摘要
为了探索太湖水体颗粒物散射的剖面分布特征,掌握水下散射变化机制,2008年11月对太湖3个不同深度的散射系数和后向散射系数分别进行观测.研究分析了它们随深度变化的特征;由衰减系数,计算出太湖水体颗粒物粒径分布函数(PSD)斜率值的剖面分布;根据散射系数与悬浮物浓度的相关关系,推算了悬浮物浓度及组成的剖面分布;根据水体折射指数,分析了不同深度水体散射系数的主导影响因子.在0、50、100 cm这3个深度处的颗粒物散射,分别有14%、17%、12%的样本是由藻类颗粒物主导的,35%、30%、34%是由无机颗粒物和非藻类有机颗粒物主导的,51%、53%、51%是由三者共同主导.结果表明,太湖水体的散射和后向散射系数随深度变化较小,不同湖区太湖水体总悬浮的浓度差异性很大,但是在不同剖面深度上差异较小,浓度差异较大的点基本上都出现在入湖河流旁,太湖水体颗粒物散射系数的主导影响因子除少数靠近入湖河流的样点外,大部分样点在不同剖面深度上差异较小.
To acquire the depth profile of suspended particle scattering coefficient and the mechanism of surface reflection, three different depths of Taihu Lake scattering coefficient and backscattering coefficient are obtained in Nov. 2008, respectively. And their characteristic variation with depth is studied. Profiling distribution of the slope of particulate size distribution （PSD） is computed by the attenuation coefficient. Profiling distribution of the concentration and composition of suspended particle is computed according the relationship between the scattering coefficient and the suspended particle concentration. Impact dominant factors on scattering coefficient of the depth of water are divided according to the range of refractive index. At the three depths（0, 50, 100 cm） , the particle scattering, with the percentage 14% , 17% , 12% of the samples are dominated by algae, respectively. 35% , 30% , 34% of the samples are dominated by inorganic particulate matter and Non-algal organic particulate matter,and 51% , 53% , 51% of the samples are dominated by the above all. The results can be concluded as： scattering and backscattering coefficient of Taihu Lake water body changes with depth slightly. The concentration of total suspended particles is of more diversity in different lake area, but there is less difference at different depths except those samples near the inflow rivers. The main factors of scattering coefficient of most aquatic scattering in Taihu Lake had little difference at different depths, except several samples beside the inflow rivers.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2010年第3期598-605,共8页
Environmental Science
基金
国家自然科学基金项目(40971215)
国家自然科学基金重点项目(40730527)
关键词
太湖
散射系数
后向散射系数
剖面分布
主导影响因子
颗粒物粒径分布函数
Taihu Lake
scattering coefficient
backscattering coefficient
profiling distribution
dominate factors
particulate size distribution （PSD）
