基于高光谱遥感反射率的总氮总磷的反演

Deriving Concentration of TN,TP based on Hyper Spectral Reflectivity

基于2005年4～10月实测高光谱数据,通过微分法和波段比值法对室内水样分析结果中的总氮和总磷浓度进行反演。结果表明:以1nm为间隔的微分法中455nm处的微分值对总氮浓度较为敏感,最大负相关达到-0.857,而最大正相关为波段比值(1015/528nm)的0.803,利用上述两个因子作为自变量进行多元回归,得到总氮最佳反演模型。该模型绝对误差为0.16,实测值与预测值之间R2为0.839;波段比值(671nm/680nm)对总磷浓度较为敏感,达到最大负相关-0.889,选用其作为自变量进行二次多项式回归,得到总磷最佳反演模型,该模型绝对误差为0.003,实测值与预测值之间R2为0.934。

Inversion of TN and TP＇ concentration through the method of derivative and wavelength ratio on the basis of the hyper spectral data which was measured from April to October in 2005. The results indicate that differential method in the lnm intervals 455 nm differential values of TN concentration in more sensi tive,maximum Negative correlation coefficient is -0. 857, maximum positive correlation coefficient is wavelength ratio＇s（1 015/528 nm）0. 803. Using these two factors as variables for multiple regression,the best inverse model of TN was got, the absolute error of model is 0.16, between measured and predicted val ues of Rz is 0. 839. The band ratio （671/680 nm）of TP concentration is more sensitive,the maximum Nega tive correlation coefficient is -0. 889,because the variables are selected as a second polynomial regression, the best inverse model of TP was got. The absolute error of the model is 0. 003 ,between measured and pre dicted values of R2 is 0. 934.