Tudu õpperaja infotahvlid - ENG

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DEAR HIKER! You've reached the Järvesoo educational Tudu Tallinn trail of Tudusoo Nature Reserve, also known E S TO N I A as the Tudu educational trail. The trail is Tartu less than a kilometre long, but is accesLATVIA sible by wheelchair. A barrier by the side CABIN of the trail is helpful to the visually impaired. There are a total of nine post-mounLAKE ted information boards along the trail. TUDU The accompanying texts contain information about the mire system of Tudu, as well as explain the necessity of restoring JÄRVESOO MIRE mires. Descriptions of nature are intertwined with bits of local history. In addition to textual information, each information board features drawings, and a so-called field guide with photos of the local biota is available. At the end of the trail, one can enjoy a view of Lake Tudu and cook over a campfire. Shelter can be sought in a cabin equipped with a stove when it's rainy or one is overcome with sleep. Should any our dear guests wish to cover more distance, the 6-kilometre Seljamäe hiking trail is just nearby. The origins of this nature reserve date back to 1976 when the then authorities decided to establish a bear reservation southwest of Tudu. Since then, the nature reserve has been considerably expanded, and Tudusoo Nature Reserve was established in 2006. It's a 20-kilometre long and 5-kilometre wide area of mire landscapes and forests. Lake Tudu, a bog lake found in the middle of the nature reserve, is a favourite resting place for migrating birds. This makes a large part of Tudusoo Nature Reserve a bird area of international importance, or an IBA area (Important Bird Area), and a designated If you discover Natura 2000 site. Natura 2000 is a Europe-wide that nature has been harmed, network of nature conservation areas. dial The LIFE programme of the European Union and the Estonian Environmental Investment Centre provided the funds for the completion of the trail.

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Text by Piret Pungas-Kohv, Marko Kohv Edited by the team of project “Restoration and Preservation of Mires” Translation into English by Tõnu Soots Illustrations and design by Triinu Sarv Bibliography available at soo.elfond.ee

RUSSIA

Maa-amet 2020


DAMS HELP BREATHE LIFE INTO MIRES Despite their long-term, diverse conservation status, the local mires, too, have been damaged by the establishment of drainage ditches, as is the case in many places all around Estonia. At first, drier land was needed to turn it into farmland. Then it was discovered that peat, which grows in bogs, makes suitable bedding for animals, and in some cases it was also used for heating. In the middle of the 20th century, those Peat dam. Photo: Marko Kohv calling the shots thought that mires could perhaps be turned into forest land. It must be admitted that the concept of forest growth envisaged back then has started to become reality in some measure. A comparison of aerial photographs from half a century ago and now reveals that former areas of open bog are now covered with forest. The more forested land there is, the quicker the trees help drain the land as their crowns facilitate water evaporation. This, in turn, further accelerates mire drainage. Gradually, plant and animal species that are characteristic of mires disappear, peat begins to decompose, the risk of fire increases, etc. In order to mitigate the situation, it has been decided that drained mires should be restored. The first step has been to identify suitable protected areas. Next, a computerised model has been created based on the relief of the respective areas to get an idea of how the natural water regime might have once been in these areas. Calculations have been made based on a theoretical model to identify specific spots in ditches that need to be dammed in order to restore the water regime of these specific areas. When a dam is constructed, its site is cleared of plants and roots Soil dams disperse water into the landscape between ditches. beforehand. A so-called peat filling is then fixed into place. Peat fillings can be compared to tooth fillings, only they're larger. These fillings are also fitted with what we call wings so that water could be redirected from ditches and it would evenly spread into the surrounding mire landscape. Some smaller Overflow dams raise the water level in ditches. ditches are simply filled Some water flows over the dam up in their entirety. and onwards in the ditch.

Text by Piret Pungas-Kohv, Marko Kohv Edited by the team of project “Restoration and Preservation of Mires” Translation into English by Tõnu Soots Illustrations and design by Triinu Sarv Bibliography available at soo.elfond.ee


WHAT BECOMES OF FORESTS WHEN MIRES ARE RESTORED? When approaching this information post, you probably noticed the ground rising just a bit. This is a marginal slope, which is where a transition mire becomes a raised bog, and the boardwalk leads closer to the roof of the bog. Perhaps you also noticed the openness before you reached the marginal slope? Prior to deforestation, the area was covered with young pines – a result of drainage ditches. One can even see straighttrunked pines around this information post. Only a few are crooked and look considerably older. In order for a mire to have a chance of recovery, we must first find a way to make it retain water. Once the Greyhen amount and locations of dams are in place, Фото: Марко Кохв we must turn our attention to trees if the situation so demands, because tree crowns facilitate the process of water evaporation, which may render the establishment of dams useless. After conducting fieldwork and carefully comparing maps and aerial photographs of different times, a decision is made on where to fell trees. The objective is to create favourable conditions for the recovery of these areas, which were once open bogs. Mire vegetation absorbs carbon dioxide from the atmosphere during photosynthesis. The difference with all other plant communities is that healthy mires sequester carbon for thousands of years as excessive moisture keeps plants from decomposing completely. The plant matter that is thus accumulated is called peat. In addition, special, wonderful landscapes covered with sphagnum mosses are (re)created. These landscapes are a great habitat for bird and animal species that cannot live elsewhere. Игра вприпрыжку Фото: Элизе Кара

