Spatial heterogeneity of plant communities on desert steppe in Ningxia

The most significant feature of plants on desert steppe is the deficient species, with most of them being xerophilous. These plants are of high-degree spatial heterogeneity and close to the natural environments. Differences in small terrains will inevitably lead to changes in the species diversity of plant communities and the spatial heterogeneity on different scales. Effects of different micro-landforms on the spatial heterogeneity of plant communities on desert steppe were studied in September, 2011 in the desert steppe that had been hill-closing afforested for almost ten years in the experimental area in Yanchi County, Ningxia, with the grassland communities’ spatial differentiations in different slope places being researched in scales using line transects. The results are as the following: the spatial heterogeneity of plant communities differs in different slope aspects and different slope positions; the subshrubs function group is of most obvious patchiness in the spatial distribution, perennials function group following behind; annuals function group shows a higher degree of patchiness in shady slopes but much lower in sunny slopes; as for the succession of the grassland plants function groups, the perennials function group has developed to a relatively stable state, the subshrubs function group is in the growing period, and the annuals function group grows better in the shady slopes than in the sunny slopes.