植被参数变化对沙尘起沙影响机理的数值模拟

分析了叶面积指数和植被覆盖变化对沙尘暴起沙过程的影响机理。在一个集成的沙尘数值模拟预报系统中,将模拟区域的叶面积指数分成了0,0.5,3.0和卫星反演的实测值4种,结果表明,叶面积指数对沙尘的数值模拟有较大的影响,利用卫星反演的叶面积指数计算沙尘浓度时,沙尘浓度的变化介于叶面积指数为0~0.5之间。将植被覆盖度数据分成0,0.2和卫星反演的实测值3个类型。当植被覆盖度都为0时,沙尘浓度最大;当植被覆盖度为0.2时,沙尘浓度出现的范围明显减少。

The Impact of Variations of Underlying Surface and Vegetation Index on Numerical Simulation of Dust Emission

The mechanism of impacts of leaf area index and the change in vegetation coverage on the process of dust emission is analyzed in this paper.In an integrated numerical simulation and forecast system of dust storms,the leaf area index in a simulated region is grouped into 0,0.5,3.0 and the measured value of satellite inversion.The results show that the leaf area index influences the numerical simulation of sand storms.The change of dust concentration calculated with the leaf area index of satellite inversion lies between 0~0.5.Meanwhile,the data of vegetation coverage is divided into 0,0.2 and the measured value of satellite inversion.The dust concentration is the highest while the coverage rate of vegetation is 0,and the dust concentration is low when the rate is 0.2.