夏秋季浙江岱衢洋虾蟹类群落多样性分析

根据2010年夏季（8月）与秋季（11月）对浙江岱衢洋进行的共2个航次的底拖网渔业资源调查资料,对该海域虾蟹类的多样性进行了分析。结果表明：共捕获虾蟹类15种,它们隶属于1目9科12属;秋季虾蟹类的生物量、尾数密度均明显高于夏季;所有优势种均为广温广盐种,且夏秋两季优势种的生物量与尾数密度占各自总量的比例均超过83%;Mar-galef丰富度指数（D）、Shannon-Wiener多样性指数（H′）和Pielou均匀度指数（J′）夏季均高于秋季,这表明夏季虾蟹类群落的丰富度、多样性与均匀性都较秋季高。另外,夏秋两季的多样性指数（H′）较低,表明人类的活动已对岱衢产生了明显的不利影响。

Analysis on Crabs and Shrimps Community Diversity in Daiquyang of Zhejiang Province During Summer and Autumn

The species diversity of crabs and shrimps in Daiquyang were analyzed based on the data collected from the investigations from summer（August） to autumn（November） in 2009 by bottom trawl. Sweep-area method and analysis of variance were used here. The results showed that： A total of 15 species of crabs and shrimps were caught by bottom trawl, which belonged to 12 genera, of 9 families, 1 orde. Both the biomass and the number abundance density for autumn were significantly higher than those for summer. All the dominant species were eurythermal and euryhaline species. For summer and autumn, the percentage of the dominant species biomass compared with that of all the species was more than 83%, and was same to the number abundance density. Summer and autumn warm temperature species all occupied the dominant position. The Margalef richness index（D）, Shannon-Wiener diversity index（H＇） and Pielou evenness iddex（J＇） for summer were wholly higher than those for autumn, which indicated that the richness, diversity and evenness of the crabs and shrimps community for summer were better. In addition, both the Shannon-Wiener diversity index（H＇） for sum- mer and that for autumn were poorer, it showed that the entironment had been badly influenced by human activities.