Vertical distribution and cellular heat resistance of bottom animals from the Possyet Bay (Japan Sea)
- A. V. Zhirmunsky1
© Biologischen Anstalt Helgoland 1973
1. Investigations on 15 mass species of bottom animals (Bivalvia, Gastropoda, Asteroidea, Ascidia), performed by means of aqualungs in semi-enclosed bays of the Possyet Bay (Peter the Great Bay of the Japan Sea), have revealed a clear zonality in their vertical distribution. This finding is in contrast to the situation found near islands and capes of Peter the Great Bay, where species distributions are weakly connected with depth, but to a considerable degree determined by the nature of substrate, degree of tides and presence of predators.
2. These differences may be explained by differences in summer temperature conditions, considerable decrease of the temperature gradient with increase of depth in semi-enclosed bays, insignificant surface temperature differences and, in depths of about 20–30 m, by intensive water mixing near islands and capes.
3. Comparison of the vertical distribution of species from the Possyet Bay with their cellular heat resistance (species-specific feature, used for characterizing genetic heat adaptation) reveals conformity between these indices.
4. These results and literature data suggest that the differences in vertical distribution of the bottom invertebrates living in coastal waters are the result of the species-specific adaptation of their cells to environmental temperature; differences in protein structure of different animals are considered to provide the basis of this phenomenon.