[目的]盐碱荒地是由于土壤盐渍化和次生盐渍化而形成的未开发利用的土地,掌握其空间分异特征并探究其成因,对于开发盐碱荒地的潜力和增加土地后备资源有着重要意义。[方法]该研究对大同盆地的3.44万hm2盐碱荒地进行了土壤采样调查,布设调查样点1 729个,采用空间分析方法 ,利用DEM、土地类型图等计算地形位分布指数、全盐量反距离权重插值、河流纵比降等,从地形、地质、水文、土壤几个方面分析大同盆地盐碱荒地的成因。[结果]1研究区盐碱荒地的地形位分布指数与其它土地利用类型差异明显,主要分布在地形低洼、地势起伏度小的区域。2由于大同盆地形成向中心倾斜的平原,并在洪积扇前形成凹地,导致积水不易排出。3河流纵向上全盐量的分布呈现出中游最高,面积最大,上游次之,下游最低;河流横向上全盐量分布总体为越靠近河流,全盐量越高,距离河流越远,全盐量越低。4大同盆地盐碱荒地土壤以潮土和盐土为主,这两种土壤类型均为重度盐化和碱化。[结论]从盐碱荒地的分布得出大同盆地有两大积盐中心,分别位于桑干河流域的山阴、应县一带,以及洋河流域的阳高、天镇一带。从其成因和分布提出治理盐碱荒地的关键是降低地下水位,有针对性的进行盐碱荒地改良的水利规划,为大同盆地盐碱荒地的治理提供理论依据。 [Objective] The saline-alkali wasteland is an undeveloped and utilized land formed by soil salinization and secondary salinization. It is necessary to grasp its spatial differentiation characteristics and explore its causes, which has great potential for developing saline-alkali wasteland and increasing land reserve resources Has important meaning. [Method] The soil sampling survey was conducted on 34,400 hm2 saline-alkali wasteland in Datong Basin. A total of 1 729 sampling sites were surveyed. Spatial analysis method, DEM and land type maps were used to calculate the topographic distribution index, Inverse distance weight interpolation and river vertical ratio decrease. The causes of saline-alkali wasteland in Datong Basin are analyzed from topography, geology, hydrology and soil. [Result] 1 The distribution index of landform of saline-alkali wasteland in study area is obviously different from other land use types, mainly distributed in the areas with low relief and low relief. 2 As the Datong Basin formed a plain tilted to the center and formed a concave land before the alluvial fan, water could not be easily discharged. The distribution of total salinity in the vertical direction of the river shows the highest in the middle reaches, the largest in area, the highest in the upper reaches and the lowest in the lower reaches. The total salinity distribution in the river is generally closer to the river, the higher the total salinity, the farther away from the river, The lower the amount. Soil in the saline-alkali-wasteland in the Datong Basin is dominated by alluvial soil and saline soil, both of which are heavily salinized and alkalized. [Conclusion] From the distribution of saline-alkali wasteland, there are two large salt accumulation centers in Datong Basin, which are located in the areas of Shanyin and Yingxian in the Sanggan River basin, and in the areas of Yanggao and Tianzhen in Yanghe River Basin. According to its causes and distribution, the key to the treatment of saline-alkali wasteland is to reduce the water table and to make targeted water conservancy planning for the improvement of saline-alkali wasteland, so as to provide a theoretical basis for the treatment of saline-alkali wasteland in the Datong Basin.