太湖水体漫衰减系数特征及其对水生态环境影响分析

利用2006年10～11月太湖全湖不同区域光学属性的测量数据，就太湖水体漫衰减系数(K_d)特征、各影响因子对K_d的贡献率以及K_d对太湖水生态系统的影响进行分析.结果表明，太湖水体的漫衰减系数K_d以571 nm为分界点，在整个可见光波长范围内(400～700 nm)主要呈现2种变化趋势.第1种，在<571 nm波长范围内，K_d随着波长的增加呈现指数形式衰减，第2种，在>571 nm波长范围内，K_d表现为波动形式；在400～700 nm波长范围内，色素颗粒物的吸收系数是漫衰减系数第一贡献者，非色素颗粒物吸收系数和散射系数处于第二贡献者地位，而黄质吸收系数的贡献率相对最小；太湖水体漫衰减系数决定了太湖水生态系统中的光生态因子，K_d形成的“水体窗口”影响了太湖水域不同类型生态系统的形成，并为太湖“水华”的优势藻类铜绿微囊藻的出现提供了水下光场依据.

Characteristics of the Diffuse Attenuation Coefficient and Its Impact on Aquatic Ecology Environment

According to the optical property data measured in Taihu Lake at October and November 2006,the characteristics of the diffuse attenuation coefficient(K_d),the contribution of each factor effecting on K_d and the effect of K_d on the aquatic ecology environment were analyzed.The results indicate that,the diffuse attenuation coefficient K_d of Taihu Lake has two main trends in the whole visible wavelength range(400-700 nm).The first type is that,K_d decreases with the wavelengths by exponential style in the r...