The current state of macrozoobenthos of some small reservoirs the North Kazakhstan region

Abstract

Awareness of ecosystem integrity increases the relevance of collecting information on the biodiversity of water bodies of various types. The episodic nature of studies of small water bodies, along with the high variability of their hydrological, hydrochemical, and morphometric parameters, is the reason for the lack of a full assessment of the state of biota. The current paper provides information on macrozoobenthos of four small water bodies in the North Kazakhstan region. The study revealed 59 representatives with a predominance of insects in the benthofauna. Bottom complexes of shallow temporary water bodies were characterized by a wider spectrum with a greater proportion of insects relative to similar variables for lake Big Koskol. The basis was composed by species adapted to fluctuations of water availability, which led to a relatively stable state of biocenoses against the background of a significant range of quantitative characteristics of zoobenthos. More abundant development of benthic invertebrates highlighted in the lake Bolshoy Koskol (with the dominance of amphipods) and in the temporary water body T26 (with the predominance of insects). By the size of the average annual zoobenthos biomass — 29–31.5 g / m2 — the mentioned above water bodies were classified as highly productive. The level of development of benthic organisms in water bodies T20–T14, where Vermes were the leaders in biomass assessed as increased productive and moderate productive (10.3–3.1 g/m2 respectively). A low faunistic similarity of macrozoobenthos was noted, indicating the originality of the benthic complexes of the studied water body, which once again emphasizes the role of small water body in maintaining the biodiversity of the ecosystem. Relatively high structural variables of benthocenoses indicate a stable ecological state of bottom communities. The abundance of zoobenthos creates the prerequisites for the utilization of the studied and similar water bodies for organizing amateur — sport fishery and the extraction of feed used in aquarium fish farming