摘要
以地处中国黄土高原最西部的甘肃省定西市安定区为研究对象,运用GIS方法和USLE土壤侵蚀模型,分析评价该区域退耕还林(草)工程建设前后的土壤侵蚀变化状况。结果表明:8 a间该区域平均侵蚀模数由1999年的5 363.65 t/km2.a下降到2007年的2 664.32 t/km2.a;从无明显侵蚀到剧烈侵蚀,侵蚀面积随强度等级的增加而锐减,其中无明显侵蚀保留率最大,剧烈侵蚀转出率最大。可见,实施退耕还林(草)工程后区域土壤侵蚀得到有效控制,退耕还林(草)对水土保持起到了明显的积极作用。
The Anding district of Dingxi city,located in the western Loess Plateau of China,was taken as the research object.Based on the technology of geographical information system（GIS） and the model of soil erosion degree（USLE）,the changes of soil erosion before and after the project of returning farmland to forest were analyzed and evaluated in this region.The results showed that the annual average soil erosion modulus deceased from 5 363.65 t/km2·a in 1999 to 2 664.32 t/km2·a in 2007;from no significant erosion to severe erosion,erosion area sharply decreased with increasing intensity level;the no significant erosion had the highest retention rate and the severe erosion had the highest inter-conversion rate.Therefore,applying project of returning farmland to forest has been effectively controlled soil erosion in this region and has played a significant positive effect in conserving soil and water.
出处
《湖南农业科学》
2011年第6期82-85,89,共5页
Hunan Agricultural Sciences
基金
国家林业局林业公益性行业科研专项经费资助项目(201004018)
