中文摘要：

以鄂尔多斯高原杭锦旗北部独贵塔拉镇的过渡带为研究对象，通过样线调查，研究了水分梯度下天然植被的空间分布规律．TWINSPAN的分类结果表明，群落以中生和旱生为主，一些耐盐的植物散布其中；相邻样方间相似性指数的变化反映了不同类型群落在研究区内的镶嵌分布．从而形成了该区域内群落的多样性和复杂性．对植被样方与地形地貌因子的CCA排序结果显示，植被群落空间格局的形成更多地取决于区域内的水分变化梯度．在本文的研究尺度上，这种水分变化梯度主要由微地形地貌的变化来决定。而不是由与黄河的距离因子来决定．因此，在本区域的土地开发利用过程中，应充分考虑目前已经形成的相对稳定的地形地貌单元特点，在缺乏完善的风沙防护措施和排水除盐措施的情况下．不宜采取大规模平整土地进行综合开发．

英文摘要：

With Duguitala Township in the north part of Hangjin County as an example, this paper studied the spatial distribution pattern of natural vegetation along moisture gradient at the north edge of Ordos Plateau. The results showed that based on TWINSPAN classification, the communities were dominated by mesophytes and xerophytes, and there were some halophytes in some quadrats. The similarity indices of neighboring quadrats could reflect the mosaic pattern of different type communities, and thus, the diversity and complexity of communities along this gradient, which could be reconfirmed by DCA ordination. The CCA ordination for quadrats and geomorphological factors indicated that in this transitional region, the formation of vegetation＇s spatial distribution pattern was determined by moisture gradient, while the latter was controlled not by the distance from the main course of the Yellow River but by the change of micro geomorphulogy. In the land exploitation of this region, relatively stable geo-morphological units should be taken into consideration, and large scale land exploitation through surface leveling should be avoided if shelterbelt measures and drainage and desalinizeation system were defective. This study would be helpful to the protection of natural vegetation and the integrated development of agriculture and animal husbandry.