Leech (Hirudinea) communities of post-exploitation water bodies in industrial region (Upper Silesia, Poland)

The investigations were carried out in post-exploitation water bodies (subsidence pools, sand- and gravel pits) situated in urbanised and over-industrialised region of Upper Silesia. The least diversified leech (Hirudinea) communities occurred in subsidence pools, because of the very high concentration of chlorides, sulphates and phosphates in their water, which is moreover very hard and of high BOD5 value. In other kinds of studied water bodies greater leech species diversity was observed. Most of the species found in studied water bodies occur commonly in various freshwater habitats, what may point out the lack of peculiarity of leech communities in these unnatural conditions.