岱衢洋鱼类资源及其群落多样性的季节变化

根据2010年春季(5月)、夏季(8月)、秋季(11月)与2011年冬季(2月)对岱衢洋进行的共4个航次的底拖网渔业资源调查资料, 对该海域的鱼类资源状况及其多样性进行了分析, 结果表明: 所捕获的38种鱼分别隶属于1门2纲8目21科31属; 暖温性鱼类无论在种类数量还是生物量与尾数密度方面均居主导地位; 凤鲚四季均为该海域的优势种; 在时间分布上, 生物量与资源尾数密度均以夏季为最高, 而冬季则恰好相反, 且该两季的生物量与资源尾数密度间均存在显著差异(P<0.05), 另外, 在空间分布上, 生物量与尾数密度四季总体上均呈北高南低、东高西低的趋势; 生物量与平均底层温度呈二次曲线相关(P<0.01); 春、秋两季的Margalef丰富度指数( D )、Shannon-Wiener多样性指数( H' )和Pielou均匀度指数( J' )均存在显著差异(P<0.05); 与东海近、外海海域鱼类群落的多样性比较, 岱衢洋的Shannon- Wiener多样性指数( H' )较低。

Seasonal variations of fish resources and its community diversity in Daiquyang

The resources status and species diversity of fish in Daiquyang were analyzed based on the data collected from the investigations from spring(May),summer(August) and autumn(November) in 2009 to winter(February) in 2010 by bottom trawl.There are three methods including sweep area method,biodiversity analysis and analysis of variance(ANOVA).The results showed that: A total of 38 species of fish were caught by bottom trawl,which belonged to 31 genera,of 21 families,8 orders,2 classes and 1 phylum.For percentage of number of species,biomass and number abundance density,warm temperature spe-cies all occupied the dominant position.Coilia mystus was the dominant species in all the seasons.On temporal distribution,both the biomass and the number abundance density in summer were the highest,but opposite in winter,and the biomas in summer was significantly different from that in winter(P<0.05),and same to the number abundance density(P<0.05).On spatial distribution,both the biomass and the number abundance density in northern area were higher than those in southern area,and those in the eastern were higher than those in the southern.By correlation test,the relationship between the biomass and average sea bottom water temperature can be denoted by binary curve(P<0.01).The Margalef richness index(D),Shannon-Wiener diversity index(H′) and Pielou evenness index(J′) in spring were significantly different from those in autumn(P<0.05).Compared with offshore water and deep sea in East China Sea,the Shan-non-Wiener diversity index(H′) in Daiquyang was lower.