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影响水环境污染的因素很多,随着人们对环保意识的增强,点源污染虽然得到了一定的管理和控制,但面源污染仍然是引起水环境污染主要影响因素。文章运用物理模拟和排污系数计算建立SWAT模型,并进行模型适用性评价及分析,结果表明,R~2、E_(NS)系数均在0.6和0.8以上,SWAT模型可适用于研究大凌河面源污染模型。通过对验证后的SWAT模型模拟不同污染源占流域面源污染的权重比例计算研究,可以得出,农村面源污染、人类生产和生活所产生的TN和TP污染、农业化肥是目前大凌河流域内入湖污染的主要污染源。 相似文献
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SWAT模型已有针对北美地区流域建立的数据库,将模型应用于我国流域时,需要另行构建数据库,主要包括土壤数据库和天气发生器。以清江流域作为研究对象,分别采用SPAW程序和土壤渗透率经验公式估算土壤水分参数及土壤下渗率,对研究区土壤按美国标准采用水文分组等方法建立土壤数据库;利用PcpSTAT、Dew02等程序估算部分难获得的气象因子,构建天气发生器。依据前述数据库建立的SWAT模型对清江流域径流分别进行月模拟和日模拟,结果表明,构建的SWAT模型在清江流域的应用取得了良好效果,模拟精度较高,对该地区水资源管理具有一定的参考和借鉴价值。 相似文献
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以郑州市贾鲁河流域为研究区,在地理信息系统技术支持下,使用DEM、土地利用、土壤、气象、人工取用水数据、农业管理措施等资料构建了基于分布式水文模型SWAT的流域水循环模拟模型,应用改进的SWAT模型进行了流域水循环模拟,并利用实测数据对模型进行了参数率定和模型验证,采用相对误差、NASH效率系数、相关系数作为模型适应性评价指标,结果表明模型在研究区有较好的适应性。可以为流域水循环演变规律的系统揭示和区域水资源的综合调控提供了技术支撑。 相似文献
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为满足北江飞来峡流域非点源污染负荷核算需要,利用SWAT模型对研究区1969-2011年日径流过程进行模拟。基于飞来峡流域水文、气象、地形、土地利用和土壤类型等资料构建SWAT径流模型,并运用SWAT-CUP中的SUFI-2方法对模型中的14个径流参数进行敏感性分析及参数率定,再进行径流模拟效果定量评价。结果表明:对径流过程有显著影响的参数主要为SCS径流曲线系数、主河道曼宁系数、地下水滞后系数以及地表径流滞后时间等;日径流率定期和验证期的效率系数均为0.83,相对误差分别为1.40%和0.58%,且大部分模拟数据落在不确定性区间内,模拟结果的不确定性较小,表明所构建的SWAT径流模型具有较高的精度,在北江飞来峡流域适用性良好。 相似文献
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Abstract In light of the current ability to treat point source pollution, nonpoint source (NPS) pollution has become the primary cause of water pollution. In order to manage and control NPS pollution, we must conduct research on NPS pollution. An effective means for such an endeavor is to construct a mathematical model. However, in the present continuous time and distributed parameter NPS models, such as SWAT, parameter requirements are so numerous that their application is very difficult. In order to make such a model convenient for application, research was first conducted before constructing a new continuous time and distributed parameter NPS pollution model based on hydrodynamics. In this paper, as one of its sub-models, the runoff sub-model is introduced. This sub-model is composed of the SCS model and the water routing model that was constructed by the authors of this paper. This water routing model is based on Saint-Venant equations. Through Laplace transform and inverse Laplace transform mathematical modeling, the outflow hydrograph that is an S-curve was obtained. Then, the authors built the relation between S-curve and water- collecting area coefficient, from which the water routing model is derived. In order to calibrate and validate the new model, the authors applied it in the Guishuihe watershed with satisfactory results. The results show that it has value in application, especially in the area where data are scarce. 相似文献
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Yan Wang Hubert J. Montas Kaye L. Brubaker Paul T. Leisnham Adel Shirmohammadi Victoria Chanse Amanda K. Rockler 《Water Resources Management》2017,31(5):1649-1664
Best Management Practices (BMPs) have become the most effective way to mitigate non-point source pollution (NPS) issues. Much attention has been paid to NPS in rural areas, where agricultural activities increase nutrients, toxics, and sediments in surface water. Stormwater from urban areas is also a major contributor to NPS pollution. For watersheds bearing various soil types and land uses, a single type of BMP cannot be the panacea to all stormwater problems. To solve these problems, a Diagnostic Decision Support System (DDSS) was developed in this research. The DDSS can identify and locate the most critical NPS areas (hotspots) within a watershed in high spatial resolution. The DDSS can provide a series of spatially distributed small-scale BMPs which are effective in treating the NPS and