Text by Piret Pungas-Kohv, Marko Kohv Edited by the team of project “Restoration and Preservation of Mires” Translation into English by Tõnu Soots Illustrations and design by Triinu Sarv Bibliography available at soo.elfond.ee


WIND-SWEPT FOREST

You've probably noticed black tree roots in the forest surrounding you. Kalevipoeg, the protagonist in the Estonian national epic, and his heroic deeds are not to be blamed for this. What you see is the outcome of a twister, or tornado, which in the summer of 2001 resulted in many windfallen trees in this area. The route of the tornado is clearly visible as a 100-kilometre-long trail, since the tornado left a wide and treeless corridor in its wake. In order for a tornado to form, we need hot air that wants to rise up, as it's thinner and lighter – like the air above a bonfire. And if there's cooler air in the higher air layers that wants to descend towards the ground, being denser, this rapid movement of air creates a vortex. Such circular dances in the air may wreak havoc in the human world, but at the same time, many small organisms find food or a new home when these occur. In addition to wind, forests are sometimes pestered by fire. Fires often start because somebody has thrown an empty glass bottle on the forest floor, which may focus sunrays at specific angles. The rise in temperature resulting from beams that are thus created acts like a match to dry moss. Sometimes campfires get out of hand, or fires are lit when it's extremely windy or dry. Sometimes lightning strikes a tree. There are many reasons. In any case, one should remember that rubbish shouldn't be dumped in forests or mires. If you see a forest fire, dial 112.

Windfallen trees. Photos: Marko Kohv Text by Piret Pungas-Kohv, Marko Kohv Edited by the team of project “Restoration and Preservation of Mires” Translation into English by Tõnu Soots Illustrations and design by Triinu Sarv Bibliography available at soo.elfond.ee


BOG LAKES, BOG POOLS, BOG HOLLOWS You've reached the top of the bog dome, where bog hollows and bog pools nest alongside quite a few animal and bird species. Both of these small bodies of water have formed due to the flat surface of the bog roof, which inhibits any water from running off properly. As a result, small bodies of water gradually form, and water introduces extra oxygen into them. The latter accelerates the decomposition of plant m a t te r, a n d a b o g h o l l ow i s fo r m e d . Furthermore, bodies of water in mires facilitate water evaporation, making the process faster compared to other places in mires. Hence, mires selfregulate their hydrological cycle.

Bog pool. Photo: Marko Kohv

So, bog hollows are muddy "pockets of water" that are covered with a brownish or bright green layer of moss. In general, bog hollows are not solid enough to support a man. Bog hollows should not be trodden on as one may fall in. However, should you find yourself in a bog hollow, your rubber boots filling with water, you must quickly lie flat on your belly. By doing so, you distribute your body weight more evenly on the bog surface–you stop sinking deeper and can slowly start to roll yourself out of the hollow. Often there are bog pools near bog hollows. Bog pools are small murky bodies of water. Bog pools sometimes form as the next developmental stage of a bog hollow when the layer of sphagnum mosses decomposes in a bog and brownish bog water can be seen all year round. Slightly higher and drier areas then form between bog pools and bog hollows. These are called bog beds. Like in a kitchen garden, only instead of cabbages and carrots, gnarled pine trees grow in mires.

Text by Piret Pungas-Kohv, Marko Kohv Edited by the team of project “Restoration and Preservation of Mires” Translation into English by Tõnu Soots Illustrations and design by Triinu Sarv Bibliography available at soo.elfond.ee


THE BEST-KNOWN DITCH IN THE MIRE SYSTEM OF TUDU A few tens of metres separate you from sights of the bog lake of Tudu. Lake Tudu has been an endorheic lake for hundreds of years. However, a ditch was dug from the lake towards the settlement of Tudu in the 1850s. More specifically, the glass factory of Tudu, said to have been established by Walter, a local landlord, was situated slightly to the south of the settlement. The location still bears the name Vabriku (vabrik meaning 'factory') because of the glass factory. Farmers transported the bottles that were manufactured there to the market of Saint Petersburg. Johan Runge was the manager of the glass factory. In around 1880, Runge left Tudu and started to manage the glass factory of Järvakandi. Danish glassblowers moved from Tudu to Järvakandi with him. We may assume that the glass factory badly needed a source of water in order to keep its glass moulds immersed in water at all times, preventing them from drying up and catching fire when they came into contact with molten glass. It's also been suggested that there was a sawmill near the factory, which needed water as well. The ditch may have helped raft logs, too. Another strange fact is that a blueprint from 1884 features the ditch as Master's Ditch, but maps from the beginning of the 20th century no longer show the ditch. However, the ditch reappears on maps dating from the 1950s. According to Juhan Lepasaar, a lieutenant Part was active in the region, founding a peat community with the aim of cutting peat from the banks of the ditch with spades. He also had the ditch dredged. However, according to other locals, the ditch has never been dredged. It seems impossible to get to the bottom of the matter.

