Larvae of Winged insects in the structure of macrozoobenthos below the Dnieper

Abstract

Based on the literature data and according to own research, the comparison of
the macrozoobenthos of lower Dnieper before starting of exploitation of
Kakhovka Hydroelectric Station and in current period was being held. The
research was being held in the next water objects: Dnieper courses, Dnieper
distributaries, Kardashinsky liman and Stebliivsky liman. The attention is paid to
the larvae of Diptera insects in the common benthos. The comparison is made on
the criteria of the density and biomass. There are significant changes noted in the
subcomponent of populations of Diptera insects’ larvae in the structure of
macrozoobenthos of floodplain water bodies and less significant – in Dnieper
courses and distributaries. It is pointed out that this phenomenon is directly related
to the change of the water regime of Dnieper.
In the second part of the work, the changes on the species composition of
Diptera insects’ larvae are analyzed in comparison with previous studies based on
mass species of this group. The general tendencies for the lower Dnieper and the
situation for individual water bodies are being recorded. There have been some
changes in biodiversity of Diptera insects’ larvae at the genus level and significant
changes at the species level which occupy a dominant position inside this group.
Conclusions are made about the causes of the detected changes, which confirm
and supply the results of the first part of the research.
Key words: macrozoobenthos, lower Dnieper, Diptera, larvae, mass species.