长江口邻近海域丰水季大型底栖动物群落特征

为了研究长江口丰水季邻近海域大型底栖动物群落特征, 我们根据2012年6、8和10月长江口邻近海域大型底栖动物的调查资料, 应用双因素方差分析(Two-Way ANOVA)、聚类分析(Cluster)、非参数多维标度排序(Non-metric Multidimensional Scaling, NMDS)以及丰度生物量比较曲线(Abundance-Biomass Comparison Curves, ABC Curves)对数据资料进行分析。本研究共记录大型底栖动物181种, 其中多毛类动物82种, 甲壳动物46种, 软体动物31种, 棘皮动物11种, 其他类群11种。大型底栖动物丰度、生物量、种类丰富度和多样性指数月份间差异和空间差异均不显著。均匀度指数月份间差异不显著, 而空间上远海显著高于近海。6、8和10月大型底栖动物在20%的相似性水平上划分为3-4个群聚, 不同站位相似性水平较低。ABC曲线表明远海大型底栖动物群落受扰动的程度小于近海。受人类活动的持续影响, 长江口邻近海域大型底栖动物种类变化剧烈, 空间分布不均匀。

Characteristics of a macrozoobenthic community in the sea adjacent to the Yangtze River estuary during the wet season

To explore the characteristics of a macrozoobenthic community in the sea adjacent to the Yangtze River estuary during the wet season, macrozoobenthic samples were collected during June, August, and October, 2012, and data were analyzed using statistical methods including Two-Way ANOVA, Cluster analysis, Non-metric Multidimensional Scaling (NMDS), and Abundance-Biomass Comparison Curves (ABC Curves). A total of 181 macrozoobenthic species were recorded, with 82 species of Polychaeta, 46 Crustacea, 31 Mollusca, 11 Echinodermata and 11 species belonging to other groups. The abundance, biomass, Margalef’s richness index (d), Shannon-Wiener index (H'), and Pielou index (J') did not show any significant temporal or spatial differences except that J' in the offshore area was significantly higher than that found in the inshore area. Three to four macrozoobenthic assemblages were identified using the 20% similarity level and a low similarity level among stations was also observed. ABC curves revealed that the macrozoobenthic community in the offshore area was less disturbed than that in the inshore area. As a result of the continuous impact of anthropogenic activities, the macrozoobenthic community was severely disturbed and unevenly distributed in the sea adjacent to the Yangtze River estuary.