2000～2008年内蒙古中部地区土壤风蚀危险度评价

选择内蒙古中部为研究区,以地理信息系统技术与层次分析法为依托,在深入调研风蚀驱动因子的基础上,构建了一个驱动因子相对全面并且实践可行的土壤风蚀危险度模型;基于该模型,综合长时间序列的遥感数据、地面气象台站观测数据,对研究区2000~2008年土壤风蚀危险度的空间分布格局、变化动态及其驱动机制进行了分析。结果表明:在内蒙古中部地区,从东南到西北土壤风蚀危险度呈现逐渐增强的趋势,不同的风蚀危险等级区有着不一样的主导控制因子;在2000~2008年期间,区域土壤风蚀危险程度总体呈现下降趋势;2000年以来风场强度的持续下降及植被NDVI的持续上升是促使区域土壤风蚀危险度下降的控制因子,而气候干燥度在2005年的大幅上升则是当年区域土壤风蚀危险度上升的控制因素。

Soil Wind Erosion Risk Assessment in the Middle Part of Inner Mongolia Plateau During 2000 to 2008

The middle part of Inner Mongolia Plateau was got the very attention of many researchers and local governments because of its important geographical position.One of the most important reasons is that it is the region of serious wind erosion.And for this reason,this area was chosen as case study region to evaluate the soil wind erosion.In this paper,a wind erosion risk evaluation model was established by applying of geography information technology(GIS) and analytic hierarchy process(AHP) method to assess the wind erosion risk in this region.A series of wind erosion risk datasets from 2000 to 2008 were then gathered in this study region to analyze the spatial distribution pattern and the temporal process of wind erosion risk in detail.Then,the driving mechanism in wind erosion process,including vegetation coverage,land use,meteorological factors,were analyzed deeply based on the common senses and existing wind erosion model.The main convolutions are as follows: First,from the southeast to the northwest,the wind erosion risk of study area gradually increased.Except the year of 2005,the general trend of wind erosion risk was falling during the whole study period.Second,the change of land system had little impacts on soil erosion risk because of the slight changes of land use and land cover in whole study period.Third,the continuous decline of wind energy intensity and the stable rising of NDVI were the leading factors to decline the wind erosion risk during 2000 to 2008;while the increase of soil dryness is the key driving forces of all 6 factors to increase wind erosion risk in 2005.