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Assessment of Runoff and Sediment Yields Using the AnnAGNPS Model in a Three-Gorge Watershed of China  [PDF]
Lizhong Hua,Xiubin He,Yongping Yuan,Hongwei Nan
International Journal of Environmental Research and Public Health , 2012, DOI: 10.3390/ijerph9051887
Abstract: Soil erosion has been recognized as one of the major threats to our environment and water quality worldwide, especially in China. To mitigate nonpoint source water quality problems caused by soil erosion, best management practices (BMPs) and/or conservation programs have been adopted. Watershed models, such as the Annualized Agricultural Non-Point Source Pollutant Loading model (AnnAGNPS), have been developed to aid in the evaluation of watershed response to watershed management practices. The model has been applied worldwide and proven to be a very effective tool in identifying the critical areas which had serious erosion, and in aiding in decision-making processes for adopting BMPs and/or conservation programs so that cost/benefit can be maximized and non-point source pollution control can be achieved in the most efficient way. The main goal of this study was to assess the characteristics of soil erosion, sediment and sediment delivery of a watershed so that effective conservation measures can be implemented. To achieve the overall objective of this study, all necessary data for the 4,184 km 2 Daning River watershed in the Three-Gorge region of the Yangtze River of China were assembled. The model was calibrated using observed monthly runoff from 1998 to 1999 (Nash-Sutcliffe coefficient of efficiency of 0.94 and R 2 of 0.94) and validated using the observed monthly runoff from 2003 to 2005 (Nash-Sutcliffe coefficient of efficiency of 0.93 and R 2 of 0.93). Additionally, the model was validated using annual average sediment of 2000–2002 (relative error of ?0.34) and 2003–2004 (relative error of 0.18) at Wuxi station. Post validation simulation showed that approximately 48% of the watershed was under the soil loss tolerance released by the Ministry of Water Resources of China (500 t·km ?2·y ?1). However, 8% of the watershed had soil erosion of exceeding 5,000 t·km ?2·y ?1. Sloping areas and low coverage areas are the main source of soil loss in the watershed.
Application of GeoWEPP for Determining Sediment Yield and Runoff in the Orcan Creek Watershed in Kahramanmaras, Turkey  [PDF]
Alaaddin Yüksel,Abdullah E. Akay,Recep Gundogan,Mahmut Reis,Muzaffer Cetiner
Sensors , 2008, DOI: 10.3390/s8021222
Abstract: The geo-spatial interface of the WEPP model called GeoWEPP uses digital geo-referenced information integrated with the most common GIS tools to predict sedimentyield and runoff. The model determines where and when the sediment yield and runoffoccurs and locates possible deposition places. In this study, the sediment yield and runofffrom Orcan Creek watershed in Kahramanmaras region was estimated by using GeoWEPPmodel. To investigate the performance of the model, the sediment yield and runoff resultsfrom the GeoWEPP model were compared with the observed monthly data collected fromthe sample watershed. The average Root Mean Square Errors (RMSE) between observedand predicted average annual sediment yield and runoff were 2.96 and 8.43, respectively.The index of agreement was 0.98 and 0.99 for sediment yield and runoff, respectively,which indicated that the model predictions provided good results.
Application of GeoWEPP for Determining Sediment Yield and Runoff in the Orcan Creek Watershed in Kahramanmaras, Turkey
Alaaddin Y????ksel,Abdullah E. Akay,Recep Gundogan,Mahmut Reis
Sensors , 2008,
Abstract: The geo-spatial interface of the WEPP model called GeoWEPP uses digital geo-referenced information integrated with the most common GIS tools to predict sedimentyield and runoff. The model determines where and when the sediment yield and runoffoccurs and locates possible deposition places. In this study, the sediment yield and runofffrom Orcan Creek watershed in Kahramanmaras region was estimated by using GeoWEPPmodel. To investigate the performance of the model, the sediment yield and runoff resultsfrom the GeoWEPP model were compared with the observed monthly data collected fromthe sample watershed. The average Root Mean Square Errors (RMSE) between observedand predicted average annual sediment yield and runoff were 2.96 and 8.43, respectively.The index of agreement was 0.98 and 0.99 for sediment yield and runoff, respectively,which indicated that the model predictions provided good results.
Impact of DEM mesh size on AnnAGNPS runoff and sediment predictions for a small-scale hilly watershed
DEM格网尺度对AnnAGNPS预测山地小流域径流和物质输出的影响

