摘要
以西北半干旱地区的内蒙古农牧交错地带锡林郭勒盟为研究区,以不同退化程度的草地为研究对象,通过叶面积指数计算各像元的动力传输粗糙度长度,以改进显热通量算法;并结合植被/土壤组分温度分别计算基于亚像元的植被/土壤的显热通量。由敏感性分析和模型验证表明,改进的显热通量算法能够提高区域尺度的能量平衡计算精度。
Sensible heat flux is a key parameter of land surface energy balance and water cycle. This paper selects different degraded grasslands in Inner Mongolia grassland region as study objects. In view of the difference between heat transfer of soil and vegetation, component temperatures are inversed using thermal infrared bands of MODIS（Moderate Resolution Imaging Spectroradiometer）. Then the sensible heat flux of soil and vegetation can be estimated separately. Moreover, considering that leaf area index can reflect the structure and condition of vegetation better, leaf area index is inversed using visible and near infrared bands of MODIS by means of Ra - Go mixed model in this paper. It is related to the vegetation geometry roughness. Therefore, leaf area index is introduced to compute the dynamic transfer roughness length so that the algorithm computing the sensible heat flux can be improved. It will improve the precision of energy balance computation on the regional scale.
出处
《地理与地理信息科学》
CSCD
北大核心
2007年第1期36-38,共3页
Geography and Geo-Information Science
基金
国家自然科学基金项目(40501051)
博士后基金项目(2005037314)
国家重点基础研究发展规划项目(G2000077907)
关键词
显热通量
叶面积指数
动力传输粗糙度长度
能量平衡
sensible heat flux
led area index
dynamical transfer roughness length
energy balance
