A restudy of ostracode assemblages in the surface sediments of the Huanghai Sea

Distribution pattern of ostracodes in the western part of the Huanghai Sea was re-analyzed using the occurrence data of 142 species from 175 surface sediment samples.The high values of ostracode specimen density are generally restricted to depths shallower than 40 m.The species diversity H(S) is higher in the southern part and lower in the northern part of the area studied,the trend which is correspondent to the change of water temperature in the Huanghai Sea.In the area where radial tidal sands is distributed,H(S) reaches its maximum average value.
Six ostracode biofacies were delineated using Q-mode factor analysis,based on the data of 77 samples and 69 species.Their distributions are correspondent with environmental parameters such as water temperature,salinity and substrate type.
Through tracing the geographical distribution of ostracode species in the Huanghai Sea and the East China Sea,it is reconfirmed that the discontinuity of species distribution between the two areas,located at around 32°N,coincides with the boundary of subtropical/warm temperate zones of China seas.