长江口邻近水域浮游动物群落特征及变动趋势

Character of zooplankton community and its variation in the water near the Yangtze River estuary

根据2000～2003年长江口邻近海域5月和8月8个航次的调查资料,对长江口浮游动物群落特征的变动趋势进行了研究。结果表明,桡足类、毛颚类和异足类在8月种数明显多于5月。8月暖流势力增强的同时淡水水团势力也增强,不同水团交汇处,浮游动物种类数和多样性指数等值线密集排列,外海暖水带来丰富的种类使该季节的种类数和多样性均明显高于5月。盐度是影响长江口浮游动物群落特征最主要的环境因子。

Based on the data of 8 voyages' investigation in May and August from 2000 to 2003 in the fisheries water near the Yangtze River estuary,this paper dealt with the variation trend of species composition and diversity of zooplankton.The results showed that species number of Heteropoda,Chaetognatha and Copepods in August was higher than that in May.The force of warm current enhanced with the enforcing Yangtze River freshwater in August.At the converge of different water current,isoline of species number and diversity of zooplankton were closely arranged.The rich species brought by warm current in August increased the species number and diversity value in August and were higher than those in May.Salinity was the most important environmental factor affecting community character of zooplankton in the water near the Yangtze River estuary.