljnosti: manja potro{nja energenata {tetnih za okoli{ i postupno uvo|enje biolo{kih goriva i maziva Energy consumption has always represented a major share in the cost of forest production, and particularly in the cost of mechanised forest operations. Significant ecological consequences and harmful effects of fuel and lubricant consumption on the environment cannot be neglected either, especially in areas of intensive use of mechanisation (Martini} 2000, Augu{tin et al. 2000, Martini} and [por~i} 2005, Martini} et al. 2001). Mechanical and chemical damage to the environment can be, and often is, very serious. According to research by SkogForsk1 (News 1/ 2006), fuel consumption per m³ of felled and transported timber in the period 1985–2005 dropped from 5.4 to 3.7 litres/m³ or approximately by 30%. This was achieved by improving mechanisation, i.e. by replacing heavy machinery with lighter one, improving the engine, and also by improving the extraction system and further transport. Efforts to cut down on energy consumption are continuing, especially in

1 2

the field of optimising hydraulic systems and using alternative fuels and lubricants. It is expected that the current substantial difference in the price of traditional mineral fuels and lubricants and those of biological origin (biodiesel, bio-oils and biolubricants) will decrease significantly in the near future. Efficiency will be additionally increased by better durability and cheaper methods of waste disposal (Makkonen 2000, Skoupy 2000). In Croatia, the price of diesel fuel rose by 2.5 times between 2000 and 2006 alone. For example, if annual consumption of diesel fuel in the company »Hrvatske {ume« d.o.o.2 (Table 1) decreased by 20%, annual savings would amount to 1.2 million Euro! In view of the fact that countries with developed forestry have already adopted strategies of a gradual increase in the share of alternative energy sources, the development and implementation of a strategy for lower fuel consumption and decreased dependence

Table 1 The quantity of consumed fuel in the state company »Hrvatske {ume« d.o.o. Zagreb in 2006 Tablica 1. Procijenjene koli~ine utro{enoga goriva u dr`avnoj tvrtki Hrvatske {ume d.o.o. Zagreb u 2006. Type of fuel Vrsta goriva

Quantity Koli~ina

Cost – Tro{ak

L

%

Diesel fuel Dizelsko gorivo

4 800 000

51,60

Eurodiesel Eurodizel

2 700 000

29,02

Diesel, total Dizel, ukupno

7 500 000

80,62

MB super 95 MB super 95

1 000 000

10,75

MB Eurosuper 95 MB eurosuper 95

650 000

7,00

MB super 98 MB super 98

150 000

1,61

1 800 000

19,36

2 500

0,2

9 302 500

100,00

Engine gasoline, total Motorni benzini, ukupno Other – fuel oil Ostalo – lo`-ulje Overall Sveukupno

106 Kn 106 EUR

43

5,85

12

1,63

55

7,48

Swedish Institute of Forest Research – Švedski institut za šumarska istra`ivanja Hrvatske šume d.o.o. Zagreb (state owned trade company that manages 1,991,537 ha of state forests – Hrvatske šume d.o.o. Zagreb (trgova~ko društvo u dravnom vlasništvu koje gospodari s 1 991 537 ha dravnih šuma)

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on traditional fuels should also be advocated in Croatia3. In order to do this, we should: Þ Optimize the energetically most demanding work processes (extraction, further transport and forest road construction) with mathematical modelling in both planning and execution, Þ Stimulate savings by using information technologies to monitor energy fuel consumption per place of consumption, Þ Provide machinery with engines using high-quality fuel. As to gradual introduction of biofuels and biolubricants, their use would initially be justified in places where there is a risk of threat to areas of special ecological importance, such as parts of the national ecological network or habitats within the NATURA 2000 network. Higher costs of such projects should be co-financed or subsidised by the Environmental Protection and Energy Efficiency Fund.

4. Developing management and financial instruments for modern technologies: advanced systems and state incentives – Razvoj menad`menta i financijskih instrumenata za moderne tehnologije: napredni poslovni sustavi i dr`avni poticaji Research conducted by the European Forest Institute (EFI) within the INNOFORCE programme has shown a very low level of innovative processes in the forestry of transitional countries (Rametsteiner and Yadlapalli 2004, Rametsteiner et al. 2004). Innovations are divided into: organisational innovations (39%); technological innovations (14%); creating new wood and non-wood products (18%) and services (20%). The basic prerequisite for the above innovations is the development of entrepreneurship in forestry. In view of the specific features of forestry (long-term production cycle, specific jobs and the need for special equipment, etc.), entrepreneurial initiatives in forestry must receive broad support by the society, especially in the part relating to the private forest segment. This includes both advisory assistance and instruments of state financial support.

3

In order to encourage entrepreneurship in the forestry of Croatia, it is necessary to: Þ Establish an information and counselling system, Þ Provide targeted training for specialist services and possible entrepreneurs in the field of business opportunities evaluation and preparation of entrepreneurial projects, Þ Strengthen competent administrative bodies in counties, Þ Develop a system of state incentives. Croatia needs a well-developed system of incentives and support in forestry equal to that in e.g. tourism, agriculture and artisanship. Financial instruments should include non-returnable funds (one-time or multiple financial supports), loans with subsidised interest, tax benefits, etc.). Similarly, the Environment Protection and Energy Efficiency Funds should be available to forestry sector under prescribed conditions as well as funds collected for non-commercial forest functions as defined in the Forest Act (Anon. 2006a). Related to the improvement of techniques and technologies, non-returnable funds should be allocated to: Þ Education and training of private forest owners, Þ Technological-technical categorisation of working conditions, Þ Pilot-projects of testing alternative and cost-saving technologies, Þ Production of an investment strategy into technical infrastructure, Þ Targeted research. Subsidised loans should be allocated to the: Þ Development of a system of education, training and licensing, Þ Establishment of training centres for the use of forestry machines, Þ Acquisition of 4E mechanisation. Tax benefits should be secured primarily for the acquisition of measuring and safety equipment and for the acquisition of mechanisation whose production is not profitable or is impossible to organize in Croatia.

Croatia undertook to include 5.75% of alternative fuels in the overall fuel consumption by 2010 – Hrvatska se obvezala na 5,75 % udjela alternativnih goriva u ukupnoj potrošnji goriva do 2010. godine

50

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Table 2 Tasks related to the development of forest-based technologies (according to NFPS, 2002) Tablica 2. Zadaci vezani uz razvoj tehnologija u {umarstvu (prema N[PS 2002) Label Oznaka A2.2. A2.3. A2.4. B5.1. B5.3.

Description of Activities Opis aktivnosti Supporting measures for ensuring personnel education in the implementation of 4E technologies Potpora mjerama za osiguravanje potrebne izobrazbe kadrova za provedbu 4E tehnologija Developing financial initiatives for support in implementing environmentally-friendly technologies (e.g. bio-oils, yarders) Razvijanje financijskih inicijativa za potporu u provedbi tehnologija koje nisu {tetne za okoli{ (npr. bioulja, `i~are) Improving work techniques and safety at work through training, evaluation and certification Unapre|ivanje radne tehnike i sigurnosti pri radu osposobljavanjem, ocjenjivanjem i potvr|ivanjem Defining conditions and criteria for licensing forestry contractors Definiranje uvjeta i kriterija za licenciranje ugovaratelja u {umarstvu Establishing and implementing a licensing system for forestry contractors Uspostavljanje i provo|enje sustava licenciranja za ugovaratelje u {umarstvu

Priority* Prioritet* I II I I I

* to be implemented in the period – obveza provedbe u razdoblju: I. (2003–2006), II. (2006–2008), III. (2008–...)

5. To what extent is the development of forestry technologies and techniques supported by research? – Koliko istra`ivanjima podupiremo razvoj {umarskih tehnologija i tehnika? Research is undoubtedly one of the principal triggers for changes and progress in different forestry fields and technologies. The most important contributions are usually the result of targeted research. The question is whether investigations in Croatia, in terms of forestry techniques, address those issues that have been defined as priority. Are there more important issues that are not investigated? What is our position in relation to European research priorities? If we assume that research priorities in the forestry sector of Croatia should be closely linked with priority activities set down in the National Forestry Policy and Strategy (NFPS), then they refer to two segments (Anon. 2003): Þ a) Introduction of 4E (ecological, ergonomic, economic, energetic) technology in forestry and Þ b) Certification and licensing of forest contractors. Activities related to the achievement of these goals are shown in Table 2. A special activity within the NFPS (National Forestry Policy and Strategy) is the establishment of a body within the Ministry of Forestry, which would be responsible for coordinating priority research needs and findings. Regrettably, although the NFPS was adopted five years ago, this body has not been established yet. Croatian Journal of Forest Engineering 28(2007)1

In order to review European research priorities in the forestry sector, we will list the main fields of research contained in the document The Strategic Research Agenda (SRA). The Agenda, established within the VISION 2030 project – The Forest-Based Sector Technology Platform (FTP), was drawn up by the most eminent forestry institutions and organisations involving over 1,000 representatives of the forestry sector from 20 European countries (Anon. 2006A, Anon. 2006B). The SRA singled out five strategic goals that represent key research areas in the following decades: Þ Development of innovative products for changing markets and customer needs, Þ Development of intelligent and efficient manufacturing processes, including reduced energy consumption, Þ Enhancing availability and use of forest biomass for products and energy, Þ Meeting the multifunctional demands on forest resources and their sustainable management, Þ Placing the forestry sector in a social perspective. Research priorities within the second strategic goal »Development of intelligent and efficient manufacturing processes, including reduced energy consumption« include: Þ Advanced technologies for primary wood processing (cutting, processing and transport), Þ New technologies for optimizing the production of wood products, Þ Reducing energy consumption and achieving energy efficiency in all production stages,

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Þ Continuous rise in the efficiency of production with decreased environmental impacts, Þ Stimulating the production of biomass-based thermal and electrical energy. On the other hand, the currently investigated issues of forest techniques in Croatia are contained in a group of projects undertaken by the Faculty of Forestry and the Forestry Institute in Jastrebarsko for the company Hrvatske {ume d.o.o. Zagreb, for the period 2006–2010. The research tasks include: Þ Establishing slash stacking with machinery methods, Þ Forest biomass and harvesting technologies, Þ Optimizing a primary forest road network in hilly and mountainous areas using modern work technologies, Þ Knowledge of and attitudes on biomass as a source of energy, Þ Planning secondary forest roads (strip roads and skid trails) in hilly-mountainous areas, Þ Drawing up a feasibility study for investments into thermal power stations, Þ Licensing and certification aimed at achieving European standards of safety and quality of forest work, Þ Evaluating business efficiency of organisational forestry units using a non-parameter model, Þ Environmentally friendly forest techniques, Þ Environmentally friendly technologies in forest management according to valid international norms, Þ Classification of forest soils according to field conditions, management methods and criteria for the selection and application of the most suitable techniques and technologies. The second group of projects is financed by the Ministry of Science, Technology and Sport (MSTS). Among the 38 approved and financed projects for the research period 2006–2009, only 5 are directly linked with forest technologies: Þ Modern technologies of planning and designing forest road networks, Þ Ecological, energetic and ergonomic evaluation of forest machines and equipment, Þ Environmentally-friendly forest harvesting, Þ Contribution to the study of forest biomass use, Þ Improving forest-harvesting technologies aimed at providing protection to the environment and workers.

52

Even a very general comparison of national and European research needs with the ongoing research activities in Croatia shows the following: Þ The absence of a systematic and comprehensive »research response« to defined priority needs, Þ Some priority areas are well »covered« with a number of complementary research tasks, Þ A part of research topics is only segmentarily and/or partially covered by broadly defined research tasks and projects, Þ Some research priorities are completely exempt from the ongoing research programmes and are not investigated at all; e.g. development of new products, lower energy consumption, optimisation of work processes and others. Further to the above it can be concluded that the existing research programme in Croatia is not sufficient either in terms of the scope of fields and topics or the number of projects and tasks to guarantee a more significant improvement of forest techniques and technologies. On the other hand, with regard to the number of scientists-researchers who are potential leaders of research activities in forest techniques in Croatia, the only certainty seems to be the possibility of their cooperation and involvement in international and multidisciplinary projects, which will provide acceptable solutions for home use too. Unfortunately, there has been no regional cooperation among researchers of forest techniques to date.

6. References – Literatura Anon., 2003: Nacionalna {umarska politika i strategija (NN 120/03). Anon., 2005A: Zakon o {umama (NN 140/2005). Anon., 2006A: Forest-Based Sector Technology Platform (2006): A Strategic Research Agenda for Innovation, Competitiveness and Quality of Life. European Commission, p. 1–28. Anon., 2006B: Forest-Based Sector Technology Platform (2006): A Strategic Research Agenda – Annex: Extended Descriptions of Research Areas. European Commission, p. 1–32. Augu{tin, H., Dekani}, S., Martini}, I., Sever, S., 2000: Okoli{no ne{kodljive hidrauli~ne teku}ine za {umarske strojeve – stanje i izglednost. Meh. {umar. 25(1–2): 41–57. ILO, 1998: Safety and health in forestry work – An ILO Code of practice. ILO, Geneva 1998, 1–166. Makkonen, I., 2000: Shut off system to reduce hidraulic oil leakage from forestry machines. FERIC (14)1: 1–8. Croatian Journal of Forest Engineering 28(2007)1


Development of a new concept for improvement of forest techniques in Croatia ... (47–54)

Martini}, I., 1998: Stanje i razvoj izvo|enja radova u Hrvatskoj neovisnim poduzetnicima. Meh. {umar. 23(1): 7-13. Martini}, I., Matijevi}, G., 1999: Ocjena radne tehnike {umarskih radnika – metode i rezultati prethodnih istra`ivanja. Meh. {umar. 24(1–2): 13–29.

I. MARTINI] et al.

Croatia. International symposium »Wood Quality, Technologies, Man and Work in Forest», October 24–25, 2006, Ljubljana, Slovenia. Rametsteiner, E., Yadlapalli, L., 2004: Fostering Innovation and Entrepreneurship. EFI 12(2): 3–6.

Martini}, I., 2000: Koliko smo blizu ekolo{ki prihvatljivoj uporabi mehanizacije u {umarstvu? [umarski list 124(1–2): 3–13.

Rametsteiner, E., Weiss, G., Kubeczko, K., 2004: Innovation and Entrepreneuship in Forestry in Central Europe. EFI Report series.

Martini}, I., Juri{i}, M., Hengl, T., 2001: Some ecological effects of machinery utilization in forestry. Strojarstvo 41 (3–4): 123–129.

Skoupy, A., 2000: Biodegradable oils in the operation of forest machines. Proceedings of Division 3, IUFRO Congress Kuala Lumpur, p. 191.

Martini}, I., [por~i}, M., 2005: Ekolo{ko gledi{te odr`avanja mehanizacije u {umarstvu. [umarski list 129(1–2): 19–28.

[por~i}, M., 2003: Uspostava modela potvr|ivanja izvoditelja {umskih radova. Magistarski rad, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–100.

Martini}, I., 2006: Health protection and safety in forestry work during the transition period of the forestry sector in

[por~i}, M., Martini}, I., 2005: Model licenciranja izvoditelja {umskih radova. [umarski list 129(7–8): 375–385.

Sa`etak

Razvoj novoga koncepta za unapre|ivanje {umarske tehnike u Hrvatskoj – podru~ja mogu}ega doprinosa U ~lanku se raspravlja o mogu}em konceptu unapre|ivanja {umarske tehnike u Hrvatskoj kao odgovoru na pove}ane ekolo{ke, socijalne i ekonomske obveze i izazove. Kao klju~na sastavnica novoga koncepta i mogu}a podru~ja zna~ajnoga doprinosa razmatraju se postizanje kulture sigurnosti u {umarstvu, pove}anje energetske u~inkovitosti uz manji utjecaj na okoli{, razvoj inovacija i poduzetni{tva te ve}i doprinos istra`iva~koga rada. Rizik pojave nesre}a i ozlje|ivanja {umskih radnika u Hrvatskoj u prvom su redu posljedica nezadovoljavaju}e razine organizacije i radne tehnike u izvo|enju radova, pri ~emu se glavni uzroci nalaze u manjkavoj primjeni stru~nih znanja i slabostima osposobljavanja izravnih izvoditelja {umskih radova. U tom kontekstu kultura sigurnosti u {umarstvu razumijeva zajedni~ko djelovanje dr`avnih institucija, poslodavaca, radnika, vlasnika {uma, obrazovnih institucija, osiguravaju}ih agencija i drugih. U sredi{te unapre|ivanja {umarske tehnike stavlja se kontinuirano osposobljavanje stru~noga osoblja te izobrazba i potvr|ivanje radne vje{tine radnika, posebno rukovatelja {umskom mehanizacijom. Kao doprinos pove}anju kvalitete i ekonomi~nosti {umskoga rada, ali i pobolj{anju sigurnosti i zdravlja, na [umarskom fakultetu Sveu~ili{ta u Zagrebu od 2000. godine provodi se ocjenjivanje radne tehnike {umskih radnika. Jednako va`an dio pobolj{anja kvalitete i sigurnosti pri {umskom radu prepoznaje se u obveznom licenciranju izvoditelja {umskih radova. Drugi va`an doprinos unapre|ivanju {umarske tehnike smatra se pove}anje energetske u~inkovitosti i ekolo{ke povoljnosti. Osim zna~ajnih tro{kova u {umarskoj proizvodnji, uz potro{nju energenata vezan je i nezanemariv utjecaj na okoli{, posebno pri odr`avanju mehanizacije i u podru~jimna njezine intenzivne primjene. U Hrvatskoj je od 2000. do 2006. godine cijena dizelskoga goriva pove}ana 2,5 puta. Ako bi se godi{nja potro{nja dizelskoga goriva samo u Hrvatskim {umama d. o. o. smanjila za 20 %, dobile bi se godi{nje u{tede u iznosu od 1,2 milijuna eura! Po uzoru na ~lanice Europske unije i Hrvatskoj se sugerira izrada i provedba strategije energetske u~inkovitosti i smanjenje ovisnosti o klasi~nim gorivima i mazivima. Za iskorak u razvoju {umarskih tehnika nu`an je razvoj poduzetni{tva i financijskih instrumenata u {umarstvu, jednak onomu koji sada postoji, primjerice, u turizmu, poljoprivredi i obrtni{tvu. Pritom bi financijski instrumenti trebali uklju~ivati poticaje, kapitalna bespovratna sredstva, kredite sa subvencioniranom kamatom, carinske olak{ice i drugo. Jednako tako {umarskom bi sektoru trebala biti dostupna sredstva Fonda za za{titu okoli{a i energetsku u~inkovitost te sredstva prikupljena za op}ekorisne funkcije {uma. I u Hrvatskoj se o~ekuje da istra`ivanja budu jedan od glavnih pokreta~a promjena i unapre|ivanja razli~itih podru~ja {umarske djelatnosti, pa tako i tehnologija i tehnika. Kako su najzna~ajniji doprinosi redovito rezultat ciljanih istra`ivanja, postavljaju se pitanja: Istra`ujemo li u Hrvatskoj, kad su u pitanju {umarske tehnike, ono {to

Croatian Journal of Forest Engineering 28(2007)1

53


I. MARTINI] et al.

Development of a new concept for improvement of forest techniques in Croatia ... (47–54)

je definirano kao prioritetno? Ima li va`nih tema koje ne istra`ujemo? Gdje smo u odnosu na europske istra`iva~ke prioritete? Na temelju okvirne usporedbe nacionalnih i europskih istra`iva~kih potreba s teku}im istra`ivanjima u Hrvatskoj ocjenjuje se kako postoje}i istra`iva~ki program nije dostatan za zna~ajnije unapre|ivanje {umarske tehnike i tehnologije, pri ~emu se rje{enje vidi u uklju~ivanju hrvatskih znanstvenika u me|unarodne i u multidisciplinarne istra`iva~ke projekte. Klju~ne rije~i: {umarstvo, {umarske tehnike, zdravlje i sigurnost pri {umskom radu, potro{nja goriva, istra`ivanja

Authors’ address – Adresa autorâ:

Received (Primljeno): January 8, 2007 Accepted (Prihva}eno): March 2, 2007

54

Assoc. Prof. Ivan Martini}, PhD. e-mail: martinic@sumfak.hr Assoc. Prof. Vencl Vondra, PhD. e-mail: vondra@sumfak.hr Mario [por~i}, MSc. e-mail: sporcic@sumfak.hr Forestry Faculty of Zagreb University Department of Forest Engineering Sveto{imunska 25 HR-10 000 Zagreb CROATIA Croatian Journal of Forest Engineering 28(2007)1


Subject review – Pregledni ~lanak

Fatal accidents in forestry in some European countries Jaka Klun, Mirko Medved Abstract – Nacrtak Forest work is considered one of the most dangerous occupations in the world. The present article compares fatal accidents occurring at professional and non-professional work in terms of the amount of removals. The data covering the years from 1980 to 2004 are dealt with by 5-year periods. For Slovenia and Austria, all five periods are compared, for Switzerland four, whereas for Germany, Finland, Sweden and Croatia fewer periods are dealt with. The accident frequency is expressed in the number of fatalities per 1 million m3 of gross removals. Absolutely the highest frequency (9.52) was established at non-professional work in Slovenia during the period 1990–1994, the lowest (0.03) at professional work in Sweden (2000–2004) and Finland (1995–1999). In the last period (2000–2004), the highest number of fatal accidents at professional work was recorded in Switzerland (1.00). At non-professional work, on the other hand, the highest number of fatalities occurred in Slovenia (7.27), which is almost five times as many as in Austria and Switzerland. In all countries, however, a downward trend of fatal accident frequency has been noted. The most successful, as far as total number of fatalities is concerned, is Sweden. In Switzerland and Austria, the accident frequency has been cut by half, whereas in Slovenia no progress has been noted in this respect. The number of fatalities is an important indicator of mastering the risks during forest work as well as of the efficiency and integrity of measures implemented by separate countries in their attempts to provide for safety at forest work. Keywords: forest work, fatal accident, European countries

1. Introduction – Uvod In the last twenty-five years, the development of work safety has also been reflected in the data on most serious forest work accidents. The data on fatal deaths are not tedious numbers, but indicate the role of education, training, protection and improvement of personal safety equipment, technological development, organisation and implementation of forest work. In spite of the great progress of techniques and information technology, the forest activities remain one of the most hazardous professional and particularly non-professionals activities in the majority of the countries worldwide. Forest work is not only carried out by trained professional workers, but also by professionally less qualified forest owners, their relatives and acquaintances. Fatal accidents are registered and filed with grater accuracy than other work accident. The statistics of accidents occurring in the sphere of non-professional implementation of Croatian Journal of Forest Engineering 28(2007)1

forest work are more incomplete than those occurring during professional work. Monitoring of accidents in forestry and comparisons between separate countries are very complex tasks owing to the differences in their domestic legislations, organisation in the sphere of the workers’ social and health security, as well as different methodologies and manners of accident reports. Even more incomplete are registers of work accidents involving non-professional workers. On the basis of the data supplied by separate countries, forestry accounts for a relatively high share of fatal accidents, with the frequency characteristic of mining and building industries, owing to the length of workday, seasonal and meteorologically conditioned work, distant and isolated work places. Monitoring and analysing accidents in the same branch of industry and in a longer period of time indicate certain trends of increasing safety in professional and non-professional implementation of work.

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The consequences of accidents are also a significant item in the national economic accounts. Joint European statistics enables comparisons to be made for individual countries as to their success in the introduction of new approaches, since forest work safety and health protection is one of the social aspects of sustainable forest management. Social protection of the forestry sector workforce is one of the indicators of sustainability in the sixth criterion for sustainable forest management, as stipulated by the Ministerial Conference on the Protection of Forests in Europe (Mcpfe 2003). In the past, the International Labour Organization established that forest workers were involved in accidents three to four times more frequently than agricultural workers (ILO). The conclusion that forest work is amongst the most risky and dangerous occupations was drawn in the 1980s in Finland (National Board of Labour Protection 1988) and in the United States (Leigh 1987) on the basis of death rate for forest workers in comparison with other professions. In the 1990s, the situation did not change in the States, for the accident death rate amounted to 4.5 on average per 100,000 employed for all professions (Herbert and Landrigan 2000). On the basis of similar studies and international comparisons from the late 1970s to 1990s some countries developed various systems of protection, training, work process organisation, personal protective equipment and motivation approaches, which in a relatively short time contributed to a reduced number of accidents at professional and, with certain adjustments, non-professional forest work.

The objective of the research of fatal accidents at professional and non-professional forest work is to identify the sources and quality of data as well as to establish, on their basis, the differences between the selected countries in their number and occurrence in view of the conducted work. We presuppose that the differences between the countries are the result of different approaches in the provision of safety and health protection as well as of the earnestness in dealing with statistical data on accidents occurring at forest work. We presume that due to the differences in the manner of forest management and introduction of modern technologies in wood production, the number of fatal accidents during forest work is falling. The third hypothesis is that the collected data on fatal forest work accidents during a longer period of time indicate trends of accidental safety in the professional and non-professional conduct of work.

2. Work method â&#x20AC;&#x201C; Metoda rada Comparison has been made between accidents occurring at professional and non-professional work. We assumed that the implementation of forest work in forests owned by the state, companies and big proprietors is within the domain of professional forest workers, whereas the production in smaller privately owned forests is in most cases carried out as non-professional work. On this basis, we compared accidental safety in individual countries at professional and non-professional work as well as the amount of work carried out.

Table 1 Forest and human resources in forestry sector in the countries selected for comparison (Gfra 2005) Tablica 1. [umski i ljudski resursi u {umarskom sektoru odabranih zemalja (Gfra 2005) State Dr`ava Slovenia Slovenija Switzerland [vicarska Austria Austrija Germany Njema~ka Sweden [vedska Finland Finska Croatia Hrvatska

56

Total land area Ukupna povr{ina

Forests and woodland [ume i {umsko zemlji{te 1000 ha

Private forests Privatne {ume

Employees in forestry sector Zaposleni u {umarskom sektoru 103 employees â&#x20AC;&#x201C; 103 zaposlenika

Removals Godi{nji etat 1000 m3

2,014

1,309

938

3

3,153

3,955

1,288

397

7

6,958

8,273

3,980

3,189

8

20,127

34,895

11,076

5,230

70

60,770

41,162

30,785

23,492

17

76,980

30,447

23,302

15,487

24

64,300

5,592

2,481

462

10

4,950

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Table 2 Available data for accidents and removals by periods Tablica 2. Dostupnost podataka o nesre}ama i obujmu sje~e prema vremenskom razdoblju

Country Dr`ava

Slovenia Slovenija Switzerland [vicarska Austria Austrija Germany Njema~ka Sweden [vedska Finland Finska Croatia Hrvatska

Available data Professional forest work Dostupnost podataka Profesionalni {umski rad Accidents Removals Nesre}e Etat

Available data Non-professional forest work Dostupnost podataka Neprofesionalni {umski rad Accidents Removals Nesre}e Etat

1980–2004 1980–2004 1981–2004 1980–2004 1984–2004 1984–2004 1984–2004 1980–2004 1980–2004 1980–2004 1980–2003 1980–2004 1999–2004 1993–2004 1980–2004 1990–2004 1985–2004 1980–2004 1989–2004 1980–2004 1980–2003 1980–2004 1983–2004 1983–2004 1996–2004 1994–2004

Not available 1994–2004 Nedostupni

The selection of countries, whose statistics of accidents at work is here compared, was not random. As the frequency of accidents occurring during forest work is influenced by numerous natural and social factors, we selected the countries with very different development of forest management. In Table 1, some basic statistical data are presented for forestry sectors of the countries compared in our research: Austria, Switzerland and Slovenia, which are geographically connected by the Alps, the neighbouring Croatia with a minor share of privately owned forests, Germany, which spreads from the Alps to the North Sea, and Scandinavian countries Finland and Sweden. The data were analysed on fatal accidents occurring during professional and non-professional work. For comparison, official data were used of national statistics, statistics of insurance companies for farmers and forest proprietors, and data of insurance companies for workers. The sources of data differ between the studied countries in terms of the organisational arrangement of the national statistics and the existence of specialised insurance and interoperational organisations. In defining fatalities occurring at forest work, we followed the ESAW-Eurostat methodology of the European Statistical Office (Eurostat 2001). Fatal accident at work is defined as an accident owing Croatian Journal of Forest Engineering 28(2007)1

J. KLUN and M. MEDVED

to which the victim of the accident died within a year of the event (in Germany, the acknowledgement of fatalities is limited to 30 days after the accident, whereas Austria and Sweden do not deal with fatalities, if the victim was recognised as permanently incapable of work prior to death). Only accidents as direct events in a working process at forest work are taken into account. Comparative analyses of the total number of accidents in a country were only made if all data were available to us (Table 2). Owing to the possible seasonal impacts of meteorological or socio-economic conditions and in order to get a clearer idea of the matter, the accidents that occurred in individual countries were compared by 5-year periods. All 5-year periods from 1980 to 2004, where data on accident safety and removals were obtained, were taken into consideration. Roundwood removals were dealt with for all countries in gross values published by the official statistics. As far as data for Slovenia are concerned, 40% share of the production in state-owned forests was taken into account for the years 1992 and 1993. The sources of data on fatalities occurring during professional forest work were the statistical yearbooks for the period 1996–2006. Concerning non-professional work in Slovenia, average number of fatalities in the period 1981–1992 was taken into consideration.

3. Results – Rezultati Initially, the results show collation for professional workers, followed by accidents occurring at non-professional work and, finally, by joint collation of all fatalities by individual countries and periods.

3.1 Fatalities at professional forest work – Smrtni slu~ajevi pri profesionalnom {umskom radu The number of accidents occurring at professional work has been reduced in all countries under consideration. In view of the first period, the number of fatalities among professionally trained forest workers was reduced by half at the least. The most distinct decrease was recorded in Sweden and particularly in Finland. An exception is Croatia, where more accidents were recorded in the last period than in the period prior to it. In Slovenia, too, fewer accidents occurred in the period 1990–1994 than after 1995. Figure 1 shows average annual number of fatalities in separate 5-year periods by individual countries. In all the countries compared here, the roundwood removals are increasing. The number of fatalities among professional forest workers in Croatia

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Fatal accidents in forestry in some European countries (55â&#x20AC;&#x201C;62)

Fig. 1 Average number of fatalities at professional forest work Slika 1. Prosje~an broj smrtnih slu~ajeva pri profesionalnom {umskom radu increased as well, i.e. by more than twice, while the number of fatalities among professional forest workers in Scandinavian countries in the last two 5-year periods was lower than 0.1 fatality per 1 million m3 of roundwood removals. In view of the results concerning the frequency of fatal accidents in the last period, the following countries can be classified in the same group: Slovenia, Austria, Switzerland and Croatia. Much better safety has been achieved in Germany, and the best in Scandinavia (Sweden and Finland). In the first group, one

fatality occurred per a little more than 1 million m3 of gross removals, in Germany per 7 million, and in Scandinavia per more than 30 million m3 of roundwood removals.

3.2 Fatalities at non-professional forest work â&#x20AC;&#x201C; Smrtni slu~ajevi pri neprofesionalnom {umskom radu Figure 2 shows the frequency of fatalities occurring at non-professional forest work. In this respect, the safety is constantly improving as well. In the

Fig. 2 Average number of fatalities at non-professional forest work Slika 2. Prosje~an broj smrtnih slu~ajeva pri neprofesionalnom {umskom radu 58

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Fatal accidents in forestry in some European countries (55–62)

period 2000–2004, the number of fatal accidents at non-professional work only increased in Slovenia. In the group of five countries, the non-professional work accidents are distinctly characteristic of Slovenia. Apart from our country, data for the entire period 1980–2004 are only available for Austria. Here, the accident frequency was cut by half from the initial 3 to 1.5 fatalities per 1 million m³ of gross removals. In Slovenia, the number of fatalities was reduced from 8.6 to 7.3. Compared with Austria, we had 2.8 times higher frequency a quarter of a century ago, in the last period 4.8 fatalities more than Austria. In Switzerland, the frequency has been reduced by 2.5 times in the last twenty years. Quite successful in the last 15 years were also in Germany and Sweden, where the frequency has been reduced by 1.7 and 3.3 times, respectively.

3.3 Total amount of fatalities per separate countries – Ukupan broj smrtnih slu~ajeva po zemljama Data on fatalities at professional and non-professional forest work were integrated in 5-year periods and the frequency of accident occurrence calculated in view of the amount of gross removals. Comparisons between individual countries are shown in Figure 3. For Sweden, we even have a datum more in the series, as a total number of accidents was available to us for the period 1985–1989. Apart from Slovenia and Croatia (the latter is not included in Figure 3, as we have no data for nonprofessional work there), the compared countries

J. KLUN and M. MEDVED

had falling trends as far as the number of fatalities is concerned. At the end of the studied periods, Austria, Switzerland and Germany reduced the number of fatal accidents to less than 1.2 per 1 million m3 of gross removals. In the 5-year period, Slovenia remained, with ca. 5 dead per 1 million gross removals, at the same level as a quarter of a century ago. In the studied period, the average values of the fatal deaths frequency per 1 million m3 gross removals were 1.84 for Austria, 4.90 for Slovenia and 1.94 for Switzerland, whereas in Sweden the value was 0.11 fatalities per 1 million m3 during the 15-year period after 1988. In the period 1999–2004, Germany had on average 0.67 fatalities per 1 million m3 of gross removals.

