of the data format was fixed in 2008. Translation of the main (mire) worksheet is presented in Annex I. For the inventory three field worksheets were used: one for (open) mires and others for grasslands and forests. In all worksheets the following characters were examined and respective assessments given: • Estonian vegetation habitat site type (according to Paal 1997); • Natura 2000 habitat type; • state of shrub and tree layers, their main species; • obvious changes in field layer; • human impact (drainage, mowing, grazing, burning, other impacts); • nature conservation values (plant community state, floristical and aesthetical value, other values – hydrological, faunistical, recreative, didactic, etc.); • representativity of habitat; • global assessment (importance for nature conservation). According to grassland/forest worksheets supplementary data were recorded concerning details and history of management, characters of communities structure, etc. On the other side of the worksheets the standard registration list of the Estonian flora was printed for recording plant species and their abundance values. If possible, composition of (ornitho)fauna was also minuted. To determine the sites for field work, and for the later use in GIS, a convenient map was needed. Of several maps for Estonia that exist in different scales and with various levels of accuracy, the basic map was chosen for the study. It is in 1:20,000 scale and covers the whole of the Estonian territory. The basic map is made on the ground of orthophotos, has good accuracy and well defined borders of landscape units. The map also has a digital version and has been constantly renewed. Orthophotos have been used through public Web Map Service (WMS) offered by the Estonian Land Board.
7.6 Field work 2009-2010 The initial target for field work was set to 8,000 mires. However, in the course of the project, the number of the inspected mires reached 13,901 as the number of small mires depicted on the new basic map turned out to be larger than identified on older maps. Of these, 4,175 areas were inspected in 2009 and 9,726 mires in 2010. Field work was started in mid-June 2009 when vegetation was sufficiently developed for determination of species. Usually a team consisted of 1-2 experts including scholars or nature conservation specialists, and students. During the inventory all areas on the map marked with open or treed mire symbol were visited. Field work periods were June–November 2009 and June–November 2010. In the beginning of both field work periods, an instruction day for field experts was arranged. In May 2010, a special training day concerning mire vegetation was carried out. However, to unify the results of inventories and to diminish the quality control, a longer period training would have been beneficial. The following experts participated in the field work: Ardo Aamer, Maire Akkermann, Ants Animägi, Madis Avi, Sirje Azarov, Tarmo Evestus, Eli Fremstad, Tiit Hallikma, Katre Halliko, Raili Hansen, Reeli Hansen, Indrek Hiiesalu, Toomas Hirse, Talvi Jusilo, Meeli Jänes, Johanna-Iisebel Järvelill, Ülle Jõgar, Helle Kaasik, ESTONIAN MIRES: INVENTORY OF HABITATS
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