Enchytraeid communities in successional habitats (from meadow to forest)

The study was conducted in two successional series: natural on mesotrophic soils (a meadow, two birch woods and a mixed coniferous forest), and human-made on sandy soils (old field, birch plantation and pine forest). In both these series species richness and diversity of enchytraeid communities decreased with advancing succession. In the first two successional stages, enchytraeid communities showed a high degree of similarity (the meadow and 30-year-old birch thicket, ore the old field and 10-year-old birch plantation). Variation in soil in the same plant communities cause differences in animal communities. The abundance of enchytraeids varied from 14 to 51 × 10³ m⁻² individuals. In the majority of habitats C. sphagnetorum was the dominant species. Soil pH showed a positive correlation with species diversity and negative with number of C. sphagnetorum. The body size of this species was small at low pH (presumably as a result of frequent reproduction). It is suggested that the way of reproduction of the dominant species could confer a competitive advantage, thereby accounting for the simplification of enchytraeid communities in later stages of succession.