4. Discussion and conclusion – Rasprava i zaklju~ci In the present article, a comparison is made between the number of fatalities that occurred during professional and non-professional forest work in a longer period of time, in which major organisational and technological changes in wood production took place. Statistical data for the period after 1980 in Slovenia, Austria, Switzerland, Germany, Finland, Sweden and Croatia are also analysed. While comparing the numbers of accidents and fatal accidents occurring at professional and nonprofessional forest work between different countries, we unavoidably stumble upon various limitations that reduce the accuracy of the compared data. The reasons are to be looked for in the legislation con-

Fig. 3 Average number of fatalities regarding gross roundwood removals by separate periods and countries Slika 3. Prosje~an broj smrtnih slu~ajeva prema razdobljima i zemljama Croatian Journal of Forest Engineering 28(2007)1

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cerning social security and the manner of keeping accident records in individual countries, as well as in their publishing in publicly accessible reports. As data for a relatively long period are compared, we can follow, in spite of possible incomplete data, the trends in safety and health protection development as far as forest work is concerned. The data on accidents were linked with data on work effects, which is probably the only acceptable way of showing the differences from the aspect of international comparisons (Poschen 1993). With the selection of the countries in our research we have limited ourselves to certain EU members, which are liable to respect the increasingly uniform methodology of collecting and passing on the data. On the same methodological basis, the comparisons will be increasingly easier. We also included Croatia as a candidate country to join the EU and Switzerland, which elaborately records and processes the data on forest work accidents in the compared countries. The second characteristic feature of the selection of the countries compared herewith is their natural diversity and different manners of forest management as well as their development of wood production technologies. Rapid and economically significant development of wood production is characteristic of Austria, as well as introduction of machine logging in difficult conditions and a solid organisational arrangement by forest owners and forestry services. Switzerland has reached a similar development in forestry doctrine and the manner of conducting forest work, except that it has a quite different social and political history and a different strategy concerning the reduction of forest work accidents than Slovenia. Owing to its geographical size, the level of decisionmaking in the sphere of forestry at the level of federal provinces and the process of uniting, Germany expresses a great diversity of natural conditions, forest management as well as monitoring forestry statistics in the sphere of accidents. Characteristics of Finland and Sweden are their highly developed forestry systems, high share of machine logging and skidding, entrepreneurially organised forest proprietors, high degree of safety and health protection at forest work and multinational forestry companies. Croatia, on the other hand, is still preparing to join the EU and has retained a high share of state forests as well as centrally organised forest management. The increased numbers of accidents and fatalities as the result of disastrous damages caused by weather, including powerful snow- and wind-breaks are quite characteristic of certain years. In Germany and Switzerland, a 10% increase in fatalities was recorded in 1990 due to the storms »Wiebke« and »Vivian«, and in 2000 due to »Lothar« (Ammann et al. 2002,

60

Fatal accidents in forestry in some European countries (55–62)

Strack 2006). Sweden, which had three fatalities on average at non-professional forest work and one fatality at professional work in the period 2000–2004, was in 2005 hit by the storm »Gudrun«. During the production of wood from the affected stands, 141 accidents were reported, claiming more than three days of sick leave. As a result of accidents, seven non-professional and three professional forest workers lost their lives (Blom 2006). These salient data are somewhat levelled in comparisons by 5-year periods. The events after 2004, however, have not been included in our comparisons. Fatal accidents that occur at forest work are the most reliable data in the collected and processed accident statistics and good indicators of trends in development of forest work safety. Their number fall most obviously with the speed of introduction and share of machine logging and skidding, which is confirmed by the introduction of machine logging and hauling in view of the situation of accident safety in Scandinavian countries (Axelsson 1998). The last 5-year period has been marked in Austria (Pröll 2003, Pröll 2005) and Germany (Nick 2005) with increasingly higher share of machine logging and increase in the number of logging machines. In this period, the downward trend in the number of accidents and fatalities continues. As far as professional forest work is concerned, a downward trend in the number of accidents and fatalities and an upward trend in the effects of work at the same time has been noted in all the countries compared here. For Slovenia, the data show a considerable reduction in the number of fatalities among professional workers during the transition of our economic system from 1990 to 1994. In this period, the number of forestry employees was greatly reduced, and there was also a setback in felling control. In Croatia, the number of deaths at professional work increased in the last period. Concerning non-professional forest work, the effects of measurements as part of the preventive accident policy show themselves in the long run. The last 5-year period in our study (2000–2004) puts Slovenia, with its more than 7.5 deaths per 1 million m3 of gross removals, in the first place. Austria, Germany and Switzerland have less than 2.5 deaths and Sweden less than 0.1 deaths per 1 million m3 of gross removals. For Croatia, we have no data on accidents and fatalities occurring at forest work. Although the frequency of all accidents (including both professional and non-professional) was diminished in view of the amount of removals, the trend differs a great deal for individual countries. Differences in absolute values can be seen between the countries with predominant machine logging and hauling and the countries with predominant Croatian Journal of Forest Engineering 28(2007)1


Fatal accidents in forestry in some European countries (55–62)

long logs technology. With its high number of fatalities, Slovenia lags well behind other countries, and on the basis of these comparisons it can be concluded that in Slovenia we should begin to monitor the actual state of accident safety occurring during non-professional forest work and to establish, on this basis, a strategy to reduce the number of accidents. Apart from recording and analysing the state of affairs especially in the sphere of forest-work training and organisation of special accident and social insurance, the measures to achieve this goal also include encouraging entrepreneurship and integration of privately owned forests within larger complexes. A decrease in the number of work-related accidents and deaths in forests is only possible with an integral approach to suitable training and use of appropriate organisational and technological solutions. The present attitude of the society and the State towards monitoring safety in view of almost 80% of privately owned forests is directly reflected in the trend of accident deaths occurring during work in these forests in comparison with other countries within the Alpine area and Europe in general. The number of fatalities is an important indicator of mastering the risks and shows the effectiveness as well as integrity of measures taken by individual countries in their attempts to provide for safety at forest work. The analysis shows that investments in human resources and humanisation of forest work are critical in Slovenia and several times worse than in other European countries.

J. KLUN and M. MEDVED

Blom, K., 2006: Anmälda arbetsolyckor ar 2005 i Informationssystemet om arbetsskador (ISA) orsakade av: Stormen Gudrun. Source: Microsoft PowerPoint presentation, <http://www.sakerskog.se/images/Gudrun.ppt> (Accessed 1.8. 2006). Eurostat, 2001: European statistics on accidents at work (ESAW) Methodology. Source: <http://ec.europa.eu/employment_social/publications/2002/ke4202569_en.pdf> (Accessed 1.8. 2006). Gfra, 2005: Global forest resources assessment. Source: <http://www.fao.org/forestry/site/fra2005/en/> (Accessed 1.8. 2006). Herbert, R., Landrigan, P. J., 2000: Work-Related Death: A Continuing Epidemic. American Journal of Public Health 90(4): 541–545. ILO, 1981: Occupational Safety and Health Problems in the Timber Industry. Report II, Geneva, Tripartite Technical Meeting for the Timber Industry, International Labour Organization. Leigh, J. P., 1987: Estimates of the probability of job-related death in 347 occupations. Journal of Occupational Medicine 29(6): 510–519. Mcpfe, 2003:. Improved Pan-European indicators for sustainable forest management. Source: <http://www.mcpfe. org/publications/pdf/improved_indicators.pdf> (Accessed 1.8. 2006). Nick, L., 2005: Deutliche Zuwächse im Neumaschinengeschäft bei Vollerntern und Tragschleppern. KWF – Forsttechnische Informationen 57(8–9): 97–98.

5. References – Literatura

Poschen, P., 1993: Forestry, a safe and healthy profession? Source: <http://www.fao.org/docrep/u8520e/u8520e00.htm> (Accessed 1.8. 2006).

National Board of Labour Protection, 1988: Industrial accidents. Helsinki, National Board of Labour Protection.

Pröll, W., 2003: 200 Harvester in Österreich, Arbeit im wald 58(10): p. 24.

Ammann, M. et al., 2002: Arbeitssicherheit bei Holzerntearbeiten – Schlussbericht der Arbeitsgruppe. Bern, UMWELT-MATERIALIEN NR. 150 Wald, Bundesamt für Umwelt, Wald und Landschaft BUWAL, 61 p.

Pröll, W., 2005: Harvester – Einsatz steigt. Österreichische Forstzeitung – Arbeit im Wald 116(12): 4–5.

Axelsson, S.-Å., 1998: The mechanization of logging operations in Sweden and its effect on occupational safety and health. Journal of Forest Engineering 9(2): 25–31.

Strack, J., 2006: Arbeitsunfälle bei Wald-/Forstarbeiten in der Landwirtschaftlichen Unfallversicherung (LUV) – Unfallsituation bei der Waldarbeit in Deutschland. In: Interforst Kongress 2006, München, p. 36.

Sa`etak

Smrtne nesre}e u {umarstvu u nekim europskim zemaljama Razvoj sigurnosti pri radu vidi se posljednjih 25 godina tako|er i u podacima o najozbiljnijim nesre}ama pri {umskom radu. Podaci o smrtnim nesre}ama nisu pritom tek mu~ni brojevi, ve} odra`avaju ulogu izobrazbe, osposobljavanja, za{tite i unapre|enja osobne sigurnosti radnika, za{titne opreme, tehnolo{koga razvoja, organizacije i provo|enja {umskoga rada. Unato~ zna~ajnomu razvoju tehnika i informacijskih tehnologija {umarski se posao jo{ uvijek smatra jednim od najopasnijih zanimanja na svijetu.

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U ~lanku se uspore|uju smrtne nesre}e koje se s obzirom na obujam posje~enoga drva doga|aju pri profesionalnom i neprofesionalnom {umskom radu. [umske radove ne izvode samo osposobljeni profesionalni radnici, ve} i vlasnici {uma, njihovi ro|aci i poznanici koji nisu dovoljno kvalificirani za obavljanje {umskih radova. Pretpostavka je pritom da radove u {umama koje su u vlasni{tvu dr`ave, poduze}a ili velikih posjednika izvode profesionalni {umski radnici, dok radove u malim privatnim {umama naj~e{}e provode nekvalificirani izvoditelji, {to je u ovom radu uzeto za neprofesionalni {umski rad. Cilj je istra`ivanja smrtnih nesre}a pri profesionalnom i neprofesionalnom {umskom radu da se ustanove izvori i vrsno}a podataka te na temelju njih da se utvrde razlike izme|u odabranih zemalja u u~estalosti nesre}a s obzirom na obujam obavljenoga rada. Smatra se da se smrtne nesre}e bilje`e to~nije i pa`ljivije od ostalih ozljeda pri radu. Pritom su podaci o nesre}ama pri profesionalnom {umskom radu potpuniji od onih pri neprofesionalnom {umskom radu. U radu su prema petogodi{njim razdobljima analizirani podaci za razdoblje od 1980. do 2004. godine. Za Sloveniju i Austriju analizirano je svih pet razdoblja, za [vicarsku ~etiri, dok su podaci za Njema~ku, Finsku, [vedsku i Hrvatsku obuhvatili manji broj promatranih razdoblja. U~estalost smrtnih slu~ajeva iskazana je brojem nesre}a na 1 milijun m3 posje~enoga drva. Broj smrtnih nesre}a pri profesionalnom {umskom radu znatno je smanjen u promatranom vremenu gotovo u svim zemljama. U usporedbi s prvim petogodi{njim razdobljem broj nesre}a me|u profesionalnim {umskim radnicima uglavnom je prepolovljen. Posebno su dojmljivi podaci zabilje`eni za [vedsku i Finsku gdje je u zadnjih deset godina broj smrtnih slu~ajeva bio manji od 0,1 nesre}e na 1 miliun m3 posje~enoga drva. U Hrvatskoj je zabilje`en porast broja smrtnih slu~ajeva. U Sloveniji je tako|er zabilje`eno manje smrtnih slu~ajeva u razdoblju 1990–1994. nego nakon 1995. godine. Smrtni slu~ajevi pri neprofesionalnom {umskom radu najbrojniji su u Sloveniji. Osim za Sloveniju podaci za cijelo razdoblje 1980–2004. dostupni su jo{ samo za Austriju u kojoj je broj nesre}a s po~etnih 3 smanjen na 1,5 slu~ajeva na 1 milijun m3 posje~enoga drva. U Sloveniji je broj smrtnih slu~ajeva smanjen sa 8,6 na 7,3. U [vicarskoj je u posljednjih 25 godina u~estalost nesre}a smanjena 2,5 puta. Prili~no su uspje{ne i Njema~ka i [vedska u kojima je broj nesre}a smanjen 1,7 odnosno 3,3 puta. Apsolutno najve}a u~estalost nesre}a (9,52) zabilje`ena je pri neprofesionalnom radu u Sloveniji u razdoblju od 1990. do 1994. godine. Najmanja je u~estalost nesre}a (0,03) utvr|ena pri profesionalnom {umskom radu u [vedskoj (2000–2004) i Finskoj (1995–1999). U posljednjem razdoblju (2000–2004) najvi{e je smrtnih slu~ajeva zabilje`eno pri profesionalnom radu u [vicarskoj (1,00). [to se ti~e trenda smanjenja ukupnoga broja nesre}a, najuspje{nija je [vedska. U [vicarskoj i Austriji njihova je u~estalost prepolovljena, dok u Sloveniji u tom pogledu nije zabilje`en zna~ajniji napredak. Razlike izme|u promatranih zemalja uzrokovane su razli~itim pristupima u pru`anju sigurnosti i za{tite zdravlja, kao i ozbiljnosti obrade statisti~kih podataka o nesre}ama pri {umskom radu. Broj smrtnih nesre}a va`an je pokazatelj razine prevladavanja opasnosti pri {umskom radu, te u~inkovitosti i obuhvatnosti mjera koje pojedine zemlje provode u nastojanjima da osiguraju sigurnost pri {umskom radu. Klju~ne rije~i: {umski rad, smrtne nesre}e, europske zemlje

Authors’ address – Adresa autorâ:

Received (Primljeno): December 20, 2006 Accepted (Prihva}eno): February 12, 2007

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Jaka Klun, BSc. e-mail: jaka.klun@gozdis.si Mirko Medved, PhD. e-mail: mirko.medved@gozdis.si Slovenian Forestry Institute Department of Forest Technique and Economics Ve~na pot 2 1000 Ljubljana SLOVENIA Croatian Journal of Forest Engineering 28(2007)1


Subject review – Pregledni ~lanak

Status and development of forest harvesting mechanisation in Croatian state forestry Darko Beuk, @eljko Toma{i}, Dubravko Horvat Abstract – Nacrtak This paper deals with the present status of forest management in the Republic of Croatia with a special reference to forests managed by the company »Hrvatske {ume« d.o.o. Zagreb, as well as to aims, tasks and methods of state-owned forest management, to conditions and trends in the number of the most significant forest machines used so far in forest harvesting. Also, the ways and activities are described by which »Hrvatske {ume« d.o.o., in cooperation with the Faculty of Forestry, University of Zagreb, influence the trend of machine and technology development, as original solutions for meeting particularly demanding conditions of natural forest management. In the Republic of Croatia, the state owns 75% of the total area of forests and forest land, i.e. 2,018,987 ha are managed by »Hrvatske {ume« d.o.o. »Hrvatske {ume« d.o.o. carry out more than 50% of forest management activities by their own production forces and means. Therefore, the development of machines and technologies is a very significant precondition for improving business efficiency in severe terrain conditions, characterised by specific management methods. Four main criteria of suitability requirements, i.e. suitability of technical-technological solutions, can be singled out: Þ Environmental suitability Þ Efficiency Þ Safety Þ Ergonomic suitability. These criteria have partly been established in line with modern international standards, applicable to conditions in the Republic of Croatia and partly by specific features of management conditions. The influence of »Hrvatske {ume« on meeting the above requirements, and direct participation of »Hrvatske {ume« in the development of technical-technological solutions suitable for certain conditions, have been shown on examples of development of two types of skidders and tractor assemblies for lowland forest thinning. Efforts are made to meet these requirements through tasks of the scientific-research work projects and in cooperation with the Faculty of Forestry, University of Zagreb, as well as by placing demands on and in cooperation with domestic manufacturers of machines and equipment. Keywords: Hrvatske {ume d.o.o., natural forests, development of machines and technologies, skidders, tractor assemblies

1. Introduction – Uvod »Hrvatske {ume« d.o.o. Zagreb is a company in charge of the management of forests and forest lands owned by the Republic of Croatia, in accordance with the Forest Act (Official Gazette 140/2005). Since forests and forest land are exceptionally significant natural resources, they are under special protection of the Croatian state, which chose sustainable development of these resources in accordance with panCroatian Journal of Forest Engineering 28(2007)1

-European measures and recommendations of modern forest science and profession. Nowadays, some especially important pan-European criteria for such a sustainable management refer to the care of forest ecosystems as significant contribution to global carbon cycle, water and soil protection and their favourable influence on current climate conditions, support of biological diversity and landscape specifics, increase of forest ecosystem efficiency related to the production of forest biomass and other generally useful be-

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Thanks to a long-standing forest tradition, in which the relation towards forest management has been based on scientific-professional principles since old times, the natural structure and stability of forests have been almost entirely kept to the present day in

the Republic of Croatia. This tradition is based on organised management of forest stands, which started in Croatia at the same time as in the most developed parts of Europe. Thus, forest offices as terrain organisational units, in which the basic manufacturing-professional activities of forest and forest land management have been carried out, were established for the first time in these areas as early as 1767, i.e. almost 240 years ago. The first three forest offices in the area of today’s Croatia were as follows: forest office of Krasno, O{tarije and Petrova Gora. According to the data of the Forest Management Plan of the Republic of Croatia for the period 2006– 2015, 42% of the state land area in the Republic of Croatia is covered by various forms of forest vegetation (24,028 km2), of which state ownership accounts for 78% and private ownership for 22%. A part of state forests is also used by other legal and economic entities pursuant to regulations on protected parts of forest vegetation (national parks) or certain provisions regulating the purpose of forest use, such as military requirements, scientific research, water-management activities and some other purposes. It can be seen from the share in growing stock that the growing stock in state forests is higher than in private ones, as the result of inadequate management in private forests in the period after the end of the Second World War, primarily due to the system which favoured social ownership, and also due to great fragmentation of private forest property and hence impossibility of application of profitable technologies in their management.

Fig. 1 Forest and forest land ownership structure in the Republic of Croatia by percentage share Slika 1. Vlasni~ka struktura {uma i {umskoga zemlji{ta u Republici Hrvatskoj prema udjelu u povr{ini

Fig. 2 Ownership structure of forests in the Republic of Croatia by share in growing stock Slika 2. Vlasni~ka struktura {uma u Republici Hrvatskoj prema udjelu u drvnoj zalihi

nefits, as well as improvement and protection of other socio-economic functions of forest. Such a demanding forest management, which implies primarily the maintenance of natural features and stability of forests and other ecosystems could not be performed without preservation and support of autochthonous species in regeneration, care and use of forests as means and ways of creating preconditions for ensuring the optimal natural site conditions. A forest management method significantly influences the development of tools for work and applied procedures, while the specific features of work conditions demands complex and special work procedures and technologies. Therefore, the development of forestry machines of the Republic of Croatia was under a strong influence of the management method and working conditions characterised by exceptionally uneven forest stand conditions in the whole area. The same factors are closely related to forest infrastructure, which refers to the forest road network of various degrees of openness, as well as traffic purpose and significance.

2. Forest management in the Republic of Croatia – Gospodarenje {umama u Republici Hrvatskoj

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Status and development of forest harvesting mechanisation in Croatian state forestry (63–82)

Fig. 3 Structure of forests according to their purpose (forests managed by »Hrvatske {ume« d.o.o.) Slika 3. Struktura {uma prema namjeni ({ume kojima gospodare »Hrvatske {ume« d.o.o.) 91% of all forest areas managed by »Hrvatske {ume« d.o.o. refers to commercial forests, 7% are protective forests, while 2% are special purpose forests. Commercial forests, apart from the basic task of protecting and improving their functions of general benefit, are primarily used for timber production. The purpose of protective forests is primarily the protection of land, water, settlements, facilities and other goods, while the special purpose forests are used for controlled production of forest seeds, scientific research, defence requirements of the Republic of Croatia, purposes regulated by special regulations or they belong to protected parts of nature under special legal protection. Most state forest areas (59%) are situated in the so-called continental part of the Republic of Croatia, in the hinterland and primarily comprise even-aged and selective commercial forests, while about 41% of mostly degraded forms of forests are located in the coastal area along the Adriatic sea (littoral karst forests) or belong to a part of the so-called high karst, a bit distant from the coastal area and higher areas of hinterland, leaning on or entering the areas of forests with selective management method. Figure 6 shows that the main species of trees in forests managed by »Hrvatske {ume« d.o.o., as well as in the whole Croatia, are beech trees with the growing stock of 113 mil. m3, pedunculate oak with 45 mil. m3, and sessile oak with 29 mil. m3, together making 61% of the total growing stock. The most valuable species of trees in the forests of the Republic Croatian Journal of Forest Engineering 28(2007)1

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Fig. 4 Structure of forests by geographical position (forests managed by »Hrvatske {ume« d.o.o.) Slika 4. Struktura {uma prema zemljopisnomu polo`aju ({ume kojima gospodare »Hrvatske {ume« d.o.o.)

Fig. 5 Silvicultural forms of forests (covered areas managed by »Hrvatske {ume« d.o.o.) Slika 5. Uzgojni oblici {uma (obrasle povr{ine kojima gospodare »Hrvatske {ume« d.o.o.) of Croatia is pedunculate oak (Quercus robur L.) of a well known quality and very demanding management conditions. It can be seen from the relation between the annual increment of the growing stock and annual allowable cut regarding tree species (Fig. 7 and 8) that this relation is mostly observed by the three main commercial tree species: pedunculate oak, ses-

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Fig. 6 Growing stock by tree species (forests managed by »Hrvatske {ume« d.o.o.) Slika 6. Drvna zaliha prema vrstama drve}a ({ume kojima gospodare »Hrvatske {ume« d.o.o.)

Fig. 8 Annual allowable cut by tree species (forests managed by »Hrvatske {ume« d.o.o.) Slika 8. Godi{nji etat po vrstama drve}a ({ume kojima gospodare »Hrvatske {ume« d.o.o.)

Fig. 7 Annual increment of the growing stock by tree species (forests managed by »Hrvatske {ume« d.o.o.) Slika 7. Godi{nji prirast drvne zalihe po vrstama drve}a ({ume kojima gospodare »Hrvatske {ume« d.o.o.)

Fig. 9 Growing stock and allowable cut in even-aged and selective forests (forests managed by »Hrvatske {ume« d.o.o. for the period 2006–2015) Slika 9. Drvna zaliha i etat u jednodobnim i prebornim {umama ({ume kojima gospodare »Hrvatske {ume« d.o.o. za razdoblje 2006 – 2015)

sile oak and beech, whereby the annual allowable cut accounts for approximately 73% of annual increment (Fig. 10). As far as the management method is concerned, Figure 9 shows that the annual allowable cut in even-aged forests with respect to the growing stock of these forests is higher by 0.3% than the annual allowable cut with respect to the growing stock of selective forests. Figure 10 shows total growing stock, annual increment and annual allowable cut in forests of the

Republic of Croatia, established by the new Forest Regional Economic Policy of the Republic of Croatia for the period 2006–2015. According to these data, it can be seen that the unit increment is much higher in private forests than in state ones, which is the result of the above mentioned unfavourable relations towards this ownership category in the period after the Second World War in these areas, as well as of fragmentation of such forest property. As far as the growing stock increment is concerned, similar rela-

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Fig. 10 Growing stock, annual increment and allowable cut of the Croatian forests in the period 2006–2015 Slika 10. Drvna zaliha, godi{nji prirast i etat {uma Republike Hrvatske za razdoblje 2006 – 2015. tions were observed regarding the volume of annual allowable cuts in private forestry. The new Forestry Act of the Republic of Croatia has created conditions for renewal of and higher investments into private forests with the aim of improving their structure and overall management.

3. Status and possibilities of development of machinery and technology in the management of state forests of the Republic of Croatia – Stanje i mogu}nosti razvoja mehaniziranih sredstava za rad i tehnologija u gospodarenju dr`avnim {umama Republike Hrvatske The very beginning of work mechanisation in the forests of the Republic of Croatia can be identified with the beginning of use of farm tractors in the second half of the last century as a means of transCroatian Journal of Forest Engineering 28(2007)1

port and timber skidding and somewhat later (in the 60s) in establishing plantations of the Euro-American poplars. Since then many works, originally only performed manually, moved from the zerostate into the first degree of mechanisation by transformation into manual-machine works, like tree felling and processing (Sever 1993). Timber was mostly skidded by animals, and tractors were introduced into timber harvesting in order to ease hard work to people and animals. Although the beginning of use of farm tractors, together with the introduction of chainsaw for tree felling and processing, was in a way a turning point in the mechanisation of works in forest management in the Republic of Croatia, it cannot be considered the beginning of development of certain technologies of timber harvesting or silvicultural operations characteristic of specific work conditions, since these machines had many faults caused by their originally inadequate purpose (Horvat and Toma{i} 1993). In early 1960s there were already more than 200 farm tractors working in the

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Fig. 11 Trends in the number of adapted farm tractors in state forestry of the Republic of Croatia in the period 1961–2006 Slika 11. Kretanje broja nadogra|enih poljoprivrednih traktora u dr`avnom {umarstvu Republike Hrvatske u razdoblju 1961 – 2006.

Fig. 12 Trend in the number of skidders in state forestry of the Republic of Croatia in the period 1969–2006 Slika 12. Kretanje broja skidera u dr`avnom {umarstvu Republike Hrvatske u razdoblju 1969 – 2006. Croatian forestry (Fig. 12). This figure shows that the number of farm tractors reaches the highest values in two periods: in mid-1960s and 1980s, while in late 1990s it significantly decreases, levelling off at the reached number of about 300, when a significant part of farm tractors was only used for silvicultural operations. The moment of introduction of the first specialised machines, skidders and forwarders, in the Croa-

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tian forestry in 1970s can be considered the beginning of designing and development of today’s procedures in forest silviculture and forest harvesting, which primarily depend on natural characteristics of the forest area and silvicultural method (Be|ula and Slabak 1974). Figures 12 and 13 show the trend in the number of skidders, i.e. forwarders in the forestry of the Republic of Croatia. It can be noted that the period of intensive mechanisation with these machiCroatian Journal of Forest Engineering 28(2007)1


Status and development of forest harvesting mechanisation in Croatian state forestry (63–82)

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Fig. 13 Trends in the number of forwarders in state forestry of the Republic of Croatia in the period 1971–2006 Slika 13. Kretanje broja forvardera u dr`avnom {umarstvu Republike Hrvatske u razdoblju 1971 – 2006. nes started in early 1970s and lasted almost till late 1980s, when the achieved number started stagnating, with a mild increase in the last several years. The appearance of these specialised machines and technologies in the Croatian forestry does not lag significantly behind the trends in Europe and in the whole world. More favourable features of these machines, whose exclusive purpose was timber skidding, provided by manufactures’ design solutions, enabled the determination of procedures in performing individual (semi)phases of forest harvesting: felling, processing, skidding and transportation of wood due to close connection between procedures and choice or use of a specific technique. In that way, the basic methods of forest harvesting were gradually developed in the forestry of the Republic of Croatia, and they were adapted to terrain and stand conditions (Krpan et al. 2003): Þ In regenerative felling of lowland forests, where the most valuable species is the pedunculate oak, a cut-to-length method is used in felling and processing, and forwarders are almost exclusively used for the removal of processed timber to the landing, wherever the soil is of sufficient bearing capacity. Timber is removed by forwarders on wheels since in that way much less damage is caused to seedlings than in ground skidding. In thinnings of these forests where a cut-to-length method of felling and processing is also used, timber is also Croatian Journal of Forest Engineering 28(2007)1

removed on wheels from the forest to the landing. However this operation is carried out by smaller machines, the so-called tractor assemblies, which consist of an adapted farm tractor, semi-trailer and loader which can also be equipped with a winch. Þ On sloping terrains in hilly areas, timber skidding is mostly performed by skidders in regenerative felling of even-aged forests and selective felling with the use of a half-length method of felling and processing, while in thinnings of even-aged forests of these areas, with the use of cut-to-length method of felling and processing, apart from middle thinning skidders, adapted farm tractors with winch are also used.

3.1 Felling and processing – Sje~a i izradba drva In Croatian forestry manual-machine work is used for felling and processing. Felling is carried out by chain saws. Chain saws are also used for delimbing, bucking and cutting. Machines for tree felling and processing are not used in Croatia. Their use in our country is mostly limited by natural origin of forests, wood species and tree dimensions, macrorelief and microrelief, methods of forest silviculture and management and others (Krpan 2000). The interest of the forestry profession in Croatia for a completely mechanised system of short wood skidding, which ensures a technological and manufacturing step forward from the usual procedures of forest harvesting,

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Fig. 14 Thinning of hard broadleaved trees by harvester Slika 14. Proreda tvrdih lista~a harvesterom can be seen in two pilot trials of machine felling and processing carried out by a one-grip harvester with timber extracted by a forwarder. The pilot works were carried out in June 2001 by sanitary felling of pine culture (Krpan and Por{insky 2001, Krpan and Por{insky 2002a) and in September 2002 by clear cut of fast growing deciduous species, i.e. thinning of natural stands of hard broadleaved trees (Krpan and Por{insky 2002b). Despite the acquired experience and favourable research results (Krpan and Por{insky 2004a, Krpan and Por{insky 2004b, Krpan et al. 2004, Por{insky et al. 2004), the introduction of a harvester-forwarder system, which represents today’s top technology of forest harvesting, remained in Croatia at the level of experiments. It should be pointed out, however, that the present organisation of »Hrvatske {ume« d.o.o. enables the use of a certain number of such high technology machines in Croatian forestry. Most of felling and processing in »Hrvatske {ume« d.o.o. is carried out by their own workers, about one fifth is carried out by contractors and a part is carried out by local inhabitants. The latter mostly refers to forest wood residues and wood from the so-called cleaning of stands, which has no technical value and it is usually self-processed for energy needs (Fig. 15).

3.2 Timber extraction – Privla~enje drva Timber is extracted in two significantly different ways: ground skidding and timber forwarding, with

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Fig. 15 Wood felling and processing by service providers in 2006 (forests managed by »Hrvatske {ume« d.o.o.) Slika 15. Sje~a i i izradba drva prema izvr{iteljima u 2006. godini ({ume kojima gospodare »Hrvatske {ume« d.o.o.) which the method of felling and processing is closely connected. According to the above basic methods of extraction, which depend on stand and terrain conditions and partly on the so-called technical heritage, about more than half of the allowable cut in the Croatian state forests is skidded/forwarded by the machinery of the company »Hrvatske {ume« d.o.o. and the rest is by third-party contractors (Fig. 16). Croatian Journal of Forest Engineering 28(2007)1


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Despite numerous disadvantages and low production level, a considerably large number of farm tractors adapted for forest work have still been retained by the company »Hrvatske {ume« d.o.o., primarily due to quite a large quantity of industrial timber and wood for chemical processing obtained after thinning (thinning accounts for 35% of the total allowable cut). More than a fifth of the total quantity of timber extracted by »own forces« is carried out with these machines (Fig. 17 and 18, Table 1). These figures show that almost three fifths of the total quantity of processed timber is skidded by skidders and less than a fifth is forwarded by forwarders. Figures 17 and 18 show a great difference in productivity between adapted farm tractors and skidders: almost three fifths of processed timber is skidded by 270 skidders, while at the same time only somewhat more than one fifth is extracted by 280 adapted farm tractors. It should be noted, however, that most of the time approximately one third of farm tractors are also engaged in forest silvicultural works.

Fig. 16 Wood skidding/forwarding by service providers in 2006 (forests managed by »Hrvatske {ume« d.o.o.) Slika 16. Privla~enje drva prema izvr{iteljima u 2006. godini ({ume kojima gospodare »Hrvatske {ume« d.o.o.)

Type of vehicle Vrsta vozila

Average number of vehicles, pcs. Prosje~an broj vozila, kom.

Average annual productivity, m3 Prosje~an godi{nji u~inak, m3

Average annual productivity of vehicle, m3/year Prosje~an godi{nji u~inak po vozilu, m3/god.

Average daily output of vehicle, m3/day Prosje~an dnevni u~inak po vozilu, m3/dan

Average annual operating hours, h/year Prosje~no godi{nje ostvareni radni sati po vozilu, h/god.

Average annual days per vehicle, day/year Prosje~no godi{nje ostvareni radni dani po sredstvu, dan/god.

Utilisation, % Iskori{tenost, %

Availability, % Ispravnost, %

Table 1 The average efficiency of wood skidding/forwarding for the period 2002–20061 Tablica 1. Prosje~no ostvarenje privla~enja drva za razdoblje 2002–2006.1

Farm tractors >1,5 t Farm tractori >1,5 t

282

376 345

1333

9

1131

141

56

80

Skidders <5t Skideri <5t

103

231 471

2238

14

1317

165

65

83

Skidders >5t Skideri >5t

168

782 438

4666

27

1391

174

68

86

Forwarders Forvarderi

25

327 936

13117

70

1506

188

62

80

579

1 718 190

2970

19

1256

157

61

82

Total Ukupno

1

Data from the software used by »Hrvatske {ume« d.o.o. – Monitoring of expenses and efficiencies of production machines, which represents a monthly report of machine work. Data are entered at the level of forest offices, work units and forest administrations, individually for each machine and are summed up at the level of the company »Hrvatske {ume« d.o.o. where they are processed into a final report. – Podaci iz programske aplikacije »Hrvatskih {uma« d.o.o. – Pra}enje tro{kova i u~inaka strojeva u proizvodnji koja predstavlja mjese~no izvje{tavanje o radu strojeva. Podaci se unose na razini {umarija, radnih jedinica i u uprava {uma podru`nica, pojedina~no za svako sredstvo te se zbrajaju za razinu trgova~kog dru{tva »Hrvatske {ume« d.o.o. gdje se obra|uju kroz `eljeni izlazni izvje{tajni oblik.

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and only one fifth is transported by trucks owned by »Hrvatske {ume« d.o.o. This is partly the result of wood selling policy, which enables buyers to transport wood by their own trucks, but also the result of the general situation in the market of these services. The part of wood transport carried out by the capacities of »Hrvatske {ume« d.o.o. consists of up-to-date means of transport and loading machines which do not lag behind the European or world trends and technologies (Toma{i} et al. 2005).

Fig. 17 Average shares and quantities of wood extracted by the machinery of »Hrvatske {ume« d.o.o. in the period 2002–2006 by vehicle type Slika 17. Prosje~ni udjeli i koli~ine privu~enoga drva vlastitim sredstvima »Hrvatskih {uma« d.o.o. u razdoblju 2002 – 2006. prema vrsti vozila

Fig. 19 Wood transportation by service providers in 2006 (forests managed by »Hrvatske {ume« d.o.o.) Slika 19. Prijevoz drva prema izvr{iteljima u 2006. godini ({ume kojima gospodare »Hrvatske {ume« d.o.o.)

Fig. 18 Average annual productivity of vehicles for timber extraction (»Hrvatske {ume« d.o.o., period 2002–2006) Slika 18. Prosje~na ostvarena godi{nja proizvodnost sredstava za privla~enje drva (»Hrvatske {ume« d.o.o., razdoblje 2002 – 2006)

The productivity of forwarders is several times higher than the productivity of all machinery used for timber skidding (Fig. 18).

3.3 Wood transportation – Prijevoz drva It can be seen from Figure 19 that almost four fifths of wood felled in the state forests of the Republic of Croatia are transported by private contractors

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Fig. 20 Building of forest roads by service providers in 2006 (forests managed by »Hrvatske {ume« d.o.o.) Slika 20. Izgradnja {umskih prometnica prema izvr{iteljima u 2006. godini ({ume kojima gospodare »Hrvatske {ume« d.o.o.) Croatian Journal of Forest Engineering 28(2007)1


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3.4 Building of forest roads – Izgradnja {umskih prometnica In 2005 the total length of forest roads in forests managed by »Hrvatske {ume« d.o.o. was 15.5 thousand km, which ensured total openness of about 7.8 m/ha. Figure 20 shows that in 2006 about 55% of the value of all jobs related to designing and building of forest roads was performed by capacities of »Hrvatske {ume« d.o.o., while 45% of these services were provided by contractors.

