基于实测数据的鄱阳湖悬浮泥沙粒度遥感反演模式分析

Models of Remote Sensing Retrieval of Suspended Sediment Particle Size in the Poyang Lake Based on Measured Spectral Reflectance Data

水体悬浮泥沙粒度是重要的水质参数之一,影响着水体的遥感反射率。研究两者之间的关系对于内陆湖泊水环境遥感监测具有重要意义。基于鄱阳湖实测数据,采用相关分析方法,用不同数学模型进行鄱阳湖悬浮泥沙粒度反演研究。研究结果表明:(1)浑浊区适合采用体积百分比众数粒径建立反演模型,清水区适合采用数量百分比中值粒径建立反演模型;(2)浑浊区悬沙粒度的敏感单波段是环境卫星Ⅳ波段,在清水区悬沙粒度的敏感单波段有环境卫星Ⅱ和Ⅲ波段,而环境卫星Ⅱ,Ⅲ波段比组合是整个研究区水域的敏感波段;(3)单波段反演模型中,幂函数适用于鄱阳湖粒度遥感反演;波段比反演模型中,多项式模型适于鄱阳湖粒度遥感反演。

Particle size of suspended sediment,as an important parameter reflecting water quality,has an influence on the spectral reflectance of water. Study of the relationship between particle size and reflectance is of great significance to water environment monitoring in inland lakes. In this paper,the suspended sediment particle size of the Poyang Lake was retrieved using different mathematical models based on correlation analysis according to measured spectral reflectance data. Results show that: 1) volume percentage median diameter is suitable for the retrieval model for turbid area; while quantity percentage median diameter is suitable for clear water; 2) in turbid area,single band Ⅳ is the sensitive wave band; whereas in clear water,single band Ⅱ and single band Ⅲ are sensitive wave bands. In addition,the reflectance ratio of band Ⅱ to band Ⅲ is the sensitive wave band in the whole study area; 3) in the retrieval model of single band reflectance,power function is suitable for the retrieval of suspended sediment particle size in the Poyang lake; while in the model of band reflectance ratio,polynomial model is the most suitable.