Agusalu Nature Conservation Area, Feodorisoo Mire

Feodori soo Kaart: Maa-amet

Feodorisoo Mire

Agusalu Nature Reserve comprehends mainly Agusalu mire system and surrounding forests. Big and complex system consists of smaller mires as Riiska, Heinsoo, Repna and Feodorisoo mires, and Võhmakivi and Ristikivi bogs. The nature reserve is situated in the southern part of the largest mire system – Puhatu – of Estonia. The mire formed following the overgrowth of the lake area between sand dunes of the Primeval Peipsi Lake and in some parts due to paludification of mineral ground. There are two relic lakes in the reserve, which former constituted a common waterbody. Agusalu mire is very peculiar, since it has formed between a sandy range of hills – kriivas. Therefore, the general appearance of the landscape is striped – narrow islands in an east-west direction are covered by heathy pine forest, which alternate with wet bogs. Treeless bogs are often surrounded by transitional wet zones or very wet and hardly penetrable quagging mires with bog bean and cotton grass. These small mires between kriivas have given a unique opportunity to study mire development from the lower stages (fen as a first one) to the highest (bog as the last one), including the transitional stage – swamp or transitional mire. This heterogeneous and rich area is by relevant experts meant to be valuable in terms of diversity of landscapes and habitat types forming a complex being totally intact.

Bog woodland surrounding mires and bog habitats provide breeding places for many Habitats Directive Annex II priority species as Ursus arctos and very rare Pteromus volans as well as for Canis lupus, Castor fiber and Lynx lynx. The representatives of bird fauna are Bird Directive Annex I species as Tetrao urogallus, Tetrao tetrix, Grus grus, Ciconia nigra, Falco peregrinus, Haliaeetus albicilla, Tringa glareola, Strix uralensis, Aquila chrysaetos and Lagopus lagopus. The latter is also a target specie for the restoration activities in Feodorisoo mire in Agusalu NCA restoration site.

Feodorisoo 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 treed hummock bog site type, treed hollow-ridge bog site type,  pool-ridge bog site type, treed and treeless mixotrophic (transitional) grass mire site type.

In 2012, initial restoration plan for the area was completed by ELF. Within field work drainage network was mapped and initial estimation of drainage impact was given. As the area was burned in 2006, leaving most of tree layer dead, it provides suitable conditions for further restoration actions. As trees were burned then their function to reduce water level was eliminated and afterwards the water level has increased. Still, as the drainage network is active and working, and in order to secure favourable conditions for the habitats, there is a need for concrete restoration actions.

In Feodorisoo, large drainage ditches crossing entire core 7110* habitat. Ditches are relatively distant to each other but influence almost entire 7110* habitat causing overgrowth by pine forest. Bog forests at the NE part of the project area are also strongly influenced by drainage systems, leading to loss of Sphagnum cover, unnaturally dense forest and intrusion of Picea abies.