4. The influence of »Hrvatske {ume« d.o.o. on the development of mechanisation of procedures and technologies, and harmonisation of development trends with management purposes – Utjecaj »Hrvatskih {uma« d.o.o. na razvoj mehaniziranosti tehnologija i tehni~kih sredstava i usmjeravanje razvojnih tokova u skladu s ciljevima gospodarenja »Hrvatske {ume« d.o.o. influence the formation and development of procedures and technologies in state forest management, which can be seen in several basic requirements: Þ Environmental suitability of applied procedures and technologies Þ Efficiency in compliance with working conditions Þ Meeting safety requirements of use of machines and technologies Þ Ergonomic suitability of machines. Within the scientific-research programme financed by »Hrvatske {ume« d.o.o., the very choice of the research subject speaks for itself about the significant interest in projects which include research topics related to the above requirements. Proposals for research topics have mostly come as a result of practice, but they have also been defined by development and production services of the Company, and namely: Þ Technologies of ground wood skidding Þ Ecologically acceptable technologies in forest management according to applicable international standards Þ Machine methods of slash stacking after felling and processing Þ Ecologically acceptable forest techniques Þ Licensing and accreditation for achieving European standards of safety and quality of forest work Þ Ergonomic characteristics of forest machines and establishment of conditions of these machines. Croatian Journal of Forest Engineering 28(2007)1

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4.1 Focus on development of environmentally acceptable forest machines and technologies – Nagla{ena okrenutost razvoju okoli{no prihvatljivih {umarskih strojeva i tehnologija The awareness of the comprehensive meaning of development, introduction, implementation and upgrading of such procedures and technologies, based on ecological acceptability, prevails as one of the basic aims of the profession upon which most of other aims depend and without which they could never be achieved. Therefore, much attention was focused on preventing adverse effects and/or decrease of adverse effects caused by the implementation of certain procedures and use of certain machines in forest management. Environmentally harmful effects caused by work of forest machinery can be mechanical and chemical. The research of environmental suitability of implemented methods and technologies, focused on mechanical damage to forest soil, involve the determination of soil compaction by wheels and skidded load performed by measuring changes of physicalmechanical soil characteristics (penetrating and shear resistance, changes of moisture content and pore volumes, determining wheel numeric, etc.). Mechanical and chemical damaging influence of machine work can cause significant damage to standing trees and other plants, as well as to animal world and its habitats. Therefore, such a damaging effect is also investigated. Attention is focused on studying harmful chemical changes in soil, also related to machine operations, by which biological soil function is jeopardised, as depository of food for the existing and future forest vegetation and irreplaceable storage and source of drinking water. Emission of hazardous gases, condensates and liquified harmful substances into environment and atmosphere should also be mentioned as harmful chemical effects of machine operations. One of such researches refers to comparative research of the biological-chemical influence of mineral and biodegradable lubricants spilled on the ground by use of chain saws and skidders/forwarders. It particularly refers to systematic spillage of large quantities of oil for lubricating saw chains into forest soil, as all felling and processing of the allowable cut is carried out by chainsaws. It is known from previous research that the unit consumption of oil for lubricating chain saws is between 0.11 and 0.15 L/m3. Taking into account the lowest unit consumption, according to the average net annual allowable cut in »Hrvatske {ume«, the result is that more than half a million litre of oil only used for lubricating of saw

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Fig. 21 Research of the effects of biodegradable and mineral lubricants in soil Slika 21. Istra`ivanje posljedica djelovanja u tlu odlaganih biolo{ki razgradivih i mineralnih maziva chains is deposited into forest soil per year. Although a small quantity of lubricants remains in the processed wood and one part on the surrounding plants, still almost half a million litre of oil is spilled into the soil. If quantities are added of hydraulic oil spilled from hydraulic systems and systems of other machines (faults, carelessness), which cannot possibly be estimated, then it becomes clear what quantities are dealt with here. The fact should be kept in mind that by entering into soil mineral lubricants (which have a very poor degradability) jeopardise underground waters to such an extent that one litre of that lubricant can pollute thousand litres of underground water, but also make worthless about 1 million litre (Augu{tin et al. 2000). The research of the effects of biodegradable and mineral oils is carried out so that a certain area of forest soil covered with e.g. oak pedunculate acorn is watered by various concentrations of biodegradable or mineral lubricants mixed with water, and effects and results are recorded of the influence of such watering by the solution of both types of lubricants on planted seeds and young plants (germination, growth and increment of seedlings, etc). These researches are still under way and the results have not yet been determined (Fig. 21). Apart from the research of the influence of lubricants on forest soil and its biological productivity, increasing interest has been recorded for the biological propulsive fuel used by forestry machines in the Republic of Croatia. Thus, in 2005 the first Croatian thinning skidder driven by bio-diesel was manufactured in Rijeka and all hydraulic oils are biodegradable (Sever and Puljak 2005).

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4.2 Participation in the development of machines and technologies – Sudjelovanje u razvoju strojeva i tehnologija 4.2.1 Participation of »Hrvatske {ume« d.o.o. and the Faculty of Forestry, University of Zagreb in the development of special forest machines – Sudjelovanje »Hrvatskih {uma« d.o.o. i [umarskoga fakulteta Sveu~ili{ta u Zagrebu u razvoju posebnih {umarskih strojeva »Hrvatske {ume« d.o.o. and forestry science (Faculty of Forestry, University of Zagreb) have a great influence on the development of mechanised vehicles as a result of the established cooperation with the Croatian manufacturers of forest machines, on which demands are imposed for fulfilling specific technical, safety, ergonomic and other conditions in designing machines. The way in which domestic middle thinning skidders – Ecotrac 55V and skidder Ecotrac 120V were developed is a good example of the participation of the employees of »Hrvatske {ume« d.o.o. in the development of special forest machines. The first machine was intended for work in thinning on sloping terrains and first of all it had to meet morphological demands (width and length) in order to be able to move among standing trees in thinning stands and on the existing and considerably narrow strip roads. Further development of that machine included all demanding ergonomic and safety conditions. Skidder Ecotrac 120V was developed completely in accordance with the demands of the employees of »Hrvatske {ume« and in cooperation with the representatives of forest science with the financial support of the Ministry of Science of the Republic of Croatian Journal of Forest Engineering 28(2007)1


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Croatia (Horvat 2004). Before the beginning of the realisation of this developmental project, a comprehensive survey was carried out of the opinion of operators of similar machines already engaged in timber skidding under given conditions, mechanics experienced in maintenance of similar machines and foremen about the observed disadvantages and advantages of machines, which had been performing similar jobs under similar terrain and working conditions. After having collected their comments, suggestions and opinions, the answers were classified and the review of advantages and disadvantages of the existing machines was made, based on which technical-technological demands were imposed on the manufacturer. They can be reduced to four basic demands, already mentioned above: environmental suitability, productivity, safety and ergonomic features. The first demand of technical suitability in terms of environmental protection is primarily related to the width of strip roads which is between 2.5 and 3 m in forests managed by »Hrvatske {ume« d.o.o. (Pi~man and Pentek 2003). Also attention had to be paid to the machine height and length (axle base) due to low branches and limiting vertical and horizontal curves of the existing strip roads. Since at the same time there were many comments claiming that the mass of some of the existing skidders (9–10 t) was too high in relation to the soil bearing capacity of these areas, the mass of the future skidder was not to exceed 7 t. This is why this skidder was also called »skidder of about 7 t mass« in the period before a prototype was made. Based on morphological analysis (dependence of width, height and length on mass) of families of skidders and middle skidders, the positions of skidders developed in Croatia: a thinning skidder Ecotrac 55V and skidder Ecotrac 120V are shown in Figures 22, 23 and 24. It can be seen from the figures that all demands related to the dependence between skidder size and mass are met and can be considered favourable. There is a particularly favourable relation between the skidders width and mass (Fig. 22), where widths are noticeably below equalisation curves, which is the result of the above mentioned harmonisation between demands of forestry profession and design solutions. These figures also show that the skidder length and height are above the equalisation curve. According to the ISO standard definition, larger length than the average value of other skidders is caused by the installation of the front thrust blade operated by two long stroke hydraulic cylinders, by which quite a big movement curve is enabled, as well as by the rear anchoring blade. The above average skidder Croatian Journal of Forest Engineering 28(2007)1

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height in relation to mass (position of the point above the equalisation curve) also arises out of the definition of the same standard according to which the total height is defined as the distance from the ground to the highest skidder’s point. With these skidders it refers to the edge of the exhaust pipe placed above the cabin roof in order to meet safety demands of ISO standard to prevent the entrance of exhaust gases into the skidder cabin through a ventilation

Fig. 22 Relation between skidder mass and width Slika 22. Odnos mase i {irine skidera

Fig. 23 Relation between skidder mass and height Slika 23. Odnos mase i visine skidera 75


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Fig. 24 Relation between skidder mass and length Slika 24. Odnos mase i duljine skidera opening. Therefore, the total height of the domestic skidder is higher than average values of other skidders listed in database, out of which a large number had been manufactured before the above ISO standards had been issued. The above mentioned database, which was used for the morphological analysis, refers to the database compiled by Sever and Horvat (1985, 1992a, 1992b), Horvat (1996c, 1996d), and later supplemented by data from databases for some features of forest ma-

chines of the Department of Forest Techniques of the Forestry Research Institute of the Austrian Ministry of Agriculture and Forestry (FBVA 2000, FBVA 2003). This database contains a total of 91 types of skidders. The position of the form index of domestic skidders (B/L), which, according to Bekker (1956) defines the penetrability of a vehicle in relation to other machines within the skidder family, is also outside the set demands of the forest practice. As already explained above, the immediate aim for meeting these demands of small machine width was the result of exceptionally narrow strip roads, in most cases not exceeding 2.5 m, and of the use of smaller skidders in thinning operations. Hence, the relations between the width and length are on the very edge of the skidder family and these machines are characterised by a particularly suitable small width in relation to length (Fig. 25). A domestic skidder Silva S101, ten of which were produced in the 1980s in the then Forest Administration of Vrbovsko, was used as an example of a part of technical and dimensional features of skidders. It primarily refers to dimensioning of axles which, after more than two decades of use, proved to be very favourable. Even today four of these machines are used for timber skidding in selective forest conditions. The demand for ensuring productivity was expressed in requiring increased engine power in relation to the average power of the skidder group, by which higher skidding speeds were ensured in hilly and particularly in mountainous stands. The third out of four key demands imposed on the manufacturer of the domestic skidder by the

Fig. 25 Skidder form index Slika 25. Indeksi oblika skidera 76

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science and profession, which according to its significance could have been placed first, referred to the safety of the working machine. Among thirty demands specified by ISO Standard (Horvat and [u{njar 2003), which refer to safety issues and some ergonomic features, the following represent the most important research areas of safety-ergonomic features: Þ Technical safety devices Þ Accessing devices Þ Cabin design (cabin protection, cabin space, seat, zone of comfort and access to control commands) Þ Light devices Þ Steering (proper function of the steering system, control commands forces, symbols of control commands) Þ Safety demands for winch design and operation. The most demanding conditions for confirming the machine safety refer to the skidder cabin. Apart from some other ISO standard demands, it refers particularly to the existence of ROPS (Roll-Over Protective Structure), FOPS (Falling Object Protective Structure) and OPS (Operative Protective Structure). All the demanded conditions were met, including the most demanding cabin tests, which were performed abroad. The most important ergonomic demands for skidders definitely refer to the decrease of harmful effects of noise and vibrations. Some researches of the Institute for Health Protection of the Republic of Croatia showed that noise and vibration have been

Fig. 26 Distribution of causes of professional diseases Slika 26. Razdioba uzroka profesionalnih bolesti Croatian Journal of Forest Engineering 28(2007)1

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the most significant causes of professional diseases in relation to other conditions (Fig. 26) and forestry is ranked second in the number of disabled persons as a result of professional diseases (Horvat and Sever 1997). Measurement of noise level in the skidder cabin, with the so-called silent cabin and modern engine installed, showed that skidders meet all safety-atwork requirements in accordance with the prescribed limit values for noise over an eight hour exposure. Such a level of noise enables free communication at the workplace, provides conditions for reducing injuries at work and for improving total satisfaction of drivers and increasing productivity. All other measuring points showed that the noise level emitted by a skidder was not above the limit values. The noise was measured (Horvat et al. 2004a, Horvat et al. 2004b): Þ in a skidder cabin next to the driver’s ear in accordance with ISO 5131:1996 and ISO 6394: 1998 Þ in the vicinity of the skidder in accordance with ISO 4872: 1978 and ISO 6393:1998 Þ in the vicinity of the skidder during acceleration in accordance with ISO 362: 1998 Þ and it met all requirements prescribed by these standards. Vibrations were measured at two measuring points crucial for determining vibrations risks: on the steering wheel and on the seat. For measuring vibrations on the steering wheel, standards were used for vibrations transferred via fist or from the seat to the whole body and namely HRN ISO 5349: 2001 EN and HRN ISO 5349: 2001 EN. The results showed that vibrations on the steering wheel were well damped with the exception of vibrations at idling. In other words, it means that signs of permanent consequences could only appear with 10% of drivers exposed to measured vibration levels for a comparatively long time, assuming that during a full-time working day engine is kept at the lowest number of revolutions. The conclusion on vibrations transferred from the wheel to hands shows that the examined skidders are ergonomically fit means of work. Vibrations were measured on the seat in accordance with the standard HRN ISO 2361-1: 1997 EN. The measurement results showed that vibrations transferred from the seat to the driver’s body are not a limiting factor. Damping features of seats were well chosen. The driver can spend more than eight hours, the duration of a shift, without any consequences under established conditions.

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4.2.2 Participation of »Hrvatske {ume« d.o.o. and Faculty of Forestry, University of Zagreb in the development of forestry technologies – Sudjelovanje »Hrvatskih {uma« d.o.o. i [umarskoga fakulteta Sveu~ili{ta u Zagrebu u razvoju {umarskih tehnologija The following example refers to the direct participation of »Hrvatske {ume« d.o.o. and forestry science in planning, development and upgrading of original technologies related to conditions in the Croatian forestry. Determination and selection of suitable procedures for thinning operations are among the most significant management issues in naturally regenerated forests of pedunculate oak in the eastern parts of Croatia. According to the tree value (pedunculate oak), these forests are considered the most valuable forests in the Republic of Croatia. However, since these lowland forest stands of oak and ash trees developed on deep pseudogleic soil of a very low bearing capacity and high water content in the soil, there are numerous difficulties related to forest harvesting. They primarily refer to further mechanisation of these works and choice of the most favourable method for extracting timber from the stand after felling. Apart from the above problems related to poor bearing capacity of the soil, the same difficulty is encountered in biological features of the main tree species and the most important commercial species – pedunculate oak, which is also the most sensitive species in the early age of seedlings and offspring. The natural regeneration of pedunculate oak forests is a very complex and expensive procedure, even in case when it is performed properly, professionally and without any mistakes, and it requires a long-term investment and great efforts. Further to the above, in thinnings of these stands it is very important to preserve a sensitive forest soil that has to perform its feeding, productive and supporting task for a long time. Since it is known from many scientific researches, as well as from experience, that much less damage to the soil is caused if timber is forwarded from the forest after felling than when it is skidded, forwarding was promptly chosen. However, this procedure was not considered final, and efforts are being made to find a procedure that would prevent threading of the whole felling site while bunching timber from one stump to another, and provide the possibility of bunching timber exclusively by use of skid trails, without entering into the stand. In this way protection would not only be provided to forest soil but also to standing trees and seedlings in a forest stand. In order to remove cut timber by access tracks, parallel unstocked strips were first made within forest stands at the distance of 75 m, the so-called »strip paths« 3 m wide and

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lately (in newly regenerated stands) these distances were halved and now such paths are made for the same purpose at every 36 m. Their basic role is to ensure free travel of machines and space from which wood is winched and/or loader bunched and then transported to the (roadside) landing. The next thing that has to be taken into account when choosing the right machine, as an important component of the chosen procedure for these conditions, is the fact that timber assortments from thinning are of smaller dimensions and lower quality and make about 35% of the total annual allowable cut. Therefore, the problem of wood removal from the lowland forest thinnings are not only of ecological, but also of economic nature, since the use of considerably expensive machines for this purpose would create working costs that can hardly be covered by wood itself. The extraction of timber after thinning in these areas started in early 1970s by use of first tractor assemblies, which consisted of a farm tractor, forest semitrailer, mechanised console loader and forest winch. The first such tractor assembly was called »Pionir«. Unlike the above mentioned efforts to avoid the entrance of tractors into the stand for timber extraction, »Pionir« assemblies travel across the stand bunching the processed timber and in doing so mostly cause damage to forest soil, seedlings and remaining trees. By making additional parallel strip paths at distances half less than the existing ones (36 m), and thus increasing the forest openness, further progress was made in the described methods of timber extraction in lowland thinnings. In the next period, development and improvement of equipping tractor assemblies continued by more up-to-date hydraulic loaders and forest winches. The activities related to looking for the most favourable solution of the tractor assembly were particularly increased in early 1990s. The next solution included the parallel work of the tractor assembly and adapted farm tractor equipped by a loader and grapple which collected processed timber assortments in the stand and skidded them to the strip path. From the point of view of ecological acceptability and particularly economic feasibility (two machines for the same work and much time spent in loading and unloading, unsuitable mechanised loader), the work organised in this way could not last long (Horvat et al. 2004). In the chronological order the following types of machines, i.e. tractor assemblies were used in these areas for timber extracting: Þ »Pionir« assembly (Fig. 27A): farm tractor, forest semi-trailer, mechanised console loader with winch (in early 1970s) Croatian Journal of Forest Engineering 28(2007)1


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Fig. 27 Various approaches to solving timber skidding from the lowland forest thinning Slika 27. Razli~iti pristupi rje{avanju privla~enja drva iz proreda nizinskih {uma Croatian Journal of Forest Engineering 28(2007)1

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Þ FMV assembly (Fig. 27B): farm tractor Torpedo 55A, semi-trailer Moheda 6 t with a hydraulic loader FMV 230 and hydraulic winch on the loader (1993) Þ thinning skidder with a semi-trailer and hydraulic loader without winch (Fig. 27C), (1996) Þ adapted farm tractor with a loader and grapple (Fig. 27D), in combination with the tractor assembly Þ »Steyr« assembly (Fig. 27E): farm tractor Steyr 860, semi-trailer Kronos 6 t and hydraulic loader Kronos 250 with a hydraulic winch on the loader (1997) Þ »Formet« assembly (Fig. 27F): tractor Steyr 8090 (or any other farm tractor of such power and other appropriate features), a double drum winch Igland 6002 Pronto TL of the rated tractive force of 60 kN, hydraulic loader Igland 43–65 and semi-trailer Metalac S-6, of the carrying capacity of 6 t (2004). It should be mentioned that the work in finding the most favourable approach to timber skidding after thinning is not even close to its completion. The basic problem is to balance several features of the most favourable technological-technical solution, which would meet the requirements of environmental acceptability, safety-ergonomic features and economic feasibility supported by satisfying productivity. Although this sounds utopian, a lot can be achieved in this area by a persistent systematic work on improving each of the above factors individually and with the help of knowledge and science in general.

5. Conclusions – Zaklju~ci Since more than 96% of the total area covered by forests and managed by Hrvatske {ume d.o.o. is of natural structure, specific management of these forests demands original solutions and methods which have to meet set criteria for: Þ environmental suitability Þ efficiency Þ safety Þ ergonomic features. Here, special emphasis is placed on the requirements of ecologically acceptable machines and procedures in forest management, as well as on the possibility of decreasing their unfavourable mechanical and chemical influence on soil and conditions within forest ecosystems in general. »Hrvatske {ume« d.o.o. carry out more than 50% of activities related to forest management by their

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own production capacities, except wood transportation. Therefore, the fulfilment of the above requirements is the objective of scientific-research projects financed by »Hrvatrske {ume« d.o.o., whose experts take active part in the development of the most frequently used machines and methods of timber skidding, like thinning skidder, skidder and technical-technological solutions for lowland forest thinning. While it can be generally said that skidders meet the required conditions, the most favourable variant is still sought for the technical solution of thinning machines in the lowland forests of the Republic of Croatia, since previous solutions failed to meet all the required criteria, particularly not the part related to productivity, as wood from these fellings is of lower technical and economic value.

6. References – Literatura Anon., 2006: [umskogospodarska osnova podru~ja Republike Hrvatske, razdoblje 2006 – 2015. godina. Anon., 2006: Zakon o {umama. Narodne novine, Slu`beni list Republike Hrvatske, br. 140 od 28. 11. 2005, Augu{tin, H., Dekani}, S., Martini}, I., Sever, S., 2000: Okoli{no ne{kodljive hidrauli~ne teku}ine za {umarske strojeve – stanje i izglednost, Mehanizacija {umarstva 25(1–2): 41–58. Bed`ula, D., Slabak, M., 1974: Razvoj mehanizacije {umskih radova na podru~ju isto~ne Slavonije – stanje danas i perspektive (The use of forest machinery in southeastern Slavonia), Zbornik o stotoj obljetnici znanstvenog i organiziranog pristupa {umarstvu jugoisto~ne Slavonije, JAZU, Centar za znanstveni rad Vinkovci, Vinkovci – Slavonski Brod, 1974., str. 185–202. Bekker, M., G., 1956: Theory of land locomotion, The University of Michigan Press, str. 1–499. Horvat D., 1996A: Prora~un nekih veli~ina vu~nih zna~ajki ~etiriju vozila za privla~enje drva u prorjedama brdskoplaninskih sastojina. (Calculation of some tractive parameters for four vehicles used for wood transportation in mountain forest thinning), Znanstvena knjiga »Skrb za Hrvatske {ume od 1846. do 1996.«, knjiga 2: »Za{tita {uma i pridobivanje drva«, 243–252. FBVA, 2000: CDR »300 Forstmaschinen – Maschinenbeschreibung und Seibstkostenrechnung«. Forstliche Bundesversuchsanstalt – Abteilung für Forsttechnik. FBVA, 2003: CDR »500 Forstmaschinen – Maschinenbeschreibung und Seibstkostenrechnung«. Bundesampt und Forschungszentrum für Wald – Abteilung für Forsttechnik. Horvat D., 1996B: Tractive parameters of four skidders used for wood transportation in mountain forest thinning, ECE/FAO/ILO & IUFRO Seminar on environmentally sound forest roads and wood transportation. Sinaia, Romania, 377–381. Horvat, D., [u{njar, M., 2003: Temeljni sigurnosni i tehni~ki zahtjevi ISO normi za konstrukciju skidera, studija u okviru projekta »Razvoj, izrada i ispitivanje prototipa speCroatian Journal of Forest Engineering 28(2007)1


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cijalnog {umskog vozila – skidera mase 7 t«, programa TEST Ministarstva znanosti, obrazovanja i {porta RH, 1–98. Horvat, D., Goglia, V., [u{njar, M., 2004: Izvje{}e o ispitivanju nekih tehni~kih i ergonomskih zna~ajki traktorske ekipa`e »FORMET«. [umarski fakultet Sveu~ili{ta u Zagrebu, 1–9. Horvat, D., Goglia, V., [u{njar, M., \uki}, I., 2004A: Izvje{}e o ispitivanju nekih tehni~kih i ergonomskih zna~ajki skidera »Ecotrac 120V«. [umarski fakultet Sveu~ili{ta u Zagrebu, 1–16. Horvat D., Jursik L., Krsti}, I., Nedi}, A., Risovi}, S., Slabak, M., Zajec, Z., Sever, S., 1991: Istra`ivanje svojstava i djelotvornosti hvata~a pri proredama nizinskih {uma Spa~vanskog bazena, Mehanizacija {umarstva 15(11–12): 175–191. Horvat, D., Sever S., 1998: Development and use of environmentally acceptable operating techniques and technologies in Croatia’s forests. Proceedings of the FAO/Austria expert meeting on environmentally sound forest operations for countries in transition to market economies, Ort/Gmunden, Austria, 20 – 27 September 1998, 25–33. Horvat, D., [u{njar, M., Goglia, V., \uki} I., 2004B: Izvje{}e o ispitivanju nekih tehni~kih i ergonomskih zna~ajki prorednog skidera »Ecotrac 55V«, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–13. Horvat, D., [u{njar, M., Toma{i}, @., 2004: New technical and technological solutions in thinning operations of lowland forests. International scientific conference »Forest engineering: New techniques, technologies and the environment«, Lviv, Ukraine, 5 – 10 October 2004. The Ukrainian State University of Forestry and Wood technology, poster summary. Horvat, D., Toma{i}, @., 2003: Comparison between skid trail soil penetration characteristics and tractive performance of adapted farm tractors. Glasnik za {umske pokuse 40: 59–79. Horvat, D., 2004: Prototip skidera mase oko 7 t, Inovacijska `ari{ta, Glasnik odjela za tehnologijski razvitak MZO[ RH, 1(2004)4: 14–15. Horvat, D., [u{njar, M., 2004: Research report of some technical characteristics of tractor assembly FORMET. Faculty of Forestry of Zagreb University, 1–7. Krpan, A.P.B., 2000: Mogu}nosti primjene vrhunskih tehnologija pri iskori{tavanju {uma u Hrvatskoj (Possibilities of implementation of high technologies in forest harvesting in Croatia. Znanstveni skup »Vrhunske tehnologije u uporabi {uma«, Zagreb, 11. travnja 2000., HAZU, Znanstveno vije}e za poljoprivredu i {umarstvo, 45–63. Krpan, A.P.B., Por{insky, T., 2001: Harvester Timberjack 1070 u Hrvatskoj. (Harvester Timberjack 1070 in Croatia). [umarski list 125(11–12): 619–624. Krpan, A.P.B., Por{insky, T., 2002A: Proizvodnost harvestera Timberjack 1070 pri proredi kulture obi~noga bora (Productivity of Timberjack 1070 Harvester in Scotch Pine Thinning). [umarski list 126(11–12): 551–561. Krpan, A.P.B., Por{insky, T., 2002B: Djelotvornost strojne sje~e i izradbe u sastojinama mekih i tvrdih lista~a. Znanstvena studija, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–40. Krpan, A. P. B., Por{insky, T., Ze~i}, @., 2003: Studija o potrebnoj veli~ini zglobnog traktora (skidera) temeljem Croatian Journal of Forest Engineering 28(2007)1

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sastojinskih prilika glavnoga prihoda i primijenjene tehnologije. Znanstvena studija izra|ena u sklopu tehnolo{kog projekta Ministarstva znanosti i tehnologije »Razvoj, ispitivanje i proizvodnja specijalnog {umskog vozila skidera mase do 7 t (TP–C37/2002)«, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–41. Krpan, A.P.B., Por{insky, T., 2004A: Djelotvornost strojne sje~e i izrade u sastojinama tvrdih i mekih lista~a – 1. dio: Promi{ljanje struke o strojnoj sje~i i izradbi drva (Efficiency of Mechanical Felling and Processing in Soft and Hardwood broadleaved stands – Part 1: Attitudes of Forest Professionals towards Mechanical Felling and Processing). [umarski list 128(3–4): 127–136. Krpan, A.P.B., Por{insky, T., 2004B: Djelotvornost strojne sje~e i izrade u sastojinama tvrdih i mekih lista~a – 2. dio: Djelotvornost harvestera u kulturi mekih lista~a (Efficiency of Mechanical Felling and Processing in Soft and Hardwood broadleaved stands – Part 2: Efficiency of harvesters in the culture of soft broadleaf trees). [umarski list 128(5–6): 233–244. Krpan, A.P.B., Por{insky, T., Stanki}, I., 2004: Djelotvornost strojne sje~e i izrade u sastojinama tvrdih i mekih lista~a – 3. dio: Djelotvornost harvestera u prirodnoj prorednoj sastojini tvrdih lista~a (Efficiency of Mechanical Felling and Processing in Soft and Hardwood broadleaved stands – Part 3: Efficiency of harvester in natural thinning stands of hardwood broadleaf species). [umarski list 128(9–10): 495–508. Pi~man, D., Pentek, T., 2003: Tehni~ke zna~ajke sekundarnih {umskih prometnica u karakteristi~nim sastojinskim i stojbinskim uvjetima kao podloga za odre|ivanje pogodnih dimenzija skidera. Istra`ivanje i studija u okviru projekta »Razvoj, izrada i ispitivanje specijalnog {umskog vozila – skidera mase 7 t«, programa RAZUM Ministarstva znanosti, obrazovanja i {porta RH, Studija, 1–39. Por{insky, T., Krpan, A.P.B., Stanki}, I., 2004: Djelotvornost strojne sje~e i izrade u sastojinama tvrdih i mekih lista~a – 4. dio: Okoli{na pogodnost strojne sje~e u prirodnim sastojinama (Efficiency of Mechanical Felling and Processing in Soft and Hardwood broadleaved stands – Part 4: Environmental Suitability of Mechanical Felling in Natural Stands). [umarski list 128(11–12): 655–669. Sever, S., 1993: Stanje i mogu}i razvoj mehanizacije u hrvatskome {umarstvu. Status and Possible Development of Mechanization in Croatian Forestry. Mehanizacija {umarstva 18(1): 3–15. Sever, S., Horvat, D., 1985: »[umski zglobni traktor snage oko 60 kW«, Studija, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–187. Sever, S., Horvat, D., 1992A: Skidders and forwarders database as source and help in determining morphological relationships. Proceedings of IUFRO workshop »Computer supported planning of roads and harvesting«, Feldafing, Germany, 196–200. Sever, S., Horvat, D., 1992B: Logging wheeled tractor databank for assistance in machine family evaluation. Proceedings of IUFRO workshop »Computer supported planning of roads and harvesting«, Feldafing, Germany, 281–288. Sever, S., Puljak, S., 2005: TIBOTRAC FM 03 – prvi hrvatski {umski zglobnik na biodizelsko gorivo, Nova mehanizacija {umarstva 26: 3–12.

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[u{njar, M., 2005: Istra`ivanje me|usobne ovisnosti zna~ajki tla traktorske vlake i vu~ne zna~ajke skidera. Disertacija, [umarski fakultet Sveu~ili{ta u Zagrebu, 1–135.

{umarstvu RH (Present Status of Timber Transport by Track Units in Croatian Forestry), Nova mehanizacija {umarstva 26: 65–70.

Toma{i}, @., Su~i}, @., Slunjski, M., Pola~ek, M., 2005: Ovodobno stanje prijevoza drva kamionskim skupovima u

Sa`etak

Stanje i razvoj mehaniziranosti pridobivanja drva u hrvatskom dr`avnom {umarstvu U radu se opisuje ovodobno stanje gospodarenja {umama u Republici Hrvatskoj, s posebnim osvrtom na {ume kojima gospodari trgova~ko dru{tvo »Hrvatske {ume« d.o.o. Zagreb, na ciljeve, zadatke i na~in gospodarenja {umama u dr`avnom vlasni{tvu, na stanje i dosada{nje kretanje broja najzna~ajnijih mehaniziranih sredstava pridobivanja drva. Tako|er se opisuje na~in te aktivnosti kojima »Hrvatske {ume« d.o.o., u suradnji sa [umarskim fakultetom Sveu~ili{ta u Zagrebu, utje~u na smjer razvoja strojeva ii postupaka u pridobivanju drva kao izvornih rje{enja za posebno zahtjevne uvjete prirodnoga na~ina gospodarenja {umama. Od ukupne povr{ine {uma i {umskoga zemlji{ta u Republici Hrvatskoj u dr`avnom je vlasni{tvu 75 % plo{tine, odnosno 2 018 987 ha kojima gospodare »Hrvatske {ume« d.o.o. Preko 50 % radova u gospodarenju »Hrvatske {ume« d.o.o. izvode vlastitim proizvodnim snagama i sredstvima. Stoga je razvoj strojeva i postupaka vrlo bitan preduvjet pobolj{anja poslovne uspje{nosti u slo`enim terenskim prilikama, posebno obilje`enim posebnostima na~ina gospodarenja. Pri tome se mogu izdvojiti ~etiri glavna mjerila u zahtjevima pogodnosti, odnosno prikladnosti tehni~ko-tehnolo{kih rje{enja: Þ okoli{na pogodnost Þ djelotvornost Þ sigurnost Þ ergonomska pogodnost. Ta su mjerila djelomice oblikovana poznatom propisano{}u suvremenih me|unarodnih normi, primjenjivih za uvjete u Republici Hrvatskoj, a djelomice i samom posebno{}u uvjeta gospodarenja. Utjecaj »Hrvatskih {uma« na zadovoljavanje navedenih zahtjeva te izravno sudjelovanje u razvoju prikladnih tehni~ko-tehnolo{kih rje{enja za odre|ene uvjete prikazani su na primjerima razvoja dviju vrsta skidera i traktorskih ekipa`a za prorede nizinskih {uma. Ti se zahtjevi ispunjavaju preko zadataka znanstvenoistra`iva~kih projekata i suradnje sa [umarskim fakultetom Sveu~ili{ta u Zagrebu te postavljanjem zahtjeva i suradnjom s doma}im proizvo|a~ima strojeva i opreme. Klju~ne rije~i: Hrvatske {ume d.o.o., prirodne {ume, razvoj strojeva i tehnologija, skideri, traktorske ekipa`e

Authors’ addresses – Adresa autorâ: Darko Beuk, MSc. e-mail: darko.beuk@hrsume.hr @eljko Toma{i}, MSc. e-mail: zeljko.tomasic@hrsume.hr »Hrvatske {ume« d.o.o. Zagreb Headquaters Zagreb Farka{a Vukotinovi}a 2 HR-10000 Zagreb CROATIA

Received (Primljeno): January 8, 2006 Accepted (Prihva}eno): March 8, 2007

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Prof. Dubravko Horvat, PhD. e-mail: horvat@sumfak.hr Faculty of Forestry, University of Zagreb Department of Forest Engineering Sveto{imunska 25 HR-10 000 Zagreb CROATIA Croatian Journal of Forest Engineering 28(2007)1


Subject review – Pregledni ~lanak

Recent developments in forest traffic way construction in Slovenia Robert Robek, Jaka Klun Abstract – Nacrtak After a decade of regression in forest engineering a distinct increase in skidding trail construction and intentional revival of road constructions in state forests have occurred since the year 2000. In this paper novelties and trends in forest traffic way construction in Slovenia are described. Improved procedures for operational road planning and integration of forest traffic ways into relevant national legislation represent major professional achievements. The main barriers related to forestry infrastructure projects are capital weaknesses, short term orientation and poor cooperativeness of private forest owners. In the future we shall have to introduce and implement technical procedures as well as harmonize the legislative framework with financial measures to encourage forest owners to better cooperation, long-term oriented investments and complex technological solutions. Keywords: forest engineering, legislation, forest road, Slovenia, traffic way

1. Introduction – Uvod Forest traffic ways are a means to achieve the objectives of multipurpose-forest management. Slovenian society and forestry profession have opted for intensified production and use of wood as a domestic renewable natural source. These objectives, however, will not be attained without constructing new and reconstructing old forest traffic ways. Forest traffic way construction is a traditional forestry activity in Slovenia, involving planning, design, construction and maintenance of forest roads, skidding trails and fire-fighting forest ways. Although some significant social, economic and technological shifts have taken place in the last 15 years in Slovenia, they have been unfavourable as far as forest engineering is concerned. In spite of it, a series of successful as well as unsuccessful novelties have been introduced. This article presents: Þ construction of forest traffic ways in Slovenia after 1970, Þ the current conditions in construction of forest roads in Slovenia, and Þ substantiates the recommendations for the development of forest engineering.

2. Work methods – Metode rada During our study of the completed construction projects, data on two-year reports on the state of Croatian Journal of Forest Engineering 28(2007)1

machinery and efficiency in forest exploitation were taken into consideration for the period 1970–1992, as well as reports by the Slovenian Forest Service (SFS) on forests for the post-1992 period. The sources of data on the planned constructions were the district forest-management plans for the period 2001-2010. The financial aspects of the present investment projects concerning forest road construction were analysed by the pattern of So{ko gozdno gospodarstvo Tolmin d.d. (SGG) for the period 1999–2005. Development, introduction and evaluation of the novelties in the sphere of forest road construction were implemented during our monitoring of four practical cases of forest traffic way construction from its very concept to its use. For the study cases, the project documentation was prepared by SGG as well.

3. Results – Rezultati 3.1 Past and expected dynamic of forest traffic way construction – Dosada{nja i o~ekivana (budu}a) dinamika izgradnje {umskih prometnica In 1970, 5,064 km of forest roads in state and privately owned forests were registered in Slovenia (Remic 1971). The annual construction dynamics after 1970 is presented in Fig. 1.

