关键词: 人为侵蚀, 土石场, 空间分布, 景观生态影响度

Abstract: The vegetation and soil water environment in Minqin oasis-desert transitional zone have obvious spatial heterogeneity with the increasing distance from oasis, and can be divided into 4 sections, according to the differentiation of landscapes. This paper studied the vegetation features in each of the sections, and the soil water features in the inter-dunes and shrub islands in the sections. In the transitional zone, the total coverage was about 36%, shrub coverage was 18.7%, and herbal coverage was 18.0%. The species richness was 19. From section 1 to section 4, the species composition, vegetation coverage, dominant species, and constructive species all exhibited the features corresponding to the stand conditions of each section, with a pattern of large shrub→ herb → shrub→ herb. Accordingly, the geomorphology showed the pattern of fixed →semi-shifting → semi-fixed → shifting. There were obvious differences in the vertical distribution of soil water content among the sections, and 5-60 cm soil layer was the main rainwater retention layer. Due to the occurrence of aquiclude, the soil water content appeared a second fluctuation in 60-180 cm soil layer from section 1 to section 3. The water accumulation above the aquiclude was an important supplementary to the aboveground vegetation. The soil water content in the dunes from section 1 to section 3 decreased obviously.

Key words: Artificial erosion, Quarry, Spatial distribution, Landscape ecological impact degree