非均匀陆面条件下区域蒸散量计算的遥感模型

THE REMOTE SENSING MODEL FOR REGIONAL EVAPOTRANSPIRATION ESTIMATION OVER HETEROGENEOUS LANDSCAPE

中文关键词:  非均匀陆面条件  区域蒸散  遥感模型  植被覆盖度

英文关键词:Heterogeneous landscape  Regional evapotranspiration  Remote sensing model  Vegetation fraction

中文摘要:

      非均匀陆面条件下的区域蒸散计算是一个复杂的问题.文中首先在利用遥感资料求取地表特征参数(如植被覆盖度、地表反照率等)的基础上,建立了裸露地表条件下的裸土蒸发和全植被覆盖条件下植被蒸腾计算模型,然后结合植被覆盖度(植被的垂直投影面积与单位面积之比)给出非均匀陆面条件下的区域蒸散计算方法.实测资料验算表明该模型具有较高的计算精度.文章最后利用该模型对中国北方地区的蒸散量进行了计算,并对该研究区蒸散的特点进行了分析.

英文摘要:

      It is a very complicated problem to estimate evapot ranspiration over natural land surface.In this paper,the evapot ranspiration estimation models for dense vegetation and bare soil are presented based on the information of surface parameters firstly:These models are based on information from surface properties like land cover and surface albedo.Then by use of vegetation fraction(the ratio of vegetation projective area to unit area),the regional evapot ranspiration estimation model over the heterogeneous landscape is proposed.As a result of case study over North China,it shows that the accuracy of evapotranspiration estimation is higher and the features of evapot ranspiration over North China are discussed.The validation shows that this model provides good estimation of daily regional ET.