The impact of human activity on the water mite fauna (Acari, Hydrachnidia) of the ‘Lasy Janowskie’ Landscape Park (South-Eastern Poland)

Abstract

Water mites of the ‘Easy Janowskie’ Landscape Park (South-Eastern Poland) were investigated, with the aim of documenting the qualitative and quantitative structure of coenoses in various habitats in the Park. Particular attention was paid to the impact of human activity on the Hydrachnidia fauna in the surface waters of the study area. The main types of human impact in running waters of the Park were: 1) river-bed regulation (causing a decrease in the species number, mainly in rheobionts and rheophiles), 2) discharge of fish pond waters into the river (causing an increase in the number of species and specimens, a domination of stagnobionts and a reduction of rheobionts and rheophiles, and a disturbance of population dynamics), 3) water pollution (causing the reduction of numbers of species and specimens). In the fish ponds exposed to human activity (regular draining, pond bottom ploughing, fertilization, water pollution by fish food), the water mite fauna was sparser and less diversified than in big shallow lake type ponds. The water mite fauna of transitional waters (canals) had a stagno-rheophilous character and was under a strong anthropogenic impact which, among others, resulted in a disturbance of population dynamics.