东海甲藻赤潮前后典型断面营养盐变化及其补充初探

Preliminary study on variation and supply of nutrients in typical sections of the East China Sea before and after Dinoflagellate blooms

关键词:  东海  甲藻赤潮  营养盐  典型断面

Key words:  East China Sea  The Dinoflagellate blooms  Nutrients  Typical section

摘要:

根据2005年春、夏季东海赤潮高发区两个航次的综合调查资料，对调查海域大规模甲藻赤潮过程中典型断面的营养盐变化特征进行了分析,并在此基础上初步探究了营养盐补充的主要来源。结果表明，营养盐持续补充在该海区甲藻赤潮过程中起到了重要作用，调查海区表层主要受长江冲淡水等陆源淡水补给作用的影响，而底层主要受台湾暖流补给作用的影响，且陆源补给作用对调查海区北部的影响强于南部，台湾暖流对调查海区南部的影响强于北部；长江冲淡水等陆源影响对硅酸盐、氮盐补给程度较高，其次是磷酸盐；台湾暖流对调查海区底层磷酸盐补给程度最高，对氮盐和硅酸盐的补给作用不明显；此外，底层沉积物释放作用可能也是硅酸盐补给的重要来源之一。

Abstract:

Two comprehensive surveys were conducted in the frequent Harmful Algal Bloom (HAB) areas of the East China Sea in spring and summer of 2005. Based on the analysis of the variation of nutrients in typical sections, the supply of nutrients was discussed. The results show that the constant nutrient supply is very important for the occurence of HABs in the surveyed areas. The surface water of these areas were mainly influenced by terrestrial source of nutrients，such as Changjiang diluted water (CDW); while the bottom water were mainly influenced by Taiwan warm current (TWC). Moreover, the influence of terrestrial source is stronger on the northern part than on the southern part, and the influence of the TWC is stronger on the southern part than on the northern part. The quantities of SiO3-Si and DIN supply were higher than PO4P in CDW，while TWC supplied more PO4P then the other nutrients. Moreover, the release of sediment is one of the important source of supply for SiO3-Si. 