珠江口游泳生物组成的多元统计分析

1997年12月到1998年11月，利用尖尾罟网和掺缯网船在珠江口水域进行了周年月度渔业资源调查，共捕获268种游泳生物，其中鱼类167种，足类7种，虾蛄类10种，虾类31种，蟹类53种。采用主成份分析、回顾分析和聚类分析等统计方法分析游泳生物的组成、生物学及季节变化等特征。结果表明，珠江口水域的游泳生物主要是沿岸性或河口性的小型种类，基本由当年生个体组成，它们与高温低盐水环境特征相适应，构成珠江口游泳生物组成的主体。游泳生物组成的季节变化明显，但对于鱼类的底栖类群和中上层类群则存在着时间上的差异。

Multivariate analysis of nekton composition in Pearl River estuary waters

The monthly survey of fishery resources was conducted with beam trawl and hang trawl in the Pearl River estuary waters from December 1997 to November 1998, and 268 species of nekton were captured, including 167 species of fishes, 7 species of cephalopoda, 10 species of mantis shrimps, 31 species of shrimps and 53 species of crabs. The species composition, biological characteristics and seasonal variation of nekton were analyzed by principal component analysis, regression analysis and hierarchical cluster analysis. The results indicate that nekton in the waters are mainly coastal or estuarine small body species adaptable to the water environment of high temperature and low salinity, mostly consisting of individuals of the same year, which were the principal parts of the nekton group. Seasonal variation of the composition of the nekton group was obvious, but for the demersal fishes and the pelagic fishes, their species composition varied with time.