春季太湖叶绿素a浓度的光谱估算与分析评价

2011年3月27日于太湖梅梁湾和湖心区域进行光谱数据采集,同步水质理化分析数据得到叶绿素a浓度区间为4.99μg/L～31.06μg/L。基于较低叶绿素a浓度水平的实测光谱数据及同步的理化分析数据分别采用二波段模型、光谱反射率一阶微分模型、反射峰位置模型、三波段模型和四波段模型对梅梁湾和湖心区域的叶绿素a浓度进行建模遥感估算。5个模型的回归分析结果对应R2分别为0.775,0.811,0.786,0.826和0.846,RMSE分别为4.02μg/L,3.52μg/L,3.82μg/L,3.44μg/L和3.24μg/L。并针对春季较低叶绿素a浓度水平下的光谱估算模型在应用价值和精度方面做了比较评价。

Estimation and Evaluation of Chlorophyll-a Concentration in Taihu Lake in Spring

Based on the data collected in the Meiliang bay and central region in Taihu Lake on March 27th,2011,we obtained the hyperspectral reflectance and chlorophyll-a concentration data.The concentration of chlorophyll-a of the 54 sampling points varies from 4.99μg/L to 31.05μg/L.By using the two-band-model,first-derivative method,reflectance peak position method,three-band-model and four-band-model,the concentration of the chlorophyll-a was estimated,and concentration was relatively low.The result R2 counterparts are 0.775,0.811,0.786,0.826 and 0.846 respectively.The RMSE between measured and estimated chlorophyll-a concentration by using the model is 4.02μg/L,3.52μg/L,3.82μg/L,3.44μg/L and 3.24μg/L respectively.Finally we discussed the 5 models by analyzing and making a comparison between the estimation precision and application ability using remote sensing images.