中街山列岛水域甲壳类资源及其群落多样性

根据2010年5月(春季)、8月(夏季)、11月(秋季)与2011年2月(冬季)对中街山列岛水域进行的4个航次底拖网渔业资源调查资料,分析了该海域的甲壳动物资源状况和群落多样性。结果表明:该海域四季共捕获甲壳动物33种,隶属于2目,17科,27属,其中虾类20种、蟹类12种、虾蛄类1种;葛氏长臂虾(Palaemon gravieri)四季均为该海域的优势种;甲壳类生物量密度以秋季最高(426.96 kg.km-2),而尾数密度以冬季最高(1.38×107ind.km-2),春季两者都最低(91.13 kg.km-2和2.43×106ind.km-2),秋季和春季的生物量密度差异极显著(P<0.01),冬季和春季的尾数密度差异也极显著(P<0.01);甲壳类密度指数与平均底温相关性较高(P<0.05);各个季节广温广盐种类数均居主导地位;丰富度指数(D)为1.04～1.61,多样性指数(H')为1.27～1.57,均匀度指数(J')为0.61～0.69,群落多样性指数各季节间差异不显著(P>0.05)。

Resource density and community diversity of crustaceans in the waters of Zhongjieshan Islands

Based on the bottom trawl survey data from spring(May),summer(August),autumn(November) in 2010 and winter(February) in 2011 in the waters of Zhongjieshan Islands,the resource density and community diversity of crustaceans were studied.Thirty-three species belonging to 18 genus,of 14 families,2 orders of crustaceans were caught,including 13 species of shrimps,7 species of crabs and 1 specie of squilla.Palaemon gravieri was the dominant species in all seasons.The biomass density reached the maximum in autumn(426.96 kg·km-2) and the number abundance density reached the maximum in winter(1.38×107 ind·km-2),and the minimum in spring(91.13 kg·km-2,2.43×106 ind·km-2).The biomass density in spring was especially different with that in autumn(P<0.01),and the number abundance density in winter was also especially different with that in spring(P<0.01).The abundance density of crustaceans was significantly correlated with the average sea bottom temperature(P<0.05).The eurythermal and euryhaline species all occupied the dominant position in all seasons.The Margalef richness index(D) was 1.14-1.61,Shannon-Wiener diversity index(H′) was 1.27-1.57,and Pielou evenness index(J′) was 0.61-0.69.No significant difference was found in the diversity indices among 4 seasons(P>0.05).