Photo: Marko Kohv Text by Piret Pungas-Kohv, Marko Kohv Edited by the team of project “Restoration and Preservation of Mires” Translation into English by Tõnu Soots Illustrations and design by Triinu Sarv Bibliography available at soo.elfond.ee


THE STORY OF THIS CABIN And you've made it to the cabin, which was built as far back as the mid1990s. It was initially designed for local goose hunters who preferred to stay by the lake until morning came, chatting away, rather than return home before dark. A few years later, a sauna and boardwalk were completed. However, the site quickly garnered renown, and not all guests conducted themselves in a civil manner and had good intentions. There was also a fire in the sauna. The sauna was relocated to the yard of the Hunter's House near the settlement of Tudu, where it still provides relief to hunters. The cabin is maintained by the State Forest Management Centre. One of the objectives of an extensive mire restoration project initiated in 2015 was to repair the boardwalk. Since the trail was reconstructed as a trail for the disabled, people in a wheelchair can also independently access the lake to enjoy the view or cook over a campfire. Hopefully, you'll also find a hikers' journal on the table in the cabin. In the first years after the construction of the cabin, these journals persisted for quite some time, awaiting hikers' entries. Yet, as years went by, one journal after another was engulfed by flames. Our hope is that the cabin's guests have rediscovered their appetite for writing. May your quill be swift and sharp!

Text by Piret Pungas-Kohv, Marko Kohv Edited by the team of project “Restoration and Preservation of Mires” Translation into English by Tõnu Soots Illustrations and design by Triinu Sarv Bibliography available at soo.elfond.ee


NATURE AROUND LAKE TUDU Lake Tudu formed after the last Ice Age. Over hundreds of years, the landscape around the lake turned into a mire. The bottom of the body of water reveals that it's not a huge bog pool. While the bottom of a bog pool is peaty, i.e. made up of only plant remains, there are mineral sediments under the layer of peaty mud at the bottom of a bog lake. In like manner, there's about a metre of peat mud at the bottom of Lake Tudu, underneath which we find sand that was deposited there as far back as the end of the last Ice Age. Lake Tudu is a landlocked bog lake. It has no natural stream or rivulet outlets. The so-called Tagajõgi (or Back River) that runs behind the cabin and below the educational trail is actually a ditch that was dug long ago. Following recent mire restoration operations, it is now dammed. Some decades ago, the ditch was deeper, enabling water from the lake to flow out. The tree stubs you see peeking out from the peaty bank are testament to the fact that the ditch caused the lake's water level to drop by a metre. The lake is a few metres deep at the edges, but the depth in the middle of the lake is up to five metres. The surface area of the lake is about five hectares. There's not a lot of life in the body of water. According to legend, a big bony pike dwells in the lake. Locals have said that young pikes have been introduced into the lake, yet no anglers can be seen. When the weather's warm, one can go for a swim in the lake. There's a pontoon bridge for that purpose.

Lake Tudu Photo: Marko Kohv Text by Piret Pungas-Kohv, Marko Kohv Edited by the team of project “Restoration and Preservation of Mires” Translation into English by Tõnu Soots Illustrations and design by Triinu Sarv Bibliography available at soo.elfond.ee

Bean goose (Anser fabalis) Photo: Arne Ader


LAKE TUDU AND CULTURE

In previous times, the lake has also been called Lake Suigu or Lake Muda. Currently, the bog lake is called Lake Tudu (in Estonian, tuduma is a cute synonym for 'to sleep'). As for the origin of Lake Tudu, the folklore goes as follows, according to Mall Hiiemäe. In earlier times, there used to be a lake in the middle of a sacred grove by the village of Tudu. One summer afternoon, a gypsy woman's sorcery made the spirits of two young women appear from the grove. The spirits, said to have been dressed in white, stepped into the lake and burst into tears. As they were doing this, water began to vanish from the lake, until the lake was completely dry, but while the lake was running dry, another lake appeared in the middle of the mire. This is how undines carried the water from the village to Järvesoo (or Lake Mire). Another story again takes us to the settlement of Tudu, but instead of a gypsy woman, a Finnish crone uttered a spell which made a sprite relocate from the sacred grove of Tudu to the landlocked lake of Tudu. The sprite punished the Finnish crone by taking her voice. Currently, it seems, pikes and sprites live peacefully side by side. Who knows, if one is respectful, sits quietly and waits, they might just show themselves. Those who are impatient should perhaps have a chat with the locals to inquire about possibly participating in the Tudu Triathlon, which is one of the oldest events of its kind in Estonia, having taken place here since 1988 without interruption. This is where it starts! Lake Tudu Photo: Marko Kohv Text by Piret Pungas-Kohv, Marko Kohv Edited by the team of project “Restoration and Preservation of Mires” Translation into English by Tõnu Soots Illustrations and design by Triinu Sarv Bibliography available at soo.elfond.ee