Author/Authors :
ZAWAL، ANDRZEJ نويسنده Department of Invertebrate Zoology and Limnology, Szczecin University, W?ska 13 PO-71-415 Szczecin, Poland, , , Kowalik، Witold نويسنده University of Life Sciences in Lublin, Department of Zoology, Animal Ecology and Wildlife Management, Akademicka 13, 20-033 Lublin, Poland, ,
Abstract :
The collections of water mites (Hydrachnidia) from the years 1973 and 1974 of two upland rivers – the Bia?a and Czarna ?ada (south-eastern Poland) were elaborated. Among 1,178 individuals, 43 species were distinguished: 34 species in the River Bia?a ?ada and 27 in the River Czarna ?ada. Rheophiles and rheobionts were dominating. Some mountain species, rare in the upland areas also occurred. Seasonal changes of numbers and clear negative impact of water pollution and hydrotechnical works on water mites were found in the studied rivers, too.
