干旱区生态环境知识资源中心

In arid and semiarid regions, development of vegetation is highly limited by scare of water. As a result, the vegetation cover fraction of high water consumption plants is less than that of low water consumption plants. Models in accounting for the relationship between consumption of water and vegetation index can yield basic information in assessment the water balance behavior in arid and semiarid regions. As a case study in Mu Us Desert, in China, leaf transpiration rates of several typical species and leaf area index (LAI) are measured by potometer and LAI Plant Canopy Analyzer respectively. The data is used to analyze the characteristics and controls of desert vegetation transpiration. A statistical model of vegetation water consumption is proposed based on the correlation between leaf area index and leaf transpiration rates. According to the patterns of time varying consumption of water for different plants, an annual transpiration model with average maximum LAI is developed. (C) 2011 Published by Elsevier B. V. Selection and/or peer-review under responsibility of School of Environment, Beijing Normal University.