湖泊水环境指标的超光谱响应特征分析

为了探索湖泊水质遥感的可能性，以我国三大富营养化湖泊之一的太湖为研究对象，进行了冬夏二季太湖水面反射光谱测量与水质采样分析同步试验．对试验结果进行了统计分析．结果表明：（1）高锰酸盐指数与叶绿素浓度具有很好的相关性；(2)夏季太湖北部水面反射率主要反映叶绿素浓度的影响，可以用线性摸型来表示，以700nm以上波段体现叶绿素散射作用最为明显；(3)冬季太湖水面反射率主要反映悬浮物浓度的影响．可以用对数线性模型来表示(若仅考虑悬浮物浓度小于100mg/L区域．用线性模型更好些)，悬浮物散射作用响应的液长范围比较宽，以500nm～800nm比较明显，优势波长随着悬浮物浓度的增加而右移，给出了不同波长水面反射率与水环境指标的统计关系模型。

ANALYSIS ON THE ULTRA-SPECTRAL CHARACTERISTICS OF WATER ENVIRONMENTAL PARAMETERS ABOUT LAKE

For studying the possibility of detecting water quality by remote sensing, simultaneous field experiments at Taihu Lake (one of the three famous eutrophic lake in China) were made in winter and summer to measure the reflected light spectra on water and to get water samples for chemical analysis. Statistical analysis with experiment data shows that (1) there is good correlation between COD Mn and chlorophyll a concentration;(2)in summer, north Taihu Lake, the reflectivity spectra of light on water is affected mainly by chlorophyll a concentration, which can be expressed by a liner correlation model and it is most obvious at wavelengths larger than 700nm;(3)in winter, the reflectivity spectra of light on water is affected mainly by suspended substance concentration in a wide wavelengh range, which can be expressed by a log liner correlation model or by a liner correlation model more suitably if only the suspended substance concentration less than 100mg/L is considered, and it is more obvious at wavelengths between 500-800nm.The statistical models about lake are made between the surface spectral reflectivity at different wavelengths and the water quality parameters.