基于GIS的坡耕地数字高程模型的建立与应用  

Establishment and application of DEM for loess slope land based on GIS

作　　者：赵龙山[1] 张青峰[1] 梁心蓝[1] 曹伟鹏[1] 吴发启[1] 

机构地区：[1]西北农林科技大学资源环境学院,杨凌712100

出　　处：《农业工程学报》2010年第11期317-322,共6页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目(40871133);国家重点基础研究发展"973"计划(2007CB407201)

摘　　要：微地形是描述地表起伏状态的重要指标,也是地表径流和土壤侵蚀过程的重要影响因子。在微尺度上建立了不同耕作措施下黄土坡耕地的数字高程模型(DEM),并对其空间特征进行了分析。结果表明,利用反距离加权插值法建立的微DEM模型能正确地再现坡耕地地表形态,利用其派生的微坡度、微坡向数据可作为研究土壤侵蚀空间差异的重要因子;微坡度分布特征与耕作措施密切相关,对于人工锄耕(CH)和人工掏挖(TW)措施,微坡度栅格统计数随着微坡度的增大呈先增大,后减小的变化趋势,而等高耕作(DG)措施下微坡度栅格统计数随着微坡度的增大而增大;TW,CH和DG坡面微坡向的栅格统计数具有明显的差异,坡度对微坡向的分布影响明显;利用微DEM计算的地表侵蚀量能够反映出坡面侵蚀的大小。为研究微地形条件下土壤侵蚀过程提供了数据资料,也为进一步研究微地形条件下土壤侵蚀机理的特征提供了参考。The paper established a digital elevation model（DEM） of loess slope land under different tillage conditions on the micro-scale,and DEM spatial characteristic was analyzed. The results showed that micro-DEM model established by the method of inverse distance weighted interpolation could correctly reproduce the surface morphology of sloping land. Derived micro-slope and micro-aspect values could be taken as important factors in studying spatial difference of soil erosion. Micro-slope distribution characteristics and tillage measures were closely related. As for artificial hoe and contour measures,grid statistic figures of micro-slope increased at initial then decreased with increasing of micro-slope,while grid statistic figures of micro-slope increased with increasing of micro-slope under the measures of artificial dig. Grid statistic figures of micro-aspect had obviously differences among measures of contour,artificial hoe and artificial dig,and slope had a significant effect on the distribution of micro-aspect. Surface erosion calculated using the micro-DEM could reflect the size of slope surface erosion. This study not only provides data information for the study of soil erosion process under the micro-topographic condition,but also lies the foundation of further study in the mechanism of soil erosion under the micro-topographic condition.

关 键 词：侵蚀 地理信息系统(GIS) 地形 黄土坡耕地 耕作措施 微地形 数字高程模型 

分 类 号：S157.1[农业科学—土壤学]