Metabolism Variations in the Bivalve Mollusk Anadara kagoshimensis Tokunaga, 1906 (Bivalvia: Arcidae) under Upwelling Conditions in the Black Sea (Experimental Data)

Studies of the energy metabolism in a bivalve mollusk, the ark clam Anadara kagoshimensis (Tokunaga, 1906), were carried out for the first time under experimental conditions simulating dynamic variations in the seawater characteristics at the stages of development and end of upwelling event in the Black Sea. It was shown that the level of energy metabolism of A. kagoshimensis, while being in the zone of upwelling formation, decreased, on average, by 5% per degree of temperature decrease. During the upwelling relaxation phase (14 → 26°C), the restoration of the respiration intensity parameters of the clam was slower than expected, with a temperature coefficient of Q₁₀ = 1.31. The acidification of the seawater by 1.0 (up to рН 7.2), combined with a temperature decrease (26 → 20°C), aggravated the negative effect by 25–45%. It has been found that the clam A. kagoshimensis reduces energy expenditure by approximately 60% under upwelling conditions (cold stress and acidification). The consequences of the negative effect of a sharp temperature variation lead to a delay in the metabolism recovery to normal values.