基于改进的M指标的库布齐沙漠沙丘潜在活性评价  

Evaluation of Dunes Potential Activity Based on Improved M Index:A Case Study of Hobq Desert

作　　者：管超[1] 哈斯额尔敦[1] 陶彬彬[1] 刘丹[1] 周炎广 

机构地区：[1]北京师范大学资源学院,北京100875

出　　处：《沙漠与绿洲气象》2016年第3期21-29,共9页Desert and Oasis Meteorology

基　　金：国家自然科学基金"抛物线形沙丘的动态变化研究"(41171002);国家"十二五"科技支撑计划项目(2012BAD16B0202)

摘　　要：定量评估沙丘的潜在活性程度是沙漠及沙地动态研究的基础工作。目前对于沙丘潜在活性的研究主要是通过Lancaster给出的M指标(M=W/(P/ET)),然而针对我国地形复杂、气候多变,尤其西北干旱地区,此方法与实际情况有较大出入。本文以库布齐沙漠为例采用SEBS模型代替Thornthwaite方法计算蒸散量,并将年蒸散分为4部分代表4个季节计算,以提高蒸散量的精度,并结合地表粗糙度、NDVI、降水、风速等数据利用模糊模型提取各季沙丘潜在活性指数的区域分异,最后结合地貌分类图给出潜在活性的新分级标准。经验证明基于模糊模型的沙丘潜在活性评价可以综合多种影响因素,符合我国气候、地形条件下的真实状况,提高评价精度,同时也指出Lancaster的M指标并不适合我国的自然条件。That quantifiable assess of the dunes activity is essential of the dynamic research of desert. At present, using the index M（M=W/（P/ET）） given by Lancaster is a primary study method of dunes activity. However, considered complicated landforms and variable climate, especially in the arid environment in the northwest of China, this method has great gap to the actual situation. Taking the Hobq Desert as an example, we replace SEBS model of Thornthwaite model to calculate the surface evapotranspiration. In order to improve accuracy we classified the annual evapotranspiration into four parts based on four seasons. Meanwhile taking advantage of the fuzzy model containing a range of factors, such as surface roughness, NDVI, precipitation, wind speed and other data, we extracted the regional differentiation of dunes activity index in those seasons. Finally, combining with geomorphologic map, we complished a new activity grading standard. It has been proven that this model standard, based on fuzzy model can composite a series of influence factors, is gearing to China actual situation. In a word, the fuzzy model improves the accuracy of assessment and the Lancaster＇s M Index is not suitable for China.

关 键 词：沙丘潜在活性 SEBS模型 模糊模型 

分 类 号：X144[环境科学与工程—环境科学]