前处理方法对北黄海沉积物粒度的影响

INFLUENCE OF DIFFERENT PRETREATMENT PROCEDURES ON THE PARTICLE-SIZE DISTRIBUTION OF SURFICIAL SEDIMENTS IN THE NORTHERN YELLOW SEA

采用不同方法对北黄海底质样品进行了粒度分析前处理 ,以探讨有机质和碳酸盐对北黄海沉积物粒度的影响。结果表明 ,去除有机质或碳酸盐后 ,粗粒沉积物 (呈双峰分布 )粒度分布的峰态明显变宽 ,平均粒径及粗颗粒 (>3 2 μm)组分含量明显增加 ;而细粒沉积物的粒度分布发生明显细偏 ,表现为众数的细化及平均粒径和粗颗粒含量的降低。北黄海底质沉积物的有机碳含量变化与沉积物的平均粒径呈明显的负相关 ,暗示了浅海沉积物中有机碳的输运和积聚主要是伴随着细颗粒组分发生 ;而碳酸盐含量同沉积物粒度的关系不甚明确 。

Surficial sediments from the northern Yellow Sea are pretreated by different methods for grain size analysis, in order to determine the influences of organic matter or carbonate on the particle size characteristics. The results show that the grain size distributions, pretreated by removing the organic matter or carbonate, are modified to various degrees. 1) The kurtosis of coarse sediments (with bimodal characteristics) becomes smaller, whilst mean grain size and the content of coarse fractions (>32μm) increase. 2) The grain size distribution of fine sediments is associated with a more negatively skewed pattern and a decrease in the mean grain size and the content of coarse fractions. The content of organic carbon is negatively correlated with the mean grain size, indicating that the transport and deposition of organic matter is associated mainly with the fine fractions in the northern Yellow Sea. However, the carbonate contents show an ambiguous correlation with the mean grain size, indicating that the source, rather than the sediment transport determines the carbonate content in the northern Yellow Sea.