The species composition , biological characteristics and seasonal variation of nekton were analyzed by principal component analysis , regression analysis and hierarchical cluster analysis .

采用主成份分析、回归分析和聚类分析等统计学方法分析游泳生物的组成、生物学及季节变化等特征。

Estuaries are the home of many living species that can be classified into plankton , nekton and benthos based on their swim ability and the habitats they live .

河口生物种类繁多，根据它们的运动能力和栖息环境的不同可分为浮游生物、游泳生物和底栖生物。