东山湾渔业生物群落结构及生物量分布特征

Characteristics of community structure and biomass distribution of fishery resources in Dongshan Bay

根据2016年4月(春季)和10月(秋季)东山湾拖网定点调查资料,研究分析了东山湾渔业生物群落结构及其生物量分布特征。结果表明,调查共获取渔业生物128种,其中鱼类88种、虾类9种、蟹类19种、口足类4种、头足类8种,主要以暖水性种类为主;春季渔获物优势种为斑鱼祭(Clupanodon Punctatus)、黄吻棱鳀(Thrissa vitirostris)和短吻鲾(Leiognathus brevirostris)等3种,秋季则为日本蟳(Charybdis japonica)、青鳞小沙丁鱼(Sardinella zunasi)、食蟹豆齿鳗(Pisodonophis cancrivorus)、矛形梭子蟹(Portunus hastatoides)、黄吻棱鳀和赤鼻棱鳀(Thrissa kammalensis)等6种,优势种季节更替明显;春、秋季渔业生物群落质量平均资源密度指数分别为214. 91 kg·km-2和265. 19 kg·km-2,数量平均密度指数分别为12. 51×103尾·km-2和12. 02×103尾·km-2,渔业资源有衰减趋势;Margalef种类丰富度指数平均值为5. 112,Shannon-Wiener种类多样性指数平均值为2. 179,Pielou种类均匀度指数平均为0. 635,春季均明显低于秋季,生物多样性处于较低水平。

Based on the data of the trawl fishing survey from Dongshan Bay in April(spring)and October(autumn)2016,the characteristics of community structure and biomass distribution of fishery resources in Dongshan Bay were analyzed.A total of 128 species were collected,including 88 species of fishes,9 species of shrimps,19 species of crabs,4 species of cephalopods and 8 species of stomatopods,mainly dominated by warm water species.Clupanodon Punctatus,Thrissa vitirostris and Leiognathus brevirostris were the dominant species in spring,Charybdis japonica,Sardinella zunasi,Pisodonophis cancrivorus,Portunus hastatoides,Thryssa vitrirostris and Thrissa kammalensis were the dominant species in autumn,and the result showed that dominant species changed evidently during two seasons.Besides,the catch density indices of weight in spring and autumn were estimated to be 214.91 kg·km-2 and 265.19 kg·km-2 respectively,and the catch density indices of number in two seasons were estimated to be 12.51×10 3 ind·km-2 and 12.02×10 3 ind·km-2 respectively,and the result indicated that fishery resources displayed a decreasing tendency.Furthermore,the Margalef richness index,Shannon-weaner diversity index,and Pielou evenness index were respectively 5.112,2.179 and 0.635,the values in spring were significantly lower than those in autumn,and the biological diversity was at a lower level.