洪泽湖双壳类调查

Survey of Freshwater Bivalves in Hongze Lake in Western Jiangsu Province

2017年9月和2018年3月,采用网格法布点,用齿间距0.6 mm、耙宽70 cm的划耙在底质中前行20 m的方法调查了洪泽湖双壳类的种类、生物量、密度和多样性指数。共采集到双壳类14种,隶属于3科11属,有我国淡水双壳类特有种7种,分别为湖沼股蛤Limnoperna lacustris、射线裂嵴蚌Schistodesmus lampreyanus、球形无齿蚌Anodonta globosula、扭蚌Arconaia lanceolata、三角帆蚌Hyriopsis cumingii、圆头楔蚌Cuneopsis heudei和矛形楔蚌C.celtiformis,优势种为河蚬Corbicula fluminea。洪泽湖双壳类的生物量和密度分别为29.57 g·m^(-2)和9.8 ind·m^(-2),河蚬在总生物量和密度中占比最大,分别达62.24%和71.59%。Shannon多样性指数(H)、均匀度指数(J)和丰富度指数(D)分别为1.89、0.50和0.95。分析表明,洪泽湖双壳类趋于小型化,处于严重干扰状态,而人为干扰因素如过度捕捞、采砂等可能是其主要原因,建议合理增殖,增设保护区,控制捕捞强度,以保护和恢复其物种多样性。

Surveyed the species,biomass,density and diversity index of bivalves in Hongze Lake in western Jiangsu province in September 2017 and March 2018,using grid method to arrange points,and moving row rakes with tooth spacing of 0.6 cm and rake width of 70 cm forward 20 m in the bottom.A total of 14 species belonging to 11 genera,3 families were found,including 7 endemic species of Chinese freshwater bivalves,namely Limnoperna lacustris,Schistodesmus lampreyanus,Anodonta globosula,Arconaia lanceolata,Hyriopsis cumingii,Cuneopsis heudei,C.celtiformis,and Corbicula fluminea,and the dominant species of Corbicula fluminea.It was shown that the freshwater bivalves had average biomass of 29.57 g·m^(-2)and density of 9.8 ind.·m^(-2),with the maximal Corbicula fluminea contributor to the biomass(62.24%)and density(71.59%),Shannon index(H)of 1.89,Pielou index(J)of 0.50,and Margalef index(D)of 0.95.The findings indicated that the bivalve’s resource had a miniaturized tendency and was seriously disturbed in Hongze Lake,by human activities including overfishing and sand mining.It suggested that different species of bivalves released for enhancement reasonably,the protection zone be established,and the fishing intensity must be controlled to protect and recover of the species diversity of bivalves in Hongze Lake.