Modelling Chlorophyll-a Concentration in Taihu Lake from Hyperspectral Reflectance Data
基于高光谱遥感反射比的太湖水体叶绿素a含量估算模型

The study aims to search for the hyperspectral remote sensing bands most sensitive to chlorophyll-a concentration.Through repeated measurements in Taihu Lake,a large quantity of hyperspectral reflectance data and water quality data of the Lake were obtained from June to August of 2004.Those data acquired in unfavorable or abnormal monitoring conditions were removed from the dataset.The remaining ones were analyzed to calculate water-leaving radiance and reflectance of water in Taihu Lake.Chlorophyll-a concentration was then regressed against the reflectance data to identify the most sensitive hyperspectral bands.The established regression model was then used to estimate chlorophyll-a concentration in the Lake.Finally,accuracy of the model was assessed using other independent data.The result generated with the given monitoring method indicates that there are two reflectance peaks at 719nm & 725nm.Of them,the one at 719nm is more enhanced and stable.Through comparative analysis it is found that hyperspectral reflectance at these two peaks can improve the accuracy of estimating chlorophyll-a.Moreover,the accuracy of estimation is the highest using the ratio R_(719)/R_(670) as the independent variable in the linear model.