滇池水体总悬浮物散射系数参数化模型

Parameterization of a scattering coefficient model for Dianchi Lake,China

总悬浮物的散射系数是水体非常重要的固有光学量之一,散射系数的参数化研究,对于水体生物光学模型的构建具有非常重要的意义.2009年9月对滇池水体25个样点进行野外采样,对滇池水体水质参数、悬浮物的吸收、散射特征进行分析,并利用乘幂模型对散射系数进行参数化,分析了模型精度与色素颗粒物吸收之间的关系,进而改进乘幂模型.结果表明,在色素颗粒物吸收较强的波段,普通乘幂模型的平均相对误差为0.08,模型改进后相对误差缩小为0.02;在色素颗粒物吸收较弱的波段,会出现模型的过修正,这主要取决于色素颗粒物的吸收,因此,没有必要对乘幂模型进行修正.

The scattering coefficient of total suspended matter is an important parameter to describe a water＇s inherent optical properties. Accurate parameterization of the spectral scattering coefficient is required for bio-optical model development. In Sept. 2009,25 water samples were collected from Dianchi Lake,and the water quality,absorption characteristics and scattering coefficients were analyzed. A power model was used to parameterize the scattering coefficients. To improve the power model performance,the absorption by phytoplankton pigments was taken into account. The average relative error of the general power model was 0.08,while the modified model reduced the error in wavelengths associated with strong pigment absorption to 0.02. However,in other wavelengths where pigment absorption was low,the modification overcorrected the effects due to pigment absorption,and therefore was not necessary.