基于MODIS数据的伊洛河流域地表蒸散空间和年内变化特征  

Spatial Distribution and Seasonal Variation of Evapotranspiration in Yiluo River Basin Based on MODIS Data

作　　者：王万同[1,2] 钱乐祥[3] 

机构地区：[1]河南大学环境与规划学院,开封475001 [2]中国科学院地理科学与资源研究所,北京100101 [3]广州大学地理科学学院.广州510006

出　　处：《资源科学》2012年第8期1582-1590,共9页Resources Science

基　　金：省部共建黄河中下游数字地理技术教育部重点实验室开放基金项目(编号:GTYR2011001)

摘　　要：MODIS数据具备较好的时间分辨率,是目前模拟监测区域尺度地表能量与水分变化比较理想的数据源。SEBS模型理论基础坚实、区域应用限制低、反演结果较为合理准确,因此得到广泛应用。利用伊洛河流域2002年、2008年四季典型日(8d)的MODIS数据,采用结合DEM数据改进后的SEBS模型,对伊洛河流域地表蒸散进行了估算,分析了地表蒸散的空间格局和年内变化特征。结果表明:研究区地表蒸散空间分布具有明显的地域性差异,呈现出南部高、北部低,山区高、河谷低,南北梯度大的空间分布特点,区域分布不均衡;年内蒸散量的变化呈单峰趋势,季节性变化显著,下游平原区受供水条件影响差异较大。The Moderate Resolution Imaging Spectroradiometer （MODIS） data has good time resolution and is the ideal data source for simulating monitored region-scale changes in surface energy and water resources at present. SEBS （Surface Energy Balance System） model has been widely applied for its solid theoretical foundation, low limits for regional application and more reasonable and accurate inversion results. However, because the impact of terrain is not taken into consideration by SEBS model, errors occur in inversion results of mountain area with complex terrain. The research region, Yiluo river basin, has complex surface land cover types, so to make SEBS model more applicative this research has made some improvements to SEBS model based on the DEM data. After that, based on these foundations, this paper has estimated the surface evapotranspiration in Yiluo basin and analyzed the spatial distribution and seasonal variation of surface evapotranspiration with MODIS data of four-season typical days （8d） of Yiluo River Basin in 2002 and 2008 and the improved SEBS model. The results show that： 1） The inversion results of improved SEBS model are more close to the surface measure data than the non-improved model, indicating that the improved SEBS model is more accurate. Evapotranspiration increases in large scale and smoothly at an elevation less than 1000m and in small scale above 1000m. Surface evapotranspiration is evidently influenced by slope and exposure, max evapotranspiration value on southern slope; 2） The spatial distribution of surface evapotranspiration in the study area has significantly uneven regional differences. Changes in the evapotranspiration during the year show a single peak trend and significant seasonal variations, but downstream plain areas affected by the water conditions are quite different; 3） The improved SEBS model has certain application in Yiluo basin and can achieve spatio-temporal pattern of macroscopic surface energy and water resources distribution rapidly and visually,

关 键 词：MODIS SEBS模型 地表蒸散 空间分布 年内变化 伊洛河流域 

分 类 号：P426.2[天文地球—大气科学及气象学]