Tudusoo Nature Conservation Area

Tudusoo Nature Conservation Area (NCA) is located in northeastern Estonia, on the eastern slope of Pandivere uplands. The Pandivere Upland is the highest bedrock upland in Estonia. Its bedrock is represented by Middle and Upper Ordovician and Lower Silurian limestones. The Quaternary cover of the upland is only a few meters thick and is composed of calcareous clayey till.

NCA consists of several mires which are located on the eastern slope of upland, in dells formed due to glacial activities. Formation of the wetlands is a result of paludification of shallow waterbodies and clay soils. The northern part consists of fens, rich in minerotrophic springs, the rest of the area is covered by bogs. In the middle of the area has remained relict lake, covering 25 ha, depth 2.5 to 5 m.

Tudusoo mire. Infographics: Marko Kohv; Maps: Land Board.

In Tudusoo NCA restoration work is planned in 3 mires:

1. Tudusoo mire was inventoried in 2001 by ELF mire inventory covering 305.50 ha of mire habitats (Paal and Leibak 2011). Following classification of the Estonian vegetation site types (extract from Paal, 1997) the area is determined as mixotrophic (transitional) grass mire site type, treed and treeless hummock bog site type, pool-ridge bog site type. In addition, 16 ha are determined as mixotrophic (transitional) bog forest site type and mixotrophic (transitional) grass mire site type.
2. Anisoo mire consists of different subparts: three areas (48.69 ha 36.30, 27.61 ha and 19.57 ha) are classified as treed hummock bog site type.
3. Luussaare (Luusaare) mire (inventoried in 2007) covers 261.03 ha. The area is classified as treed and treeless hummock bog site type and treed and treeless hollow-ridge bog site type.

There is very intense forest drainage network all around and in some parts even crossing core 7110*, 7050 and other habitats. Former wet forests (91D0* and others) that surrounded open mires are by now almost fully degraded. Closure of drainage network and reversal of secondary impacts will stop ongoing negative effect to Natura 2000 habitats and allow slow recovery of surrounding wet forests like 91D0*.

Literature:

• Paal, J. 1997. Eesti taimkatte kasvukohatüüpide klassifikatsioon. Eesti keskkonnaministeerium, ÜRO keskkonnaprogramm. Tallinn. /in Estonian/
• Paal, J., Leibak, E. 2011. Estonian Mires: Inventory of Habitats. Tartu.