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In the period 1971–1980, numerous unpaved and public roads were built in Slovenia that enabled access to farms and villages in forested areas. The construction of roads and skidding trails reached its peak in the period 1982–1984, when over 300 km of forest roads were built annually. In the early 1990s, the financing of road construction system broke down, which in turn caused an utter collapse of forest engineering. The poor state of the existing forest traffic ways resulted in the establishment of the system aimed at financing the maintenance of forest roads. In 2000, the Ministry of Agriculture, Forestry and Food (MAFF) launched the first tender for co-financing road forest building and elaboration of project documentation to the total value of ca. 200,000 . The Slovenian Agricultural and Forest Land Fund (AFLF) allocated about 625,000  for the construction of new forest roads. In the last two years, somewhat greater interest by private owners (organised within societies) has been noted in construction of roads and skidding trails. In 2006, all the money offered by the MAFF tender was allotted to private investors. In 2004, we had 4,335 km of forest roads in state owned forests and 8,348 km in other forests (SFS 2005). In 2001, the average openness of Slovenian forests with roads amounted to 20.9 m/ha (SFS 2005). Establishing the infrastructure required also substantial soil movement and disturbance (Fig. 1). The forest road network in Slovenia is not optimal. It is getting increasingly worn out, and the new transport technologies demand certain adaptations to be made in the existing technical elements. The planned construction for the period 2001–2010 (SFS

2004) was 1,077 km of roads and 2,923 km of skidding trails. In the period 2001–2005, the total length of newly built roads reached 80.9 km and 1,846.4 km of newly built skidding trails. In the first five years of the implementation of regional plans, the planned extent of built skidding trails reached 63%, whereas and the planned extent of built roads reached 7.5%.

3.2 Characteristics of road investment projects in the period 2000–2006 – Zna~ajke projekata {umskih cesta u razdoblju 2000 – 2006. According to the European classification of civil engineering structures (SURS 2006), forest roads and ways are classified as facilities of traffic infrastructure. In planning and construction of roads, applicable laws and regulations related to forestry, environmental protection, spatial planning, work, investment and building must be taken into consideration. The direct participators in road construction are the investor, designer, constructor and supervisor. The investor makes all the main decisions, coordinates the activities and delegates various responsibilities. The construction takes place in five phases: specification of initiatives, selection of the optimal variant, implementation of the plan, implementation of the construction itself, and itemized statement of works and acquisition of the operating permit. There are several obstacles in the implementation of the investment project, the highest among them being of financial nature. By analysing 43 projects, the total value of investments into roads in state forests amounts to almost 4 million  for the period 2000–2006. The average

Fig. 1 Average annual extent of constructions and reconstructions in forestry Slika 1. Prosje~ne godi{nje koli~ine radova izgradnje i rekonstrukcije {umskih prometnica 84

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Fig. 2 Direct construction costs for 1 m of forest road Slika 2. Izravni tro{kovi izgradnje {umskih cesta (po m) value of construction works (calculated for the year 2006) in road construction for the analysed projects in the state and private sectors amounts to 65 /m (Fig. 2). A more detailed analysis of costs incurring in construction of forest traffic ways within the framework of 13 projects has shown that the average costs of project documentation for the accessible projects of forest roads as of simple and less demanding civil engineering facilities amounted to 3.2 /m (excl. VAT). During the construction of more forest road longer than 2 km, and skidding trail longer than 1 km, the investor is obliged to provide for professional supervision of the planned construction. The costs of such supervision amount to 1.5–2.5% of the net value of construction works. As a rule, the private investors implement construction supervision on their own or entrust it to corporate bodies that do not fulfil the conditions related to this type of activity. In recent years, more additional costs have been acquired by the above three standard groups of forest road construction costs depending on the type of project and they will be presented further in the text.

3.3 Novelties and trends in forest traffic way construction in Slovenia – Novosti i trendovi pri gradnji {umskih prometnica u Republici Sloveniji 3.3.1 Legislation – Zakonska regulativa The legal basis for the construction of forest traffic ways is the Building and Construction Act (2002) Croatian Journal of Forest Engineering 28(2007)1

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and the related by-laws, particularly directives regarding various demanding, less demanding and simple facilities and conditions for their construction (2004). The sectorial legislation regulates the details that concern permissible special features of forest traffic ways, while all the remaining legislation stipulates the conditions for their construction. The register of the relevant technical construction legislation involves over 100 units (MOP 2006), but the list does not include economic, tax, work, safety or forestry regulations. Such legislation, however, is not suitable from the forestry standpoint as it: Þ equalizes the legal conditions for building on forest plots with that of building on urban plots; Þ prevents affirmation of public interest in construction of forest traffic ways within forest smallholds (indifferent, inaccessible owners); Þ severely limits the autonomy of forestry in the construction of skidding trails, particularly in protected areas; Þ sets different tax rates in construction and maintenance of forest traffic ways; Þ burdens construction with various tasks that disproportionately raise the price of investments; Þ excludes public sector from the entrepreneurial activities of planning and construction supervision. The major achievement in the sphere of sectorial construction legislation is the adoption of rules for forest traffic ways (2004) that introduces the zero line plan, states the minimal technical specifications and categorisation of forest traffic ways and regulates their planning, design, construction and use. Apart from numerous good solutions, the set of these regulations deals quite inadequately with the status of reconstructions and improvements and indistinctly regulates the construction and preparation of skidding trails. 3.3.2 Access development planning – Razvoj planiranja Today, the planning of forest opening is carried out entirely by the Slovenian Forest Service and is divided into framework and operational planning. The first takes place within the framework of forest-management planning at the management unit (MU) level, whereas the operational planning concerns, at the investor’s request prior to the elaboration of project documentation, the area opened up by the planned traffic way. The basic product of forest opening operational planning is the zero line plan, which has been prepared by SFS since 2005 and stipulates the permitted

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type of traffic way and its general course. The analysis of zero line plans for study cases has shown that: Þ the time for the elaboration of zero line plan is proportional to the size of the area and the number of variants; Þ the quality of the plan is highly dependent on the available backgrounds; Þ the major source of costs of the plan is the professional fieldwork personnel; Þ the plans depict the skidding trail network and the estimates of skidding distances quite inadequately. One of the open questions of framework forest opening planning is the selection of competent indicators, especially the optimal road density. According to practical experiences the optimal road density is not a relevant parameter for improving the access to the isolated remote areas. The major future treat regarding traffic way planning is the ignorance of professional foresters in future construction legislation. 3.3.3 Design – Projektiranje Design is an economic discipline of preparing project and technical documentation and representing the investor in various construction matters. In design of forest traffic ways, three levels of documentation complexity are distinguished: for less demanding civil engineering facilities (type A), for simple facilities with non-forestry consents (type B), and for simple facilities (type C). The complexity of project documentation depends on technical elements, the degree of interactions of the planned project with buffer zones and protected areas, and the number of owners and investors. Prior to the construction of every forest traffic way, one has to provide for the availability of land covering the area of the future road as well as the area of influence of the entire project, including the area stemming from minimal distances from abutters. If the investor has the right of ownership over all the plots of land in the area of influence of the planned construction at his disposal, attested land register extracts are to be enclosed to the project documentation, while in case the roadway area of influence is multiproprietary, the investor is obliged to acquire the right of construction with co-investor’s or land use contract with land owners. Individual financial participation is stipulated, in simple cases, with the negotiation method, proportional costs or benefits, or with their combinations in complex situations. Apart from the financial structure, the most difficult issue in the construction project is the question of mediation between landowners and various groups of interest. The multiproprietary road projects

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implicitly require a »spiritus agens« – a person that leads a project on his own initiative over all obstacles. Most often, this is an interested forest owner, only exceptionally the local ranger or project designer. For type A forest road projects, geodetic plan for the project documentation is to be acquired for conceptual solution alone, whereas for others an accurate graphic presentation of the project in view of the abutters is to be acquired, for which DGPS is increasingly used. The price of these services ranges between 800 and 1,500  net for the 2,000–5,000 m long alignments. For all forest road projects, a licensed coordinator for safety and health at work is to be appointed already in the phase of design, whose role is to prepare or revise the safety plan. It is highly practical if the appointed coordinator in the phase of project design is also the coordinator in the phase of actual implementation of works. The coordinator’s appointment is the responsibility of the project designer or constructor. The price of this service ranges between 150 and 400  per individual project. From the initial idea to the beginning of a legal construction we need, according to some rough estimates, at least 6 months for type A documentation, 3–4 months for type B, and at least 2 months for the documentation of type C. The proportion of time for administrative works, as a rule, amounts to over 50% for type A, 30–50% for type B, and up to 30% for type C, although only in cases when there are no conceptual complications and if all the involved keep to the stipulated time limits which, however, is more the exception than the rule. Any delays and unnecessary costs in the preparation of project documentation are best avoided with the so-called phase approach, where the concluding components of project documentation are developed gradually. The market of design services in the sphere of forest road construction is poorly developed. 3.3.4 Construction – Izgradnja The construction phase begins with the selection of the most favourable constructor. If the public sector is involved, public invitation to tenders is made. Construction in concession forests is carried out by concessionaires as per prices stipulated by project documentation. Private investors, too, are trying to save money within the construction phase. The prices of construction services offered by private constructors are on average by up to 15% lower for comparable works than those of concessionaires with their own personnel. The quality of works carried out in state forests is higher, the guaranteed deadlines for the works carried out by concessionaires are longer, whereas maintenance costs for the roads built in state Croatian Journal of Forest Engineering 28(2007)1


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forests are lower. A comparison of the structure of costs of the main construction subphases for the studied alignments with the available data shows that about a half of construction costs are incurred by earthworks (Fig. 3). The second highest costs involve the preparation of pavement, which encloses construction of roadside ditches and drains. The share of costs of facilities varies a great deal and depends on the actual conditions on road alignments. Shorter roads are not necessarily cheaper per unit length. Today we are constructing roads, which are actually by at least 30% more expensive, on average, than those in the 1970s and by over 90% more expensive than those built in the 1980s. The rise in prices has been expected, considering that the average terrain conditions, in which roads are built today, are by far more demanding than in the past. On the other hand, it could be expected that the service market would mitigate the rise of prices to a somewhat greater extent. This, however, has not happened at all. The reasons for such state of affairs could be partly ascribed to the small extent of constructions carried out and to the fact that in accordance with the new regulations the constructors are liable to repair the damages inflicted to roads within the guaranteed deadline at their own expenses. In the guaranteed period, this kind of extent of works reaches 3–8% of the value of construction works and is, as a rule, included in construction costs. Although the prices of construction works in forestry are lower than those of comparable works in public road construction, we estimate that we still have about 10% of manoeuvring space in construction costs, whereas

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the possible differences are due to the smaller quality of facilities or inferior »post-sale services«. In the last ten years, the technology of forest road construction has not changed substantially. Most of the works are carried out by diggers (with the power of over 100 kW), and practically no blasting is practised any more. The most noticeable change is the simultaneous presence of diggers, separators and road rollers at working sites. There are more and more longitudinal transports of the excavated material of up to 1 km, which are direct environmental protection costs. The majority of roads built in the 1970s and 1980s ran across less demanding terrain and needed no special facilities. Today’s non-open forests are situated, as a rule, in constructionally extremely difficult terrain, where the supporting, propping, drainage and bridging facilities follow each other. Although technical elements of such facilities are stipulated in project documentation, they cannot be foreseen to the last detail. In spite of a good provision of services concerning construction mechanization, there are only few high quality constructors in the country. This is why the need for supervisors, who can provide for good quality of construction and in most cases compensate for their costs, is becoming increasingly great. 3.3.5 Operation permit and utilisation regime – Uporabna dozvola i pravila uporabe The facilities built on the basis of construction permits cannot be utilised without operation permits. To acquire the latter, suitable technical documentation (the project of the works carried out or the

Fig. 3 The structure of calculated construction costs in some forest road projects Slika 3. Struktura tro{kova izgradnje nekih projektiranih {umskih cesta Croatian Journal of Forest Engineering 28(2007)1

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designer’s statement that the facility was built in accordance with the project for construction permit) and geodetic plan of the new condition of the land must be obtained. Furthermore, a technical inspection of the facility is to be made by administrative body, which issues the operation permit. The price of technical documentation is from 20 to 35% of the project documentation value. The price of geodetic plan depends on the available backgrounds. If the geodetic plan is made for the acquisition of the project documentation, the price of the geodetic plan of the new condition of land in the geodetic plan for entry in the register of facilities is 800–1,000 , otherwise its price is two to three times higher. For the roads built as simple and less demanding facilities, which we wish to include in the forest road network and into the system of its maintenance, a professional technical inspection by SFS is also needed. This inspection, however, does not replace technical inspection carried out by administrative body. The operation permit is followed by the final account of works, which during the construction in natural environment often deviates from the estimated and contract values. The wearisome negotiations in the evaluation of additional works can be best avoided with a consistent keeping of construction diary and with construction supervision. The costs of authorized supervisor are, as a rule, smaller than the unfounded demands by constructor. The forest road utilisation regime is stipulated by SFS in cooperation with forest owners. From the aspect of public significance of forest roads, the most disadvantageous measure of limiting the utilisation of forest roads is their closing with barriers. The latter, however, are simply unavoidable in certain cases.

4. Discussion and Recommendations – Rasprava i preporuke The 1990s were rather dry for the Slovenian forest engineering. At that time, the professional and administrative posts were occupied by people whose motto was that forest transport-network construction should be tackled as gently and as cheap as possible. In general, this is right, but in specific situations the decisions should be made in accordance with the facts dictated by functional units, growing stock, skidding distance and the extent of the area of influence in the multipurpose-forest opening. In multipurpose forests with the growing stock of over 250 m3/ha and with the average skidding distance exceeding 800 m, a road is a technological necessity. In high quality forests with substantially higher growing stock, this holds true for the average skidding

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distance of up to 500 m as well. If we are dealing with smaller districts and less profitable forests, we should consider building unpaved roads – with the expected savings amounting to 20% of the investment. As a rule, the districts with average skidding distance of less than 400 m are opened with skid trails and cable yarding. In the middle of the period covered by district plans from 2001, we can conclude that we shall probably attain the planned objectives regarding the construction of skid trails, but will certainly not be so successful in the construction of forest roads. The situation is particularly unfavourable in privately owned forests, where practically no roads are being built. The reasons for such state of affairs are manifold and concern both the investors and the forestry profession itself. The new social conditions have brought new investors and an utterly different understanding of property. In this paper we have shown that the state is an example of the owner that has become aware of the need to invest in forests with relative construction of skid trails and roads. In privately owned forests we are witnessing, by contrast, a predominance of skid trail construction with no motifs for long-term investments and lesser environmental consequences. While it is true that in our country smallholds prevail and that private owners are capital-weak, we can witness a fairly low degree of their environmental awareness and readiness for financial participation in various infrastructural projects. Construction of forest roads is, irrespective of ownership, no doubt in public interest. And the owners justifiably expect the state to cooperate in their investment intentions. In the construction of skid trails and roads, the forestry profession has not succeeded, since 1993, in establishing a system of building forest traffic ways, but has been mainly concerned with adapting to the prescribed legislative framework. In contrast to the maintenance of roads, where the conditions in the mid-1990s virtually enforced the formation of the system, we have the established construction practice as follows: Þ set of regulations that are giving preference to the form of documentation over its contents; Þ professional services that are finding it increasingly difficult to implement high quality constructional solutions; Þ financial instruments that are absolutely too small, unpredictable and ineffective. If we wish to increase the extent of wood production processes in the period 2007–2013 and to retain the high level of environmental sustainability, we have to continue with a steady construction of Croatian Journal of Forest Engineering 28(2007)1


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skidding trails and to encourage intensely the construction of roads in places where they are truly needed. The technical solutions introduced in the previous period are not only mostly unsuitable, but there is also a lack knowledge and will to implement them. In the future we have to continue with the development of technical and administrative procedures in the way that will encourage the investors to participate with integral solutions and long-term investments. The main professional challenges in the construction of forest traffic ways in the ensuing period are: Þ to implement the zero line plan as a compulsory professional product for all districts, where new major roads or reconstructions are to be built; Þ to substantiate and implement the instrument that will enable a just affirmation of public interest during the construction of forest roads in multipurpose forests in case of inaccessible or uninterested owners; Þ to adapt the project and technical documentation to the technical requirements and environmental consequences of the constructions carried out; Þ to rationalize the implement the construction works on the basis of the actual costs that reflect the project solutions and the actual field conditions; Þ to increase the amount of financial incentives in all construction phases and to differentiate them per development priorities (associating of forest owners, montane areas, state/private projects …). By conquering the above stated challenges, the multitude of procedures in forest road construction would become more transparent, manageable and attractive to potential investors. By adding the key solutions to the existing legislation, the so-called »construction system« would be acquired, which would enclose and balance the solutions in the sphere of new constructions, reconstructions and rehabilitation of all built forest traffic ways. The establishment of the »construction system« building is not the matter of a single institution but a

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lasting task of all professional and administrative services in Slovenian forestry. The solutions must be first of all prepared, then adjusted within the forestry profession, implemented within other relevant services and monitored, then differences critically judged and adapted to new circumstances. The construction system can be shaped either gradually or radically. The first approach tackles the problems from the smaller to the more complex ones. The other approach changes only one of the basic items of the present arrangement of this sphere and causes changes in most of organizational and financial solutions. More suitable for our conditions is the gradual scenario, although the radical approach cannot be totally excluded either. We can opt for it on our own, or it may be imposed on us by others, as a result of our mistakes or professional inertia.

5. References – Literatura Ministrstvo za okolje in prostor (MOP), 2006: URL: http:/ /www.sigov.si/mop/ Remic, C., 1971. Stanje mehanizacije v izkori{~anju gozdov SR Slovenije koncem leta 1970. Biotehni{ka fakulteta, In{titut za gozdno in lesno gospodarstvo Slovenije, Poslovno zdru`enje gozdnogospodarskih organizacij, Ljubljana, 26 p. Statisti~ni urad Republike Slovenije (SURS), 2006: CC_SI – Enotna klasifikacija vrst objektov. URL: http://www.stat. si/klasje/tabela.aspx?cvn=2188 Zavod za gozdove Slovenije (ZGS), 2004: Podatki iz obmo~nih na~rtov 2001–2010. Zavod za gozdove Slovenije, CD, 2004. Zavod za gozdove Slovenije (ZGS), 2005: Poro~ilo Zavoda za gozdove Slovenije o gozdovih za leto 2004.- ZGS, Ljubljana, p. 44–53. 2002. Zakon o graditvi objektov. Uradni list RS {t. 110/02, 97/03-odl. US, 41/04. Uradni list RS 114-4980/2003: Pravilnik o vrstah zahtevnih, manj zahtevnih in enostavnih objektov, o pogojih za gradnjo enostavnih objektov brez gradbenega dovoljenja in o vrstah del, ki so v zvezi z objekti in pripadajo~imi zemlji{~i. Uradni list RS 104/2004: Pravilnik o gozdnih prometnicah.

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Sa`etak

Suvremeni razvoj {umskih prometnica u Sloveniji [umska je prometna infrastruktura nu`na pri vi{efunkcionalnom gospodarenju {umskim ekosustavima. Tako|er je jedan od strate{kih ciljeva slovenskoga dru{tva i {umarske struke pove}anje proizvodnje i uporabe drva, {to je nemogu}e posti}i bez izgradnje novih i rekonstrukcije postoje}ih {umskih prometnica. Uspostavljanje mre`e {umskih prometnica, tradicionalne {umarske aktivnosti u Sloveniji, obuhva}a planiranje, projektiranje, izgradnju i odr`avanje {umskih cesta, traktorskih putova i protupo`arnih {umskih prometnica. U radu se prikazuje kretanje dinamike izgradnje {umskih cesta i traktorskih putova od 1971. do 2006. godine. Izvori su podataka dvogodi{nja izvje{}a (od 1970. do 1992. godine) te godi{nja izvje{}a Slovenske {umarske agencije (Slovenian Forest Service) od 1992. godine do danas. Kao izvore podataka za planirane radove izgradnje i rekonstrukcije {umskih prometnica koristili smo se osnovama {umskih podru~ja za razdoblje 2001 â&#x20AC;&#x201C; 2010. godine. Financijsku sastavnicu projekata analizirali smo na primjeru {umskoga gospodarstva Tolmin d.d. u razdoblju 1999 â&#x20AC;&#x201C; 2005. godine. Dinamika izgradnje {umskih cesta s gornjim strojem i {umskih cesta bez gornjega stroja, rekonstrukcija {umskih cesta, te izgradnja i rekonstrukcija traktorskih putova od 1971. pa do 2006. godine prikazane su na slici 1. Najvi{e je {umskih cesta s gornjim strojem (vi{e od 300 km godi{nje) gra|eno izme|u 1982. i 1984. godine. Po~etkom devedesetih godina postoje}i je sustav financiranja izgradnje i odr`avanja {umskih cesta do`ivio svoj potpuni slom. Tijekom 2000. godine Ministarstvo poljoprivrede, {umarstva i prehrane raspisuje natje~aj za sufinanciranje projektiranja i izgradnje {umskih cesta u vrijednosti 200 000 . Iste godine Slovenski fond za poljoprivredno i {umsko zemlji{te usmjerava 650 000  za izgradnju novih {umskih cesta. Posljednje dvije godine zabilje`eno je ne{to ve}e zanimanje privatnih {umovlasnika za izgradnju {umskih cesta i traktorskih putova (potpuni iznos koji je spomenuti Fond izdvojio 2006. godine ulo`en je u otvaranje privatnih {umoposjeda). Prosje~na je otvorenost svih slovenskih {uma {umskim cestama 2001. godine iznosila 20,9 m/ha i nije optimalna. U 2004. godini Slovenija je imala 4335 km {umskih cesta u dr`avnim i 8348 km {umskih cesta u privatnim {umama. Treba provoditi daljnje otvaranje, ali i rekonstrukciju {umskih prometnica. Sukladno osnovama {umskih podru~ja do 2010. godine trebalo bi izgraditi 1077 km {umskih cesta i 2923 km novih traktorskih putova. Od 2001. do 2005. godine izgra|eno je 80,9 km {umskih cesta (ostvareno je 7,5 % plana) i 1846,4 km traktorskih putova (ostvareno je 63,0 % zacrtanoga plana). U privatnim {umama {umske ceste gotovo i nisu gra|ene. Analizirana su 43 glavna projekta {umskih cesta, a rezultati su prikazani na slici 2. Prosje~na cijena izgradnje iznosi 65 /m (65 000 /km), a ukupna je vrijednost svih projekata blizu 4 milijuna eura Cijena izrade glavnoga projekta (bez PDV-a) iznosi 3,2 /m (3200 /km). Za {umske ceste duljine ve}e od 2 km i traktorske putove duljine preko 1 km nu`no je imenovati nadzor ~ija je cijena od 1,5 do 2,5 % od ukupne neto vrijednosti investicije. Zakonska osnova za izgradnju {umskih cesta je Zakon o gradnji objekata (2002) i Pravilnik o {umskim prometnicama (2004). Iako je Zakon o gradnji objekata dobro rije{io neka dotad nerije{ena pitanja povezana sa {umskim prometnicama: nultu liniju, minimalne tehni~ke uvjete, kategorizaciju {umskih prometnica, proceduru planiranja, projektiranje izgradnje i odr`avanja, neke su stvari ostale nedore~ene, npr. rekonstrukcija {umskih prometnica, izgradnja i popravak traktorskih putova i dr. Planiranje je {umskih prometnica pod ingerencijom Slovenske {umarske agencije, a dijeli se na generalno i operativno planiranje. Rezultat je operativnoga planiranja nulta linija koja okvirno definira trasu budu}e {umske ceste. Jedno od otvorenih pitanja koje pri generalnom planiranju treba rije{iti jest optimalna gusto}a {umskih cesta; naime prema prakti~nomu iskustvu optimalna gusto}a {umskih cesta nije pouzdan parametar za pobolj{anje pristupa udaljenim i izoliranim {umskim podru~jima. Pri projektiranju {umskih prometnica, sukladno tehni~kim zna~ajkama projektiranoga objekta, stupnju interakcija projektiranoga objekta i za{ti}enih podru~ja te broju {umovlasnika i investitora, mogu se razlu~iti tri stupnja slo`enosti projektne dokumentacije (A, B i C). Od po~etne ideje do legalnoga zapo~injanja s izgradnjom (dovr{etka i prihva}anja projekta) za tip A treba minimalno 6 mjeseci (50 % vremena otpada na administrativne poslove), za tip B minimalno 2 do 4 mjeseca (30 % vremena odlazi na poslove administracije), a za tip C minimalno 2 mjeseca (do 30 % vremena tro{i se na administrativne poslove).

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Postupak izgradnje zapo~inje odabirom najpovoljnijega izvo|a~a radova. Ako se radi o ostvarivanju projekta u dr`avnim {umama, raspisuje se javni natje~aj. Uglavnom je kakvo}a izgradnje {umskih cesta, uz kra}e i po{tivane rokove, bolja u dr`avnim {umama. Tako|er su u dr`avnim {umama ni`i tro{kovi odr`avanja {umskih cesta. Ra{~lamba strukture tro{kova izgradnje za deset odabranih projekata {umskih cesta prikazana je na slici 3. Danas je, u prosjeku, cijena izgradnje {umskih cesta 30 % ve}a nego sedamdesetih godina i 90 % ve}a nego osamdesetih godina pro{loga stolje}a. Razlog le`i ponajvi{e u ~injenici kako su tereni na kojima se ceste grade danas puno te`i nego u pro{losti, a zahtjevi za za{titu okoli{a puno stro`i nego {to su bili prije. Prije deset godina postupci izgradnje {umskih cesta nisu se zna~ajnije mijenjali. Glavnina se radova obavlja bagerima snage preko 100 kW, a nadzorni in`enjeri imaju va`nu ulogu jer unato~ dobroj mehanizaciji izvo|a~i radova vrlo ~esto ne po{tuju detaljno izra|ene projekte. Zaklju~ke o potrebi otvaranja odre|enoga {umskoga podru~ja {umskim cestama treba donijeti ovisno o namjeni {uma, drvnoj zalihi, postoje}oj srednjoj udaljenosti privla~enja drva. Op}enito se mo`e zaklju~iti da je u gospodarskim {umama s izra`enim op}ekorisnim funkcijama te drvnom zalihom preko 250 m3/ha i srednjom udaljenosti privla~enja preko 800 m izgradnja {umskih cesta tehnolo{ka nu`nost. U vrijednim {umama s bogatijom drvnom zalihom treba graditi {umske ceste ako srednja udaljenost privla~enja iznosi vi{e od 500 m. Ako je rije~ o neotvorenim manjim {umskim podru~jima s ni`e profitabilnim {umama, treba razmisliti o gradnji {umskih cesta bez gornjega stroja. U {umama sa srednjom udaljenosti privla~enja ispod 400 m treba graditi traktorske putove (kada se koriste zglobni traktori) ili koristiti {umske `i~are. Dr`ava je svjesna potrebe daljnje izgradnje {umskih prometnica kao dugoro~no isplative investicije. U privatnim pak {umama prevladavaju traktorski putovi i trenuta~no nema motiva za dugoro~no isplativo investiranje u {umske ceste. Od dr`ave se o~ekuje pomo} pri ostvarivanju zahtjevnijih infrastrukturnih projekata (izgradnja {umskih cesta). U budu}nosti treba nastaviti s razvojem tehni~kih i administrativnih procedura koje }e potaknuti investitore na zajedni~ka, me|usobno povezana i dugoro~no isplativa ulaganja. Nu`no je izraditi i postoje}im zakonskim propisima, radi rje{avanja brojnih otvorenih pitanja povezanih s izgradnjom, rekonstrukcijom i popravcima {umskih prometnica, dodati tzv. »sustav izgradnje {umskih prometnica«. To je posao koji zajedni~ki trebaju odraditi sve sastavnice slovenskoga {umarstva, a pri tome je mogu} postupan ili radikalan pristup. Podr`ava se postupno rje{avanje problema od jednostavnijih ka slo`enijima. Klju~ne rije~i: {umarsko in`enjerstvo, zakonodavstvo, {umske ceste, prometnice

Received (Primljeno): December 20, 2006 Accepted (Prihva}eno): February 18, 2007 Croatian Journal of Forest Engineering 28(2007)1

Authors’ address – Adresa autorâ: Robert Robek, MSc. e-mail: robert.robek@gozdis.si Jaka Klun, BSc. e-mail: jaka.klun@gozdis.si Slovenian Forestry Institute Department of Forest Technique and Economics Ve~na pot 2 1000 Ljubljana SLOVENIA

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Subject review – Pregledni ~lanak

Forest road network in the Republic of Croatia – Status and perspectives Tibor Pentek, Hrvoje Neve~erel, Dragutin Pi~man, Tomislav Por{insky Abstract – Nacrtak Forest traffic infrastructure is one of the basic preconditions for good quality forest ecosystem management. Since 1991, when the Republic of Croatia gained independence and the company Hrvatske {ume d.o.o. Zagreb (then Public Enterprise Hrvatske [ume Zagreb) was founded, a large amount of financial resources has been invested in the construction of new and the maintenance and repair of the existing forest roads. Despite considerable past investments in this forestry segment, many more kilometres of forest roads will have to be built until optimal forest openness is achieved. This article analyzes the situation with regard to forest roads in Croatia and focuses on the current state of openness, planned openness, annual construction plans, average construction costs, design costs and others. Problems occurring in the procedure of opening up forests (planning, design, construction with supervision and maintenance) are defined and some basic guidelines for their solution proposed. Keywords: forest roads, planning, design, construction, maintenance, costs, Croatia

1. Introduction and Research Topic – Uvod i problematika istra`ivanja Forest traffic infrastructure can be divided into three groups: primary, secondary and special-purpose infrastructure. This paper deals with primary and secondary forest traffic infrastructure. Primary forest traffic infrastructure comprises all truck forest roads – haul forest roads (TFR) and those public roads (PR) which can be used for forest operations (as a rule these are lower-level public roads). Secondary forest traffic infrastructure is made up of skid roads (SR) and skid trails (ST). Skid roads, like truck forest roads, are construction amenities of a permanent character, whereas skid trails are formed by repeated passage of a machine along the same route without any construction work and are temporary in character. Planning, design (field and office part), construction with supervision, and maintenance are essential components of a complex procedure of establishing an optimal network of primary forest traffic infrastructure in the field (Pentek et al. 2004b). The core elements in the establishment of an optimal network of secondary forest roads in the field include planning, construction with supervision and repairs. These operation stages are closely intertwined and insepaCroatian Journal of Forest Engineering 28(2007)1

rably linked, which means that one operation stage cannot be started unless the previous one has been successfully completed. From the standpoint of modern forest ecosystem management, an ideal solution is to plan SR simultaneously with planning TFR. This makes it possible to predict in advance the preliminary routes of both primary and secondary forest roads and their category (which is characterized by given technical features and construction standards), evaluate construction costs and subsequent maintenance (repairs), and define annual plans of construction dynamics in accordance with management plans, felling plans, profits and losses, etc. (Pentek et al. 2006). In order to make quality planning of all forest operations, and in particular of harvesting and opening up forests with forest roads, it is necessary to review the existing transportation infrastructural resources. For this reason, a cadastre of primary forest traffic infrastructure was set up for state forests in Croatia within the company Hrvatske [ume Zagreb (hereinafter »H[«), conclusively with December 31, 2001. The methodology of its design was developed in cooperation with the »H[« and the Department of Forest Engineering of the Faculty of Forestry, University of Zagreb (Anon. 1998b). The cadastre consists of textual (tables) and pictorial (maps) parts.

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Once a cadastre of primary forest traffic infrastructure is established, it should be reviewed at the end of the year and updated with new components built in the course of the current year. At present there is no cadastre of secondary forest traffic infrastructure at the level of the company »H[«; in other words, the components of permanent character (skid roads) are missing. Pentek et al. (2003) propose a methodology of drawing up a secondary forest road cadastre, prepare a cadastre for the Management Unit Veprina~ke [ume, Opatija Forest

Administration, Buzet Forest Office, and list its advantages. After the potential route of a TFR is positioned in the field using a GPS device, the axle polygon of the designed TFR is fitted in; this is a transition from the planning stage to the designing stage (Pentek et al. 2004b). Designing consists of two temporally and spatially separated subphases: field subphase and office subphase. All parameters necessary for a detailed design of the TFR are collected in the field using geodetic measuring stations. The collected data are

Fig. 1 Map of the Republic of Croatia with marked Forest Administrations Slika 1. Karta Republike Hrvatske s ucrtanim U[P 94

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processed with the computer programme »CESTA«. The TFR detailed design, signed by a certified engineer, is submitted for verification to County Offices of State Administration of Environmental Protection, Physical Planning and Construction. After verification, the design is put into operation. Forest roads are built by both the »H[« (their own capacities) via their operational units »Gra|evinarstvo« (located in 8 out of 16 Forest Administrations), and by private entrepreneurs. Private entrepreneurs compete for jobs in public bids (best bid), in which the highest (upper) investment cost is cited (in line with the bill of charges from the detailed design), while prospective contractors submit their bids, together with other requested documentation, in writing. Bid opening is public. The investor and the contractor sign a Service Agreement and a Protocol on the Receipt of the building site, which introduces the contractor into work. The investor designates a supervising engineer and the contractor designates their representative on the building site. After a truck forest road has been built, it should be regularly and periodically maintained so that the required quality of the forest transport network is retained. The higher the category of a truck forest road is, the more frequent and extensive periodic maintenance jobs, and vice versa (Pentek et al. 2006).

T. PENTEK et al.

2. Goal and Research Methods – Cilj i metode istra`ivanja The goal of research is to analyze the situation relative to forest roads in the Republic of Croatia, recognize and clearly define the detected problems according to the stages of optimal forest road network establishment in the field (planning, design, construction with supervision and maintenance-repair), and propose procedures for their solution.

3. Research Area – Podru~je istra`ivanja The area of research embraces forests and forestland in the Republic of Croatia managed by the company »H[« (2,018,987 ha or 75.1%) through their sixteen Forest Administrations (hereinafter: FA). Natural forests account for 95% and artificially raised cultures and plantations for only 5% of the above area. Forested areas in the continental part of Croatia cover 59% and forests on karst 41% of the area.

