春夏季吕泗渔场水产种质资源保护区浮游动物分布特征

Distribution characteristics of zooplankton in National Aquatic Germplasm Conservation Area in Lüsi fishing ground of East China in spring and summer

采用2010年5月(春季)和8月(夏季)对吕泗渔场小黄鱼银鲳国家级水产种质资源保护区进行的2个航次调查数据,分析该海域的饵料浮游动物种类组成、数量分布、优势种和多样性。结果表明:该海域的饵料浮游动物丰度春季(163.1 ind·m^(-3))高于夏季(46.3 ind·m^(-3)),生物量夏季(699 mg·m^(-3))高于春季(324 mg·m^(-3)),西南部水域的丰度和生物量均高于东北部水域;两个季节共同的优势种是中华哲水蚤(Calanus sinicus)、真刺唇角水蚤(Labidocera euchaeta)、拿卡箭虫(Sagitta nagae)和中华假磷虾(Pseudeuphausia sinica),其中中华哲水蚤占绝对的优势,其次是真刺唇角水蚤;饵料浮游动物多样性指数夏季(2.27)低于春季(2.51),整体群落结构较稳定,为该保护区的鱼类尤其是幼鱼提供了丰富的饵料基础。

Two navigation surveys in May （spring） and August （summer） of 2010 were conducted to investigate the species composition, abundance distribution, dominant species, and species diversity of diet zooplankton in the national protection area of aquatic germplasm in Lüsi fishing ground. In the study area, the abundance of diet zooplankton was higher in spring （163.1 ind·m-3） than in summer （46.3 ind·m-3）, while the biomass was higher in summer （699 mg·m-3） than in spring （324 mg·m-3）. Both the abundance and the biomass of the zooplankton were higher in the southwest than in the northeast. The dominant species in both spring and summer were Calanus sinicus, Labidocera euchaeta, Sagitta nagae, and Pseudeuphausia sinica. C. sinicus was in absolute superiority, followed by L. euchaeta. The index of species diversity was lower in summer （2.27） than in spring （2.51）. Overall, the zooplankton community had a stable structure, which provided basis for supplying rich feedstuffs to the fishes, especially juvenile fishes, in this conservation area.