Earthworms (Oligochaeta, Lumbricidae) in the Tundra of Eastern Europe

详细

It has been established that three earthworm species inhabit tundra landscapes of Eastern Europe: the Eastern European–Siberian Eisenia n. nordenskioldi, cosmopolitan Lumbricus rubellus (sporadic occurrences near the forest edge), and cosmopolitan Dendrobaena octaedra. In the Palaearctic zonal tundra, D. octaedra does not occur east of Tazovskii Peninsula, while E. n. nordenskioldi was not found west of Pechora Bay. The two species coexist in the Arctic only in Nenets and Yamalo-Nenets Autonomous okrugs. New earthworm records in the northern part of Eastern Europe have been reported. The significant habitat plasticity of D. octaedra and E. n. nordenskioldi in tundra landscapes is demonstrated. It is found that the cold-resistant soil-litter E. n. nordenskioldi prefers open habitats (dwarf shrub tundras, meadows, and marshes), while the less cold-tolerant (in the worm phase) litter D. octaedra is more abundant under the shrub or crooked forest canopy, possibly, because of the milder wintering conditions there (i.e., the presence of leaf litter and snow retention). It is suggested that the habitat area of E. n. nordenskioldi in Eastern Europe was much larger during the last glacial epoch.