The natural food base of the ponds in Noginsky district of Moscow region

Abstract

The purpose of this work was to study the natural food base of the ponds in the Noginsk district of the Moscow region in October-November 2022. The selection of hydrobiological materials was carried out in October-November 2022. The pond №1 is a main pond of the EPB of RRIFF, a branch of the FSBSI FRC RIAH named after L.K. Ernst, with an area of 4,48 ha, fertilized with goose and duck droppings. Pond № 2 is ownerless, with peat soil, with an area of about 21,27 hectares. From a fishery point of view, the state of phytoplankton turned out to be more favorable in the ownerless pond. The biomass of phytoplankton in this pond is higher, it is formed mainly by green algae, consumed by both juvenile fish and planktonic organisms, through which the primary production is transferred to the higher levels of trophic pyramid. In the pond № 1, the biomass is much lower and in many respects formed by low-edible blue-green algae. The species diversity of the zooplankton in the EPB RRIFF pond, fertilized with waterfowl droppings, is significantly higher than in the big ownerless pond. The zooplankton biomass here is more than 2 times higher. The number of zooplankton is 1,34 times higher. The percentage of oligochaetes in the benthic invertebrate communities samples from the pond № 1 (68%) indicates moderate water pollution in October-November 2022 with organic matter. Thus, the head pond of the EPB RRIFF, fertilized with waterfowl droppings (the integrated technologies), demonstrated for the benthic invertebrate communities the best indicators of the natural food base state, both in general and in terms of indicators of the individual taxons. The components of the natural food base, which are crucial for the fish nutrition: phytoplankton and benthic invertebrate communities, turned out to be higher in October-November 2022 in the EPB RRIFF pond, fertilized with waterfowl droppings. However, the indicators of phytoplankton were better in the ownerless pond of the Noginsk district of the Moscow region. One of the reasons for the less favorable state of phytoplankton in the EPB RRIFF pond may be the eating of green algae by zooplankton.