基于SWAT模型的流域土地利用格局变化对面源污染的影响  

Effect of land use/landscape changes on diffuse pollution load from watershed based on SWAT model

作　　者：耿润哲[1,2] 李明涛[1,3] 王晓燕[1] 庞树江 

机构地区：[1]首都师范大学资源环境与旅游学院,北京100048 [2]环境保护部环境与经济政策研究中心,北京100029 [3]兰州城市学院城市经济与旅游文化学院,兰州730070

出　　处：《农业工程学报》2015年第16期241-250,共10页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(41271495);高等学校博士学科点专项科研基金联合资助项目(20121108110006)

摘　　要：近年来随着流域经济社会的快速发展,密云水库流域的土地利用格局也发生了明显的改变,作为影响流域非点源污染输出的主要因素,探讨土地利用格局的演变对非点源污染的影响对有效控制非点源污染具有重要的意义。该文以密云水库上游流域为研究区,从土地利用变化与污染过程相互作用的角度出发,开展流域非点源污染过程对土地利用变化的响应研究。基于流域1995年、2000年、2005年3期的土地利用数据,基于SWAT(soil and water assessment tool)模型,模拟评价流域非点源污染负荷分布特征,并应用景观格局指数、典范对应分析(canonical correspondence analysis,CCA)和通径分析等方法,从全流域和三级保护区等多空间尺度,量化分析流域土地利用及其格局时空变化对非点源污染负荷的影响。研究结果表明流域的非点源负荷与土地利用格局间存在着密切的联系。格局指数能累积解释流域非点源污染负荷变化的56.3%。污染负荷受土地利用格局的破碎度和形状的影响较大。通径分析的结果表明,耕地、林地面积比例、形状指数和斑块密度是影响研究区非点源污染负荷输出的主要因子,其中形状指数和耕地面积比例对TN、TP负荷的解释能力要明显高于其他指标。从空间尺度上看,各格局因子与非点源污染负荷的关系具有尺度效应,随着空间尺度的递增,格局对负荷的解释程度降低,在较小的尺度范围内,尤其是一级保护区的解释能力最高,达到62.9%,表明离水库越近的区域应是非点源防治高度重视的区域。The loss of nitrogen and phosphorus via non-point source （NPS） pollution in the Chaobai river watershed has become the main pollution sources of river waters in the Miyun reservoir area in the past decades. Climatic conditions and human activities directly affect changes of runoff. In addition, land use types are closely related to NPS pollution. Climate change and human activities can potentially lead to changes in runoff and can significantly impact the regional hydrology and future availability of water resources. Researches showed that NPS pollution has become an important source affecting the quality of the Miyun reservoir water environment. Therefore, exploring the impact of land use change on NPS pollution under different climate scenarios has important practical implications for control non-point source pollution in this area. In this study, Miyun reservoir watershed was used as a study area to determine the response of non-point source pollution to land use change under different climate scenarios. An integrated model system was developed which included three parts, the Soil and Water Assessment Tool （SWAT） as the hydrological and non-point source pollution estimator; the Canonical Correspondence Analysis （CCA）, and Path Analysis to explore the relationship between land use change and non-point source pollution loads. The statistical downscaling model was conducted to generate the different climate scenarios for discussing the impact on hydrological process and non-point source pollution losses. The results showed that SWAT model was suitable for the ＂study area. Total nitrogen （TN） and total phosphorus （TP） loads decreased with the rainfall during 1995 to 2005, indicating that the rainfall was an important factor on the temporal variability of pollution loads. The spatial distribution of TN and TP loads were significantly affected by the comprehensive influence of rainfall and land use. The high-risk areas were mainly located in Chicheng, Chongli, and Fengning county. There was a s

关 键 词：土地利用 污染 磷 氮 SWAT模型 面源污染 密云水库 

分 类 号：X524[环境科学与工程—环境工程] F301.24[经济管理—产业经济]