Распространение Dreissena polymorpha (Pallas, 1771) и Dreissena bugensis (Andrusov, 1847) в Чебоксарском водохранилище в начале XXI векастатьяИсследовательская статья
Аннотация:D. bugensis вытеснила D. polymorpha из наиболее подходящих для себя биотопов Чебоксарского водохранилища, где получила массовое развитие.
Dreissena polymorpha was not numerous in r. Volga before a damming of the river. For 3-5 year of existence Cheboksary water basins has widely extended. Appeared in 1990th years Dreissena bugensis in 10 years has received mass development and has superseded a D. polymorpha from the biotopes most suitable for. In deep-water zones (14-16 m) on grey silts in lake and damsides departments of water basins quantitative characteristics of D. bugensis have reached tens hundreds individuals and several kg on 1 m2, and prevails young individuals. Among cenosis D. bugensis the D. polymorpha is not revealed.
Number D. polymorpha in a water basin rather low - 40-160 ind./m2 is found out in top and average river departments of Cheboksary water basins on depths about 7 m, and in a littoral zone on silting sand and sand-stony grounds. D. polymorpha - the unique representative of dreissenas of sites of a mouthes of the rivers of Oka and Sura.
Possibly, mass development of a D. bugensis has occured to end of stabilization of conditions of an environment to Cheboksary a water basin. The increase in depths in connection with filling of a water ba-sin and strong it accumulation of silt, was created with preconditions for successful development of dreis-senas, and, as well as in water basins below across Volga, intensive replacement of a D. polymorpha and by a D. bugensis is observed.
