Expeditionary Studies of the Current State of the Volga River Avandelta Ecosystem during the Flow Period

As a result of the work of the expedition of the Institute of Oceanology in May 2021, the absolute values of the main hydrophysical, hydrochemical, geochemical, and biological characteristics of the water area of the western part of the Volga River Delta and the adjacent shelf are obtained. The lowering of the Caspian Sea level is leading to an increase in the slow runoff, which appears to be leading to a decrease in the amount of nutrients entering the shelf and a restructuring of the functioning of the ecosystem of the seaward edge of the delta front.