The ecological characteristics of zooplankton community in the Bohai Sea
渤海浮游动物群落生态特点 Ⅱ.桡足类数量分布及变动

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