4. Research Results – Rezultati istra`ivanja 4.1 Current situation related to forest road network in the Republic of Croatia – Postoje}a situacija glede {umskih prometnica u Republici Hrvatskoj 4.1.1 Primary forest openness – Primarna otvorenost {uma

Fig. 2 Minimal, planned and targeted openness for different relief areas in the Republic of Croatia Slika 2. Najmanja, planirana i ciljana otvorenost za razli~ita reljefna podru~ja Republike Hrvatske Croatian Journal of Forest Engineering 28(2007)1

Figure 2 shows the minimal prescribed openness in 1990 ([iki} et al. 1989), planned openness by 2010 (Anon. 1997a) and targeted openness by 2020 (Pentek et al. 2006) for different relief regions in the Republic of Croatia. This allows a comparison between varying kinds of primary openness and existing primary openness. The above openness values are only preliminary guidelines which should be followed in the absence of better ones, but they should not be blindly adhered to, because the opening up of any management unit, watershed or gravitational area is a specific problem that calls for specific solutions concordant with the concrete stand and site conditions (Pentek et al. 2005). Table 1 shows existing primary openness in Forest Administrations (FA) calculated as average openness, although the majority of FA are characterized by a combination of different relief areas. The years in which the cadastres were updated differ for some FA; consequently, the present situation, particularly in those FA that are being intensively opened up by

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Table 1 Existing primary openness in the Republic of Croatia (according FA) Tablica 1. Postoje}a primarna otvorenost U[P Forest Administration Uprava {uma podru`nica Vinkovci

Osijek

Na{ice

Po`ega

Bjelovar

Koprivnica

Zagreb

Sisak

Karlovac

Ogulin

Delnice

Senj

Gospi}

96

Category Roads Kategorija ceste Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno

Length Duljina km – 397.03 397.03 – 418.12 418.12 – 1,624.82 1,624.82 – 707.74 707.74 – 1,838.37 1,838.37 – 793.15 793.15 – 802.95 802.95 – 549.06 549.06 – 958.82 958.82 – 865.82 865.82 – 1,989.93 1,989.93 – 1,612.98 1,612.98 – 1,904.22 1,904.22

Effective length Ulazi u otvorenost km 91.61 349.95 441.56 82.05 298.06 380.11 140.74 1,352.38 1,493.12 85.19 598.58 683.77 282.34 1,216.78 1,499.12 309.21 664.03 973.24 419.32 641.90 1,061.22 135.75 421.00 556.75 99.63 674.36 773.99 81.53 718.55 800.08 241.26 1,742.14 1,983.40 137.00 1,033.81 1,170.81 345.00 1,731.11 2,076.11

Forested area Obrasla povr{ina ha 68,173.92

57,286.05

78,537.60

48,714.84

123,633.00

59,040.00

75,354.53

83,906.16

76,782.00

51,902.00

92,437.99

67,688.56

266,324.24

Openness Otvorenost m/ha 1.34 5.13 6.47 1.43 5.20 6.63 1.79 17.22 19.01 1.75 12.29 14.04 2.28 9.84 12.12 5.24 11.25 16.49 5.56 8.52 14.08 1.62 5.02 6.64 1.30 8.78 10.08 1.57 13.84 15.41 2.61 18.85 21.46 2.02 15.27 17.29 1.30 6.50 7.80

Condition Stanje Year – Godina 2003

2002

2003

2003

2003

2003

2004

2003

2003

2002

2003

2001

2005

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Forest Administration Uprava {uma podru`nica

Category Roads Kategorija ceste

Buzet

Public – Javna Forest – [umska Total – Ukupno

Length Duljina km – 434.26 434.26

Public – Javna Forest – [umska Total – Ukupno Public – Javna Forest – [umska Total – Ukupno

– 650.30 650.30 – 15,547.57 15,547.57

Split Nova Gradi{ka

Total »H[« Ukupno H[

Effective length Forested area Ulazi u otvorenost Obrasla povr{ina km ha 289.31 331.97 63,276.36 621.28 No comparable data – Nema usporedivih podataka 64.94 574.79 69,019.25 639.73 2,804.88 12,349.41 1,282,076.50 15,154.29

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Openness Otvorenost m/ha 4.57 5.25 9.82 0.94 8.33 9.27 2.19 9.63 11.82

Condition Stanje Year – Godina 2003

2003

truck forest roads, is much better. A part of the data for FA Split is missing and is therefore not presented here. The total data on the quantity of public roads and truck forest roads, as well as on primary forest openness at the level of the »H[« does not include FA Split. In order to make an in-depth analysis of primary openness and obtain comparable results, the data should be reduced to the level of management unit. The management unit must previously be categorized according to the relief area. The data on primary openness of a particular management unit should also be complemented with the data on the mean skidding distance. This allows for the analysis of the quality of spatial positioning of a TFR. 4.1.2 Engineering operations in the period 2004–2006 in the company Hrvatske {ume – Radovi na niskogradnji u razdoblju 2004 – 2006. na razini poduze}a »Hrvatske {ume« d.o.o. Engineering activities performed by the company »H[« in the period 2004–2006 are given in Table 2. The selected time period is also the period of the present »H[« management board’s activity; thus, the presented data simultaneously show the results of the company’s business policy. Engineering operations are divided into four basic categories: building the lower TFR layer, building the upper TFR layer, TFR maintenance and building SR. An average of 272 km of the lower forest road layer is constructed annually at a cost of 118,134 kn/km on average. Construction work on the upper layer entails 319 km of forest roads at a mean cost of 135,020 kn/km. The average price of one fully completed kilometer of a forest road is 253,154 kn. The real cost of overall FR construction differs consideCroatian Journal of Forest Engineering 28(2007)1

Fig. 3 Share of a particular group of engineering operations within the company »H[« in the period 2004–2006 Slika 3. Udio pojedine skupine radova na niskogradnji u razdoblju 2004 – 2006. na razini poduze}a H[ rably from the planned cost, especially if the real cost is the one cited in the bill of charges of the detailed design, and not the one achieved in a public bid. On average, 3,521 km of truck forest roads are maintained annually (21% of the total quantity of TFR in Croatia according to the available data from the TFR cadastre, also taking into account the TFR in

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Table 2 Engineering activities undertaken within the company »H[« in the period 2004–2006 Tablica 2. Obavljeni radovi na niskogradnji u razdoblju 2004 – 2006. na razini poduze}a H[ Engineering activities – Radovi na niskogradnji Quantity Koli~ina km

2004 2005 2006 Total / average – Ukupno/prosje~no 2004 2005 2006 Total / average – Ukupno/prosje~no 2004 2005 2006 Total / average – Ukupno/prosje~no 2004 2005 2006 Total / average – Ukupno/prosje~no 2004 2005 2006 Total – Ukupno Average – Prosje~no

Value Price Vrijednost Cijena 103 x kn kn/km Lower TFR layer – Izrada donjega stroja [C 251.60 26,788 106,471 173,95 292.43 31,267 106,921 163,14 272.68 38,426 140,920 168,00 816.71 96,481 118,134 505,09 Upper TFR layer – Izrada gornjega stroja [C 229.64 32,471 141,400 133,58 374.36 47,039 125,652 146,48 351.62 49,518 140,828 205,25 955.62 129,028 135,020 485,31 TFR Maintenance – Odr`avanje [C 3,049.07 34,965 11,467 1,267,15 3,287.52 37,880 11,522 1,257,43 4,226.50 48,119 11,385 1,804,20 10,563.09 120,964 11,452 4,328,78 SR Construction – Izgradnja TP 799.11 16,946 21,206 229.93 876.68 18,115 20,663 242.18 952.73 22,567 23,687 249.10 2,628.52 57,629 21,925 721.21 All engineering operations – Svi radovi na niskogradnji 111,170 134,301 158,630 404,101 134,700

the area of FA Split) costing 11,452 kn/km (1 EUR = 7.40 kn). A total of 876 km of skid roads are built every year at an average cost of 21,925 kn/km. The overall value of all engineering work amounts to 134,000,000 kn annually on average, of which over half (51.46%), calculated on the basis of the value of executed work, was accomplished by the company »H[« with their own capacities. In the overall structure of engineering operational costs (Fig. 3), costs of building the upper layer of a TFR (31.93%) account for the highest average share

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Executed with H[ capacities – Obavljeno vlastitim kapacitetima Quantity Value Share Koli~ina Vrijednost Udio 3 m 10 x kn % 19,042 18,850 24,848 62,740

71.08 60.29 64.66 65.03

18,002 22,787 30,692 71,481

55.44 48.44 61.98 55.40

17,461 18,388 24,646 60,495

49.94 48.54 51.22 50.01

3,929 4,252 5,041 13,222

23.19 23.47 22.34 22.94

58,434 64,277 85,227 207,938 69,313

52.56 47.86 53.73 / 51.46

in the period 2004–2006, followed by costs of TFR maintenance (29.93%), then costs of building the lower layer of a TFR (23.88%) and finally costs of building SR (14.26%). 4.1.3 Forest road planning – identifying problems – Planiranje {umskih prometnica – definiranje problema Forest road planning (hereinafter FR) is the first and the most important phase in the optimization procedure, which leads to determining the preliminary route of a FR and allows for a comprehensive Croatian Journal of Forest Engineering 28(2007)1


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solution to the issue of opening up a particular forest area (usually a management unit). This phase of establishing an optimal FR network is often omitted in practice. On the one hand, justification is sought in the non-existence of a Study of Primary Forest Opening and a Study of Secondary Forest Opening, which should define preliminary TFR and SR routes, and on the other hand, there is constant urgency to construct new TFR and SR necessary for the accomplishment of activities set down in Management plans. New preliminary routes of FR in the field are determined imprecisely and no account is taken of the best possible TFR and SR route variants (optimized in terms of all optimization evaluation criteria). In addition, the problem of opening up forests is not solved at the level of management units but partially (usually without any consideration for the existing primary and secondary forest traffic infrastructure). As a result, the targeted mean skidding distances are achieved with the construction of more kilometres of forest roads than necessary. This increases the costs of TFR construction and maintenance in a given area (due to the higher number of kilometres); furthermore, in both horizontal and vertical sense, TFR and SR routes are laid out in such a manner that the unit cost of construction and maintenance (repair) exceeds the cost of TFR and SR routes defined by the basic Study of Primary and Secondary Forest Opening. 4.1.4 TFR design – identifying problems – Projektiranje [C – definiranje problema The basic problems occurring in the procedure of truck forest road design are linked with: Þ The absence of suitable Technical Requirements for Forest Roads, since the effective Technical Requirements for Economic Roads are outdated, incomplete, contradictory and over-general, Þ The non-existence of a Handbook of Truck Forest Road Design, which would clearly and unequivocally respond to all the questions and problems a project engineer encounters in the field or office part of the work, Þ The newly established Croatian Chamber of Forestry and Wood Technology Engineers (hereinafter Forestry Chamber), which is still insufficiently active in the protection of the interests of the forestry profession, Þ The outdated computer programme »CESTA«, used as an official tool for TFR design, Þ Lack of uniformity in the produced TFR designs (form, content, and quality), Þ An insufficient number of well educated forest road project engineers (in terms of annual Croatian Journal of Forest Engineering 28(2007)1

T. PENTEK et al.

volume of planning, design, and supervising activities related to truck forest road construction), Þ The absence of lifelong training of forestry engineers that deal with FR-related problems. 4.1.5 TFR and SR construction and supervision of construction – identifying problems – Izgradnja [C i TP te nadzor gradnje – definiranje problema This operational stage should ensure consistent compliance with project documentation and transfer of the designer’s idea from the paper to the terrain. In order to achieve the conditions that will guarantee compliance with project documentation and a systematic inspection of activities, prior to starting the activities, the axle of a truck forest road should be laid out anew. The following basic problems occur in the process of TFR and SR construction and supervision: Þ Lack of a procedure of licensing operations (technology) and forest road contractors. As a result, contractors are often untrained legal persons who, contrary to the provisions in the effective laws, generally do not employ suitable skilled personnel and do not possess adequate machinery and equipment. The final outcome is forest roads of poor quality and harmful environmental impacts. Þ The non-existence of a professional association of contractors dealing with the construction and maintenance of truck forest roads, which would protect their interests on the labour market, evaluate and assess its members and allow healthy competition. This is the reason that the prices in public bids are formed freely (no binding limits – the only limit is the upper, bid price put forward by the ordering party) and may drop by more than 30% in relation to the realistic, initial price. Later, the contractors often cannot meet the requirements set down in the contracted price, which again results in TFR that do not fully respect detailed designs. Þ In practice, contractors often fail to renew the layout of the route axle of a TFR and mark its cross-sections (although these operations are listed as primary items in cost estimates and bill of charges of any TFR). This renders good quality supervision of work and the transfer of detailed design to the field almost impossible, which again results in a TFR of inferior quality.

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Table 3 TFR plan 2006–2015 and simulated openness in 2015 per FA Tablica 3. Plan izgradnje {umskih cesta 2006 – 2015. i projekcija otvorenosti 2015. godine po U[P Forest Administration Uprava {uma podru`nica

Construction Plan Plan izgradnje

km/10 yrs. – km/10 god. Vinkovci 68.10 Osijek 116.20 Na{ice 105.38 Po`ega 94.70 Bjelovar 100.07 Koprivnica 46.80 Zagreb 172.50 Sisak 55.50 Karlovac 79.80 Ogulin 127.30 Delnice 135.00 Senj 215.88 Gospi} 890.02 Buzet 115.00 Split 566.00 Nova Gradi{ka 102.40 Total »H[« – Ukupno H[ 2,990.65

Value of Work Vrijednost radova kn 15,118,200 25,796,400 23,123,880 21,023,400 22,214,868 10,678,200 38,295,000 12,321,000 17,715,600 20,256,600 29,970,000 44,183,270 135,283,040 17,480,000 86,032,000 22,732,800 542,224,258

Þ Frequent absences of a building site manager (contractor’s employee) on the site, who should manage the construction of the TFR route without consulting the design project. Þ The absence of supervising engineer on the site and the replacement of permanent supervision with temporary supervision. This makes it hard to keep things under control and record the operations not listed in the bill of costs. Once a TFR is built, it is often too late to correct mistakes and rectify irregularities on its route. 4.1.6 TFR maintenance – identifying problems – Odr`avanje [C – definiranje problema After a TFR has been built, it is necessary to conduct permanent and periodic maintenance activities so as to retain the prescribed quality of a primary forest road network. Bellow are the basic problems currently occurring in TFR maintenance, with respect to the fact that TFR maintenance activities in the period 2004–2006 took up an average 40,000,000 kn annually (which is 54% of the value of building the lower and upper TFR layer):

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Existing Postoje}a 6.47 6.63 19.01 14.04 12.12 16.49 14.08 6.64 10.08 15.41 21.47 17.29 7.80 9.82 – 9.27 11.82

Openness – Otvorenost Plan in 2015 Plan 2015. m/ha 7.47 8.67 20.35 15.98 12.93 17.28 16.37 7.30 11.12 17.87 22.92 20.49 11.14 11.64 – 10.75 14.15

Plan in 2015 corrected Plan 2015. – korigirani 7.77 9.28 20.75 16.56 13.17 17.52 17.06 7.50 11.43 18.61 23.36 21.43 12.14 12.19 – 11.20 14.72

Þ The absence of regulations that define the scope of permanent maintenance activities and the frequency and intensity of periodic maintenance activities in accordance with the TFR category; Þ The absence of a methodology of determining the condition of primary forest road infrastructure and the need for maintenance (using samples); Þ The absence of a TFR network maintenance plan at the level of management unit and of a maintenance study for a concrete TFR, Þ The application of equal maintenance standards to all TFR categories.

4.2 Operational guidelines – Smjernice djelovanja 4.2.1 TFR plan for the period 2006–2015 within the company »H[« – Plan izgradnje {umskih cesta u razdoblju 2006 – 2015. na razini poduze}a H[ A ten-year (2006–2015) plan of truck forest road construction is given in Table 3. The construction plan Croatian Journal of Forest Engineering 28(2007)1


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also determines the planned FA accessibility in 2015. Since the main TFR have already been built and those of lower categories are currently under way, we assume that all new TFR will affect openness in their entire lengths. The value of operations was calculated on the basis of planned costs (planned costs of forest fire-prevention roads are 152,000 kn/km and truck forest economic roads 222,000 kn/km). Since the existing cadastre of TFR in the majority of FA was updated in 2003, openness in 2015 must be increased by the average three-year construction plan in each FA. The TFR construction plan contains the following items: annual construction of about 300 km of new TFR; annual construction costs of about 54,000,000 kn; and unbalanced building activities per TFA caused by varying primary openness, different stand and site conditions and the related different harvesting techniques and technologies. 4.2.2 Forest road planning – recommended activities and procedures – Planiranje {umskih prometnica – preporu~ene mjere i postupci An improved procedure of forest road planning requires strict adherence to the following activities and procedures: Þ The need to produce a Study of Primary Forest Opening and a Study of Secondary Forest Opening should be regulated by law. The mentioned Studies of Forest Opening should make up a constituent part of Management plans (in the form of an annex for easier use in the field), and should cover a period of 10 (20) years. Studies of Forest Opening should be approved by a designated commission consisting of experts in the field of forest opening. Þ FR planning entails the use of GIS (a system consisting of integrated geocoded cartographic bases and relation databases, then of algorithms which manage these data, and of procedures for rapid and economic establishment of the changes, which is particularly important for monitoring the dynamics of changes in forestry) and GPS devices (to inventory the existing forest roads, prepare cadastres and transfer preliminary TFR routes, chosen with computer models and simulated on adequate bases, to the field). Þ Studies of Primary Forest Opening and Studies of Secondary Forest Opening should be drawn up by certified forestry engineers – members of the Department of Forest Roads and Forest Construction within the Croatian Chamber of Forestry and Wood Technology Engineers, who are skilled and trained for this task. Croatian Journal of Forest Engineering 28(2007)1

T. PENTEK et al.

Þ All physical and legal persons should take part in the preparation of the Study of Forest Opening (private forest owners, local management and self-management units, competent ministries and institutions); in other words, all those in whose interest it is to participate in making decisions on a particular forestry issue (in this case selecting the routes of future TFR). In West European countries the »public voice« is increasingly being acknowledged. The public takes part, when FR are concerned, in planning procedures but also participates, on an equal footing, in the allocation of construction and maintenance (repairs) costs. 4.2.3 TFR design – recommended activities and procedures – Projektiranje [C – preporu~ene mjere i postupci In order to improve TFR design, the following activities must be undertaken: Þ Create, as soon as possible, new Technical Requirements for Forest Roads with defined basic content components of a detailed TFR design. Every subappendix should be elaborated in detail for the purpose of achieving uniformity and balanced quality of the created project. Þ Urgently prepare a Handbook of Truck Forest Road Design which will provide answers, in one place, to a large number of questions occurring during the designing procedure (both in the field and in the office stage). Þ Appoint managers for special programmes in the Forest Chamber, including a specialist programme Forest Roads and Forest Engineering, who will coordinate, create and implement activities within the Forest Chamber at the level of specialist programmes. One of the prime tasks is also the organization of lifelong education. Þ Design a new computer programme for TFR design which will specialize exclusively in TFR (the currently used programme »CESTA« was originally intended for public road design but was later adjusted for TFR design). Þ Establish a professional, qualified commission entrusted with the revision of the created TFR designs. This will ensure credibility and quality of technical documentation before the construction activities are launched. Apart from forestry experts, the commission should include spatial management experts and civil engineering experts. Þ Consider the creation of detailed SR designs since they, like TFR, represent permanent engineering forest amenities. Past experience shows

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that it is better when forestry professionals themselves set down certain rules than let others do it for them (even at a risk of initial misunderstandings of this practice, it is generally a much better and less painful variant in the long run).

Þ Define the scope of permanent maintenance activities and the frequency and intensity of periodic maintenance activities in accordance with the new TFR categorization in the chapter TFR Maintenance within Technical Requirements for Forest Transportation Network.

4.2.4 TFR and SR construction and supervision of construction – recommended activities and procedures – Izgradnja [C i TP te nadzor gradnje – preporu~ene mjere i postupci

Þ Develop a methodology of sample collection at the level of a management unit, which will allow a rapid and accurate insight into the quality status of the existing TFR network. Together with the TFR category, their current status should provide an entry parameter for determining the amount of maintenance operations.

The recommended activities and procedures aimed at improving the existing situation relating to TFR and SR construction and supervision entail the following: Þ The procedure of licensing operations and contractors related to forest road construction should be initiated via the Forestry Chamber and within the specialist programme Forest Roads and Forest Engineering. It is also necessary to establish a registry of licensed private entrepreneurs dealing with the subject activities (and using licensed machines and equipment). The registry should also contain annual evaluations of entrepreneur quality and reliability (which should, together with other criteria, be taken into account during the selection of the best bidder in public bids). Þ Contractors engaged in the construction, maintenance and repair of forest roads should organize themselves and establish their Trade association, which will protect their interests and ensure fair market competition. Þ The supervising engineer should insist on renewing the layout of the TFR axle route and marking all cross sections in the field before the contractors start working. Þ The building site manager, appointed by the contractor, should be present at the building site at all times (in case of his absence at the building site, the supervising engineer should suspend all construction activities). Þ The supervising engineer should be present at the building site at all times to supervise work, compare it with the detailed design and follow the Engineering Record and Engineering Log. It is recommended that supervision is undertaken by the designer. 4.2.5 TFR maintenance – recommended activities and procedures – Odr`avanje [C – preporu~ene mjere i postupci Improvement of TFR maintenance activities requires the following measures and procedures:

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Þ Draw up annual plans of TFR network maintenance for a particular management unit within the Study of Primary Forest Opening. Þ Prepare a maintenance study for a particular TFR, especially for truck forest roads that require major interventions.

5. Discussion and Conclusive Remarks– Rasprava i zaklju~na razmatranja The establishment of a cadastre of primary forest traffic infrastructure at the level of »H[« is the prime contribution to modern, integrated management with forests in Croatia. Regular cadastre update and the possibility of viewing the current status will ensure even better planning of all forestry operations, and in particular forest opening and harvesting activities. The future cadastre of secondary forest roads, whose preparation methodology has already been defined, will add yet another step towards the quality of forest resource management. The analysis of existing primary openness of Croatian forests managed by the company »H[« reveals considerable differences among FA. Apart from being caused by varying site and stand conditions, these differences are also due to different approaches to primary forest opening using different harvesting techniques and technologies (but also to dissimilar past financial investment possibilities in primary forest road). The majority of FA cannot be classified into one relief area only (lowland, hilly, mountainous or karst); rather, they are a combination of two or more relief areas. For this reason, primary openness within a particular FA should be expressed separately for each relief area. Therefore, no comparisons should be made between current and planned primary openness unless the FA in question is homogeneous Croatian Journal of Forest Engineering 28(2007)1


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in terms of relief (or one type of relief is predominant over a large area). One of the criteria used to evaluate the optimality of the existing FR network and plan future forest opening activities is the technical-technological criterion (Pentek et al. 2004a). Operative terrain classification should be made at the level of Croatia in order to determine the type of optimal harvesting techniques and technologies to be applied in certain terrain and stand conditions. The FR network should be optimized using the operative terrain classification. Existing primary openness should be analyzed at the level of a particular management unit and should be supplemented with compulsory presentation of the mean skidding distance value. Instead of classical primary openness, it is even better to determine relative primary openness (it shows the ratio between open and unopened forest area for targeted mean skidding distance in percentages), which is an indicator of the quality of spatial TFR arrangement. Ever since the public enterprise »Hrvatske {ume« (presently »Hrvatske {ume« Zagreb) was established, substantial financial resources have been invested in TFR construction and maintenance and in TR building and repairs. From 2004 to 2006, engineering activities accounted for an average 134,000,000 kn annually (about 6% of the total revenue of »H[«). In terms of FA, the largest amount of engineering activities were, understandably, undertaken in FA Gospi}: this FA is characterized by poor primary and secondary openness due to being largely situated in demanding terrains in terms of opening up forests and timber harvesting. According to the TFR construction plan for the period 2006–2015, about 300 km of new TFR (lower and upper layer) are planned at an annual construction cost of about 54,000,000 kn (calculated on the basis of planned price). On average, in the period 2004–2006 an annual amount of 75,000,000 kn were invested in the building of lower and upper TFR layers: 272 km of TFR lower layer and 319 km of TFR upper layer were built on average. The difference in the price with approximately equal quantity of new TFR annually indicates that planned prices were too low in relation to the realized building costs. It is realistic to expect that annual TFR building costs will exceed planned costs. The analysis of the 2015 openness plan indicates that the volume of TFR construction should be greater than planned. The present quality of FR planning, TFR design and TFR and SR construction and supervision procedures, as well as TR maintenance is at a much higher level than it was at the beginning of the 1990s. Croatian Journal of Forest Engineering 28(2007)1

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However, a detailed analysis of each stage in the establishment of an optimal forest road network in the field has revealed certain problems, defects, deficiencies, and irregularities. Our effort to identify, pinpoint and describe them, as well as recommend efficient actions for their removal, is geared towards rationalising forest opening costs, improving the quality of forest road network, cutting down on harvesting costs and promoting overall forest ecosystem management of the highest quality. The basic preconditions (legal and organizational ones in particular), highlighted as crucial in earlier debates on the improvement of forest opening procedures, have been met. By this we mean the establishment of the Croatian Chamber of Forestry and Wood Technology Engineers and its separate specialist programme Forest Roads and Forest Engineering. Their establishment provides a framework for positioning this forestry segment within and out of the forestry profession. The foundations have been laid for good developmental possibilities, but we should always be aware of the fact that the final result will for the most part depend on our own resources.

6. References – Literatura Akre, B., 1996: Forest road construction policies, guidelines and codes of practice. Proceedings of the »Seminar on Environmentally sound forest roads and wood transport«, Sinaia (Romania), June 17–22, 1996, p. 153–173. Anon., 1995: Prijedlog izgradnje protupo`arnih prometnica na podru~ju kr{a od 1995. do 1999. godine. J.P. Hrvatske {ume, Zagreb, 1–5. Anon., 1997a: Izvje{}e o problematici gradnje i odr`avanja {umskih i protupo`arnih prometnica i stanju otvorenosti {uma. J.P. Hrvatske {ume, Zagreb, 1–11. Anon., 1997b: Prijedlog metodologije izrade katastra {umskih i protupo`arnih prometnica na podru~ju J.P. Hrvatske {ume, Zagreb, 1–14. Anon., 2002: Forest Road Engineering Guidebook, British Columbia, Ministry of Forests, p. 1–208. Cornell, J., Mills, K., 2000: Forest Road Management Guidebook, Oregon Department of Forestry, p. 1–32. FAO, 1998: A Manual for the planning, design and construction of forest roads in steep terrain, p. 1–188. Pentek, T. 1998: [umske protupo`arne ceste kao posebna kategorija {umskih cesta i ~imbenici koji utje~u na njihov razmje{taj u prostoru. Glasnik za {umske pokuse 35: 93–141. Pentek, T., Pi~man, D., Krpan, A. P. B, Por{insky, T., 2003: Inventory of primary and secondary forest communications by the use of GPS in Croatian mountainous forest.

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Proceedings of International workshop Austro 2003 – High Tech Forest Operations for Mountainous Terrain, October 5–9, 2003, Schlaegl, Austria, University of Natural Resources and Applied Life Sciences Viena, CD-ROM, 1–12.

Pentek, T., Pi~man, D., Neve~erel, H., 2005: Planiranje {umskih prometnica – postoje}a situacija, determiniranje problema i smjernice budu}eg djelovanja. Nova mehanizacija {umarstva 26: 55–63.

Pentek, T., Pi~man, D., Por{insky, T., 2004a: Planning of forest roads in Croatian mountainous forest by the use of modern technologies. International scientific conference on Forest engineering: new techniques, technologies and the environment, Lviv, Ukraine, October 5-10, 2004. Proceeding p. 380–389.

Pentek, T., Pi~man, D., Neve~erel, H., 2006: Planning, designing, construction and maintenance of forest roads in Croatia – problems and recommendations. Proceedings of International Science Conference „Present and Future of Forest Opening-Up and Hydrology, September 21–22, 2006, Sopron, Hungary, p. 92–103.

Pentek, T., Pi~man, D., Neve~erel, H., 2004b: Environmental – ecological component of forest road planning and designing. International scientific conference on Forest constructions and ameliorations in relation to the natural environment, Technical University in Zvolen, Slovakia, September 16–17, 2004. Proceeding CD, p. 94–102.

[iki}, D. i drugi 1989: Tehni~ki uvjeti za gospodarske ceste, Znanstveni savjet za promet JAZU, Zagreb, 1–40. Sever, S., [unji}, S., 1996: Forest opening issues in Croatia. Proceedings of the „Seminar on Environmentally sound forest roads and wood transport«, Sinaia (Romania), June 17–22, 1996, p. 252–260.

Sa`etak

[umske prometnice u Republici Hrvatskoj – stanje i perspektiva [umska je prometna infrastruktura jedan od temeljnih preduvjeta kvalitetnoga gospodarenja {umskim ekosustavom. Unato~ dosada{njim zna~ajnim investicijama u ovom segmentu {umarstva, poglavito od osamostaljenja Republike Hrvatske, treba izgraditi puno kilometara {umskih prometnica do dostizanja optimalne otvorenosti. Cilj je istra`ivanja ra{~laniti situaciju u svezi sa {umskim prometnicama u Republici Hrvatskoj, prepoznati i jasno definirati uo~ene probleme prema fazama uspostave optimalne mre`e {umskih prometnica na terenu (planiranje, projektiranje, izgradnja s nadzorom i odr`avanje) te predlo`iti postupke za njihovo rje{avanje. Podru~je istra`ivanja zapravo su sve {ume i {umsko zemlji{te kojim gospodari poduze}e H[ u Republici Hrvatskoj (1 920 000 ha ili 80,2 %) preko svojih 16 U[P (slika 1). U tablici 1 donosi se postoje}a primarna otvorenost uprava {uma podru`nica (dalje U[P) koja je izra~unata kao prosje~na, iako se u ve}ini U[P nalazi kombinacija razli~itih reljefnih podru~ja. Ra{~lani li se postoje}a primarna otvorenost {uma kojima u Republici Hrvatskoj gospodari poduze}e H[ preko U[P, uo~avaju se velike razlike. Te su razlike, osim razli~itih stani{nih i sastojinskih prilika, uvjetovane i druga~ijim pristupom primarnomu otvaranju {uma razli~itim tehnikama i postupcima pridobivanja drva (ali i u pro{losti nejednakim financijskim mogu}nostima investiranja u primarnu {umsku prometnu infrastrukturu). Ra{~lamba bi se postoje}e primarne otvorenosti trebala iskazivati na razini pojedine gospodarske jedinice uz obvezan prikaz vrijednosti srednje udaljenosti privla~enja. Jo{ je bolje, umjesto klasi~ne primarne otvorenosti, odrediti relativnu primarnu otvorenost (prikazuje omjer otvorene i neotvorene {umske povr{ine za ciljanu srednju udaljenost privla~enja drva u postocima) koja je pokazatelj kakvo}e prostornoga razmje{taja [C. U tablici su 2 prikazani radovi na niskogradnji obavljeni u razdoblju 2004 – 2006. godine na razini poduze}a H[. Ukupna vrijednost svih radova na niskogradnji iznosi u prosjeku 134 000 000 kn svake godine (oko 6 % ukupnoga godi{njega prihoda H[), od ~ega poduze}e H[ preko polovice (51,46 %), ra~unaju}i prema vrijednosti radova, izvede vlastitim kapacitetima. Najvi{e se radova na niskogradnji, gledano po U[P, obavilo u U[P Gospi}, {to je i razumljivo; ova uprava {uma podru`nica ima slabu primarnu i sekundarnu otvorenost, a ve}inom se nalazi na zahtjevnim terenima sa stajali{ta otvaranja {uma i pridobivanja drva. Desetogodi{nji (2006 – 2015) plan izgradnje {umskih cesta nalazi se u tablici 3. Prema planu izgradnje [C u razdoblju 2006 – 2015. godi{nje se planira izgraditi oko 300 km novih [C (donji i gornji stroj) uz planirani godi{nji tro{ak gradnje oko 54 000 000 kn (izra~unat temeljem planske cijene). U razdoblju 2004 – 2006. u izvedbu

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je donjega i gornjega stroja [C ulo`eno prosje~no 75 000 000 kn godi{nje, a izvedena su prosje~no 272 km donjega stroja i 319 km gornjega stroja [C godi{nje. Razlika u cijeni uz pribli`no jednaku koli~inu novih [C godi{nje upu}uje na preniske planske cijene u odnosu na ostvarene tro{kove gradnje. Realno je o~ekivati ve}e godi{nje tro{kove izgradnje [C od planiranih. Ra{~lamba plana otvorenosti 2015. godine upu}uje na potrebu ve}ega obujma gradnje [C nego {to je planirano. Jedan od kriterija procjene optimalnosti postoje}e mre`e [P te planiranja daljnjega otvaranja {uma jest i tehni~ko-tehnolo{ki kriterij (Pentek i dr. 2004a). Potrebno je izraditi operativnu klasifikaciju terena na razini Hrvatske koja }e odgovoriti na pitanje koje su tehnike i postupci pridobivanja drva optimalni u odre|enim terenskim i sastojinskim uvjetima pa temeljem operativne klasifikacije terena optimizirati mre`u [P. Dana{nja kvaliteta postupaka planiranja [P, projektiranja [C, izgradnje i nadzora gradnje [C i TP te odr`avanja [C na puno je vi{oj razini nego {to je bila po~etkom devedesetih godina. Ipak su, detaljnom ra{~lambom svake od spomenutih faza uspostave optimalne {umske prometne infrastrukture na terenu, uo~eni odre|eni problemi, nedostaci, manjkavosti i nepravilnosti. Za unapre|ivanje planiranja {umskih cesta potrebno je pridr`avati se ovih mjera i postupaka: Þ Nu`no je zakonski propisati obvezu izrade Studije primarnoga otvaranja {uma te Studije sekundarnoga otvaranja {uma. Navedene bi studije otvaranja {uma trebale biti sastavni dio programa gospodarenja, a izra|ivale bi se za razdoblje od 10 (20) godina. Þ Studiju primarnoga otvaranja {uma i Studiju sekundarnoga otvaranja {uma trebaju izra|ivati ovla{teni in`enjeri {umarstva – ~lanovi Hrvatske komore in`enjera {umarstva i drvne tehnologije, koji su jedini stru~ni i osposobljeni za taj posao. Þ U izradu je studija otvaranja {uma potrebno uklju~iti sve fizi~ke i pravne osobe (privatni {umovlasnici, jedinice lokalne uprave i samouprave, nadle`na ministarstva i institucije) kojima je u interesu sudjelovati pri dono{enju odre|enih odluka u {umarstvu. Ako se `eli unaprijediti projektiranje [C, potrebne su ove aktivnosti: Þ Þ Þ Þ

Nu`no je u {to skorije vrijeme izraditi nove Tehni~ke uvjete za {umske prometnice. Prioritet je i izrada Priru~nika za projektiranje {umskih cesta. Treba dizajnirati novi ra~unalni program za projektiranje [C. Potrebno je ustrojiti stru~no, kvalificirano Povjerenstvo za reviziju izra|enih projekata [C, ~ime bi se prije ulaska u izgradnju osigurala vjerodostojnost i kakvo}a tehni~ke dokumentacije. Þ Treba razmisliti o izradi glavnih projekata TP jer su oni, kao i [C, gra|evinski objekt trajnoga karaktera u {umi. Kao preporu~ene mjere i postupke pobolj{anja postoje}e situacije u svezi s izgradnjom [C i TP te nadzora gradnje navodi se sljede}e: Þ Preko [umarske komore, a unutar stru~noga smjera [umske prometnice i {umarsko graditeljstvo treba zapo~eti s postupkom licenciranja radova i izvoditelja radova povezanih sa {umskim prometnicama. Þ Izvo|a~i izgradnje, odr`avanje i popravaka {umskih prometnica trebaju se organizirati i ustrojiti svoje strukovno udru`enje koje }e {tititi njihove interese. Þ Stalna prisutnost voditelja gradili{ta, kojega imenuje izvoditelj radova, na gradili{tu (u slu~aju izostanka voditelja gradili{ta nadzorni in`enjer treba obustaviti izgradnju). Þ Stalna prisutnost nadzornoga in`enjera na gradili{tu uz kontrolu radova i usporedbu s glavnim projektom te pra}enje Gra|evinske knjige i Gra|evinskoga dnevnika. Trebalo bi, radi unapre|ivanja radova na odr`avanju [C, uzeti u obzir navedene mjere i postupke: Þ U okviru je Tehni~kih uvjeta za {umske prometnice, u poglavlju Odr`avanje [C, nu`no definirati obujam radova na stalnom odr`avanju te u~estalost i intenzitet radova na periodi~nom odr`avanju [C sukladno novoj kategorizaciji [C. Þ Razvijanje metodologije prikupljanja uzoraka na razini gospodarske jedinice kojima }e se brzo i dovoljno to~no dobiti pregled stanje kakvo}e postoje}e mre`e [C. Þ Unutar Studije primarnoga otvaranja {uma treba napraviti godi{nje planove odr`avanja mre`e [C u pojedinoj gospodarskoj jedinici. Þ Izrada elaborata odr`avanja pojedine [C poglavito onih koje zahtijevaju ve}e intervencije.

