中文摘要：

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（Kd）特征、各影响因子对配的贡献率以及虬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虬以571nm为分界点，在整个可见光波长范围内（400～700nm）主要呈现2种变化趋势．第1种，在〈571nm波长范围内，配随着波长的增加呈现指数形式衰减，第2种，在〉571nm波长范围内，虬表现为波动形式；在400—700nm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，虬形成的“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．

英文摘要：

According to the optical property data measured in Taihu Lake at October and November 2006, the characteristics of the diffuse attenuation coefficient（ Kd ）, the contribution of each factor effecting on Kd and the effect of Kd on the aquatic ecology environment were analyzed. The results indicate that, the diffuse attenuation coefficient Kd of Taihu Lake has two main trends in the whole visible wavelength range （400-700 nm）. The first type is that, Kd decreases with the wavelengths by exponential style in the range of less than 571 nm wavelengths, and the second type is that, Kd is in the form of fluctuations in the range of larger than 571 nm wavelengths. In the range of 400- 700 nm wavelength, the absorption coefficient of pigment particles is the first contributors of diffuse attenuation coefficient. Non-pigment particles absorption and scattering coefficients is the second contributor, and the rate of contribution of yellow substance is the smallest. The Kd of Taihu Lake determines the light factor of the Taihu water ecosystem. The ＂water window＂ shaped by the Kd provides the light base for different kinds of ecosystem and the appearance of Microcystis aentginosa which is the preponderant algae in the ＂algal blooms＂ phenomenon.