基于生物光学模型的巢湖后向散射概率估算  

Estimating of Backscattering Rate in Lake Chaohu Based on Bio-optical Model

作　　者：刘忠华[1] 李云梅[1] 吕恒[1] 徐祎凡[1] 徐昕[1] 黄家柱[1] 

机构地区：[1]南京师范大学虚拟地理环境教育部重点实验室,南京210046

出　　处：《环境科学》2011年第2期464-471,共8页Environmental Science

基　　金：国家科技支撑计划项目(2008BAC34B05);国家自然科学基金项目(40971215);江苏省研究生培养创新工程项目(CX10B_392Z)

摘　　要：后向散射概率是水面光谱的重要影响因素.利用2009年6月巢湖实测数据,基于生物光学模型在近红外波段的简化原理,通过2个近红外波段构建巢湖后向散射概率估算模型.结果表明,巢湖后向散射概率最大值为0.059,最小值为0.001 4,均值为0.023 6,巢湖西部后向散射概率总体上大于东部,并且西部的空间差异性要大于东部.此外,利用后向散射概率计算出各样点的颗粒物折射指数,根据折射指数的变化范围划分巢湖水体颗粒物的主导因子,结果表明,74%的样点属于无机颗粒物主导型,18.5%的样点属于藻类颗粒物和无机颗粒物共同主导型,而藻类颗粒物主导的样点仅占总样点的7.4%,说明巢湖水体的后向散射特性主要受无机颗粒物影响,而藻类颗粒物的影响相对较小.Backscattering rate is the important factor of above water spectra.A bio-optical model simplified in near-infrared bands was constructed to estimate backscattering rate in Lake Chaohu by using the in-situ data measured in June 2009.The results show that the maximum value of backscattering rate in Lake Chaohu is 0.059,the minimum value is 0.001 4 and the mean value is 0.023 6.Backscattering rate and spatial differences in the west of Lake Chaohu are all greater than that in the east.In addition,particle refractive index of each sampling site was calculated by using backscattering rate.The dominant factors of in-water particles were determined according to the change scopes of refractive index.The results show that 74% of all sampling sites are dominated by inorganic particles,18.5% of all sampling sites are dominated by both phytoplankton and inorganic particles,and the rest of sampling sites which accounts only for 7.4% of all sampling sites are dominated by phytoplankton.This indicates that backscattering character of Chaohu Lake is mainly affected by inorganic particles,while the effect of algae particle is relatively small.

关 键 词：后向散射概率 生物光学模型 折射指数 单位散射系数 巢湖 

分 类 号：X524[环境科学与工程—环境工程] X87