秋季南黄海西部营养盐的分布及其与环流场的关系

Tht distribution of nutrients and the relationship of them with the circulation condition in the western southern Huanghai Sea in autumn

重点分析和研究了秋季南黄海西部营养盐的分布状况和水文特征,并在此基础上探讨了营养盐分布及其运移规律与该海域环流场的关系。结果表明:长江冲淡水、苏北沿岸水以及鲁北沿岸水所引起的物质输入是导致南黄海西部近岸海域三个营养盐含量高值区形成的主要因素;由于跃层阻隔以及底层有机物的氧化分解,调查海域中部底层水体也存在较大面积的营养盐含量高值区,其范围与底层的外海高盐冷水域及DO和pH低值区面积相仿;底层营养盐的分布特征印证了南黄海西部沿岸流是一支沿冷水团锋面南下的锋区强流,该流动对营养盐向东南的输运趋势发挥着重要的作用,而且这一输运态势也进一步指示了黄海水与东海水的混合与交换过程。通过对营养盐三种典型的断面分布类型的分析,在一定程度上阐明了长江冲淡水、黄海西部沿岸流、黄海冷水团残留水和黄海暖流对营养盐垂向分布及其输运的影响过程,并揭示了南黄海西部海域由南向北逐渐减弱的垂向混合规律。

Based on the data collected from the southern Huanghai Sea investigation during October and November,2007,an analysis of the distribution of nutrients and hydrological characteristics were focused on,moreover,the relationship between the transportation pattern of nutrients and circulation condition was also studied.The result shows that the material input caused by the Changjiang diluted water,the North Jiangsu（Subei） coastal water and North Shangdong（Lubei） coastal water leads to forming three areas with high nutrients concentration in the western coast of the southern Huanghai Sea;Because of the barrier effect of thermocline and the decomposition of organic matter,a large area with high nutrients concentration also exists in the bottom water of the central survey region,its scope is similar with the high silinity-cold water mass,the low-oxygen area as well as the low-pH area at the offshore bottom;the distribution of nutrients in the bottom water confirms that the Western Coastal Current of the southern Huanghai Sea in autumn is a strong flowing to south along the frontal area of the cold water mass,which can play an important role in the transportation of the nutrients to the southeastern sea area,in addition,this transportation trend further indicates the mixture and exchange process of the Huanghai Sea water with the East China Sea water.Simultaneously,through the analysis of three typical types on section distribution of nutrients,the influence of the Changjiang diluted water,the Western Coastal Current of the southern Huanghai Sea,the residual water of the cold water mass and the Huanghai Warm Current on the vertical distribution and transportation process of nutrients was clarified to a certain extent,as well,the rule that the vertical mixture reduced gradually from the south to the north was also revealed.