塔里木河荒漠植被光谱可分性模拟  

Spectral Discrimination of Desert Vegetation in the Tarim River Basin

作　　者：赵金[1,2] 陈曦[1] 古丽·加帕尔[1,2] 马忠国[1,2] 常存[1,2] 

机构地区：[1]中国科学院新疆生态与地理研究所绿洲生态与荒漠环境重点实验室,新疆乌鲁木齐830011 [2]中国科学院研究生院,北京100049

出　　处：《中国沙漠》2009年第2期270-278,385,共10页Journal of Desert Research

基　　金：“973”项目(2009CB421301);国家支撑项目(2007BAH12B03);国家自然科学基金项目(40801146;40730633;40571030)共同资助

摘　　要：以塔里木河典型植被为研究对象,分析胡杨、芦苇叶片及柽柳冠层的可分性,并计算背景的影响。首先用ASD光谱仪测新鲜叶片光谱,找出光谱特征点;然后模拟EO-1高光谱数据和TM多光谱数据;最后植被与土壤光谱按比例混合,分析背景的影响。以上三步分别计算植被指数（VI）。结果显示：叶片光谱特征位置430 nm、670nm、750 nm附近,黄边斜率和红外平台平均高度,1 080～1 280 nm、1 430～1 650 nm能够区分塔里木河流域3个主要植被类型。模拟的EO-1波谱保持了控制波形的10个特征,TM只有绿反射峰和红吸收谷、近红外1个反射峰3个特征,大部分特征都消失了。植被指数显示（R680-R500）/R750、（R680-R550）/R705、R1430＋…＋R1650、D712/D688能够区分3类,且指数值差异较大,为绿峰、红谷和近红外波峰的组合;模拟的EO-1数据（R680-R500）/R750、（R680-R550）/R705、R1430＋…＋R1650能分别区分植被,TM多波谱数据不能有效区分植被。The spectral discrimination of typical vegetation in the Tarim river basin and the effect of back- ground were analyzed in the paper. Firstly, an ASD Spectral Measurement Instrument was used to measure the fresh leaf reflectance, by which the spectral characteristic points were determined. Then we simulated the EO-1 hyperion spectra and TM spectra with leaf spectrum. Finally, the spectra of vegetation and soil were linear mixed. In these three processes the vegetation indices were calculated. Results showed that vegetation may be discriminated by leaf spectral characteristic positions, which including blue band 430 nm, red band 670 nm, near infrared 750 nm, yellow edge gradient, infrared platform mean height, water absorb band 1 080-1 280 nm and 1 430-1 650 nm. The simulated EO-1 spectra kept the ten features of controlling spectral shape in leaf, on the contrary, the simulated TM only retained the green reflective peak, red absorb hollow and near infrared reflective peak, most of features disappeared. Vegetation indices demonstrated that （R68--R500 ）/R750, （R680- R550 ）/R705, R1430＋…＋R1650, D712/D688 may be different vegetation forms in the Tarim river basin, which are combination of green peak, red hollow and near infrared.

关 键 词：荒漠植被 高光谱 多光谱 植被指数 干旱区 

分 类 号：X87[环境科学与工程—环境工程]