华北北部区域土壤侵蚀及影响因素的时空变化  

Spatio-temporal variations of soil erosion and its drivers in the northern region of North China

作　　者：王慧琴[1] 孙保平[1] 余新晓[1] 信忠保[1] 贾国栋[1] WANG Huiqin;SUN Baoping;YU Xinxiao;XIN Zhongbao;JIA Guodong(Key Laboratory of State Forestry and Grassland Administration on Soil and Water Conservation, Beijing Forestry University, 100083, Beijing, China)

机构地区：[1]北京林业大学水土保持国家林业和草原局重点实验室,北京100083

出　　处：《中国水土保持科学》2021年第3期8-18,共11页Science of Soil and Water Conservation

基　　金：国家重点研发计划项目“坝上高原及华北北部山地沙化土地治理与沙产业技术研发及示范”(2016YFC0500802);科技创新服务能力建设-协同创新中心-林果业生态环境功能提升协同创新中心项目(CEFF-PXM2019_014207_000099)。

摘　　要：坝上高原与华北北部山区生态环境脆弱,水土流失严重,潜在威胁着该地区及周边地区的生态安全和可持续发展。为了了解研究区土壤侵蚀动态,为区域土地综合治理、改善水土保持建设措施提供科学依据,选取1998—2015年气象、NDVI数据集及地理相关数据,应用USLE、RWEQ模型及趋势分析法,研究该区域土壤侵蚀变化特征及其影响因素的时空分布与变化趋势。结果表明:1)研究区的土壤侵蚀分布自西北向东南,由以风力侵蚀为主过渡到以水力侵蚀为主,在1998—2015年期间水力侵蚀显著下降,虽自2008年风力侵蚀有所上升,但整体呈下降趋势;2)土壤、地形特征具有空间差异性,研究区西北部海拔高、地势平缓,东南部地势起伏、坡度坡长因子及土壤可蚀性相对较高;3)降雨侵蚀力、气象(风力)因子是土壤侵蚀产生的重要驱动因素,区域特征明显,总体上分别呈上升趋势和轻微下降趋势,随着植被覆盖度的提高,土壤流失量逐渐减少,京津风沙源区的植被修复工程起到了不可忽视的作用。[Background]The ecological environment of Bashang Plateau and northern mountainous region in North China is fragile and soil erosion is serious,which potentially threatens the ecological security and sustainable development of this region and surrounding areas.The purpose of this study is to improve the understanding of soil erosion dynamic in the study area,and to provide scientific basis for comprehensive land management and improvement of soil and water conservation measures in the region.[Methods]We selected meteorological data,NDVI data sets and geo-related data from 1998 to 2015,and applied the USLE,RWEQ model and trend analysis to study the soil erosion dynamics in the region and its influencing factors of spatiotemporal distribution and change trends.[Results]1)The distribution of soil erosion in the study area changed from wind erosion to water erosion from northwest to southeast.During 1998-2015,water erosion decreased significantly.Although wind erosion increased somewhat since 2008,the overall trend decreased and only a small part of the study area was intensified.2)Soil and topography reflected the spatial differences for soil erosion.The northwest part in the study area is flat with high elevation,while southeast part is undulating with multi-gradient slope factor and its main soil types with relatively high soil erodibility.3)Rainfall erosivity and wind force were the important driving factors for soil erosion,with strong spatiotemporal differences.Rainfall erosivity generally increased from 1998 to 2015,while overall trend of weather factor showed a slight downward trend.During the period from 1998 to 2015,fraction vegetation cover increased significantly.[Conclusions]With the increase of fraction vegetation cover,the overall soil erosion gradually decreases,and the vegetation restoration project in the sandstorm source area of Beijing and Tianjin plays an important role.

关 键 词：土壤侵蚀 地形 土壤可蚀性 降雨侵蚀力 气象因子 植被覆盖度 

分 类 号：S157.1[农业科学—土壤学]