基于RS/GIS公路路域水土流失动态变化的研究——以榆靖高速公路为例  

Study on dynamic changes of soil and water loss along highway based on RS/GIS:an example of Yujing expressway

作　　者：陈爱侠[1] 李敏 苏智先[3] 朱小花[1] 刘晓茹[1] 曹杨[1] 

机构地区：[1]长安大学环境科学与工程学院,西安710064 [2]陕西省环境科学研究设计院,西安710054 [3]绵阳师范学院,绵阳621000

出　　处：《生态学报》2011年第12期3424-3431,共8页Acta Ecologica Sinica

基　　金：国际科技合作计划基金资助项目(2006kw-06)

摘　　要：基于RS数据源,利用ERDAS和ArcG IS软件技术,对榆靖高速公路两侧300 m范围水土流失动态变化开展研究。通过遥感图像数字处理方法,提取对水土流失起主导作用的植被覆盖度、土地利用类型、沟谷密度等因子;在矢量化等高线数据的基础上生成数字高程模型(DEM),提取地形坡度因子,将这4个因子在G IS中进行空间叠加分析。参照《土壤侵蚀分级标准》,生成研究区不同时段水土流失强度等级图,利用G IS属性统计功能对公路沿线各等级水土流失区面积进行统计,参照研究区不同侵蚀类型的土壤侵蚀模数,得出1996年和2006年公路沿线各流失区的水土流失量,并对公路沿线水土流失动态变化进行分析。结果表明:榆靖高速公路修建后沿线600 m范围水土流失总量减少19.26万t/a,水土流失呈减弱趋势。公路施工期导致水土流失增强的各种因素随着营运期固化路面的形成而逐渐消失,防沙固沙和生态恢复等措施有效改善了公路路域生态环境,对公路沿线水土流失防治起到了积极作用。YUJING expressway is the first highway built in the desert in China. Ecological environment is fragile and vegetation coverage is low along highway. A section with 60km long passes through mobile, semi-mobile and semi-fixed sand dunes so that the roadbed is prone to encroachment by sandstorms. To reduce such encroaehments, an ecological protection project was set up within 200-300 meters on both sides of roadbed. This project used the technology of low upright grid barrier, tall upright grid barrier and composite typed sand barriers. To understand the protection effect of the project during highway construction period, the dynamic changes of soil and water loss within 300 meters on both sides of YUJING Expressway were studied by using ArcGIS Spatial Analysis Platforms and ERDAS Spatial Modeling Platforms based on the digital topographic map with 1：250000 scale and two period remote sensing image taken from 1996 and 2006. The investigation area is 70.18 km^. The remote sensing digital image processing was employed to extract three factors such as vegetation coverage, land use types and gully density which dominate soil erosion. DEM （ Digital Elevation Model） was also used on the basis of vector quantization to extract another factor of geographic gradient. Furthermore the spatial overlay analysis of four factors was carried out to obtain the strength grade map at different periods. Finally the volumes of water and soil loss were calculated in the year of 1996 and 2006, respectively, according to the statistical areas of water and soil loss with different degree by using GIS and soil erosion modules of distinct erosion types in the research areas. The results show that there has been an obvious decrease in water and soil loss after the construction of Yu-Jing Expressway. The details are given as the following： The study area is basically plane and mostly composed of slow and slight slopes, of the landform grade 〈5°, 92.59% out of the total area. The maximum value of gully density in 1996 and 2006 is 3-5

关 键 词：RS/GIS 水土流失 高速公路 植被覆盖度 坡度 

分 类 号：S157[农业科学—土壤学]