珠江口水体叶绿素a浓度高光谱反演研究

Study on Retrieval of Chlorophyll a Concentration in the Waters of Pearl River Estuary by Hyperspectral Technology

对珠江口水体进行了现场光谱测量和同步的水质采样分析,发现695nm处的一阶导数光谱数据对叶绿素a浓度有很好的指示作用,由此建立了基于695nm处一阶导数光谱数据的叶绿素a浓度的线性模式、二次多项式模式、三次多项式模式和指数模式。两次实验的结果表明:指数模式的R2(确定系数)为0.7584,预测平均相对误差为26.7239,是估算珠江口水体叶绿素a的最佳的模式。

The in-situ spectrum was measured with simultaneous sampling and analysis of water quality parameters. It is discovered that the first derivative spectrum at 695 nm is better factor to denote chlorophyll a concentration. Therefore several models including linear model, exponent model, quadratic polynomial and cubic polynomial model between chlorophyll a concentration and the first derivative spectrum at 695 nm were established. The result indicates that the R2 of the exponential is 0.7584 and the average relative error is 26.7239, which is the best one to retrieve chlorophyll a concentration.