Spatial variation in assemblages of Odonata (Insecta) within habitat gradients in large, pristine peat bogs in Belarus

Abstract

The variation in environmental conditions in peat bogs can be expressed by odonate assemblage composition among habitats or by differences in species richness, abundance and diversity among study sites in a regional context. The adult Odonata of large, pristine peat bogs in Belarus were examined. Adult Odonata were counted along fixed transects in main peat bog habitats under favorable weather conditions. The odonate diversity showed clear differences, affected by distance to the water body, wind speed, and bog water level. The highest diversity was recorded along lakeshores. This study detected distinct odonate assemblage variations among habitats such as lagg zones, lakeshores and hollows. The large areas occupied by pine bogs and open bogs had a very similar species composition and lower diversity. On the other hand, the Shannon diversity index (H′ = 1.433–2.295) and Pielou’s evenness index (J’ = 0.468–0.507) values were relatively high compared to those of terrestrial insects. The main differences among adult odonate assemblages were driven by cold-adapted, highly specialized species such as Leucorrhinia albifrons, Leucorrhinia dubia, Sympetrum danae and two abundant generalist species such as Sympetrum sanguineum and Sympetrum vulgatum. Peat bog specialists are among the most rapidly declining insects and, therefore, relatively intact Belarusian peat bogs are refuges for many threatened species and have considerable conservation potential.