近岸Ⅱ类水体表层悬浮泥沙浓度遥感模式研究进展

因为具有明显的时间与空间分辨率优势,遥感数据成为近岸Ⅱ类水体悬浮泥沙浓度(SSC)信息提取研究的重要数据源之一.悬浮泥沙遥感信息提取的现状可归纳为:(1)建立近岸Ⅱ类水体SSC遥感模式的方法有三种类型,分别是基于地面光谱与SSC测量的反射率反演方法、基于图像信息法和基于大气辐射传输理论模型法;(2)基于地面测量的反射率反演方法属于理论与经验相结合的方法,也是目前用于SSC定量化遥感模式研究的常用方法.其数学表达形式包括线性关系式、对数关系式、负指数关系式、Gordon模式和综合模式等;(3)到目前为止已有的Ⅱ类水体SSC遥感模式适用性方面还不理想,远未达到与试验室分析相匹配的精度.文章认为:加强地面水文光谱实验研究,建立多光谱SSC定量模式,以高分辨率和高光谱遥感融合数据为基础的SSC定量遥感是今后该方向发展趋势.

Progress on suspended sediment concentration remote sensing in nearshore case 2 waters

Remote sensing data are among the most important data sources for monitoring and extracting suspended sediment concentration(SSC) in near-shore coastal case 2 waters for its high spatial resolution and temporal advantage.The status of SSC extraction from remote sensing imageries may be summarized as follows.(1) Broadly speaking,SSC remote sensing modeling techniques fall into three categories. They are reflectance inversion methods based on ground spectral measurement against SSC,methods based on atmospheric corrections,and atmospheric propagation model based SSC modeling methods,respectively.(2) The ground reflectance inversion methods for SSC are of a combination of theory and experience,which are employed intensively.The empirical mathematic expressions between reflectance and SSC are in one of the forms of linear,logarithmic,negative exponential,Gordon relation or combinations of previous forms.(3)Available SSC models so far are not satisfied due to their incomparable accuracy to the SSC measured from in situ bottled samples.The authors believe that hydrological spectra study should be strengthened in order to establish a SSC model relating to multiple spectra.The trend for SSC inversion with remote sensed data is the application of fused images with both high spatial and spectral resolution.