黄东海悬浮泥沙浓度的垂向分布特征及其回归模型

Characteristics and regression equations for vertical distribution of suspended sediment concentration in the Yellow Sea and East China Sea

以1959年至2006年期间，东中国海域现场调查的24个航次4813组悬浮物（泥沙）浓度数据资料为基础，采用相关分析和回归分析等方法，研究了东中国海域悬浮物浓度的垂向分布特征，给出了适用于不同季节、不同区域的悬浮物浓度的垂向分布模型。结果表明：悬浮物垂向浓度呈现明显的冬、春季高，夏、秋季低的特征；悬浮物浓度的大小与相对水深相关性良好，而水深对悬浮物浓度的影响则表现在其垂向梯度变化方面：垂向浓度梯度在长江口至杭州湾一带的河口区（A类站）呈现出高值，在与海岸线平行的苏北浅滩至闽浙沿岸的近滨区（B类站）呈现中值，外滨（C类站）的广大海域则呈现明显的低值；春、夏、秋、冬四个季节近滨区B类站分布范围分别与10～30m，10～20m，10～20m，20—40m的等深线区域相吻合，其范围的季节变化与黄东海水动力条件的季节变化密切相关。利用悬浮物垂向浓度模型可以由已知的海水表层浓度计算得到不同水层的悬浮物浓度，其有效性检验和拟合结果检验表明，该模型置信度较高，且能够更为有效的预报海水中、上层水体的悬浮物浓度值。

Based on the observed data （4813 sets） of suspended sediment concentration （SSC） collected in 24 cruises in the Yellow Sea and East China Sea from 1959 to 2006, the characteristics and the vertical distribution of SSC in the seas are studied. Regression equations for the vertical distribution of SSC in certain sea area and season are established by using correlation analysis and regression analysis. specific The results show that the vertical SSC has obvious seasonal variability, high in winter and spring but low in summer and autumn. The correlation between the relative water depth and SSC is pretty dose. However, the correlation between the water depth and the vertical gradient of SSC presents big in the Yangtze River estuary and Hangzhou Bay （type A）, moderate in inshore area parallel to the coastline from the Northern Jiangsu to Fujian coast （type B）, and small in other offshore area （type C）. The areas of type B in spring, summer, autumn and winter are consistent with the ranges between 10 - 30m, 10 - 20m, 10 - 20m, 20 - 40m isobath, respectively. The seasonal variation of the areas is closely related to the seasonal change of hydrodynamic condition in these areas. According to regression equations of vertical distribution of SSC, the SSC at any depth can be estimated if the SSC at surface layer is known. The validation tests on these equations show high confidence scores, and the estimated results of SSC indicate that these equations are more reliable in predicting the SSC at upper and intermediate water layers.