摘要
以黄土高原典型退耕区宁夏泾源县为研究对象,基于2000及2016年的土地利用和NDVI数据,运用地理信息系统方法,分析当地土地利用及林草植被覆盖的时空变化特征,在此基础上评估县域土壤侵蚀变化情况.研究结果表明:①2000~2016年泾源县耕地、草地面积减少,林地面积增加并成为区域优势土地利用类型,同时"草地-林地""耕地-林地"是最主要的土地利用变化类型,且其变化主要发生在8°~15°及15°~25°区域.②研究期内,泾源县林草植被覆盖度增加,植被覆盖度>75%的林草地面积增加了77%,且植被覆盖度变化最大的区域为15°~25°区域.③退耕还林工程实施后,泾源县土壤侵蚀面积减少了47%,年均土壤侵蚀量减少119.64×10~4t,其中61%源于林草地土壤侵蚀量的减少.
To evaluate soil erosion changes driven by the Grain for Green Program in the Loess Plateau,the study analyzes the spatiotemporal changes in the land use and vegetation coverage in Jingyuan County from 2000 to 2016 based on land use and normalized difference vegetation index(NDVI)data.The findings reveal the following.(1)The farmland and grassland areas decreased,while forestland area increased and became the dominant land-use type in Jingyuan after the program’s implementation.The conversions of grassland and farmland to forestland were the main types of land-use change,and occurred predominantly in areas with slopes of 8°~15°and 15°~25°.The proportion of farmland decreased with the increase in the slope gradient,whereas the conversion of forestland presented a contrary variation.(2)The vegetation coverage of forestland and grassland increased between 2000 and 2016;particularly,areas with vegetation coverage of more than 75%increased by 77%,and the largest changes occurred in areas with slopes of 15°~25°.(3)The soil erosion area decreased by 47%after the implementation of the program,and the amount of soil erosion decreased by 1.1964 million tons,61%of which was due to the decrease of soil erosion in forestland and grassland.
作者
皮泓漪
张萌雪
夏建新
PI Hongyi;ZHANG Mengxue;XIA Jianxin(College of Life and Environmental Sciences of Minzu University of China,Beijing 100081,China)
出处
《应用基础与工程科学学报》
EI
CSCD
北大核心
2020年第3期522-534,共13页
Journal of Basic Science and Engineering
基金
国家水体污染控制与治理重大专项(2017ZX07101002)
中央民族大学少数民族事业发展协同创新项目
关键词
土地利用
时空变化
NDVI
坡度
植被覆盖度
土壤侵蚀
退耕区
land use
spatiotemporal changes
NDVI
vegetation coverage
soil erosion
the Grain for Green Program
作者简介
皮泓漪(1985—),女,博士研究生,E-mail:pphongyi@sina.com;通信作者:夏建新(1969—),男,教授,E-mail:jxxia@vip.sina.com