are suitable for the physical environment. The BMPs, varying in types and locations, are recommended at HRU (Hydrologic Response Unit) level. The DDSS was tested in Watts Branch, a small urban watershed of the Anacostia River in metropolitan Washington D.C., USA. The process-based hydrologic model, Soil and Water Assessment Tool (SWAT), was used to simulate watershed responses. The simulation results were then used by the DDSS for BMP recommendation. Hotspots of different NPS were successfully located and prescribed with spatially distributed BMPs. The DDSS serves as a useful tool to better understand urban watersheds and to make proper stormwater management plans. 相似文献
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应用区域营养盐管理模型ReNuMa,以长春市饮马河石头口门水库流域为研究对象开展研究,通过对流域总氮非点源污染的调查和模拟,定量计算和分析了总氮非点源污染时空分布规律.结果表明:该模型在研究区域适用性较好(月径流校准期R2=0.7884,Ens=0.7816;验证期R2=0.7602,Ens=0.7092;月负荷校准期R2=0.7429,Ens=0.7008;验证期R2=0.7066,Ens=0.6618).时间尺度上,雨季期总氮非点源污染负荷占总量的69%.空间尺度上,饮马河上游流域对非点源污染负荷比例最大,不同土地利用类型的总氮非点源污染负荷不同,耕地贡献比例最大,其次是农村居民点. 相似文献
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Chia-Ling Chang Tsung-Hung Hsu Yunn-Jiin Wang Jen-Yang Lin Shaw L. Yu 《Water Resources Management》2010,24(10):2339-2352
The Feitsui reservoir is a major water supply source for more than five million people in Northern Taiwan. The reservoir water quality has been good, but is threatened by eutrophication due to excessive nutrient input and siltation due to sediment loads. Recently, the water authorities in Taiwan have made considerable efforts to devise strategies using watershed conservation practices for the protection of Feitsui reservoir water quality. The control of non-point source pollution (NPS) represents one of the major strategies and the use of best management practices (BMPs) is under careful consideration. The objective of this study was to assess the effectiveness and cost of a full Feitsui watershed implementation of riparian buffer strips and other appropriate conservation practices. Based on the use of watershed simulation models and a statistical relationship between pollution reduction rate and the width and slope of a buffer strip, a methodology for the planning and design of riparian buffer strips was addressed. Data from field experiments were used to calibrate the coefficients of the regression equations. Several planning scenarios were evaluated by means of cost-benefit analysis coupled with net present value method. Data on local construction and maintenance costs for the selected design and location of buffer strips were used in the analysis. Based on several cost-benefit analyses, the scenario for installing buffer strips with 30 m width and 5% slope along both sides of tributary streams in the sub-watersheds with high nutrient (phosphorus) loadings was found to be most cost effective. 相似文献
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Access to water and water availability remains a key factor in ensuring the sustainability of development in Southern Africa. The need for guidelines to improve management of this valuable resource, and to regulate pollutant discharge, is therefore of national interest. A new and growing threat to our natural water resources is non-point source (NPS) pollution. The important distinction between point pollution and NPS pollution is that the latter is difficult to identify and the entry point of contamination to resources is diffuse and not limited to a single location. NPS pollution associated with power generation includes, but is not limited to, atmospheric deposition resulting from emissions (air and water), leachate from coal storage piles and runoff from impervious areas which are covered with dust fallout from coal and ash handling operations. Emissions of primary concern are sulfur, nitrogen and mercury. 相似文献