Non-Point-Source Nitrogen and Phosphorus Loadings from a Small Watershed in the Three Gorges Reservoir Area  

作　　者：ZHU BO WANG Zhenhua WANG Tao DONG Zhixin 

机构地区：[1]Key Laboratory of Mountain Environment Evolvement and Regulation,Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041,China [2]Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041,China

出　　处：《Journal of Mountain Science》2012年第1期10-15,共6页山地科学学报（英文）

基　　金：supported by the National Science & Technology Pillar Program(Grant No. 2011BAD31B03);the Special Project on Water Pollution Control by the National Science & Technology Pillar Program(Grant No. 2009ZX07104-002)

摘　　要：Non-point-source pollution has become a major threat to the water quality of the Three Gorges Reservoir(TGR);however,nutrient loadings from terrestrial sources are unclear due to a lack of in situ monitoring.A representative small watershed in the central part of the TGR area was selected to monitor the loss of nitrogen(N) and phosphorous(P) continuously along with the runoff from 2007 through 2009 to understand the exact sources and loadings.Results show that the non-point-source nitrogen and phosphorus comes mainly from the storm runoff from residential areas,citrus orchards and sloping croplands,which contributes up to 76% of the loadings in this watershed.Thus,a crucial measure for controlling non-point-source pollution is to intercept storm runoff from the three sources.Paddy fields provide a sink for non-point-source N and P by intercepting the runoff and sediment along with their different forms of nitrogen and phosphorus.The N and P removal efficiency by paddy fields from residential areas is within the range of 56% to 98%.Paddy fields are an important land-use option for reducing the non-point-source loading of N and P in the TGR area.

关 键 词：Non-point-source pollution Source and sink Nitrogen Phosphorus Paddy fields Three Gorges Reservoir area China 

分 类 号：X522[环境科学与工程—环境工程] P642.22[天文地球—工程地质学]