Allogenic succession Biotic homogenization Habitat quality Mine subsidence Odonata Man-made habitats

We compared diversity of dragonflies in three main freshwater habitat types occurring in Upper Silesia. We used multivariate methods and diversity indices for a general analysis, comprising both species richness and the species composition of assemblages. We recorded 50 species in mine subsidence pools from the total of 54 sampled species. These included a high proportion of habitat specialists. We emphasize that secondary habitats should not a priori be regarded as ecological traps. These habitats significantly outweigh ponds in species richness and proportion of habitat specialists. The conservation potential of specific secondary habitats lies in the fact that these habitats can substitute for very rare natural wetlands often restricted to higher elevations. We assume that high diversity in this type of secondary habitats is not random, but rather that it depends on environmental heterogeneity caused by a specific allogenic succession process occurring as a direct consequence of mining.

We compared diversity of dragon?ies in three main freshwater habitat types occurring in Upper Silesia. We used multivariate methods and diversity indices for a general analysis, comprising both species richness and the species composition of assemblages. We recorded 50 species in mine subsidence pools from the total of 54 sampled species. These included a high proportion of habitat specialists. We emphasize that secondary habitats should not a priori be regarded as ecological traps. These habitats signi?cantly outweigh ponds in species richness and proportion of habitat specialists. The conservation potential of speci?c secondary habitats lies in the fact that these habitats can substitute for very rare natural wetlands often restricted to higher elevations. We assume that high diversity in this type of secondary habitats is not random, but rather that it depends on environmental heterogeneity caused by a speci?c allogenic succession process occurring as a direct consequence of mining.