长江中游监利江段鱼类群落结构研究

基于2013~2015年、2017~2018年长江中游监利江段的鱼类资源监测数据，采用多样性指数和多元统计方法分析该江段的鱼类群落结构特征。研究表明:5年共监测到鱼类68种，隶属于6目13科，其中鲤形目共46种；2018年监测的鱼类种类数要多于其他年份。各年份的均匀度指数值相差不大，2018年Shannon Wiener指数值和Margalef丰富度指数值要大于前面4个年份，优势度指数值有一定波动，但值均偏低。ABC曲线及W统计表明2013年和2014年鱼类群落结构受到了人类活动的严重扰动，而2015、2017和2018年受到人类活动的扰动程度不大。聚类分析和非度量多维尺度分析显示鱼类群落可以分为三组，但相似性分析表示三组间无明显差异。

Studies on Fish Community Structure in Jianli Section of the Middle Reaches of the Yangtze River

Based on the fish resources surveys in Jianli section of the Yangtze River from 2013 to 2015 and 2017 to 2018, the fish community structure and species diversity were described using Shannon Wiener diversity index, Simpson dominance index, Margalef’s richness index, Pielou’s evenness index and multivariate statistical analysis, respectively. A total of 68 fish species belonging to 13 families and 6 orders were collected during monitoring periods. They were dominated by Cypriniforme. The numbers of fish species in 2018 were more than those in other years. There were no significant variations in Pielou’s evenness index in different years, while Shannon Wiener diversity index and Margalef’s richness index in 2018 were highest in all years. Simpson dominance index fluctuated to some extent, but they were all low in the five years. The abundance biomass curves (ABC) and W statistical analysis indicated that fish community was suffering with high disturbance in 2013 and 2014, while the community was not disturbed in 2015, 2017 and 2018. The fish community structures in the five years were divided into three groups by using cluster analysis and nonmetric multidimensional scaling (NMDS) methods．No significant difference was found by the analysis of similarity statistics (ANOSIM) during these three groups.