摘要
在GIS技术的支持下,利用137Cs含量的分异规律对土壤侵蚀的发生、分布进行了研究,并对不同土地利用背景下土壤侵蚀的空间分布规律进行了定量研究。通过137Cs强度的空间差异,分析了土壤侵蚀的强度及区域差异,及其与区域土地利用、土地覆盖变化的相互关系。结果表明:(1)黑河中游山前平原区属中度侵蚀,其土壤侵蚀强度依次为荒地>耕地>草地,草地开垦为耕地将加剧土壤侵蚀;(2)研究区内每年耕作土地的土壤侵蚀量达0 2亿t,草地的土壤侵蚀量达0.4亿t,荒地的土壤侵蚀量达1 2亿t,区内每年由这3类主要土地利用类型造成的土壤侵蚀量约为1.8亿t;(3)近20年来黑河中游山前平原区土壤侵蚀量总体呈现增加的趋势,其西部为强风蚀地区,荒漠化日益严重,南部沿山洪积扇区土地资源的大规模开发利用,在造成本区域土地恶化的同时,加剧了中部及中北部地区向荒地演化的趋势。
Under the support of the GIS technique, the occurrence and distribution of soil erosion were studied in the plain before the mountain of the Heihe river, using the ^(137)Cs technique. And the spatial distributing rules of soil erosion under the different land use background were investigated quantificational. By the spatial analysis of the ^(137)Cs intensity, that the intensity and district difference of the soil erosion can be revealed. Furthermore, the correlation between the soil erosion and the LUCC of the region was to be discussed. Results show that it was belong to secondary erosion that in the plain before the mountain in the middle part of Heihe river, and the average soil erosion rates in the past 38 years of grassland, cultivated land and waste-land were increased in turn. Moreover, grassland cultivated in large acreage will accelerate the soil erosion. Secondly, the soil erosion capacity of the grassland, cultivated land and waste-land were about 0.4 hundred million tons,0.2 hundred million tons,1.2 hundred million tons respectively. Thirdly, the soil erosion of the region was presented increased trend in recently twenty years, the west area of it was eroded more strong, that the cosmically exploitation of the soil in the south, were made the land of current region deteriorated, therefore, the evolutive trend to the waste were accelerated in the lower reaches of the river.
出处
《水土保持学报》
CSCD
北大核心
2005年第3期88-92,共5页
Journal of Soil and Water Conservation
基金
国家基金项目(40171002)
中国科学院知识创新重大项目(KZCX1-09-04)资助