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Osnovni, u prvom redu zakonski i organizacijski preduvjeti koji su u ranijim raspravama o pobolj{anju postupaka otvaranja {uma odre|eni kao klju~ni, ostvareni su. Tu mislimo na osnivanje Hrvatske komore in`enjera {umarstva i drvne tehnologije i unutar nje zasebnoga stru~noga smjera [umske prometnice i {umarsko graditeljstvo. Time su stvoreni okviri u kojima se treba zalagati za pozicioniranje ovoga segmenta {umarstva unutar {umarske struke, a i izvan nje. Postavljeni su temelji koji pru`aju dobre mogu}nosti razvoja, ali treba biti svjestan kako }e kona~an rezultat ovisiti ponajvi{e o nama samima. Klju~ne rije~i: {umske prometnice, planiranje, projektiranje, izgradnja, odr`avanje, tro{kovi, Hrvatska

Authors’ address – Adresa autorâ:

Received (Primljeno): December 8, 2006 Accepted (Prihva}eno): March 8, 2007

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Asst. Prof. Tibor Pentek, PhD. e-mail: pentek@sumfak.hr Hrvoje Neve~erel, BSc. e-mail: hnevecerel@sumfak.hr Asst. Prof. Dragutin Pi~man, PhD. e-mail: picman@sumfak.hr Asst. Prof. Tomislav Por{insky, PhD. e-mail: porsinsky@sumfak.hr Forestry Faculty of Zagreb University Department of Forest Engineering Sveto{imunska 25 HR-10 000 Zagreb CROATIA Croatian Journal of Forest Engineering 28(2007)1


Subject review – Pregledni ~lanak

Forest operations engineering and management – the ways behind and ahead of a scientific discipline Hans Rudolf Heinimann Abstract – Nacrtak The forest operations engineering and management community has been facing the problem of improving its scientific visibility, realigning its research efforts to the future challenges, and of strengthening its self-confidence. The paper aims at exploring the paradigms that shaped the development of forest operations as a scientific discipline, sketching a vision how forest operations could look like in 2020, establishing a common understanding for future of the discipline, and discussing the major challenges ahead. The investigation identified five periods of steady state development (paradigms) and developed a vision of network-based forest operations systems, built of »self-organizing« cells. It then discusses the challenges that we will probably been faced with in the fields of »harvesting and transportation engineering«, »forest operations management«, »forest ergonomics«, and »forest operations ecology«. The study intended to trigger a broad discussion on the future directions of forest operations engineering and management, and to build a basis for a redesign of corresponding curricula in higher education.

Keywords: forest operations, forest engineering, paradigms, future challenges, scientific discipline, historical development

1. Introduction – Uvod Forest operations has been the prevailing term to characterize a scientific discipline, which addresses design, implementation, control, and continuous improvement of forest operations systems. The value of a problem-oriented discipline depends on its recognition within the family of scientific communities, and on its capability to provide solutions to emerging problems. In the last 10 years, we have been facing fundamental economic, social and environmental changes that can be characterized by trends, see for example (Davis and Stephenson 2006). Forest operations as technology-based discipline is both technology, and problem driven. Information, WWW, and sensor technology have had a big influence on our field of interest. On the other hand, the problems of global change, increasing demand for resources, or the critical attitude of society towards technology have been shaping the development as well. In our point of view, the voice of the forest operations community has been weak or has Croatian Journal of Forest Engineering 28(2007)1

even fallen silent, resulting in decreasing funding and recognition. The International Union of Forest Research Organization IUFRO has undertaken a major effort (1) to strengthen research, (2) to expand strategic partnership and cooperation, (3) to enhance the commutation with the scientific community, and (4) to improve the commutation with policy makers. Such a development should be driven by future challenges, and be based on a common understanding what the fundamentals of the corresponding scientific discipline are. Previous papers on forest operations as a scientific discipline covered the periods from the 1970s to the 1990s (Heinimann 1995, Samset 1992, Sundberg 1988). The present paper aims at (1) exploring the conceptual worldviews (paradigms) that shaped the development of forest operations as a scientific discipline, (2) sketching a vision how forest operations could look like in 2020, (3) establishing a common understanding for the future of our discipline, and (4) discussing the major challenges that we will probably been faced with. The scope of the paper is

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somewhat limited by the perceptions, expectations and values of the author, which will influence the ideas on future developments. It is also shaped by the »western« perspective that probably neglects to developments in other cultural areas. The paper will first describe five paradigmatic phases of development, next sketch a 2020 vision of forest operations system as network-systems of self-organized cells, then proposes a definition of forest operations engineering and management as a scientific discipline, and finally sketch the challenges for harvesting and transportation engineering, forest operations management, forest ergonomics, and forest operations ecology.

2. The Way Behind – Osvrt unazad 2.1 The Phenomenon of Discontinuous Evolution – Fenomen diskontinuirane evolucije Scientific disciplines have been continuously evolving, similar to biological systems. Understanding possible paths of future development requires a basic understanding of how systems change over time. In biology, evolution has been understood as a »slow stream of mutations«, that gradually results in novel forms of organisms and systems (Gersick 1991). However, a new theory of »discontinuous evolution« has been challenging the concept of continuous, gradual change (Gould and Eldredge 1993). It is based on the assumption that systems exist for most of their history in a series of consecutive, steady state levels that are connected by sudden, non-linear »punctuations« of discontinuous change. Relatively long periods of stability are punctuated by compact periods of qualitative, metamorphic changes. This concept of punctuated equilibrium can be found in several areas of science, e.g. in biology (Gould and Eldredge 1993), in philosophy of science (Kuhn 1970), organizational theory (Gersick 1991), or software development (Aoyama 2002, Wu et al. 2004). Thomas Kuhn (Kuhn 1970) accordingly provided a model of »punctuated equilibrium« for scientific disciplines, for which he called steady state periods as »normal science«, and periods of discontinuous change as »scientific revolutions«. He introduced the term »paradigm« to characterize a specific steady state period of »normal science«. Ivar Samset, one of the leading forest operations scholars of the 1950s and 1960s was the first to describe the phenomenon of »discontinuous evolution« related to forest operations (Samset 1966). Although he did not identify patterns of discontinuous evolution for our scientific discipline as a whole, he presented findings for

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punctuated discontinuity for the evolution of Norwegian cable systems. Previous studies of the author (Heinimann 1995, Heinimann 1997) indicated that similar evolutionary patterns may be found for the whole domain of forest operations engineering and management. However, we are far away from fully understanding the emergence and the development of our field of interest, because there is not only variation in time but also variation in space that results in different paths of development in different areas of the world.

2.2 Paradigmatic Patterns of Evolution – Paradigmatski uzorci evolucije Following Kuhn (Kuhn 1970), paradigms are conceptual world-views that (1) define scientific thought (basic assumptions), (2) determine the problems to be important, and (3) shape the type of questions to be investigated. Paradigm shifts (1) alter the fundamental concepts underlying research, (2) inspire new pathways of theory and experiment, (3) encourage new research techniques, and (4) promote new standards of evidence. The question to be asked is if those alternating patterns of relative stability and drastic changes can be observed in our field of interest, forest operations engineering and management, as well. Our investigation is based on the assumption that the »big picture« of evolution of forest operations engineering and management may be characterized by two main dimensions: (1) scientific theories and procedures (x-axis in Fig. 1), and (2) the observed and scrutinized level of complexity of the study objects (y-axis in Fig. 1). The level of complexity follows the »skeleton of science« as proposed by Boulding (Boulding 1956).The first dimension, scientific theories and procedures, can be described by a consecutive sequence of scientific procedures. The second dimension, the level of complexity, by a distinct set of complexitiy levels, ranging from a simple, static framework to self-adapting, autonomous systems (Fig. 1). The five steady state periods of evolution (Fig. 1) will below be described in more detail. 2.2.1 Utilization paradigm – Paradigma kori{tenja The emergence of organized records of forest operations knowledge goes back to the 17th century when engineering knowledge was recorded systematically by proponents of mercantilism in France. The textbooks published by Duhamel du Monceau, a high-ranked French civil-servant, is – according to our knowledge – the cradle of forest operations engineering and management in the modern scientific world. The first title of a trilogy, »The art of making Croatian Journal of Forest Engineering 28(2007)1


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Fig. 1 Patterns of evolution characterizing the evolution forest operations engineering and management as a scientific discipline Slika 1. Uzorci evolucije koji opisuju evoluciju {umarskoga in`enjerstva i upravljanja {umskim radovima kao znanstvenu disciplinu

charcoal« (Duhamel du Monceau 1761), was followed by »Forest utilization – with a description of the art of forest practices« (Duhamel du Monceau 1764), and finished by »About timber transportation, conservation, and material strength, with an emphasis on ship building« (Duhamel du Monceau 1767). The texts clearly indicate the rationale, providing the timber required for the fortifications of the French army, and the timber required building war ships for the French Marine. We characterize this first phase of development as »utilization paradigm« because it was mainly motivated by the increasing demand of timber for government use. The accurate description of structural aspects is the beginning of organized theoretical knowledge in almost any field (Boulding 1956). In our field of interest it is mainly a systematic survey of tacit knowledge embodied by practices that evolved form trial and error and defined by rules of thumb. 2.2.2 Tayloristic Paradigm – Taylorova paradigma The emergence of industrial engineering as a scientific discipline at the beginning of the 20th century induced (1) the systematic study of work processes Croatian Journal of Forest Engineering 28(2007)1

by time studies, and (2) the development of formal training based on the assumption that there is one »single best practice« that can be derived by scientific investigation of work elements and by systematically rearranging them by using performance metrics. There are hints that Vauban – the well-known French fortification specialist – was probably the first to do work studies (Hilf 1926), which would become a guiding methodology 150 years later when Fredric Taylor’s seminal texts on time studies and piece-rate systems (Taylor 1895), on shop management (Taylor 1903), and on scientific management (Taylor 1911) triggered a punctuated discontinuity of development. We call this second phase of development »Tayloristic Paradigm« because it changed the conceptual world view on labor into a mechanistic clockwork system that could be designed and controlled deterministically. It also had a decisive effect on the philosophy of worker training. For centuries, personal observation was the mean to acquire skills and competences. Taylor’s concept of time studies got into forestry at about 1910 (Braniff 1912) and resulted in the first formal description of the »piece-

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volume-law« that expresses the principle that time consumption per unit of volume decreases with increasing volume per work piece (Ashe 1916, Strehlke 1927). The new paradigm, that Hilf (Hilf 1926) described »Die Zahl herrscht – Das Gefühl muss schweigen« [Numbers are ruling – the feeling has to be silent«; translated by the author] initiated the establishment of scientific groups dedicated to the study of forest work. The Institute of Forest Work Science (Hugo H. Hilf, Germany), founded in 1927, should become a nucleus for the emergence of forest work science. In 1927, Alexander Koroleff started his work at the Woodlands Section of the Canadian Pulp and Paper Association CPPA (Sundberg 1988), resulting in a series of green covered texts dealing with pulpwood cutting, skidding, hauling, driving, road construction and forest management, which set a standard, worldwide, for work in this field (Sundberg 1988). Roughly in 1912 the United States Forest Service established a Logging Engineering Division within the Office of Silviculture (Girard 1917), out of which came a number of pioneering studies (Ashe 1916, Girard 1917, Girard 1922). However, manual work and horse logging were dominating through the »Tayloristic Paradigm« period (Koroleff 1952), and the Second World War stopped mechanization efforts and even lead to serious reversals. 2.2.3 Mechanization Paradigm – Paradigma mehanizacije During the Second World War important new theories were developed to solve pressing engineering problems (Sheridan 1985). Off-Road-Locomotion was one of the decisive problem drivers that triggered mechanization of forest operations after Second World War. This third period of development (Fig. 1), starting around the 1950s, was dominated by the »Mechanization Paradigm«, because research efforts aimed at substituting the production factor »work« by the production factor »capital«. The awareness for logging mechanization spread, mainly from the USA and Canada, to Europe and the USSR at the end of the reconstruction period of 19231927 (Koroleff 1952). However, major progress occurred when government efforts were made after Second World War in the USA (Forest Service Technology and Development (formerly Equipment Development and Testing) Program), the USSR (Central Research Institute of Logging Mechanization and Power Sources in the Forest Industry ZNIIME (Koroleff 1952), and Canada (Mechanization Steering Committee of CPPA Woodlands Section in 1948 (MacDonald and Clow 2003)) to promote the development of logging machinery. These efforts resulted in three types of new machinery that should trigger a

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kind of revolution of logging practices: (1) the power saw, (2) the skidder, and (3) the truck for on-road transportation. In parallel, governments built laboratories to study the body measures and the physiological performance of populations that would be machine operators (mainly pilots, sailors, soldiers), resulting in the establishment of a new scientific discipline, known as »human factors engineering« in the USA, or »ergonomics« in the UK (Sheridan 1985). Additionally, methods of mathematical statistics, originally developed by R.A. Fisher (Fisher 1925, Fisher 1935) entered the field of forest operations, changing both experimental design and data analysis (Steinlin 1987). The years from 1950 to 1970 were the period of greatest activity in the development of mechanization. They led to a series of outcomes that were essential for the consolidation of forest operations as a scientific discipline. First, the establishment of an invisible college could be observed (Silversides 1988). An invisible college refers to a small group of researchers that regularly exchange information about the newest progress on the research front, and that maintain personal relationships. The most important scholars of this invisible college were: Ivar Samset, Norway; Ulf Sundberg, Sweden; Hansjürg Steinlin, Switzerland/Germany, Kalle Putkisto, Finland; C. Ross Silversides, Canada; Louis-Jean Luissier, Canada; Tom Walbridge, USA; Peter Koch, USA; Konstantin S. Voronitsin, U.S.S.R.; Ivan Klemen~i}, Yugoslavia; and others (Sundberg 1988). Second, a formal structure for the international exchange of scientific information established when the International Union of Forest Research Organizations, IUFRO, implemented a new organizational structure at the world Congress of 1948 (Zürich, Switzerland), consisting of 11 sections, one of which was section 32 »operational efficiency«. The section leaders were: G. Luthman (Sweden, 1949), G. Callin (Sweden, 1950), U. Sundberg (Sweden 1951–1961), I. Samset (Norway, 1962–1967). B. Ager (Sweden, 1968–1971). Third, a number of university professorships were created and filled (Sundberg 1988). In 1949, the Royal College of forestry, Sweden, implemented a professorship on operational efficiency that was headed from 1949 to 1951 by G. Luthman and from 1952 to 1985 by U. Sundberg. Similar professorships were formed in Germany in 1955 (Göttingen, Gläser) and in 1958 (Freiburg, H. Steinlin). In 1956 Ivar Samset started office in As, Norway, and in 1963 the University of New Brunswick filled similar positions with L. Seheult and T. Bjerkelund. The influence of the mechanization period has still been ongoing. There are still several professorships named »forest mechanization«, especially in Eastern and Southern Europe. Croatian Journal of Forest Engineering 28(2007)1


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Table 1. Systems-oriented analytical approaches to advice decision- and policy-makers, following (Quade 1968a) Tablica 1. Analiti~ki pristupi orijentirani prema sustavu za savjetovanje donositelja odluke i kreatora politike (Quade 1968a)

2.2.4 Systems Paradigm – Paradigma sustavâ The development of a variety of machines led to an exponentially increasing complexity due to the increase of options for a specific operation. Additionally, some of the thinkable concepts were so novel that their exploitation could not be poorly planned on the basis of traditional experience. There was a lack of approach to evaluate the best sequence of harvesting, processing, transportation, and materials handling processes (Silversides 1988). Similar types of problems occurred in military technology during the second world war, and triggered the development of new theories to solve pressing engineering problems (Sheridan 1985). Nowadays, this area of knowledge is known as systems theory, covering several scientific fields, such as systems engineering, systems analysis, and theory of control. The first attempts to follow a systems approach to solve operational problems in forestry goes back to the 1950s (Silversides 1988). However, serious application of systems theory entered forest operations only at the beginning of the 1970s (Hopper 1973). We characterize this fourth phase of development as »systems paradigm«, because it totally changed the way of thinking and lead to a set of highly-mechanized harvesting systems that have been dominant for many years. The essence of the systems approach is to identify or recommend a course of action or a set of actions Croatian Journal of Forest Engineering 28(2007)1

that best fit with a set of objectives. It aims at »using an appropriate framework – in so far as possible analytic – to bring expert judgment and intuition to bear on the problem« (Quade 1968b), what could be seen as »mechanization of brainwork«. Quade (Quade 1968a) presented a framework to classify and characterize the type of problems to be tackled by systems analysis (table 1). Management of operations, the first level of analysis, aims at increasing the efficiency of man-machine systems in a certain context. This type of problem is usually of low complexity and high structuredness. The second level of analysis aims at choosing courses of actions out of a set of alternatives that maximize some effectiveness-cost measures. The third level of analysis addresses the design and control of new systems to improve existing operations or to implement operations that were never performed before. The fourth level of analysis, strategy or policy analysis, aims at investigating a portfolio of future activities and at identifying the means to achieve them. The fourth level of analysis is characterized by high complexity and low structuredness. Quade’s framework (table 1) is continuing to be useful. During the 1960s, a Swedish group at Skogsarbeten [Swedish Logging Research Foundation] explored an approach based on systems theory (Hedbring and Åkesson 1966, Hedbring et al. 1968) aiming at developing novel harvesting systems that followed

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the vision »no man on the ground, no hand on the wood« (Lundell 2003). Researchers of the Logging Development Program of the Canadian Forest Service adapted the Swedish report to North American conditions (McCraw and Silversides 1970). Systems engineering is an interdisciplinary process to transform needs, requirements, and constraints into a system solution throughout the systems lifecycle (IEEE 1998). The systems engineering process tackles a design problem by stepwise refinements, going top-down through three phases: (1) system definition, (2) preliminary design, and (3) detailed design. The functional architecture is the main outcome of the systems definition phase (IEEE 1998), describing the (1) arrangement and (2) sequencing of system functions. The Swedish study identified five processing functions (fell, delimb, buck, debark, chip) that could be allocated to four processing locations (stand, strip trail, truck road, landing). Considering, that the felling process has to occur in the stand there are 256 possibilities to allocate processing functions to processing locations. 26 of them were selected for further investigation, while 15 were used for detailed analysis (Hedbring et al. 1968). The next step of the systems engineering process had to group functions that are allocated to machine concepts. The study identified 14 mobile processing and three off-road transportation machine concepts that built the framework for productivity and cost analysis. This Skogsarbeten study (Hedbring et al. 1968) had far-reaching impacts. First, it defined the classes of harvesting systems (cut to length, tree length, full tree) and the corresponding types of harvesting machines (for example feller-buncher, feller-delimber-bucker [nowadays known as harvester], delimber-bucker [known as processor], etc.) that are still in use today. Second, it identified a full-mechanized cut-to-length harvesting system consisting of a harvester and forwarder that has been decisive for mechanized harvesting operations in many countries of the world. Systems analysis in a broader sense (table 1) provides analytical tools and methods for the design and control of new systems to implement operations that were never performed before (Quade 1968b). Simulation of harvesting systems first emerged within the logging development program of the Canadian Forest Service under the leadership of C. Ross Silversides (MacDonald and Clow 2003, Silversides 1988). The rational for the simulation studies was to evaluate the functional requirements and the corresponding trade-offs for a range of operational scenarios (Newnham 1967b). Simulated testing has many advantages over field testing (Newnham 1967b). First, the method is very rapid. Second, it is possible

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to vary machine parameters without the expense of modifying a real machine. Third, machines can be tested in a wide range of stand conditions using data from either actual or hypothetical stands. Fourth, several tests may be made in the same stand, thus eliminating the »between stand« variation. Fifth, it makes it possible to study the effect of varying one stand or machine parameter while keeping the remaining characteristics constant. The main efforts to simulate novel machine concepts took place between 1966 and 1971. The first simulation model was very simple and restricted to two machine types (Newnham 1966). It was continuously revised and improved (Newnham 1967a, b) and resulted, in cooperation with the Royal College of Forestry, Sweden, and the Swedish Logging Research Foundation, in the so-called Newnham-Sjunnesson model (Newnham 1970, Newnham and Sjunnesson 1969). The model was later adapted to consider the prevailing requirements of North American conditions, harvesting larger trees mainly in clear felling operations. The resulting model, CANLOG (Newnham 1971), has been used extensively by one major Canadian manufacturer to test several machine concepts and to select the specifications for the detailed design. However, those simulation models could not be used for comparing machines from different harvesting systems, nor could it be used to see how a new machine concept might fit into existing harvesting systems. Systems analysis in a more narrow sense, often called operations research, aims at increasing efficiency of man-machine systems in a certain context (table 1). Harvesting researchers realized that increasing mechanization by itself is not sufficient to improve stand to mill operations (Newnham 1973). Therefore, increased emphasis was placed on planning, scheduling and control of harvesting and transportation operations (Newnham 1973). Although technof systems analysis were used as early as 1955 to improve harvesting operations, they were limited and generally did not account for the interactions of topography, timber size, timber distribution, personnel, and machinery (Bare et al. 1984). Increasing computing power and the availability of more sophisticated methods resulted in a takeoff of operations research methods related to forest operations. In 1976, two seminal contributions were published. Dykstra was the first who simultaneously optimized the spatial layout of cutting units and the selection of harvesting systems (Dykstra 1976, Dykstra and Riggs 1977). At the same time Weintraub concurrently solved the optimization of timber management activities, road construction activities and transportation activities with a mixed-integer approach (Weintraub and Navon 1976). Dykstra and Weintraub were the Croatian Journal of Forest Engineering 28(2007)1


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door openers to a huge opportunity-space offered by the methods of operations research. Subsequently, a new research stream emerged, resulting in a forest operations specific body of knowledge (Church et al. 1998, Martell et al. 1998, Weintraub and Bare 1996). 2.2.5 Network Paradigm – Paradigma mre`e The traditional view consisted of a dichotom characteristics of human and artificial systems (BernersLee 1998). Whereas artificial systems have been seen as working purely mechanically, it was clear that humans have the capabilities to solve ill-structured, complex problems by using heuristics and intuition. The design of socio-technical systems was therefore done with static allocation of functions, what means that the division of tasks between humans and machines was fixed by the designer (Lee 2001). The increasing allocation of tasks to machines and systems lead therefore to an increasing degree of static relationships between the systems components, resulting in a loss of flexibility, expandability and adaptability to changing manufacturing environments. Centralized, hierarchical systems with static interactions often lead to situations where the whole system shut down by a single failure at one point (Colombo et al. 2006). One promising structure to overcome this problem is to have a conglomerate of distributed, autonomous, intelligent, fault tolerant, and re-usable processing units, which operate as a set of cooperating entities (Colombo et al. 2006). The World Wide Web technology provided the possibility to store random associations between disparate things (Berners-Lee 1998). The dream behind the Web was to create a common information space in which we communicate by sharing information that would be so generally used that it became a realistic mirror of the ways in which we work, play and socialize (Berners-Lee 1998). Internet technology should become the key technology driver to allocate tasks dynamically, meaning that the division of tasks between humans and systems only depends on the moment to moment allocation. Dynamic function allocation requires a new description of the interaction between systems and humans because swarms of agents are adapting to the environment in unpredictable ways. This could even lead to the characteristic behavior of complex, adaptive systems, characterized by self-organization and emergence of new properties (Colombo et al. 2006). We call this fifth, ongoing phase of development »network paradigm« (Moridera et al. 2000). It will transform the way people live and interact, although we are at an early, not mature, stage of this new paradigm (Davis and Stephenson 2006). Croatian Journal of Forest Engineering 28(2007)1

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The network paradigm is characterized by dynamic allocation of functions to cells and links between cells. Therefore, it opens new ways of cooperation and interaction between humans, and complex »man-made« systems. However, the change of technology is much faster than the change of management structures, what is called »second generation management applied to fifth-generation technology« (Savage 1990). This mismatch of technology and management often resulted in failures of new approaches. A novel approach, called business process reengineering, aims at closing this gap by concurrently re-designing and controlling technical and administrative processes. Porter’s seminal work on the value chain (Porter 1985) identified nine primary activities, (1) inbound logistics, (2) operations, (3) outbound logistics, (4) marketing and sales, (5) service, and for supporting activities, (6) procurement, (7) technology development, (8) human resource management, (9) firm infrastructure, that should dramatically change our way of thinking about manufacturing and operations. Porter’s work probably triggered the establishment of »chain«-disciplines, such as logistics and supply chain management. Those »chain«disciplines entered into the forest operations community with some phase difference by the end of the 1990s (Heinimann 1999), and became a subject of discussion after the 1st World Symposium on Logistics in the Forest Sector (Sjöström 2000), held in 2000 in Helsinki, Finland.

3. The Way Ahead – Put naprijed Following the previous thoughts, we have been entering a phase of development that we characterize by the »network paradigm«. This raises the question where we will be heading? Below, we will discuss some challenges that we will probably been facing. The identification of the challenges is based on two pillars: (1) trends documented in the scientific literature, and (2) the personal experience of the author as a coordinator of the division »forest operations engineering and management« of the International Union of Forest Research Organizations IUFRO. Below, we will first sketch a possible vision, how operations systems could look like in 2020, next propose a definition of our scientific discipline, and then discuss some challenges in four areas of activity: (1) harvesting and transportation engineering, (2) forest operations management, (3) forest ergonomics, and (4) forest operations ecology. We are aware, that the discussion of future trends will always be biased by the perceptions, values and expectations of the author.

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3.1 2020 Vision – Vizija 2020. In 2020 forest operations system will be networksystems of self-organized »cells« [holons] that Þ are autonomous, cooperative building blocks for transforming, transporting, storing, and/or validating physical objects and information; Þ have some machine intelligence to control actions autonomously and to negotiate and cooperate with other entities [distributed, coordinated decision-making] Þ consist of (1) an information processing part (software) and (2) a physical processing part (hardware). Several emerging concepts that advocate intelligent and distributed manufacturing structures have been reported in the literature. A new generation of manufacturing systems is referenced as holonic manufacturing systems and is characterized by a set of distributed, autonomous, intelligent units that have the capability to negotiate, to cooperate, and to selforganize (BMED 1998, Colombo et al. 2006). The word »holon« describes the hybrid nature of the whole and its parts. Holons are »sufficiently autonomous self-reliant units that have a degree of independence and handle situations without asking higher authorities for support« (Colombo et al. 2006). Accordingly, our scientific discipline, forest operations engineering and management, can be defined as follows1: Forest operations engineering and management research aims at (1) understanding the fundamental principles that underlie the behavior of forest operations systems and at (2) developing concepts, methods and tools that support the design, the implementation, the operation, and the continuous improvement of these systems. It is problem-oriented, aiming to provide designs, plans, schedules, and control mechanisms that are: Þ bio-physically effective, considering the physical laws, engineering principles, and environmental relationships of forest ecosystems, Þ economically efficient, considering the costs and benefits of short and long range consequences, Þ individually compatible, considering to prevent adverse health effects, prevent adverse effects on the psychosocial well-being, foster the

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development of personal skills and attitudes, and promote social reasonability, Þ environmentally sound, considering impacts on the natural and social environment and efficient use of resources including non-renewable materials, renewable materials, water, energy, and space, Þ institutionally acceptable considering laws, regulations, and informal rules governing the forest operation, landowner objectives, and social values. The underlying research paradigm represents operations systems as flow networks and uses mathematical models to describe its behavior and to evaluate the efficiency, effectiveness and environmental performance of alternate policies, strategies, and practices. The operations core is a system that includes research, design, engineering, production within operating units, networks of information and material flows that tie operating units together, and the development, distribution and delivery of goods and services to customers. Forest operations engineering and management has always been borrowing concepts and models from »umbrella«-disciplines, such as industrial engineering, operations management, ergonomics, or industrial ecology. We have to be interested in maintaining the inspiring influence of »mother« and »neighboring« disciplines, and in demonstrating that we have strong links to those »umbrella«-disciplines. This is why the International Union of Forest Research Organizations renamed the field of research from »Forest Operations« to »Forest Operations Engineering and Management«.

3.2 Challenges in Harvesting and Transportation Engineering – Izazovi u in`enjerstvu pridobivanja i prijevoza drva Harvesting and transportation engineering consists of analysis, design and continuous improvement of the facilities and networks of technical and transaction processes required to harvest and to transport biomass and/or non-wood products from the stump site to mill facilities. The corresponding clusters of primary processes are (1) tree conversion, (2) off-road transportation, (3) material handling, and (4) on-road transportation. Classes of transaction processes are (5) procurement, (6) order fulfillment,

This definition is a further development of former work (Heinimann 1995, Sundberg 1988, Samset 1992). The author is also grateful to John Sessions and John Garland, Oregon State University, for the valuable discussions that led to the present understanding. – Ova je definicija nastavak razvoja prija{njega rada (Heinimann 1995, Sundberg 1988, Samset 1992). Autor zahvaljuje Johnu Sessionsu i Johnu Garlandu na dragocjenim razgovorima koji su doveli do dana{njega razumijevanja.

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(7) data exchange, and (8) system monitoring and control. The publication »Visionary manufacturing challenges for 2020« (BMED 1998) identified six grand challenges, three of which are relevant for harvesting and transportation engineering. Those are: Þ to achieve concurrency in all operations, Þ to reconfigure manufacturing enterprises rapidly in response to changing needs and opportunities, and Þ to develop innovative manufacturing processes with a focus on decreasing dimensional scale. The first challenge, concurrency, addresses the problem of distributed systems engineering (including sensor networks, pervasive computing systems, and peer-to-peer systems) (Zambonelli and Rana 2005). The second challenge is related to the increasing need for flexibility. The third challenge, tackling decreasing dimensional scale, is also relevant for forestry. It does not mean the dimension of a work piece, but mainly the dimension of the smallest discrete spatial unit to be managed. The ultimate unit will be the individual tree. In our point of view, harvesting and transportation engineering will be facing the following challenges: Þ to develop and/or deploy flexible sensors and control algorithms that provide precision process control in both time and space [sensor technology as a driver], Þ to develop and deploy autonomous harvesting and transportation cells that have some control, negotiation, and cooperation intelligence CNCI [«cell« intelligence as a problem driver], Þ to disseminate and apply the knowledge on environmentally sound harvesting technologies to developing countries (especially in the tropics) [transfer of environmentally sound technology as a problem driver], Þ to disseminate and apply the knowledge on industrialized, highly-mechanized harvesting technologies to countries in transition [transfer of harvesting system technology as a problem driver].

3.3 Challenges in Forest Operations Management – Izazovi u upravljanju {umskim radovima Forest operations management consists of analysis, design, control, and continuous improvement of

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business processes, such as procurement, order fulfillment, distribution, monitoring and control within firms and business to business (B2B) networks. It measures and analyses internal processes with emphasis on effectiveness, efficiency, and quality by using quantitative models to map and solve related problems of scheduling, inventory, shipment routing, or facility location. The publication »Visionary manufacturing challenges for 2020« (BMED 1998) identified six grand challenges, one of which is relevant for forest operations management: to instantaneously transform information gathered from a vast array of sources into useful knowledge for making decision. In our point of view, forest operations management will be facing the following challenges: Þ To move from business management to supply chain management through reengineering business processes (Heinimann 2000, Loch 1998), by (1) adapting standard supply chain operations reference models (e.g. SCOR (Huan et al. 2004)), and by (2) tailoring and implementing business to business (B2B) transaction standards (e,g, -WoodX-XML, StanForD-XML), Þ To develop mathematical tools (1) to support distributed, coordinated decision making (e.g. agent-based modeling techniques), (2) to identify near-optimal solutions for complex geographical problem spaces with intelligent search techniques (e.g. genetic algorithms, simulated annealing, etc.), and (3) to link optimization models to on-the-ground conditions by making them spatially explicit. Þ To close the substantial gaps between supply chain management theory and practice (Storey et al. 2006) by (1) integrating the body of knowledge into curricula and into mental models of both researchers and practitioners, and by (2) modeling supply networks with generic, static or dynamic process models2 (Harrison 2002). In our point of view »supply chain management« has often been used as a buzzword to wrap up »old wine in new bottles«.

3.4 Challenges in Forest Ergonomics – Izazovi u ergonomiji {umarstva Forest Ergonomics is the area of knowledge dealing with the capabilities and limitations of human performance in relation to design of forest machines,

A process network is modeled as a mathematical graph in which flows (resources, goods, services) traverse edges, and whose nodes represent activities that transform the flows. – Mre`a je procesa modelirana kao matemati~ki grafikon u kojem se vrijednosti veli~ina (sredstva, proizvodi, usluge) presijecaju, a presjeci{ta predstavljaju aktivnosti pri kojima se veli~ina transformira.

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jobs, and modifications of the physical environment. It seeks to ensure that human’s tools, machines, and work systems are best matched to their (1) physical strength, size, and speed and to the capabilities of (2) sense, (3) memory, (4) cognitive skills, and (5) psychomotor preferences. The field of knowledge is also termed human-factors engineering, or human engineering. The ultimate goal of ergonomics has been to create humane working conditions. It is similar to engineering in that it is heavily designed oriented (Brewer and Hsiang 2002). Humane working conditions have to (1) prevent adverse health effects, (2) prevent adverse effects on the psychosocial well-being, (3) foster the development of personal skills and attitudes, and (4) promote social reasonability (Ulich 1992). Since the nature of work is not stable, but changes with the developments in technology and society, the contents of ergonomics must also change (Hollnagel 2001). Three streams of ergonomics may be identified: (1) »classical economics«, tackling with body-work compatibility, (2) »cognitive ergonomics«, aiming to improve mind-work compatibility, and (3) »control ergonomics«, investigating system-goal compatibility (Hollnagel 2001). Classical ergonomics has been existing for about 60 years (Sheridan 1985), resulting in a considerable body of knowledge. Compared to manufacturing industries, the forest sector still has a lot of workplaces at which muscular work has been dominating. This is especially true for developing countries and for countries in transition. Countries with a highly industrialized forest sector, such as is the Nordic countries, mainly provide workplaces at which cognitive work has become dominating, and which are increasingly influenced by computerization (e.g. harvester-operator workplace). In our point of view, forest ergonomics will be facing the following challenges: Þ To disseminate the knowledge of classical ergonomics to developing countries and to implement and enforce working standards adapted to location-specific, often harsh working conditions and to biomechanical and physiological characteristics of the workers. Þ To improve the human-software interface to empower people and to leverage cognitive, perceptual, and collaborative skills (Hoffman et al. 2002). Þ To overcome the problem of »2nd generation management applied to 5th generation technology (Brewer and Hsiang 2002) by macroergonomic redesign of the human-organization interface (Hendrick 2002, Kleiner 2002, 2004, 2006).

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Þ To tackle the problem of socially distributed cognition and cooperation, resulting from the introduction of distributed, holonic manufacturing systems (Lee 2001, Rasmussen 2000, Sheridan 1985).

