长江口北支大型底栖动物群落周年变化特征

Anniversary variation characteristics of benthic animal community in the north branch of the Yangtze River estuary

分析了长江口北支滩涂大型底栖动物的群落结构和多样性变化特征。共采集大型底栖动物78种,包括环节动物7种、软体动物23种、节肢动物28种、脊索动物18种、其它两种,全年优势种有8种。密度为0.08 ind/m2(1月)-1.24 ind/m2(7月),生物量为0.006 g/m2(2月)-0.58 g/m2(5月),Margalef丰富度指数(D)为0.82(1月)-3.88(7月),Pielou均匀度指数(J)为0.60(9月)-0.86(1月),Shannon-Wiener多样性指数(H')为1.59(2月)-2.76(10月)。底栖动物密度与环境因子进行相关性分析显示,北支潮间带的大型底栖动物群落按照盐度、沉积特征等不同可分为3组,盐度和温度是影响底栖动物群落分布的主导因子。

The community structure and diversity characteristics of large benthic animal in the north branch of the Yangtze River estuary were analyzed. The collected 78 species included 23 species of mollusks,7 species of annelids,28 species of arthropods,18 species of chordates,and 2 others. Also eight dominant species were found throughout the year. The density was from 0. 08 ind /m^2（ Jan.） to 1.24 ind /m^2（ July）. The biomass was from 0.006 g/m^2（ Feb.） to 0.58 g/m^2（ May）. The Margalef index（ D） was from 0.82（ Jan.） to 3.88（ July）. The Pielou index（ J） was from 0.60（ Sep.） to 0.86（ Jan.）. The Shannon-Wiener index（ H＇） was from 1.59（ Feb.） to 2.76（ Oct.）. Based on the analysis between density and environmental factors,there were three groups according to the salinity,sedimentary characteristics and other aspects. Moreover,salinity and temperature played a main role on the benthic species distribution.