基于对内陆水体叶绿素a、悬浮物、溶解有机物与纯水的固有光学特性分析和三波段模型的理论,利用太湖实测的水面高光谱遥感数据波段组合,进行迭代优化,得到与叶绿素浓度密切相关而受悬浮物与黄色物质影响小的最优波段组合模型。其中春季最后以[Rrs-1(677)-Rrs-1(696)]×Rrs(754)为因子建立模型,决定系数和均方根误差分别为0.9885、1.80332ug/l,验证数据的模型的均方根误差为5.8646ug/l,平均相对误差为25.5%,秋季的叶绿素浓度较高,三波段模型迭代计算中,用于去除无机悬浮物和黄色物质影响的波段不能稳定出现,为此我们补充计算了二波段模型,分别以[Rrs-1(680)-Rrs-1(710)]×Rrs(770)和R(680)-1×R(770)为因子,取得的模型决定系数和均方根误差分别为0.881,11.6322ug/l和0.883,11.52633ug/l,验证数据的均方根误差和平均相对误差为15.456ug/l,20.3%和15.684ug/l,21.4%,两种模型都能取得不错的反演效果。因此该方法可以有效地去除悬浮物和黄色物质的影响,有效地针对不同时相的特点取得较好的反演效果。
Inversion of phytoplankton chlorophyll-a concentration of inland water body is hotspot and difficult problem in water quality remote sensing.This paper provides a method to resolve this problem.Based on the characteristic spectral analysis of chlorophyll-a,suspended matter,chromatic dissolved inorganic matter and pure water molecule in inland water body,the three-band model was spectrally tuned accord with optical properties of Lake TAIHU to optimize spectral bands combination for accurate chlorophyll-a concentration estimation.Be closely related with the chlorophyll concentration of suspended solids by a yellow substance with a small impact on the optimal band combination model,in which inversion of the spring with the factor [Rrs-1(677)-Rrs-1(696)]×Rrs(754),the coefficient of determination and root mean square error were 0.9885,1.80332 ug/L.Validation of the data model,root mean square error of 5.8646ug / l,mean relative error of 25.5%.In the calculations of autumn three-band model,the band for the removal of inorganic suspended matter and yellow substances effects can not be stable,for which we have calculated the two-band model to add to,obtain two models with the factor [Rrs-1(680)-Rrs-1(710)]×Rrs(770) and R(680)-1×R(770),coefficient of determination and root mean square error of 0.881,11.6322 ug / l,and 0.883,11.52633 ug / l.Validation of the data model,root mean square error and mean relative error 15.456ug / l,20.3%,and 15.684ug/l,21.4%,the two models can achieve good inversion results.Therefore,this method can effectively remove suspended matter and yellow substance effect for different time to obtain a better inversion results.