TY JOUR TI ANALYSIS OF PRODUCTIVITY OF SPONGE (SPONGILLIDAE) GROWING IN WATER BODIES OF THE VOLGA RIVER DURING REGRESSION OF THE CASPIAN SEA KW the Caspian Sea KW sea level KW freshwater body KW sponge colonies KW ground KW watercourse KW freshwater sponge KW the Volga delta KW commercial volume JO Vestnik of Astrakhan State Technical University. Series: Fishing industry AU Franov, N.. AU Nevalennyy, A.. AU Sokolsky, A.. PY 2019 IS 2019 PB Astrakhan State Technical University