长江河口软体动物的调查

本文取材于1980～1996年长江河口的多年调查资料。调查表明:长江河口软体动物种类较贫乏,共采集到软体动物10种。软体动物的年平均生物量为54.25g·m~(-2),占长江河口底栖动物总生物量的88.4％,其中河蚬为软体动物的优势种,其生物量占软体动物的93.8％。长江河口软体动物的分布和种类的贫乏与长江的流速、含砂量、河口盐度变化幅度有密切的关系。此外,在长江河口上海江段首次采集到唯一的一个扭蚌标本。

SURVEYS OF MOLLUSCS IN THE ESTUARINE OF THE CHANGJIANG RIVER

Based on the survey data collected from the estuarine of the Changjiang River from 1980 through 1996, the surveys indicated that the species of molluscs were rather poor in the estuarine of the Changjiang River, and a total of 10 species of molluscs were collected. The annual biomass are 54.25g·m-2 on average, representing 88.4% of the total biomass of bentos in the estuarine of the Changjiang River. Among them, Corbicula flaminea are the predominant, whose biomass account for 93.8% of the, molluscs. The distribution of molluscs and the lack of species in the estuarine of the Changjiang River bear a close relationship to the flow rate, sand content and the changing rate of the estuarine salinity. In addition, the only Arconaia specimen was collected for the first time at the Shanghai segment in the estuarine of the Changjiang River.