Seasonal Dynamics of Planktonic and Bottom Communities of the Chernavka River (Eltonsky Nature Park)
摘要
The results of studies of the seasonal dynamics of macrozoobenthos, meiobenthos, and planktonic communities throughout the polyhaline Chernavka River flowing through the territory of the Eltonsky Nature Park are presented. Zoobenthos communities in all research seasons are characterized by consistently high abundance, biomass, and production, the main contribution to which is made by ostracods Cyprideis torosa, halophilic polycyclic chironomids Cricotopus salinophilus, and biting midges Palpomyia schmidti. The average values of the production of macrozoobenthos during the research period of the Chernavka River (1.295 g C m–2 day–1) were higher than the average daily production of this group of aquatic organisms in the coastal lagoons of the northern part of the Adriatic Sea, and the production of meiobenthos (0.13 mg C m–2 day–1) was an order of magnitude or more higher than that known for freshwater lakes of all trophic types and close to the values characteristic of the tidal zone some seas and estuaries. The large amounts of zoobenthos production are due to the high water temperature from April to October and the high production of the primary trophic link. An increase in production indicators from the middle to the lower reaches of the river has been established, which determines a stable food base for native and migratory waterfowl.