3.5 Challenges in Forest Operations Ecology – Izazovi u ekolo{koj pogodnosti {umskih radova Industrial Ecology is a scientific discipline that investigates human transformations of mass and energy from an ecosystem perspective (Ehrenfeld 2004, Erkman 1997, Kay 2002). Ecosystem perspective refers to the analysis and design of biophysical mass and energy transformation systems in order to maintain a situation which is ecologically sound, while providing humans with a sustainable livelihood. Forest Operations Ecology applies the principles of Industrial Ecology to Forest Operations Systems. It aims to develop and deploy environmentally sound forest operations technologies, to use resources efficiently, to minimize the overall production of waste and emissions, and to minimize impacts to structures and functions of environmental spheres (atmosphere, biosphere, hydrosphere, and lithosphere). The publication »Visionary manufacturing challenges for 2020« (BMED 1998) identified six grand challenges, one of which is relevant for forest operations ecology: to reduce production waste and environmental impacts to »near zero«. In our point of view, forest operations ecology, which is an operational approach to sustainability (Erkman 1997), will be facing the following challenges: Þ To adapt environmental performance indicators EPIs and environmental state indicators ESIs, as proposed by the ISO 14021 standard, to, and to establish a set of environmental performance standards for forest operations systems, Þ To analyze and evaluate environmental performance of harvesting and transportation systems by using Life Cycle Assessment LCA, or Substance Flow Analysis SFA, Þ To develop standards to monitor and report environmental performance metrics.

4. Conclusions – Zaklju~ci The voice of forest operations within the family of scientific communities has been weak. The forest operations community faces the problem of improving its scientific visibility, realigning its research efforts to the future challenges, and of strengthening its self-confidence. The paper aimed at (1) exploring Croatian Journal of Forest Engineering 28(2007)1


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the concept for worldviews (paradigms) that shaped the scientific development, (2) sketching a vision how forest operations could look like in 2020, (3) establishing a common understanding for the future of our discipline, and (4) discussing the major challenges that we will probably been facing. The investigation resulted in three major findings. First, five paradigmatic periods of developments could be identified: the utilization paradigm, the Tayloristic paradigm, the mechanization paradigm, the systems paradigm, and the network paradigm. Second, we are presently entering a new phase of development, characterized by the »network paradigm« that consists of network-based forest operations systems that are built of self-organized »cells«. Third, those network-based, self-organizing systems will face us with some challenges. The concurrency of spatially distributed coordination and operation activities is one of those challenges, requiring management to go from arts to science. Algorithmic methods and control processes will be a backbone of distributed, coordinated decision-making, and of supply chain management. Forest ergonomics will face the challenge to overcome the problem of »2nd-generation management applied to 5th-generation technology« by redesigning the human-organization interface. The quantification of the »industrial metabolism« of forest operations systems will be another challenge that we have to tackle with. It will hopefully move environmental performance evaluation from »good feelings« to hard facts. The author intended to trigger a broad discussion on the future direction of our discipline, forest operations engineering and management, and to induce the redesign of curricula. This is going along with his vision that the forest operations engineering and management community will regain its strengths and become more visible within the family of scientific communities.

5. References – Literatura Aoyama, M., 2002: Metrics and analysis of software architecture evolution with discontinuity. Proceedings, 5th International Workshop on Principles of Software Evolution [IWPSE '02],103–107, Orlando, Florida, May 19–20, 2002. Ashe, W. W., 1916: Cost of Logging Large and Small Timber. Forestry Quarterly (Journal of Forestry) 14: 441–452. Bare, B. B., Briggs, D. G., Roise, J. P., Schreuder, G. F., 1984: A survey of systems analysis models in forestry and the forest products industries. European Journal of Operational Research 18(1): 1–18. Berners-Lee, T., 1998: The World Wide Web: A very short personal history. available at http://www.w3.org/People/Berners-Lee/ShortHistory.html. accessed Mar-12-07. Croatian Journal of Forest Engineering 28(2007)1

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BMED, 1998: Visionary Manufacturing Challenges for 2020. Board on Manufacturing and Engineering Design. Washington, D.C.: National Academy Press. 172 p. Boulding, K. E., 1956: General Systems Theory – The Skeleton of Science. Management Science 2(3). Braniff, E. A., 1912: Scientific management and the lumber business. A possible field for foresters. Forestry Quaterly 10(1): 7–14. Brewer, J. D., Hsiang, S. M., 2002: The 'ergonomics paradigm’: foundations, challenges and future directions. Theoretical Issues in Ergonomic Sciences 3(3): 285–305. Church, R. L., Murray, A. T., Weintraub, A., 1998: Locational issues in forest management. Location Science 6 (1-4): 137–153. Colombo, A. W., Schoop, R., Neubert, R., 2006: An AgentBased Intelligent Control Platform for Industrial Holonic Manufacturing Systems. IEEE Transactions on Industrial Electronics 53(1): 322–337. Davis, I., Stephenson, E., 2006: Ten trends to watch in 2006. The McKinsey Quarterly, (Jan-2006): available at http:/ /www.mckinseyquarterly.com/article_page.aspx?ar=173 4&L2=18&L3=30. accessed Feb-04-2007. Duhamel du Monceau, H.-L., 1761: Art du charbonnier, ou Mannière de faire la charbon de bois. Paris: Desaint & Saillant. IV, 30, 1 pl. pp. Duhamel du Monceau, H.-L., 1764: De l’exploitation des bois ou moyens de tirer un parti avantageux des taillis, demi-futaies et hautes-futaies et d’en faire une juste estimation : avec la description des arts qui se pratiquent dans les forêts; faisant partie du traité complet des bois & des forests. Paris: H. L. Guerin & L. F. Delatour. Duhamel du Monceau, H.-L., 1767: Du transport, de la conservation et de la force des bois ou l’on trouvera des moyens d’attendrir les bois, de leur donner diverses courbures, sur-tout pour la construction des vaisseaux et de former des pieces d’assemblage. Paris: Chez L.F. Delatour. XXXII, 556 pp. Dykstra, D. P., 1976: Timber Harvest Layout By Mathematical and Heuristic Programming. Department of Industrial and General Engineering, Oregon State University. Corvallis, OR. PhD Thesis. 299 p Dykstra, D. P., Riggs, J. L., 1977: An application of facilities location theory to the design of forest harvesting areas. AIIE Transactions 9(3): 270–277. Ehrenfeld, J., 2004: Industrial ecology: a new field or only a metaphor? Journal of Cleaner Production 12: 825–831. Erkman, S., 1997: Industrial ecology: an historical view. Journal of Cleaner Production 5 (1/2): 1–10. Fisher, R. A., 1925: Statistical methods for research workers. Biological monographs and manuals. Edinburgh, London: Oliver and Boyd. ix, 239 pp. Fisher, R. A., 1935: The design of experiments. Edinburgh, London: Oliver and Boyde. xi, 252 pp. Gersick, C. J. G., 1991: Revolutionary Change Theories: A Multilevel Exploration of the Punctuated Equilibrium Paradigm. Academy of Management Review 16(1): 10–36.

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Hollnagel, E., 2001: Extended cognition and the future of ergonomics. Theoretical Issues in Ergonomic Sciences 2(3): 309–315. Hopper, J. E., 1973: Systems Analysis: A Tool for Woodland Decisions. Proceedings, Planning and Decisionmaking As Applied to Forest Harvesting, ed. J.E. O’Leary, 1–5. Corvallis, OR, USA, Forest Research Laboratory, School of Forestry, Oregon State University. Huan, S. H., Sheoran, S. K., Wang, G., 2004: A review and analysis of supply chain operations reference (SCOR) model. Supply Chain Management 9(1): 23–29. IEEE, 1998: IEEE Standard for Application and Management of the Systems Engineering Process. The Institute of Electrical and Electronics Engineers, Inc. New York. IEEE Standard, 1220–1998. 76 p. Kay, J. J., 2002: On Complexity Theory, Exergy and Industrial Ecology: Some Implications for Construction Ecology. In Construction Ecology: Nature as the Basis for Green Buildings, C. Kibert, J. Sendzimir, and B. Guy, Editors. Spon Press. p. 72–107. Kleiner, B. M., 2002: Computer-aided macroergonomics for improved performance and safety. Human Factors and Ergonomics in Manufacturing 12(3): 307–319. Kleiner, B. M., 2004: Macroergonomics as a large worksystem transformation technology. Human Factors and Ergonomics in Manufacturing 14(2): 101–115. Kleiner, B. M., 2006: Macroergonomics: Analysis and design of work systems. Applied Ergonomics 37(1): 81–89. Koroleff, A., 1952: Logging Mechanization in the U.S.S.R. A Review of Russian Data. Montreal, Canada: Pulp and Paper Research Institute of Canada. 158 p. Kuhn, T. S., 1970: The structure of scientific revolution. 2nd Ed. Chicago: University of Chicago Press. Lee, J. D., 2001: Emerging challenges in cognitive ergonomics: managing swarms of self-organizing agent-based automation. Theoretical Issues in Ergonomic Sciences 2(3): 238–250. Loch, C., 1998: Operations Management and Reengineering. European Management Journal 16(3): 306–317. Lundell, S., 2003: The need for a new forest technology – international co-operation among forestry, R&D and machine manufacturers [keynote address], Skogforsk. Växjö, Sweden. May 12–15, 2003. MacDonald, P., Clow, M., 2003: What a Difference a Skidder Makes: The Role of Technology in the Origins of the Industrialization of Tree Harvesting Systems. History and Technology 19(2): 127–149. Martell, D. L., Gunn, E. A., Weintraub, A., 1998: Forest management challenges for operational researchers. European Journal of Operational Research 104(1): 1–17. McCraw, W. E., Silversides, C. R., 1970: Analysis of tree harvesting machines and systems: a methodology. Forest Management Institute. Ottawa, Canada. Information Report, FMR-X-27. 184 p. Moridera, A., Murano, K., Mochida, Y., 2000: The Network Paradigm of the 21st Century and Its Key Technologies. IEEE Communications Magazine 38(11): 94–98. Croatian Journal of Forest Engineering 28(2007)1


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Newnham, R. M., 1966: A simulation model for studying the effect of stand structure on harvesting pattern. Forestry Cronicle 42: 39–44. Newnham, R. M., 1967a: A FORTRAN programme to simulate pulpwood harvesting machines. Forest Management Research and Services Institute. Ottawa, Canada. Information Report, FMR-X-7. 32 p. Newnham, R. M., 1967b: A progress report on the simulation model for pulpwood harvesting machines. Forest Management Research and Services Institute. Ottawa, Canada. Information Report, FMR-X-6. 41 p. Newnham, R. M., 1970: Productivity of harvesting machines designed for thinning: estimation by simulation. Forest Management Research and Services Institute. Ottawa, Canada. Information Report, FMR-X-25. 29 p. Newnham, R. M., 1971: CANLOG – The New CFS Harvesting Machine Simulator. Pulp and Paper Magazine of Canada 72(3): 107–112. Newnham, R. M., 1973: Simulation Techniques and Their Possible Application to Forest Harvesting in Canada. Proceedings, Planning and Decisionmaking As Applied to Forest Harvesting, ed. J.E. O’Leary, 125–138. Corvallis, OR, USA, Forest Research Laboratory, School of Forestry, Oregon State University. Newnham, R. M., Sjunnesson, A., 1969: A FORTRAN program to simulate harvesting machines for mechanized thinning. Forest Management Research and Services Institute. Ottawa, Canada. Information Report, FMR-X-23. 48+[25] p. Porter, M. E., 1985: Competitive advantage creating and sustaining, superior performance. New York: The Free Press. XVIII, 557 pp. Quade, E. S., 1968a: Introduction [into Systems Analysis and Policy Planning]. In Systems Analysis and Policy Planning. Applications in Defense, E. S. Quade and W. I. Boucher, Editors. American Elsevier Publishing Company: New York. p. 1–19. Quade, E. S., 1968b: Principles and Procedures of Systems Analysis. In Systems Analysis and Policy Planning. Applications in Defense, E. S. Quade and W. I. Boucher, Editors. American Elsevier Publishing Company: New York. p. 30–53. Rasmussen, J. R., 2000: Human factors in a dynamic information society: where are we heading? Ergonomics 43(7): 869–879. Samset, I., 1966: Utviklingen av skogbrukets driftsmethoder II. Loven om den sprangvise vikling. [Norwegian, the development of forest operations technology II. The law of discontinuous evolution]. Norsk Skogbruk 20: 737–741. Samset, I., 1992: Forest operations as a scientific discipline. Meddelelser fra Skokforsk 44(12): 1–48. Savage, C. M., 1990: Fifth generation management: Integrating enterprises through human networking. Bedford, MA: Digital Press. xvi, 267 p. pp. Sheridan, T. B., 1985: Forty-Five Years of Man-Machine Systems: History and Trends. In IFAC Proceeding Series,

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[umarsko in`enjerstvo i upravljanje {umskim radovima – osvrt na put unazad i naprijed znanstvene discipline Rad opisuje pet paradigmi faza razvoja, prikazuje viziju sustava izvo|enja {umskih radova 2020. godine, predla`e definiciju {umarskoga in`enjerstva i upravljanja {umskim radovima kao znanstvene discipline, te razmatra izazove za in`enjerstvo pridobivanja i prijevoza drva, upravljanje {umskim radovima, ergonomiju u {umarstvu i ekolo{ku pogodnost {umskih radova. Znanstvene su se discipline stalno razvijale sli~no biolo{kim sustavima. Kuhn je (1970) pru`io model »isprekidane ravnote`e« za znanstvene discipline, u kojem je razdoblja stabilnoga stanja nazvao »normalna znanost«, a razdoblja diskontinuirane promjene »znanstvena revolucija«. Uveo je naziv »paradigma« za odre|ivanje specifi~noga razdoblja stabilnoga stanja »normalne znanosti«, koji definira znanstvenu misao, odre|uje zna~ajne probleme i oblikuje vrstu pitanja koje treba istra`iti. Pri tome se kroz povijest mo`e prepoznati 5 paradigmi: paradigma kori{tenja, Taylorova paradigma, paradigma mehanizacije, paradigma sustava i paradigma mre`e. Istra`ivanje se temelji na pretpostavci da se evolucije {umarskoga in`enjerstva i upravljanja {umskim radovima mo`e odrediti dvjema glavnim dimenzijama: (1) znanstvenim teorijama i postupcima (os x na slici 1) te (2) uo~enom i istra`enom razinom slo`enosti prou~avanih objekata (os y na slici 1). Organiziranje {umskih radova zbog potra`nje tr`i{ta otpo~elo je u 17. stolje}u te se paradigma kori{tenja definira uglavnom pove}anjem potra`nje za drvom. Pojava industrijskoga in`enjerstva kao znanstvene discipline na po~etku 20. stolje}a potaknula je sustavno ispitivanje radnih procesa studijem rada i vremena te razvoj temeljne obuke radnika. Taylor (1895, 1903, 1911) uvodi studij rada i vremena kao vode}u metodologiju te se stoga druga faza razvoja nazova Taylorova paradigma jer dolazi do promjene gledi{ta na rad koji se mo`e deterministi~ki oblikovati i kontrolirati. Taylorovom paradigmom zapo~inje osnivanje znanstvenih skupina posve}enih istra`ivanju {umskoga rada. Uvo|enjem studija rada i vremena u {umarstvo nastaje »zakon obujma komada« koji obja{njava da se utro{ak vremena po jedinici proizvoda smanjuje s pove}anjem obujma komada. Problem kretanja po bespu}u bio je odlu~uju}i za pokretanje mehaniziranja {umskih radova nakon Drugoga svjetskoga rata. Od 1950. do 1970. godine vrijeme je najve}ega razvoja mehaniziranja radova, a utjecaj toga razdoblja o~ituje se i danas. To se razdoblje razvoja naziva »paradigma mehanizacije«. Znanstveni napori urodili su trima tipovima novih strojeva koji su pokrenuli revoluciju pridobivanja drva: motorna pila, skider te kamion za prijevoz drva. Usporedno se razvija nova znanstvena disciplina: ergonomija. Razvoj razli~itih strojeva doveo je do slo`enosti izvo|enja {umskih radova jer ima vi{e rje{enja za izvo|enje odre|enoga {umskoga rada. Stoga se javlja potreba procjene najprikladnijih radnih procesa u pridobivanju drva. Razvijaju se nove teorije za rje{avanje problema poznate kao »teorija sustavâ«, koja obuhva}a in`enjerstvo sustava, analizu sustava i teoriju upravljanja. To se razdoblje mo`e imenovati kao paradigma sustavâ jer je promijenila na~in mi{ljenja i dovela do uvo|enja visoko mehaniziranih sustava pridobivanja drva koji }e biti dominantni dugi niz godina. Quade je (1968a) prikazao razvrstvanje problema s kojima se bavi analiza sustava (tablica 1). Analiza sustava odre|uje metode za oblikovanje i upravljanje novih sustava koje treba uvesti u radove. Pri tome simulacija istra`ivanja pokazuje mnoge prednosti nad terenskim mjerenjima: br`a je, mogu}e je mijenjati parametre strojeva bez tro{kova prilagodbe stvarnoga stroja za mjerenja, stroj se mo`e ispitati u {irem opsegu sastojinskih uvjeta temeljenih na podacima stvarnih ili hipotetskih sastojina te se mo`e eliminirati prirodna varijacija izme|u sastojinskih uvjeta. Sustavna analiza u u`em smislu ima cilj da se pove}a u~inkovitost sustava ~ovjek – stroj. Daljnje pove}anje zadataka prema strojevima i ~itavu sustavu dovodi do stati~kih odnosa izme|u sastavnica sustava rezultitraju}i gubitkom fleksibilnosti i prilagodbe sustava. Centralizirani sustavi sa stati~kim odnosima izazivaju prekid zbog gre{ke jedne sastavnice. Nova struktura za prevladavanje problema mora biti mje{avina autonomno raspodijeljenih, inteligentnih, gre{kovno tolerantnih i uvijek upotrebljivih izvedbenih jedinica. Internetska tehnologija postaje klju~ni pokreta~ tehnologije stvaraju}i prostor za razmjenu informacija i dinami~ku raspodjelu zadataka. Ta se faza razvoja naziva mre`nom paradigmom koju karakterizira dinami~ka raspodjela radova izme|u jedinica i povezivanje jedinica uz mogu}nosti novih na~ina suradnje i me|udjelovanja ljudi i slo`enih sustava. Porter je (1985) utvrdio devet aktivnosti koje bi trebali dramati~no promijeniti na~in razmi{ljanja o proizvodnji i izvo|enju radova: ulazna logistika, radovi, izlazna logistika, marketing i prodaja, usluge i aktivnosti

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podr{ke, dobava, razvoj tehnologije, upravljanje ljudskim potencijalima, infrastruktura poduze}a. Porterov je rad potaknuo osnivanje mnogih disciplina poput logistike i upravljanja lancem dobave, koje su u{le u podru~je izvo|enja {umskih radova. Cilj je {umarskoga in`enjerstva i upravljanja {umskim radovima razumijevanje osnovnih na~ela koja ~ine podlogu pona{anja sustava {umskih radova i razvoj koncepata, metoda i alata koji podr`avaju oblik, primjenu, rad i stalno pobolj{anje tih sustava. Ova je znanstvena disciplina orijentirana prema problemu s ciljem pru`anja oblika, planova, rasporeda i mehanizama kontrole koji su: Þ biofizi~ki u~inkoviti s obzirom na fizikalne zakone, na~ela in`enjerstva te okoli{ine odnose {umskih ekosustava Þ ekonomski u~inkoviti s obzirom na tro{kove i koristi kratkoro~nih i dugoro~nih posljedica Þ individualno uskla|eni s obzirom na sprje~avanje negativnih u~inaka na zdravlje, sprje~avanje negativnih u~inaka na psihosocijalnu dobrobit, njegovanje razvoja osobnih vje{tina i stavova i promicanje socijalne razboritosti Þ okoli{no prihvatljivi s obzirom na utjecaj na prirodni dru{tveni okoli{ i u~inkovitu uporabu prirodnih resursa uklju~uju}i neobnovljive i obnovljive izvore, vodu, energiju i prostor Þ institucionalno prihvatljivi s obzirom na zakone, odredbe te preporuke u skladu s izvo|enjem {umskih radova, ciljevima zemljoposjednika ({umovlasnika) i dru{tvenim vrijednostima. In`enjerstvo pridobivanja i prijevoza drva na}i }e se pred problemima dosezanja konkurentnosti u izvo|enju svih radova, pred potrebom restrukturiranja proizvodnih poduze}a radi prilagodbe na promjene i razvoja inovativnih radnih procesa. Stoga }e morati do}i do razvoja fleksibilnih kontrolnih algoritama koji }e omogu}iti precizno upravljanje radnim procesima u vremenu i prostoru, razvoja autonomnih jedinica pridobivanja drva i transporta s upravlja~kom i suradni~kom inteligencijom, primjene znanja o okoli{no prihvatljivim tehnologijama pridobivanja drva u zemljama u razvoju te primjene znanja o visoko mehaniziranim tehnologijama u zemljama u tranziciji. Upravljanje {umskim radovima suo~it }e se s potrebama pomaka poslovnoga upravljanja prema upravljanju lancem dobave drva primjenom referentnih modela radova, razvoja matemati~koga oru|a za dono{enje odluka i prepoznavanja optimalnih rje{enja za slo`ene probleme pomo}u inteligentnih tehnika (geneti~ki algoritmi), povezivanja modela optimizacije s terenskim uvjetima te premo{tavanja razlika u teoriji i praksi upravljanja lancem dobave. Ergonomija u {umarstvu suo~it }e se s izazovima kako pro{iriti znanje op}e ergonomije u zemljama u razvoju i uvesti norme rada prilago|ene specifi~nostima podru~ja, radnim uvjetima i biomehani~kim i fiziolo{kim osobinama radnika. Budu}i se izazovi u izvo|enju {umskih radova na ekolo{ko prihvatljiv na~in o~ituju u usvajanju okoli{nih pokazatelja prema normi ISO 14021, postavljanju skupa okoli{nih normi za sustave izvo|enja {umskih radova i normi za pra}enje i izvje{tavanje o okoli{nom na~inu izvo|enja radova te uvo|enje analize i ocjenjivanja okoli{noga utjecaja. Namjera je autora bila da potakne {iru raspravu o budu}em usmjeravanju na{e discipline, {umarskoga in`enjerstva i upravljanja {umskim radovima, te da potakne preoblikovanje nastavnoga programa. To ide zajedno s autorovom vizijom da }e znanstvena disciplina {umarsko in`enjerstvo i upravljanje {umskim radovima vratiti svoju snagu i postati uo~ljivo u obitelji znanstvenih zajednica. Klju~ne rije~i: {umski radovi, {umarsko in`enjerstvo, paradigme, budu}i izazovi, znanstvena disciplina, povijesni razvoj

Received (Primljeno): February 2, 2006 Accepted (Prihva}eno): March 22, 2007 Croatian Journal of Forest Engineering 28(2007)1

Author’s address – Autorova adresa: Prof. Hans Rudolf Heinimann, PhD. e-mail: hans.heinimann@env.ethz.ch Institute of Terrestrial Ecosystems ETH Zurich Universitaetstrasse 22 CH–8092 Zürich SWITZERLAND

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Subject review – Pregledni ~lanak

Faculty of Forestry, University of Zagreb and Department of Forest Engineering in the Bologna Process Ante P. B. Krpan Abstract – Nacrtak The paper presents the past course and achievements of the reform of the higher educational system at the Faculty of Forestry of the University of Zagreb. The reform is part of the effort undertaken in order to include the Faculty in the European Area of Higher Education (EHEA) and the European Research Area (ERA). A three-cycle educational system has been adopted and the curricula for undergraduate, graduate and postgraduate studies have been devised on a 3 +2 +3 (2) or 180 + 120 + 180 (120) ECTS points basis. Three undergraduate studies have been established: Forestry, Urban Forestry and Wood Technology, whose programmes are already followed by two generations of students. The following graduate study programmes have been developed: Forestry and Urban Forestry, Nature and Environment Protection and Wood Technology Processes and Design of Wood Products. Graduate studies in the Forestry department contain two programmes: Silviculture and Forest Management with Wildlife Management and Techniques, Technologies and Management in Forestry. An improved proposal for doctoral study has been developed in the Forestry Department consisting of three programmes (Silviculture and Wildlife Management, Techniques, Technologies and Management in Forestry, and Urban Forestry, Nature Protection, Forest Management and Protection), as well as a doctoral study programme Wood Technology. Specialist postgraduate studies have been devised in ten programmes. Keywords: Faculty of Forestry Zagreb, reform of higher educational system

1. Introduction – Uvod The reform of the higher educational system was initiated at the Ministerial Conference in Bologna in 1999 with the issue of the famous Bologna Declaration and has been further developed at subsequent biannual conferences of the European Union Ministers. The Bologna Declaration is the core document for the reform of the higher educational system in the European Area of Higher Education (EHEA). Its signatories are ministers of education of 29 European countries gathered at a Ministerial Conference in Bologna on 19 June 1999. Croatia accepted and signed the document at a Ministerial Conference in Prague in 2001. By signing the Declaration, Croatia adopted the European higher educational system of undergraduate and graduate studies, while by agreeing to the proposals of doctoral studies put forth at the Berlin Ministerial Conference in 2003, it completed a Croatian Journal of Forest Engineering 28(2007)1

three-tier cycle of the higher education – undergraduate, graduate and doctoral. The higher educational system has been reformed with the goal of providing more purposeful education and enabling competent and skilled young experts to join global economic trends and create their own careers. The criteria of excellence, competence and mobility rank high in this reform. Guidelines for the development of higher educational and research processes in the European area are contained in a number of political and professional decisions and documents of the European Union. The European Council convened in Lisbon in March 2000, where the representatives of the governments of the European Union passed knowledge-based strategic goals intended to increase employment and strengthen economic reforms and social cohesion in the decade to come (»to become the most competitive

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and dynamic knowledge-based economy in the world capable of sustainable economic growth with more and better jobs and greater social cohesion«). The strategy has been elaborated in a number of recommendations, communications and action plans, which served as a basis for the issue of key guidelines at the highest political level: Towards a European Research Area, The European Research Charter, The Code of Conduct for the Recruitment of Researchers, Action Mobility Plan, Science and Society Action Plan, and Action Plan 3%. The reform of the higher educational system on the Bologna principles in Croatia was regulated at the national level by the 2003 Act on Scientific Activity and Higher Education and by subsequent amendments and other University documents. The National Institute of Science, Higher Education and Technological Development of the Republic of Croatia took part in the reform of doctoral studies by issuing ten core principles for the organisation of doctoral studies. The National Council for Higher Education of the Republic of Croatia passed the Principles for the Organisation of Postgraduate Doctoral Studies on July 14, 2006, consisting of General Principles, Principles of Study, and Organisational and Financial Principles. The Faculty of Forestry in Zagreb is the oldest institution of higher specialist education in south-eastern Europe. It dates back to 1860, when the High School of Agriculture and Forestry was established in Kri`evci and to 1898, when the Forestry Academy was founded in Zagreb. From 1920 to 1960 it was part of the Faculty of Agriculture and Forestry of Zagreb University and later became an independent faculty within the University of Zagreb. Overall, 4,580 students of forestry and 1,647 students of wood technology have graduated from the Faculty to date. The academic titles of Master of Science and Master Specialist have been acquired by 343 students, of which 246 titles account for the scientific field of forestry and 97 for the scientific field of wood technology. A total of 190 doctoral theses have been defended, with 139 titles in the scientific field of forestry and 51 titles in the scientific field of wood technology. According to the Faculty’s historical documents, all the changes in teaching plans have been undertaken with the view of coordinating the educational profile and the necessary knowledge with the increasing demands of the profession and growing specialist and scientific insights. Immediately prior to the Bologna Declaration (2000) and in response to growing demands for differentiated knowledge within the profession, the Faculty conducted a reform by introducing a module educational system. All the teachers at the Faculty of Forestry contributed to the

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latest reform of the educational system with debates and proposals at the department level. In order to achieve compatibility as a basic prerequisite for free subject mobility in the European educational system, the commissions preparing the proposals drew upon the previously mentioned principles and upon their own and other experience, in particular the experience of forestry faculties in Germany, Austria, the Czech Republic, Slovakia, Hungary, Slovenia and other EU member countries. Apart from experts at the Faculty of Forestry, the reform has also attracted the participation of experts in the Ministry of Agriculture, Forestry and Water Management of the Republic of Croatia, the Academy of Forest Sciences and the Forestry Institute of Jastrebarsko, who have organized a number of workshops. The forestry operative has taken part via the Croatian Forestry Society, as well as via the management and specialist services of the company Hrvatske [ume Zagreb. Members of the Department of Forest Engineering have also taken an active interest in the reform. The higher educational system at the Faculty of Forestry of the University of Zagreb has been reformed according to the system of three educational cycles based on a 3 + 2 + 3 (2) scheme, or 180 + 120 + 180 (120) ECTS points.

2. The reformed study structure at the Faculty of Forestry – Struktura reformiranoga studija na [umarskom fakultetu Up to the Bologna reform, the four-year study programme at the Faculty of Forestry put forth two profiles of experts with Bachelor degrees in forestry and in wood technology. The postgraduate study system led to the degrees of Master of Science, Master Specialist and Doctor of Science. A three-tier system of higher education was adopted with the Bologna reform: undergraduate, graduate and postgraduate. The scheme is given in Figure 1.

2.1 Undergraduate study – Preddiplomski studiji According to Figure 1, three undergraduate study programmes have been devised at the Faculty of Forestry and adopted by the University of Zagreb: a) Forestry, b) Urban Forestry, Nature Conservation and Environmental Protection and c) Wood Technology. Educational undergraduate study programmes last for three years (6 semesters). Students are required to collect 30 ECTS points or 180 ECTS points Croatian Journal of Forest Engineering 28(2007)1


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Fig. 1 Structure of the higher educational system at the Faculty of Forestry, University of Zagreb Slika 1. Struktura visokoobrazovnoga sustava na [umarskom fakultetu Sveu~ili{ta u Zagrebu throughout the duration of the study. The courses are compulsory and optional, lasting for one semester with additional values of ECTS points. By completing the undergraduate study students obtain the title of baccalaureate (BSc.), acquire competences for individual and team work in private entrepreneurship and specialist jobs in forestry, urban forestry, nature conservation and environment protection, wood processing and manufacture, as well as competences for the enrolment into graduate studies. Enrolment into the programme and programme course is defined by the Faculty Statute and by other acts. Student mobility in the undergraduate programme is expressed by their ability to choose optional courses at three levels: from other undergraduate programmes at the Faculty of Forestry in Zagreb, from biotechnology studies in Croatia and from studies at other faculties and polytechnics in the country and abroad. Croatian Journal of Forest Engineering 28(2007)1

2.2. Graduate study – Diplomski studiji The Faculty offers graduate study programmes for the educational profile in Forestry, Urban Forestry, Nature Conservation and Environmental Protection, as well as programmes for the study of Wood Technology Processes and Design of Wood Products. The graduate Forestry study has two programmes: Silviculture and Management Planning with Wildlife Management and Techniques, Technologies and Management in Forestry. The study lasts for two years or four semesters and requires 120 ECTS points in all. By completing the study, students acquire the academic title of Master according to the completed study (e.g. master of forestry – technique, technology and management). The number of optional courses per semester is significantly greater compared to the undergraduate study and offers wider possibilities for forming an individual educational profile. The study also provi-

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des better possibilities for horizontal and vertical student mobility across domicile and foreign educational institutions. Candidates in the study programmes develop managing competences and the ability to make independent and team business decisions, take part in developmental professional courses, as well as continue education in doctoral studies. By completing graduate studies, students obtain the necessary knowledge and skills for complex forestry tasks, ranging from the lowest forest structural units such as forest offices and districts to the highest ones on a vertical scale, such as county and republican institutions with jurisdiction over forestry. The scope of employment also includes inspection services, businesses and tasks in forest entrepreneurship, jobs and tasks in developmental, scientific and educational institutions, trade with forest products at home and foreign markets, trade with equipment, tasks in professional publishing and forestry-related media; complex jobs in urban forestry and forest and nature protection, as well as sawmilling and wood processing.

2.3 Postgraduate study – Poslijediplomski studiji The Faculty of Forestry of the University of Zagreb has a long tradition of postgraduate education, first through the writing and defence of doctoral theses, and in later periods through the establishment of master’s scientific and specialist study programmes. The first doctorate at the Faculty (Agricultural-Forestry Faculty) was defended on 4 June 1923. Before that, doctoral theses had been submitted to and defended at foreign faculties or at the Faculty of Philosophy of Zagreb University, whose constituent part was the Forestry Academy from 1898 to 1918. So far a total of 190 doctoral theses have been defended at the Faculty of Forestry, University of Zagreb. Postgraduate study of forestry and wood technology (leading to a master’s and master specialist degrees, as well as doctoral studies) in several scientific fields were established in 1960 after the Faculty of Forestry became an independent institution. The first master’s degree was defended on 31 August 1964. A total of 343 masters of sciences and master specialists theses have since been submitted at both Faculty departments, of which 246 in the Forestry department. Postgraduate study programmes are regarded as a component of lifelong learning, especially in the sense of new knowledge transfer during high-quality research and professional training and during its application in practice.

