摘要
退耕还林(草)等生态工程对区域用地结构及生态系统服务功能产生了重要影响。本研究基于RUSLE模型,并辅以遥感监测与GIS空间分析方法,对北方农牧交错带西段2000-2015年退耕状况及其引起的土壤保持功能变化分3个时段(2000-2005年、2005-2010年及2010-2015年)进行了探究。结果表明:北方农牧交错带西段地区2000-2015年耕地面积净减少1663.83 km2,以转为林地、草地、建设用地为主,其中耕地转林、草地净减少面积为1113.64 km2,草地和未利用地是新增耕地的主要来源;15年间土壤保持功能提升显著,退耕还林(草)工程的实施使土壤保持量增加了56.50×104t,2005-2010年由退耕所带来的土壤保持增加量在3段时期中最高;不同坡度等级的生态退耕引起的土壤保持增加量差别较大,总体随着坡度升高呈下降趋势,但在25°以上的陡坡耕地由退耕还林(草)带来的土壤保持效益又有所升高。研究对于评估北方农牧交错带西段地区实施退耕还林(草)等工程的生态效益具有重要意义,并能为区域生态保护与修复工程的建设规划提供科学依据。
Ecological engineering such as Grain for Green Project have significant impacts on the structure of regional land use and ecosystem service functions. Based on the RUSLE model and RS & GIS spatial analysis methods, this study assessed the impacts of returning farmland on soil conservation function in the western region of Farming-pastoral Ecotone of Northern China(FPENC) during 2000-2015. The results showed that the total area of farmland in the FPENC decreased by 1663.83 km2 from 2000 to 2015, which was mainly converted into forest land, grassland and construction land. The implementation of the Grain for Green Program was the main reason for farmland decrease, and the area of farmland converted into forest and grassland accounted for66.93% of the total area of farmland reduction. The newly added farmland was mostly converted from grassland and unused land, and mainly concentrated in the northern and central regions. Besides, the soil conservation function had improved significantly in the western region of FPENC during the past 15 years, and the amount of soil conservation increased by 56.50×104 t, which mainly resulted from returning farmland to forest and grassland between 2005 and 2010. In addition, the increase in soil conservation caused by ecological restoration had obvious difference in different slope grades, but the increased soil conservation generally showed decrease trend with the slope increase. Nevertheless, in some areas of slope greater than 25 degrees implemented Grain for Green Project have high benefits of soil conservation. The steep slope(slope greater than 25 degrees) area is mostly a contiguous area of extreme poverty, where is the key area implemented by a new round of Grain for Green Project and poverty alleviation projects. This study about the impact mechanism of returning farmland on soil conservation function in western region of FPENC will provide quantitative scientific basis for the planning and construction of regional ecological protection and restoration projects.
作者
殷小菡
孙希华
徐新良
张雪艳
陈德超
YIN Xiaohan;SUN Xihua;XU Xinliang;ZHANG Xueyan;CHEN Dechao(School of Geography and Environment,Shandong Normal University,Jinan 250358,China;State Key Laboratory of Resources and Environmental Information Systems,Institute of Geographi Sciences and Natural Resourees Research,Chinese Academy of Sciences,Beijing 100101,China;Jiangsu Provincial Key Laboratory of Environmental Science and Engineering,School of Environmental Science and Engineering,Jiangsu University of Science and Technology,Suzhou 215009,China)
出处
《地球信息科学学报》
CSCD
北大核心
2018年第12期1721-1732,共12页
Journal of Geo-information Science
基金
中国科学院A类战略性先导科技专项(XDA20010302).
关键词
北方农牧交错带西段
退耕
RUSLE
土壤保持功能
时空特征
farming-pastoral ecotone
returning farmland
RUSLE
soil conservation function
spatio temporal characteristics
