渤海浮游动物群落生态特点 Ⅱ.桡足类数量分布及变动

用1959年全国海洋普查浮游动物中网样品分析渤海浮游动物。尤其是中小型浮游动物的数量分布及变动特点。结果表明，渤海浮游动物全年平均丰度为3841ind／m^3，最大33756ind/m^3，最小6．5ind／m^3。其中桡足类年平均密度为3413ind／m^3，是数量的主要构成者。渤海浮游动物主要的高峰期出现在夏季，此外春、秋两季各自有一个小的高峰。春季峰主要是由双毛纺锤水蚤(Acartia bifilosa)的大量繁殖造成，秋季峰主要是由拟长腹剑水蚤(Oithona similis)构成。夏季峰是由于小拟哲水蚤(Paraclanus parvus)、强额拟哲水蚤(Paracalanus crassirostris)、拟长腹剑水蚤等多种桡足类和一些幼虫大量繁殖造成。渤海浮游动物季节演替比较明显。双毛纺锤水蚤、墨氏胸刺水蚤(Centropages mcmmurrichi)和中华哲水蚤(Calanus sinicus)是春季的优势种；小拟哲水蚤、拟长腹剑水蚤、近缘大眼剑水蚤(Corycaeus affinis)和太平洋纺锤水蚤（Acartia pacifica)是夏季的优势种；拟长腹剑水蚤、真刺唇角水蚤（Lubidocera euchaeta)等是秋季的优势种。数量的水平分布同温度的水平分布趋势基本一致。同盐度趋势相反。

The ecological characteristics of zooplankton community in the Bohai Sea

Samples from twelve consecutive cruises in 1959 were analyzed to determine the distribution patterns of abundance and seasonal dynamics of zooplankton The abundance of zooplankton ranged from 6 5 ind/m 3 in winter to 33756 ind/m 3 in summer with an average of 3841ind/m 3 There were two smaller peaks in April and November respectively Copepoda were major components of zooplankton in the Bohai Sea with an annual average abundance of 3341 ind/m 3 The species which dominated zooplankton changed seasonally: Acartia bifilosa, Centropages mcmurrichi, Calanus sinicus were in spring, Paracalanus parvus, P crassirosrtis, Corycaeus affinis and Acartia pacifica were in summer, and Oithona similis , Labidocera euchaeta were in autumn The seasonal abundance distribution was consistent with the horizontal gradient of temperature and inverse with that of salinity