浙江近海夏季表层悬浮体浓度和浊度特征及其在遥感解译中的应用

Characteristics of Suspended Sediment Concentration and Water Turbidity in Zhejiang Offshore Area and Its Application in Remote Sensing Interpretation

摘要: 浙江近海悬浮体浓度(SSC)和水体浊度(WT)空间分布差异巨大，利用遥感反演的方法获得SSC误差较大。根据2023年夏季浙江近海水体大量同步实测数据，对SSC和WT分布特征、影响因素进行了分析。结果表明，表层水体的温度对SSC和WT影响不大，盐度与二者均为负相关，细颗粒悬浮物具有较高SSC和WT。在杭州湾至象山港海域，二者与叶绿素a含量呈负相关，而在象山港以南海域，SSC和WT大幅减小，水体中生物颗粒的含量对浊度的大小有很大的影响。分为杭州湾至象山港海域、象山港至台州湾海域和台州湾以南海域三个区域，根据线性回归分析结果建立浙江近海三个区域的SSC和WT换算关系并进行了验证。中部的象山港到台州湾海域SST和WT在适当的范围内，二者的换算关系精确度最高。在高SST悬浮体浓度或高生产力海域，相关性变差。实际使用中应当注意。

Abstract: The spatial distribution of suspended sediments concentration (SSC) and water turbidity (WT) in the offshore of Zhejiang varies greatly, and the errors in obtaining SSC are large using remote sensing inversion methods. Based on a large number of simultaneous measured data of Zhejiang offshore water body in summer 2023, the distribution characteristics of SSC and WT, and the influencing factors were analyzed. The results show that the temperature of the surface water body has little influence on the SSC and WT, salinity is negatively correlated with both, and fine particles of suspended matter have high SSC and WT. In the waters from Hangzhou Bay to Xiangshangang Bay, both are negatively correlated with the chlorophyll a content, whereas in the waters south of Xiangshangang Bay, the SSC and WT are greatly reduced, and the content of biomass particles in the water body has a great influence on the magnitude of turbidity. Three regions, namely, Hangzhou Bay to Xiangshanggang Bay, Xiangshangang Bay to Taizhou Bay, and south of Taizhou Bay were divided in the study area, and the SSC and WT conversion relationships of the three areas were established and verified based on the results of linear regression analysis. The SST and WT in the central Zhejiang offshore sea area were in the appropriate range, and the accuracy of the conversion relationship between the two was the highest. The correlation becomes not significant at high SST suspended sediments concentration or high productivity waters. This should be noted in practical use.