高浑浊内河悬沙浓度的遥感估测:以中国云南金沙江下游支流为例  

Remote Sensing Estimation of Suspended Sediment Concentrations in Highly Turbid Inland River Waters: An Example from the Lower Jinsha Tributary, Yunnan, China

作　　者：S.C.Liew 吕喜玺[2] 陈平[1] 周跃[3] 朱云梅[3] 

机构地区：[1]Centre for Remote Imaging,Sensing and Processing [2]新加坡国立大学地理系 [3]昆明理工大学环境科学与工程学院,云南昆明中国650093

出　　处：《山地学报》2003年第3期378-379,共2页Mountain Research

基　　金：云南省中青年学术带头人后备人才培养基金;国立新加坡大学科研基金

摘　　要：山区土地利用和土地覆盖变化对水文过程的影响是人们关注的热点,因为它与洪水或干旱等严重的自然灾害有密切关系.一般认为,森林的清除会引起一个地区水沙量的明显增加.The impact of land use and land cover change in mountain areas on hydrological processes is a major concern, as it potentially can result in catastrophic events such as floods and droughts. It has been suggested that forest removal causes increased water and sediment yield. However, it is difficult to quantify the sediment fluxes of large river basins by ground measurements, especially in mountainous and less accessible areas. Remote sensing provides a viable option for obtaining data on the sediment loads of rivers in these areas. In this study, we developed algorithms for estimating suspended sediment concentrations (SSC) in highly turbid inland river waters from remote sensing reflectance measurements in the visible and near-infrared wavelength bands. The algorithms were calibrated using ground measurements of SSC and water reflectance spectra at tributaries of the Lower Jinsha River in Yunnan, China. The field trip was conducted in June 2002, a season of high water discharge and high sediment yield. A GER 1500 handheld spectrometer was used to acquire the reflectance spectra. Suspended sediment concentrations were measured using the standard method of water filtration. The SSC values spanned a wide range from 16 g/m3 to 13 000 g/m3. The median and average concentrations were about 800 and 1900 g/m3 respectively. The ratio of the reflectance at 800 nm and 550 nm (R800/R550) was to correlate well with SSC up to approximately 250 g/m3. The ratio R800/R550 could be fitted to the equation r = r0(1 + S/a)/(1 + S/b) where r =R800/R550, S is the suspended sediment concentration and and r0 , a, b are the fitting parameters. This equation could be inverted to obtain the SSC value from the measured reflectance in the green and the near-infrared bands. This inversion algorithm could not be used for waters with very high SSC, as the ratio R800/R550 remained approximately constant at high SSC. More than half of our sampling points fell into this category. In this case, we fitted the water reflectance sp

关 键 词：高浑浊内陆河流 悬沙浓度 金沙江 遥感 中国 云南 山区土地利用 

分 类 号：TV882.874[水利工程—水利水电工程]