毛乌素沙地沙化土地时空动态研究

Temporal and Spatial Dynamics of Desertified Land in MU Us Sandy Land

以1990、2000、2010、2016年4期遥感影像为数据源,通过毛乌素沙地不同时期沙漠化土地面积、不同程度沙漠化土地年间转换情况以及全局自相关指数Moran′s I、局部Moran散点图、LISA分布图,对毛乌素沙地近30年沙化土地时空动态过程及分布情况进行研究,以期为沙化土地治理提供依据。结果表明:1)近30年,毛乌素沙地沙化土地发展以2000年为截点,2000年之前呈现发展趋势,2000年以后呈现逆转趋势。2)不同类型沙化土地Moran′s I指数均为正数,呈空间正相关,沙漠化类型分布情况具有一定的空间关联性,毛乌素沙地流动沙地主要聚集在乌审旗、鄂托克前旗、鄂托克旗;半固定沙地主要聚集在毛乌素沙地的东北部地区的神木县和榆阳区;固定沙地主要分布在神木县等边缘地区;盐碱地主要集中在神木县。在今后制定和规划沙化土地利用时,可参考沙化土地类型分布区域,从而制定相应政策与方案,提高治沙效率。

Taking remote sensing images of 1990,2000,2010 and 2016 as data sources,the temporal and spatial dynamic process and distribution of Sandy Land in Mu Us Sandy Land in recent 30 years were studied through the annual conversion of sandy land area in different periods,sandy land of different degrees and global autocorrelation index Moran′s I,local Moran scatter plot and LISA distribution map.In order to provide the basis for desertification control.The following conclusions were obtained,1) In recent 30 years,the development of sandy land in Mu Us Sandy Land had taken 2000 as the cutoff point,showing a development trend before 2000 and a reversal trend after 2000.2) Moran′s I index of different types of desertified land was positive,showing a positive spatial correlation.The distribution of desertification types had a certain spatial correlation.The mobile sands in Mu Us Sandy Land were mainly concentrated in Uxin Qi,Otog Front Banner and Etuoke Banner.Semi-fixed Sandy Land was mainly concentrated in the northeast of Mu Us sandy land in Shenmu county and Yuyang District.Fixed sandy land was mainly distributed in marginal areas such as Shenmu county.Saline-alkali land was mainly concentrated in Shenmu county.In the future,when making and planning the use of desertified land,reference can be made to the distribution areas of desertified land types so as to formulate corresponding policies and plans to improve the efficiency of desertification control.