2010-2011年长江河口及邻近水域春夏季仔稚鱼群落结构及其多样性的研究

根据2010—2011年春夏季对长江河口及邻近水域进行了仔稚鱼生态调查,应用单元和多元统计方法分析了春夏季长江河口及邻近水域仔稚鱼群落结构。4个航次调查共获得27个种类的仔稚鱼,隶属5目14科。优势种类主要包括鳀Engraulis japonicus、凤鲚Coilia mystus、康氏小公鱼Stolephorus commersonii、鮻Liza haematocheila、黄姑鱼Nibea albiflora、黄鳍刺虎鱼Acanthogobius flavimanus和寡鳞飘鱼Pseudolaubuca engraulis等。Shannon-Weaver指数(H′)在调查周期内的波动幅度较大,且2011年明显低于2010年。仔稚鱼群落结构和多样性指数春季年间较夏季年间差异性显著。调查区夏季群落结构年间相似性不高,春季群落结构格局年际变化则较明显。聚类分析表明,春夏季长江河口近岸水域仔稚鱼群落可划分为2个站位组,分别对应于长江河口淡水水域和长江口咸水水域。淡水水域组群落和咸水水域组群落总丰度与盐度相关性较高。表明盐度可能是造成长江河口仔稚鱼群落结构时空差异性的主要原因。

Structure of community and biodiversity of larvae fish in spring and autumn 2010-2011 in Yangtze River Estuary and its adjacent waters

Univariate and multivariate statistics were used to analyze the structure of larvae fish community based on the data collected from the surveys in Yangtze River Estuary and its adjacent waters in spring and autumn 2010-2011.A total of 27 species belonging to 5 orders,14 families were captured from four surveys. The dominant species mainly contained Engraulis japonicus,Coilia mystus,Stolephorus commersonii,Liza haematocheila,Nibea albiflora,Acanthogobius flavimanus and Pseudolaubuca engraulis. The Shannon-Weaver (H') value fluctuated greatly in an investigation cycle,which was appreciably lower in 2011 than that in 2010. The year variations of community structure and diversity index of larvae fish were more significant in spring than those in summer. The larvae fish community was clustered into two groups which coresponded with the freshwater area and brackish water area of Yangtze River Estuary,respectively. The abundance of larvae fish in both groups was mainly affected by salinity,indicating that salinity was the major cause of the spatiotemporal difference of larvae fish community in the Yangtze River Estuary.