南黄海表层沉积物中钙质超微化石的分布

DISTRIBUTION OF CALCAREOUS NANNOFOSSILS IN THE SURFACE SEDIMENTS OF THE SOUTHERN YELLOW SEA

对南黄海地区47个表层沉积物样品进行了钙质超微化石分析。结果表明,该区超微化石组合主要以Emiliania huxleyi和Gephyrocapsa oceanica占优势。钙质超微化石总丰度分布不一,主要受水深和黄海暖流的控制。E.huxleyi和G.oceanica两个优势种的平面分布规律也各不相同,E.huxleyi百分含量分布总体上来说与超微化石总丰度分布特征一致:在近岸浅水区含量较低,中央地带丰度较高;G.oceanica百分含量则在靠近南黄海西岸含量较高,离岸较远含量反而变低,反映了其独特的生态习性。

Calcareous nannofossil analysis have been carried out for 47 surface sediment samples taken from the southern parts of the Yellow Sea（120.5°~125.5°E,31.8°~37°N）.The results show that the nannofossils are dominated by the typical marginal assemblages of Emiliania hexleyi and Gephyrocapsa oceanica.The total abundance of calcareous nannofossils varies between 0 and 1451,and is controlled by the water depth and the Yellow Sea Warm Current.The distribution of E.huxleyi and G.oceanica shows a different pattern.E.huxleyi has a similar distribution with the total abundance of nannofossils： higher abundance in the central area and lower abundance in the coastal area.G.oceanica,however,is more abundant in the western coastal area,but less in the sediments far from the coast.These results indicate that the distribution of E.huxleyi were controlled mainly by the water depth and the Yellow Sea Warm Current,and the distribution of G.oceanica is probably linked to the seawater nutrient.