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According to past experience, the following partners have expressed interest in postgraduate studies: the public economic sector, in the first place the state company for the management with state-owned forests (79% of all forests in Croatia) whose 9,500 and more employees work in over 170 regionally distributed organisational units; state administration (management and inspection services of the Ministry of Agriculture, Forestry and Water Management and state administration offices in counties); the private sector represented by a broad scope of forestry entrepreneurs employed in forestry services (operational work, trade, promotion, etc.); interest associations of private forest owners; the scientific-research sector and all those who seek to benefit from such training by achieving increased competitiveness and improving their company businesses. 2.3.1 Doctoral study – Doktorski studiji Although doctoral studies were discussed at earlier ministerial conferences (Bologna 1999, Prague 2001), ministers of 33 European countries met in Berlin in 2003 to determine the priorities needed to accelerate the establishment of stronger links between the European Higher Education Area (EHEA) and the European Research Area (EHA), as well as introduce the third cycle of higher education (doctoral study) within the Bologna Process. The most important criteria that were highlighted included interdisciplinarity, a systematic approach to quality assurance in higher education, student and research mobility and excellence networking. »Doctoral studies are third-cycle studies which require original research for the acquisition of the academic degree of doctor of science (PhD.). Doctoral programmes are essential for the development of EHEA and ERA and represent a link between these two processes. The main responsibility for the training of researchers at different stages of their career is borne by universities. They must respond to the challenges of training young researchers not only to meet the needs of the academic market but also the needs of other sectors and labour markets such as industry, entrepreneurship, trade, public institutions and organisations, research organisations, etc.« The Rectors of European universities met in Graz in 2003 and issued a declaration on the Europe of Knowledge and the central role of universities in research and research-based higher education. They emphasised that competitiveness and excellence should be balanced with social cohesion and inclusion of growing numbers of people into higher education. The basic principles were set down stating that European universities will build their research Croatian Journal of Forest Engineering 28(2007)1


Faculty of Forestry, University of Zagreb and Department of Forest Engineering ... (123–136)

and innovative strategies in the spirit of the Europe of Knowledge. In June 2003 the European Commission passed, and the European Council and the European Parliament adopted a Communication addressing the need to develop research professions and research criteria. Care for the creation of a research career is a constituent part of a doctoral programme. The Communication provides basic guidelines to be realized by a doctoral programme: increase researcher employability through the development of general competences and skills needed for employment; restructure and reorganize doctoral programmes and include them in the Bologna Process; provide better organized training through a doctoral programme; systematically develop supervision and mentorship; fully integrate doctoral students in research, but also open the path to additional profiling of their careers outside the research area; ensure financing and adequate social rights for doctoral students, as well as organized approach to mobility. In 2004 the European University Association (EUA) initiated a project of doctoral programmes and attracted the participation of 49 European universities from 22 countries – EU members. The 2004 EUA conference in Maastricht devised a framework of institutional policy in the field of doctoral training. The 2005 Conference in Salzburg elaborated the EUA Doctoral Project recommendations and the Maastricht conclusions by putting forth a set of ten basic principles for the organisation of doctoral studies: doctoral study should be based on the advancement of knowledge through original research; doctoral study and the development of research careers should be imbedded in institutional strategies and policies; the rich diversity of doctoral programmes in Europe should be preserved; doctorate candidates should be recognized as early stage researchers or professionals with commensurate rights; supervision and assessment of candidates should be based on a transparent contractual framework of shared responsibilities that clearly define rights and obligations; doctoral programmes should seek to achieve critical mass of expertise through the creation of doctoral schools or excellence network; as a rule, doctoral training should last for 3 – 4 years full-time; the innovative programme structure and the development of general competences should be realized through interdisciplinarity; mobility should be increased, a number of obstacles removed and adequate financial instruments for its implementation ensured; appropriate funding and a system of developing quality doctoral programmes should be ensured. The conference held in Vienna in 2006 discussed the Charter and the Code and developed instruments for supporting doctoral candidates; clearly defined goals and projects of doctoral research; training plans and supervision plans for each individual doctoral Croatian Journal of Forest Engineering 28(2007)1

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candidate; a compulsory part of the programme through courses and modules; research-based colloquia and workshops; training for the acquisition of general skills; institutionalized monitoring and guidance through a candidate’s career; participation in the organisation of scientific events and taking responsibility for a part of the work (poster sections); participation in decision-making bodies. Programmes of postgraduate doctoral studies and postgraduate specialist studies have been set down at the Faculty of Forestry within the postgraduate study reform: doctoral Forestry study (two programmes) and doctoral Wood Technology study, as well as eight programmes of specialist forestry studies and two programmes of specialist wood technology studies (Figure 1). A temporary license was issued for the above programmes, which currently serve as the basis for the third higher educational cycle. Taking into consideration the reviewers’ and reporters’ comments related to the doctoral study programme of Forestry and the Principles for the Establishment of Postgraduate Doctoral Studies issued by the National Higher Education Council of the Republic of Croatia on 14 July 2006, as well as other domicile and European guidelines, we undertook to make an in-depth revision of the doctoral study programme with a view to meeting the European requirements and principles of doctoral training. The revision envisages one doctoral study of Forestry with three programmes: Þ Silviculture and Wildlife Management, Þ Techniques, Technologies and Management in Forestry, Þ Urban Forestry, Nature Protection, Forest Management and Protection. Doctoral studies last for three years. Students acquire ECTS points from three point groups. The first two point groups relate to teaching, from which a doctoral candidate collects 60 ECTS points or 20 points per semester, while the third group relates to extra-curricular activities, from which the candidate is required to collect 120 ECTS points. The first point group is made up of compulsory courses for all doctoral students. The second point group consists of optional courses in dependence of a study programme. The first semester in the field of doctoral study consists of courses that are compulsory for all study programmes. In the second and third semester all the courses are optional. Students are required to collect 20 ECTS points/semester or 60 ECTS points in all from the teaching part of the study. Instruction is held in the form of lectures (contributing to a maximum of 25% of the timetable), field/laboratory work and seminars. Focus is on the candidate’s inde-

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pendent work based on seminar papers. In the fourth, fifth and sixth semester students are required to collect 40 ECTS points/semester or a total of 120 ECTS points in extracurricular activities from the Third point group. Immediately upon enrolment, the candidate takes part in scientific-research work on projects and is required to publish his/her research results in leading professional and scientific journals. In the fourth, fifth and sixth semester a doctoral candidate spends some time abroad, publishes papers, prepares and defends a dissertation. A mentor is selected after the first semester. A candidate is obliged to enrol a minimum of 51% of optional courses from the programme of doctoral study, while the remaining 49% may be elected from other programmes or doctoral studies at domicile and other faculties and universities with bilateral contracts (after consultations with their mentors). The proposal of the doctoral study programme outlined above is currently being evaluated at the University of Zagreb. The high quality of doctoral study programmes will be ensured by the employment of competent mentors and teachers, the inclusion of candidates in scientific-research activities in home and international projects, suitable facilities and equipment, maximal profiling according to the candidateâ&#x20AC;&#x2122;s individual desires reflected in the choice of optional courses, as well as by mobility within postgraduate studies at domicile and foreign educational institutions. The doctoral study reform will allow doctoral candidates to become an organic component in educational and research processes and will enable accelerated acquisition and quality of their individual competences. Foreign institutions with which the Faculty of Forestry in Zagreb or the University of Zagreb have signed contracts on cooperation include BOKU, Vienna, Austria; University of Silesia in Katovice, Poland; Mendel University of Agriculture and Forestry, Brno; Biotechnological Faculty of the University of Ljubljana, Slovenia, and the Faculty of Forestry of the University of Sarajevo, Bosnia and Herzegovina. By obtaining the academic title of doctor of science, doctoral candidates acquire competences for independent and original scientific-research work, as well as develop the ability to objectively and critically evaluate other scientific projects, make scientific and academic advancements and promote their careers. The purposefulness of doctoral studies at the Faculty of Forestry of Zagreb University is reflected in the need of the Croatian forestry for doctors of science, particularly for purposes of sustaining and promoting scientific-research and educational components in the educational and scientific-research framework (Faculty of Forestry Zagreb, Forestry Ins-

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titute Jastrebarsko, polytechnics and secondary forestry schools), and their activities in productive and developmental services of forestry companies and affiliated activities. The researchers of the Faculty of Forestry in Zagreb and the Forestry Institute have for the past 35 years been firmly integrated in the technological development of forestry in Croatia (seven mid-term research programmes), thus ensuring high-educational and scientific basis for forest management and integration in global developmental trends. Full-time study organisation is based on an 8hour working day of students at the Faculty of Forestry, within which they attend lectures, participate in scientific-research work on scientific projects and teach in undergraduate and graduate study courses. Part-time study organisation entails attending lectures within doctoral study and participating in scientific projects at the Faculty of Forestry or the related faculties and scientific institutions in the country and abroad in the status of cooperator-researcher. 2.3.2. Specialist study â&#x20AC;&#x201C; Specijalisti~ki studiji Specialist studies are intended for further training of operative experts. The purposefulness of postgraduate specialist study is reflected in the needs of Croatian forestry for such an educational profile, and particularly for their work in production and developmental services of forestry companies and affiliated activities, as well as in the increasingly developing private sector. The study, based on scientific developments, promotes basic skills and the ability to solve complex production and developmental tasks individually or in a team. According to Figure 1, ten specialist study programmes in all have been proposed for evaluation, of which eight are from the field of forestry and two from the field of wood technology. Specialist studies last for two years or four semesters. A study candidate is required to collect a total of 120 ECTS points or 30 ECTS points per semester during the length of study. The weekly load may be maximally 12 hours (180 hours/semester). The first semester consists of compulsory courses of general importance for the study. In the second semester and the first half of the third semester all the courses are optional. Candidates are required to enrol 51% of the optional courses from the study programme, whereas the remaining 49% are elected from other studies at domicile and other faculties and universities (in consultation with mentors). A mentor is selected after the first semester. In the middle of the third and in the fourth semester the candidate writes and publishes papers, writes and defends his specialist work. During the Croatian Journal of Forest Engineering 28(2007)1


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Table 1 Graduate study of Forestry, programme: Technique, Technology and Management in Forestry Tablica 1. Program diplomskoga studija [umarstvo, smjer: Tehnike, tehnologije i menad`ment u {umarstvu Lectures Laboratory Field work Predavanja Vje`be Teren classes – sati days – dana 1st semester I. semestar

Compulsory courses Obvezni predmeti

Logging II Pridobivanje drva II Mechanisation of Timber Logging Mehanizacija pridobivanja drva Management and Entrepreneurship in Forestry Menad`ment i poduzetni{tvo u {umarstvu Forestry Policy and Legislation [umarska politika i zakonodavstvo Optional course 1 Izborni predmet 1 Optional course 2 Izborni predmet 2 Optional course 3 Izborni predmet 3 Total Ukupno

ECTS

3

2

3

7

3

2

3

7

2

2

2

6

2

4

1

2

1

2

1

2

13

6

8

30

Obligatory optional courses Obvezni izborni predmeti

Torrent Control Ure|ivanje bujica Sociology of Organization in Forestry Sociologija organizacije u {umarstvu Physical and Mechanical Properties of Wood Osnove tehnologije drva Humanisation of Work in Forestry Humanizacija rada u {umarstvu

2nd semester II. semestar Planning of Forest Road Network Otvaranje {uma Forest Products [umski proizvodi Integrated Forest Protection Integrirana za{tita {uma Silviculture Silvikultura Graduate paper Diplomski rad Optional course 1 Izborni predmet 1 Optional course 2 Izborni predmet 2 Optional course 3 Izborni predmet 3 Total Ukupno

2

2

2

6

2

1

2

4

2

1

2

4

2

2

3

5

5

1

2

1

2

1

2

11

6

9

30

Forest Product Trade Trgovina {umskim proizvodima Ergonomics of Forest Machines Ergonomija {umskih strojeva Mechanical Technologies of Wood Osnove mehani~ke preradbe drva Forest Fires [umski po`ari Forest Fire-Prevention Infrastructure [umska protupo`arna infrastruktura

rd

3 . semester III. semestar Design of Forest Roads Projektiranje {umskih prometnica Forestry Firm Economics Ekonomika {umarske tvrtke Marketing in Forestry Marketing u {umarstvu Digital Cartography in Forestry Digitalna kartografija u {umarstvu

2

2

4

6

2

1

1

5

2

1

3

2

1

3

Croatian Journal of Forest Engineering 28(2007)1

Technology of Forest Road Construction Tehnologije gradnje {umskih prometnica Evaluation of Forest Resources Vrednovanje {umskih resursa Forest Biomass for Energy [umska biomasa za energiju Planning of Technological Operations Planiranje tehnolo{kih operacija

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Lectures Laboratory Field work Predavanja Vje`be Teren classes – sati days – dana 4th semester IV. semestar

Compulsory courses Obvezni predmeti

Enviromentaly sound Technologies Okoli{no prihvatljive tehnologije Organization of Production in Forestry Organizacija proizvodnje u {umarstvu Forest Regulation and Planning Ure|ivanje {uma Graduate paper Diplomski rad Total Ukupno

Obligatory optional courses Obvezni izborni predmeti

ECTS

2

2

3

4

2

2

3

5

2

1

2

3

18

6

5

8

30

Table 2 Doctoral study in Forestry, programme: Techniques, Technologies and Management in Forestry – the first point group – Methodological (compulsory) courses Tablica 2. Doktorski studij [umarstvo, smjer: Tehnike, tehnologije i menad`ment u {umarstvu – Prva bodovna skupina – Metodolo{ki (obvezni) kolegiji Courses Predmeti

Total Ukupno

Methods and Techniques of Scientific-Research Work Metode i tehnike znanstvenoistra`iva~kog rada Design of Experiments and Statistical Modelling Planiranje pokusa i statisti~ko modeliranje Remote Sensing and GIS in Forestry Daljinska istra`ivanja i GIS u {umarstvu

Seminars Seminar

ECTS

20

5

10

5

4

20

5

10

5

4

24

10

10

4

5

study candidates are involved in scientific-research work (projects). The study is organized in such as way as to ensure horizontal and vertical student mobility. Horizontal mobility refers to studies within biotechnology and other studies at Croatian universities and abroad. Vertical mobility refers to the transition to doctoral studies. By completing the studies the candidate acquires competences for providing independent and team solutions to complex and very complex production and developmental professional tasks on scientific principles.

3. The position of the Department of Forest Engineering in the Bologna Process – Polo`aj Zavoda za {umarske tehnike i tehnologije u bolonjskom procesu As mentioned before, members of the Department were actively involved in the Bologna reform

130

Load, hours – Optere}enje, sati Lectures Laboratory Predavanja Vje`be

and contributed greatly to a successful presentation of programme proposals for undergraduate, graduate and postgraduate studies at the Faculty. The Department teachers hold courses on all educational programmes of the reformed study. They teach a large number of compulsory and optional courses in undergraduate studies. Of particular importance is the fact that forestry engineering has been highlighted through the creation of special educational programmes led by the Department members. Thus a special educational programme in the graduate study of Forestry, entitled Forestry – programme: Technique, Technology and Management in Forestry, whose programme is given in Table 1. Within the doctoral study in Forestry the Department also proposed and developed a programme of doctoral study entitled Techniques, Technologies and Management in Forestry. The programme consists of lectures (Tables 2 and 3) and extra-curricular activities (Table 4). The focus is placed on extracurricular Croatian Journal of Forest Engineering 28(2007)1


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Table 3 Doctoral study in Forestry, programme: Techniques, Technologies and Management in Forestry – the second point group – Optional courses Tablica 3. Doktorski studij [umarstvo, smjer: Tehnike, tehnologije i menad`ment u {umarstvu – Druga bodovna skupina – Izborni predmeti Courses Predmeti

Total Ukupno

Work and Time Study Studij rada i vremena Rationalisation of Wood Harvesting Operations Racionalizacija radova pridobivanja drva Forest Operations Management Upravljanje {umskim operacijama Cost Calculations of Harvesting Operations Kalkulacije tro{kova pridobivanja drva High-tech in Forest Harvesting Vrhunske tehnologije pridobivanja drva Marketing and Forest Products Trade Marketing i trgovina {umskih proizvoda Commercial Law Trgova~ko pravo Forest Harvesting and Enviroment Pridobivanje drva i {umski okoli{ Optimisation of Forest Road Infrastructure Optimizacija {umske prometne infrastrukture Primary and Secondary Forest Opening Primarno i sekundarno otvaranje {uma Computer Forest Road Design Ra~unalno projektiranje {umskih cesta Techniques and Technologies of Forest Road Building Tehnike i tehnologije izgradnje {umskih prometnica Prominent Properties of Wood Prominentne zna~ajke drva Management in Forestry Menad`ment u {umarstvu Corporation Management Korporacijsko upravljanje Business Ethics Poslovna etika Measurement Techniques on Forest Machines Tehnike mjerenja na {umskim strojevima Technical and Enviromental Suitability of Forest Machines Tehni~ka i okoli{na pogodnost strojeva Ergonomy in Forestry Ergonomija u {umarstvu

Seminars Seminar

ECTS

24

6

8

10

5

24

6

6

12

5

24

6

4

14

5

24

6

6

12

5

24

6

6

12

5

12

2

4

6

3

12

4

8

3

12

4

2

6

3

24

8

6

10

5

24

6

8

10

5

24

8

8

8

5

24

8

6

10

5

12

4

6

2

3

24

8

6

10

5

12

4

8

3

12

4

8

3

24

6

8

10

5

24

6

6

12

5

24

6

8

10

5

activities from which a doctoral candidate must collect 120 of a total of 180 ECTS points. Three proposals for a specialist study programme have been devised at the Department, of which two have passed the evaluation criteria while the third is currently being evaluated. The study programmes Forest Techniques and Technologies and Forest Roads Croatian Journal of Forest Engineering 28(2007)1

Load, hours – Optere}enje, sati Lectures Laboratory Predavanja Vje`be

have been approved. The third study programme is Management and Entrepreneurship in Forestry. Tables 5 and 6 present educational programmes of two specialist studies developed within the Department. As the evaluation of the specialist study programme Management and Entrepreneurship in Forestry is still under way, it is not given here.

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Table 4 Doctoral study in Forestry, programme: Techniques, Technologies and Management in Forestry – the third point group – Extracurricular activities (120 ECTS) Tablica 4. Doktorski studij [umarstvo, smjer: Tehnike, tehnologije i menad`ment u {umarstvu – Tre}a bodovna skupina – izvannastavne aktivnosti (120 ECTS) Scientific Ativity and Scientific Articles Znanstvena aktivnost i znanstveni radovi Conducting a scientific project (for young scientists) Vo|enje znanstvenog projekta (za mlade znanstvenike) Participation in a domicile scientific project Sudjelovanje na doma}em znanstvenom projektu Participation in an international scientific project Sudjelovanje na me|unarodnom znanstvenom projektu Scientific work published in a journal cited in 1st group databases (CC, SCI,...) Objavljen znanstveni rad u ~asopisu a1 skupine Scientific work published in a journal cited in 2nd group databases (CAB, Agricola,...) Objavljen znanstveni rad u ~asopisu a2 skupine Presentation at an international scientific meeting Prezentacija na me|unarodnom znanstvenom skupu (a3 skupina) Poster at an international scientific meeting Poster na me|unarodnom znanstvenom skupu Presentation at a domicile scientific meeting Izlaganje na doma}em znanstvenom skupu Poster at a domicile scientific meeting Poster na doma}em znanstvenom skupu Other articles (evaluated by the study’s organizer) Ostali ~lanci (prema ocjeni voditelja studija) Defending doctoral thesis Obrana teme doktorske disertacije Patents, books and parts of books (evaluated by the study’s organizer) Patenti, knjige i dijelovi knjiga (prema ocjeni voditelja studija) Awards, certificates and similar (evaluated by the study’s organizer) Nagrade, priznanja i sl. (prema ocjeni voditelja studija) Scientific training abroad (up to 1 month) Znanstveno usavr{avanje u inozemstvu (do 1 mj.) Scientific training abroad (from 1 to 3 months) Znanstveno usavr{avanje u inozemstvu (od 1 do 3 mj.) Scientific training abroad (more than 3 months) Znanstveno usavr{avanje u inozemstvu (vi{e od 3 mj.)

No. of ECTS points Broj ECTS bodova 15 5 5 30 (A*), 15 (K*) 20 (A), 10 (K) 15 (A), 5 (K) 10(A), 4 (K) 8 (A), 3 (K) 6 (A), 2 (K) 0–10 10 0–15 0–10 10 20 30

* A – first author – prvi autor, K – co-author – suautor

Table 5 of Specialist study programme in Forestry Techniques and Technologies Tablica 5. Program specijalisti~koga studija [umarske tehnike i tehnologije Load, hours – Optere}enje, sati Total Lectures Laboratory Ukupno Predavanja Vje`be 1st semester – Compulsory courses I. semestar – Obvezni predmeti Methods and Tech. of Scientific-Research Work with Experiment Planning 30 20 10 Metode i tehnike znanstvenoistra`iva~kog rada s planiranjem pokusa Statistical Methods and Models in Forestry 30 20 10 Statisti~ke metode i modeli u {umarstvu Remote Sensing and GIS in Forestry 40 16 12 Daljinska istra`ivanja s GIS-om Work and Time Study 40 16 14 Studij rada i vremena Measurement Techniques on Forest Machines 40 20 20 Tehnike mjerenja na {umskim strojevima Total 180 – – Ukupno Courses Predmeti

132

Seminars Seminar

ECTS

6

6

12

6

10

6

6

30

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Courses Predmeti

Load, hours – Optere}enje, sati Total Lectures Laboratory Ukupno Predavanja Vje`be 2nd semester –Optional courses II. semestar – Izborni predmeti

Forest Wood Products [umski drvni proizvodi Forest Non-Wood Products [umski nedrvni proizvodi Felling and Processing of Trees Sje~a i izradba drva Ground-based Timber Extraction Privla~enje drva po tlu Marketing of Forest Products Marketing {umskih proizvoda Cable Yarding and Aerial Logging @i~are i zra~ni transport drva Further Timber Transport Daljinski transport drva Technical Suitability of Forest Machines Tehni~ka pogodnost {umskih strojeva Abnormalities and Defects of Wood Nepravilnosti drva

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Seminars Seminar

ECTS

18

7

6

5

3

18

7

6

5

3

18

10

8

3

36

16

10

10

6

18

8

5

5

3

36

16

10

10

6

36

20

10

6

6

36

18

18

6

18

10

8

3

Total 180 – Ukupno rd ½ 3 semester – Optional courses ½ III. semestar – Izborni predmeti

30

18

10

6

2

3

18

10

6

2

3

18

8

10

3

18

8

10

3

18

8

10

3

18

10

8

3

18

12

6

3

18

6

12

3

15

270

45

270

45

120

High-tech in Forest Harvesting Vrhunske tehnologije pridobivanja drva Logistics in Forest Operations Logistika {umskih operacija Cost Calculations of Harvesting Operations Kalkulacije tro{kova {umskih operacija Anisotropy of Physical and Mechanical Properties of Wood Anizotropnost fizikalnih i mehani~kih zna~ajki drva Water in Trees and Wood Voda u drvetu i drvu Environmental suitability of Forest Machines Okoli{na pogodnost {umskih strojeva Entrepreneurship and Innovation in Forestry Poduzetni{tvo i inovacije Ergonomic in Forestry Ergonomija u {umarstvu

Total 90 Ukupno rd ½ 3 and 4th semester ½ III. semestar i IV. semestar Writing articles and preparation of thesis Pisanje ~lanaka, izrada specijalisti~kog rada Total Ukupno Overall Sveukupno

*In 2nd and 3rd semester students choose a minimum of 51 % of the listed subjects, and the rest from other programmes. *u 2. i 3. semestru studenti biraju najmanje 51% od navedenih predmeta, a ostatak iz drugih programa.

4. Conclusion – Zaklju~ak The Faculty of Forestry of the University of Zagreb is successfully addressing the compulsory postuCroatian Journal of Forest Engineering 28(2007)1

lates of the higher educational reform stemming from the Bologna principles. The majority of the designed educational programmes for undergraduate, graduate and postgraduate (doctoral and specialist) studies

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Table 6 Specialist study programme in Forest Roads Tablica 6. Program specijalisti~koga studija [umske prometnice Load, hours – Optere}enje, sati Total Lectures Laboratory Ukupno Predavanja Vje`be 1st semester – Compulsory courses I. semestar – Obvezni predmeti Methods and Tech. of Scientific-Research Work with Experiment Planning 30 20 10 Metode i tehnike znanstvenoistra`iva~kog rada s planiranjem pokusa Statistical Methods and Models in Forestry 30 20 10 Statisti~ke metode i modeli u {umarstvu Remote Sensing and GIS in Forestry 40 16 12 Daljinska istra`ivanja s GIS-om Work and Time Study 40 16 14 Studij rada i vremena Measurement Techniques on Forest Machines 40 20 20 Tehnike mjerenja na {umskim strojevima Total 180 – – Ukupno nd 2 semester – Optional courses II. semestar – Izborni predmeti Primary Forest Opening 36 18 18 Primarno otvaranje {uma Secondary Forest Opening 36 18 18 Sekundarno otvaranje {uma Methodologies of Forest Road Measurement 18 8 10 Metodologije izmjere {umskih cesta Computer Design of Forest Roads 36 14 22 Ra~unalno projektiranje {umskih cesta Technology of Forest Road Building 36 26 10 Tehnologije izgradnje {umskih prometnica High-tech in Forest Harvesting 18 10 6 Vrhunske tehnologije pridobivanja drva Bases of Forestry Business 18 12 6 Osnove poslovanja u {umarstvu Total 180 – – Ukupno rd ½ 3 semester – Optional courses ½ III. semestar – Izborni predmeti Legal Foundations of Planning, Design and Building Forest Roads 36 30 6 Zakonske osnove planiranja, projektiranja i izgradnje {umskih cesta Making a Forest Opening Study 36 14 22 Izrada studije otvaranja {uma Cable Yarding and Aerial Logging 18 9 9 @i~are i zra~ni transport Machines for Building Forest Roads 36 18 18 Strojevi za izgradnju {umskih prometnica Management in Forestry 18 10 8 Menad`ment poduze}a u {umarstvu Total 90 – – Ukupno rd th ½ 3 and 4 semester ½ III. semestar i IV. semestar Writing papers and preparation of thesis 270 – – Pisanje ~lanaka, izrada specijalisti~kog rada Total 270 – – Ukupno Overall – – – Sveukupno Courses Predmeti

Seminars Seminar

ECTS

6

6

12

6

10

6

6

30

6

6

3

6

6

2

3

3

30

6

6

3

6

3

15

45

45

120

*In 2nd and 3rd semester students choose a minimum of 51 % of the listed subjects, and the rest from other programms. *u 2. i 3. semestru studenti biraju najmanje 51% od navedenih predmeta, a ostatak iz drugih programa.

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Faculty of Forestry, University of Zagreb and Department of Forest Engineering ... (123–136)

have passed the process of evaluation and are currently being implemented. However, we must constantly bear in mind that every educational system is in continuous transition. Although during the preparation of the programme we adhered to the principles of responsibility and conscience, it is more than certain that the programmes of all educational degrees at the Faculty of Forestry will have to be permanently polished and improved in order to meet the reform objectives; provide young experts, competent promoters of the development of the profession and economy in the European framework, with rapid and successful training of the highest quality. The Department of Forest Engineering of the Faculty of Forestry in Zagreb has been entrusted with the honourable and responsible duty to develop and design special educational programmes related to forest engineering in the second and third educational cycle.

5. References – Literatura Anon, 2007: Doktorski studij [umarstvo – smjer: uzgajanje {uma i lovno gospodarenje; smjer: Tehnike, tehnologije i menad`ment u {umarstvu; smjer: Urbano {umarstvo, za{tita prirode, ure|ivanje i za{tita {uma. Rukopis, [umarski fakultet Sveu~ili{ta u Zagrebu (ur. A. P. B. Krpan, J. Vukeli}, B. Hra{ovec), 1–369. Anon, 2006: Preddiplomski i diplomski studij [umarstvo. [umarski fakultet Sveu~ili{ta u Zagrebu (ur. R. Pernar), 1–155. Anon, 2006: Prediplomski i diplomski studij Urbano {umarstvo, za{tita prirode i okoli{a. [umarski fakultet Sveu~ili{ta u Zagrebu (ur. M. Id`ojti}), 1–93.

A. P. B. KRPAN

Anon, 2006: Doktorski studij Drvna tehnologija. Rukopis, [umarski fakultet Sveu~ili{ta u Zagrebu (ur. M. Figuri}), 1–103. Anon, 2006: Specijalisti~ki studij [umarske tehnike i tehnologije. Rukopis. [umarski fakultet Sveu~ili{ta u Zagrebu (ur. A. P. B. Krpan), 1–73. Anon, 2006: Specijalisti~ki studij Management and Entrepreneurship in Forestry. Rukopis, [umarski fakultet Sveu~ili{ta u Zagrebu (ur. I. Martini}), 1–52. Anon, 2006: Specijalisti~ki studij [umske prometnice. Rukopis, [umarski fakultet Sveu~ili{ta u Zagrebu (ur. D. Pi~man), 1–49. Anon, 2006: Specijalisti~ki studij Organizacija proizvodnje. Rukopis, [umarski fakultet Sveu~ili{ta u Zagrebu (ur. M. Figuri}), 1– 23. Anon, 2006: Specijalisti~ki studij Tehnologija drvnih materijala. Rukopis, [umarski fakultet Sveu~ili{ta u Zagrebu (ur. V. Jambrekovi}), 1–25. Anon, 2006: Doktorski studiji. Nacionalna zaklada za znanost, visoko {kolstvo i tehnologijski razvoj Republike Hrvatske (ur. P. Lu~in), Trg J. J. Strossmayera 4, Zagreb, 1–168. Anon; 2004: Biomedicina i zdravstvo. Medicinska naklada, Zagreb, listopad 2004 (ur. Z. Lackovi}), 1–383. Anon, 1998: Sveu~ili{na {umarska nastava u hrvatskoj 1898–1998. Knjiga tre}a [umarski fakultet Sveu~ili{ta u Zagrebu – Pola stolje}a drvnotehnolo{ke nastave. [umarski fakultet Sveu~ili{ta u Zagrebu 1998 (ur. B. Ljuljka), 1–364. Anon, 1998: Sveu~ili{na {umarska nastava u hrvatskoj 1898–1998. Knjiga druga – Sto godina sveu~ili{ne nastave u Hrvatskoj. [umarski fakultet Sveu~ili{ta u Zagrebu 1998 (ur. S. Mati}), 1–709.

Anon, 2006: Studijski programi Drvnotehnolo{kog odsjeka. [umarski fakultet Sveu~ili{ta u Zagrebu (ur. R. Beljo Lu~i}), 1–110.

Sa`etak

[umarski fakultet Sveu~ili{ta u Zagrebu i Zavod za {umarske tehnike i tehnologije u bolonjskom procesu Reforma visoko{kolskoga obrazovnoga sustava potaknuta je na Ministarskoj konferenciji u Bolonji 1999. godine dono{enjem tzv. Bolonjske deklaracije, koja je razra|ivana na kasnijim konferencijama ministara Europske unije, koje se odr`avaju svake dvije godine. Bolonjska je deklaracija temeljni dokument za reformu visokoobrazovnoga sustava u Europskom prostoru visokoga obrazovanja (EHEA). Potpisali su je ministri obrazovanja 29 europskih zemalja na Ministarskoj konferenciji u Bolonji 19. lipnja 1999. Hrvatska je prihvatila i potpisala dokument 2001. na Ministarskoj konferenciji u Pragu. Time se Hrvatska opredijelila za europski visoko{kolski obrazovni sustav preddiplomskoga i diplomskoga studija, a prihva}anjem preporuka Berlinske ministarske konferencije iz 2003. godine o doktorskom studiju zaokru`en je trostupanjski ciklus visokoga obrazovanja – preddiplomski,

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Faculty of Forestry, University of Zagreb and Department of Forest Engineering ... (123–136)

diplomski i doktorski. Visoko{kolski se obrazovni sustav reformira radi svrhovitijega obrazovanja i br`ega uklju~ivanja kompetentnih i vje{tih mladih stru~njaka u gospodarske tokove i stvaranje vlastite karijere. Pri tome se u prvi plan stavljaju kriteriji izvrsnosti, kompetentnosti i pokretljivosti. Ministri iz 33 europske zemlje 2003. godine u Berlinu utvr|uju prioritete za ubrzano stvaranje ja~ih veza izme|u Europskoga prostora visokoga obrazovanja (EHEA) i Europskoga istra`iva~koga prostora (ERA) te nu`nost uspostave tre}ega ciklusa visokoga obrazovanja (doktorskoga studija) u okviru Bolonjskoga procesa. Pri tome su kao najva`niji prioriteti istaknuti: interdisciplinarnost, sustavan pristup osiguranju i unapre|ivanju kakvo}e visokoga obrazovanja, mobilnost studenata i istra`iva~a te povezivanje u mre`e izvrsnosti. Bolonjska reforma visokoobrazovnoga sustava u Hrvatskoj na dr`avnoj je razini odre|ena Zakonom o znanstvenoj djelatnosti i visokom obrazovanju iz 2003. godine te usmjerena podzakonskim aktima i drugim dokumentima Sveu~ili{ta. U reformu doktorskih studija uklju~uje se Nacionalna zaklada za znanost, visoko {kolstvo i tehnologijski razvoj Republike Hrvatske, koja donosi deset temeljnih na~ela za organizaciju doktorskih studija. Nacionalno vije}e za visoko obrazovanje Republike Hrvatske 14. srpnja 2006. donosi Na~ela za uspostavu poslijediplomskih doktorskih studija koja sadr`e Op}a na~ela, Na~ela studiranja i Organizacijska i financijska na~ela. [umarski fakultet u Zagrebu najstarija je visokoobrazovna strukovna ustanova jugoisto~ne Europe, koja korijene vu~e iz Visokoga gospodarsko-{umarskoga u~ili{ta osnovanoga 1860. godine u Kri`evcima i [umarske akademije utemeljene 1898. u Zagrebu. Od 1920. do 1960. godine djeluje u sklopu Poljoprivredno-{umarskoga fakulteta Sveu~ili{ta u Zagrebu, a potom kao samostalni fakultet u okviru Zagreba~koga sveu~ili{ta. Do danas je na Fakultetu diplomiralo 4580 studenata {umarstva i 1647 studenata drvne tehnologije. Akademske titule magistra znanosti i magistra specijalista stekla su 343 studenta, od kojih 246 u znanstvenom polju {umarstvo, a 97 u znanstvenom polju drvna tehnologija. Obranjeno je ukupno 190 doktorata, 139 u znanstvenom polju {umarstvo i 51 u znanstvenom polju drvna tehnologija. Slijede}i platforme, upute i zacrtane ciljeve te vlastita i strana iskustva, na [umarskom je fakultetu uspje{no provedena prva faza reforme obrazovnoga sustava. Prihva}en je trostupanjski obrazovni sustav te su izra|eni obrazovni programi za preddiplomske, diplomske i poslijediplomske studije po shemi 3 + 2 + 3 (2) odnosno 180 + 120 + 180 (120) ECTS bodova. Uspostavljena su tri preddiplomska studija: [umarstvo, Urbano {umarstvo i Drvna tehnologija, po kojim se programima obrazuju ve} dvije generacije studenata. Razvijeni su programi diplomskih studija [umarstvo i Urbano {umarstvo, za{tita prirode i okoli{a te programi Drvnotehnolo{ki procesi i Oblikovanje proizvoda od drva. Diplomski studij [umarstvo ima dva smjera: Uzgajanje i ure|ivanje {uma s lovnim gospodarenjem i Tehnike, tehnologije i menad`ment u {umarstvu. Nadalje, razvijen je pobolj{ani prijedlog doktorskoga studija [umarstvo s tri smjera (Uzgajanje {uma i lovno gospodarenje,Tehnike, tehnologije i menad`ment u {umarstvu te Urbano {umarstvo, za{tita prirode, ure|ivanje i za{tita {uma) te program doktorskoga studija Drvna tehnologija. Specijalisti~ki poslijediplomski studiji razra|eni su u deset programa i zami{ljeni su kao sastavnica cjelo`ivotnoga obrazovanja stru~njaka iz prakse. [umarskomu je in`enjerstvu poklonjena zna~ajna pa`nja kreiranjem obrazovnih programa, ~iji su nositelji ~lanovi Zavoda za {umarske tehnike i tehnologije. Tako je ostvaren poseban obrazovni program u diplomskom studiju [umarstvo, koji nosi naslov [umarstvo – smjer: tehnike, tehnologije i menad`ment u {umarstvu. U okviru doktorskoga studija [umarstvo Zavod je razvio program smjera doktorskoga studija pod nazivom Tehnike, tehnologije i menad`ment u {umarstvu. Na Zavodu su razvijena tri prijedloga programa specijalisti~kih studija, od kojih su programi [umarske tehnike i tehnologije i [umske prometnice pro{li evaluaciju, a tre}i, Menad`ment i poduzetni{tvo u {umarstu, nalazi se u postupku predlaganja. Programi svih stupnjeva obrazovanja na [umarskom fakultetu u vremenu sada{njem i budu}em moraju se stalno pobolj{avati i na taj na~in pribli`avati zadanim ciljevima reforme, tj. da visokoobrazovne institucije brzo, uspje{no i kvalitetno obrazuju mlade stru~njake, kompetentne nositelje razvoja struke i ekonomije na doma}im i europskim prostorima. Klju~ne rije~i: [umarski fakultet u Zagrebu, reforma visokoobrazovnoga sustava

Author’s address – Autorova adresa:

Received (Primljeno): January 18, 2007 Accepted (Prihva}eno): March 22, 2007

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Prof. Ante P. B. Krpan, PhD. e-mail: krpan@sumfak.hr Forestry Faculty of Zagreb University Department of Forest Engineering Sveto{imunska 25 HR-10 000 Zagreb CROATIA Croatian Journal of Forest Engineering 28(2007)1


CROJFE - Volume 28, Issue 1