Ohepalu Nature Conservation Area (NCA) is situated in north Estonia, being uniting link for two big conservation areas as Põhja-Kõrvemaa Landscape Reserve and Lahemaa National Park. The area is a complex of raised bogs, fens, transitional mires, forest and many small lakes. The Ohepalu NCA covers Ohepalu bog, Tuksmani mire and includes several lakes as Ohepalu Suurjärv Lake, Väikejärv Lake and Kaanjärv Lake. Valgejõgi River borders the area from south side. Bogs belong to the division of big peatlands of north Estonian highland; forests are situated between Kõrvemaa and Järva-Kurista forest regions on the northern part of intermediate Estonia.
Ohepalu NCA is the area of heterogeneous natural landscape, where the forests interchange with overgrown pastures and grasslands. Deciduous mixed forests dominate over rest of forest communities. Ohepalu Suurjärv Lake is profoundly surveyed and found to be the most characteristic representative of shallow dystrophic lake in Estonia having big value from landscape and scientific viewpoint. Habitats vary from forest habitats as Western taiga, Fennoscandian herb-rich forests with Picea abies, Fennoscandian deciduous swamp woods and Bog woodland to wetland and water habitats as Active raised bogs, Transitional mires and quaking bogs and Natural dystrophic lakes and ponds. Ohepalu-Udriku Mire complex is an important roosting place for migrating Bird Directive Annex I species Grus grus in autumn and regular breeding site for Ciconia nigra, Gavia arctica, Tringa glareola, Podiceps auritus and Aquila chrysaetos. The references about breeding Gavia stellata originate from the middle of last century. The area is growing site for several rare and protected orchids and other plants of II or III protection categories as Dactylorhiza cruenta, Lycopodium clavatum, Ophrys insectifera, Daphne mezereum, Goodyera repens, Platanthera bifolia, Epipactic palustris, Listera ovata, Epipactic atrorubens and for Habitats Directive Annex II species Cypripedium calceolus. Ohepalu NCA provides habitats for Habitats Directive Annex II species as Canis lupus, Ursus arctos and Castor fiber.
In Ohepalu NCA, mire inventory was implemented by ELF in 2009 and 192.36 ha of mire habitats were mapped (Paal and Leibak 2011). Following classification of the Estonian vegetation site types (extract from Paal, 1997) the area is determined as hummock bog site type, hollow-ridge bog site type, pool-ridge bog site type.
7110* habitats are negatively influenced by water loss through Ohepalu lake, that has currently artificial and lowered outflow ditch. Proposed closure would remove this ongoing negative influence to priority habitat 7110*. Western part of the project area is influenced by forest drainage that has caused loss of former mosaic of open mires, wet forests and mineral islands.
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