黄、东海陆架2011年秋季活体浮游有孔虫生态分布

Distribution of living planktonic foraminifera on the shelf of the Yellow Sea and the East China Sea in autumn,2011

现代活体浮游有孔虫的生态研究是其古环境重建应用的重要基础。根据黄、东海陆架2011年秋季采集的20个垂直浮游拖网样品,分析了该海域浮游有孔虫的秋季生态分布特征。结果表明,黄海秋季基本上没有浮游有孔虫的出现。东海共发现13种活体浮游有孔虫,主要优势属种依次为Globigerinoides sacculifer、Pulleniatina obliquiloculata、Globigerina bulloides、Neogloboquadrina dutertrei和Globigerinoides ruber。浮游有孔虫丰度整体上呈现东南高,西北低的分布格局,这种分布格局反映了浮游有孔虫在黄、东海陆架区的分布主要受外海水影响强弱控制。浮游有孔虫主要属种在东海陆架呈现明显的区域分布差异:暖水种G.sacculifer是秋季陆架海区的主要优势种,其分布格局与总丰度基本一致,相对含量从南至北、从东至西逐渐降低,主要受区域表层海水温度变化的控制。G.bulloides与G.sacculifer呈相反的含量分布变化,其高含量主要出现在东海中陆架,从北往南逐渐降低,此外,在闽浙沿岸也有较高含量,表明了温度和生产力是影响G.bulloides在黄、东海陆架分布的主要因素。秋季P.obliquiloculata和N.dutertrei的高含量主要出现在东海南部中陆架区和济州岛西南黄海暖流影响区,可能受暖水与生产力的共同制约。

The knowledge of ecology of modern living planktonic foraminifera is very important for their application in paleoenvironmental reconstruction. The distribution of living planktonic foraminifers has been analyzed on 20 plankton tow samples collected from the shelf of the Yellow Sea and the East China Sea in Autumn,2011. The re- sults indicate that planktonic foraminifera is almost absent in autumn in the Yellow Sea. Thirteen planktonic fo- raminiferal species occurred in the East China Sea, dominated by Globigerinoides sacculifer, Pulleniatina obliquiloculata, Globigerina bulloides, Neogloboquadrina dutertrei and Globigerinoides tuber. The abundance of planktonic foraminifera shows a general pattern,with high abundance in the southeast and low values in the north- west of the study area, which may indicate that the distribution of foraminifers in the study area is mainly controlled by the influence of the open ocean water. The major species of planktonic foraminifera shows apparent different distribution in the East China shelf seas. G. sacculifer, the preponderant species of the shelf seas in autumn, shows a similar distribution pattern with the total abundance. Its relative percentage gradually decreased from south to north, and from east to west, suggesting the control of the variation by regional surface sea temperature. In contrast to the distribution of G. sacculifer,high percentage of G. bulloides mainly occurred in the middle shelf of the East China Sea, and its relative abundance gradually decreased from north to south, and high percentage also occurred in the inner shelf off Min-Zhe coast, suggesting that both temperature and productivity are principal factors controlling the distribution of G. bulloides in the study area. High abundance of P. obliquiloculata and N. dutertrei mainly appeared in the middle shelf of the southern East China Sea and southwest off Cheju Island, possibly modulated by the joint influence of warm water and productivity.