甘肃张掖盆地区域蒸散量变化规律及其影响因素分析

The change of regional evapotraspiration and the influential factors in the Zhangye basin, central China

表面能量平衡系统是应用卫星对地观测的可见光、近红外和热红外波段资料,结合实测气象数据或大气模式输出数据,根据表面能量平衡原理估算不同尺度的地表大气湍流通量,从而估算地表相对蒸散的一种方法.本文将水文数据与遥感数据相结合,对张掖盆地1990-2004年间的区域蒸散量进行了估算,统计了区域蒸散的年际变化规律,并对其影响因素进行了分析.结果表明:张掖盆地的区域蒸散量呈逐年升高的趋势,这种增长趋势与黑河中游莺落峡、正义峡间的耗水量增加,张掖地区人口、GDP的增长及农田用地的增加有着良好的相关性.但最直接、最主要的因素为盆地耗水量.

Using visible and infrared satellite remote sensing data, the surface energy balance system （SEBS） is based on land surface energy balance theory combined with the in-situ meteorological data or the product of atmospheric numerical model, and estimates land surface turbulent flux and the relative evaporation at different scales. On the basis of hydrological and remote sensing data, this paper calculated the annual regional evapotranspiration （ET） of the Zhangye basin in 1990 to 2004. The interannual variability of the annual regional ET was assessed and the impact factors were analyzed in this study. The result indicated that the annual regional ET of the Zhangye basin increased gradually and it has good correlation with water consumption between the Yingluo and Zhengyi gorges in the middle stream of Heihe River. The population, GDP growth, and the increase of agricultural areas in the Zhangye basin also have affect on the ET change. Among them, the most important impact factor for the ET is the water consumption of the Zhangye basin.