The species diversity, density and similarity of Gastrotrich fauna of bottom sediments to epiphytic fauna in three farm ponds were investigated. In the studied habitats 31 species of Gas-trotricha belonging to the family of Chaetonotidae were found altogether. In bottom sediments of the ponds there were 29 and on plants 17 species of Gastrotricha. Three species (Heterolepido-derma gracile Rmane, 1927, Chaetonotus disjunctus Greuter, 1917 and Ch. oculifer Kisielewski, 1981) were found to be dominants in bottom sediments with the dominance over 10.0%. H. gracile and Ch. oculifer also occur on vegetation, but their dominance is significantly lower. In turn three species (H. macrops Kisielewski, 1981, H. ocellatum (Mečnikow, 1865) and Lepidodermella squamata (Dujardin, 1841) proved to be dominant on water vegetation, with the dominance over 10.0% in all studied ponds. The value of species diversity index H’ including the number of spe-cies and uniformity of their dominance is from 2.76 to 2.93 for bottom sediments and from 2.60 to 2.72 for plants. The total density of gastrotrich fauna in bottom sediments fluctuated from 350.0 to 920.0 103 indiv. m-2 and on elodeids from 520 to 1110 103 indiv. m-2. The density of gastrotrich fauna of elodeids was higher than in bottom sediments in all the studied ponds. In each of the ponds examined, the differences are statistically significant. The similarity between bottom sediment fauna and epiphytic fauna in each of the studied ponds, cal-culated according to the homogeneity index, was very low and ranged from 44% to 48%.
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