ТАКСОЦЕН POLYCHAETA В ПРИБРЕЖНОЙ АКВАТОРИИ ОЗЕРА ДОНУЗЛАВ

Abstract

This work is based on the data collected during the benthic survey of soft sediments in the coastal area of the of Lake Donuzlav conducted in August, 2020. The current status of the species composition of polychaetes in Lake Donuzlav was investigated. The samples were collected using a manually operated grab sampler with a capture area of 0.04 m2 at the depths from 1 to 8 m. The following indicators were used to describe the quantitative development of benthos: abundance, biomass, occurrence, density index, and Czekanowski-Sørensen index. A total of 31 species of polychaetes have been found. The average values of polychaetes abundance and biomass in the investigated area were 239±51 ind./m2 and 1.537± 0.599 g/m2, respectively. The main contribution to the total abundance is made by Spio decorata , and to the total biomass by Lagis neapolitana. The largest number of species and the highest abundance were recorded at the depths of 1.1-2 m. The largest biomass was recorded at the depths of 6.1-7 m. The ranked series according to the density index is headed by L. neapolitana , Glycera tridactyla , and S. decorata . The trophic structure of polychaetes is represented by poly-, phyto-, detritophages, carnivores, and the animals, the food spectrum of which has not been studied. The most widely represented group is carnivores; it comprises 10 species of polychaetes. The least number of species (1) was recorded for phytophages. Over 1990-2020, 73 species of polychaetes were identified; they belonged to 29 families and 56 genera.