TIAN Yaowu,HUANG Zhilin,ZENG Lixiong,XIAO Wenfa,MA Deju,
田耀武
,黄志霖,曾立雄,肖文发,马德举

环境科学学报 , 2009,
Abstract: The input of nutrients from agricultural non-point sources(AGNPSs),sediment delivery and worsening of water quality have become challenging issues threatening water security,human health and natural ecosystems in the Three Gorges Reservoir area.The agricultural non-point source(AGNPS)model is a useful tool for analysis of agricultural watershed management scenarios.The accuracy of agricultural nonpoint source pollution models depends to a great extent on how well model input spatial parameters describe the ...
Impact of parameter spatial aggregation on AnnAGNPS predictions for Heigou watershed in Three Gorges Reservoir Area conditions
三峡库区黑沟流域AnnAGNPS参数空间聚合效应

黄志霖,田耀武,肖文发,曾立雄,马德举
生态学报 , 2009,
Abstract: Agriculture has been identified as a leading source of Nonpoint Source (NPS) pollution as a result of its intensive fertilizer applications and crop management practices, and has led to ecological and human health concerns in the Three Gorges Reservoir Area (TGRA), China. Watershed models, Annualized Agricultural Nonpoint Source (AnnAGNPS), are considered a cost-effective and time-efficient approach for the assessment of pollutant loads and management practices, are coupled with GIS to facilitate watershed planning and management, which offer an unprecedented flexibility in the organization of spatial data, the spatial extent of input parameter aggregation has previously been shown to have a substantial impact on model output. However, the aggregation of spatial information in the GIS, the effects of data aggregation on model input parameters, such as land use and cover and soil type, are not well studied in watershed of TGRA condition. For the study watershed, values of critical source area (CSA) and minimum source channel length (MSCL) was set from 0.5 to 15 hm2 and the MSCL from 7.5 to 200 m. The study focused on the impact of the size or the number of cells and spatial discretization unit (SDU) used to partition a watershed (10 watershed delineations) on the input parameter spatial aggregation and output of model, the results show that across levels of watershed partitioning, there are different extent of parameter spatial aggregation of land use and soil types. The results indicate that input parameter spatial aggregation had little effect on runoff yields predictions, and more effect on sediment, total nitrogen and phosphorous loads; within the range of acceptable accuracy, in this paper, the applicability and predictive capacity of AnnAGNPS model in TGRA conditions is examined. The optimal threshold values of SDU, relative to the scale of Heigou watershed and TGRA conditions, required to adequately predicting runoff, sediment yields and nitrogen, phosphorous were found to be around 0.5-18, 2-6, 0.5-6 hm2, respectively. The model can be applied for estimation of runoff and sediment losses with acceptable accuracy in TGRA, the CSA and MSCL values determine the hydrographic segmentation of the watershed and the cell size, especially in heterogeneous areas of the watershed, which can increase the accuracy of model results, which indicates that greater attention should be made to partition a watershed to match the underlying assumptions of sub-models within AnnAGNPS.
Nonpoint Source Pollution Model, AnnAGNPS, Assessment for a Mixed Forested Watershed in Three Gorges Reservoir Area
非点源污染模型AnnAGNPS在三峡库区林农复合小流域模拟效果评定

HUANG Zhi-lin,TIAN Yao-wu,XIAO Wen-f,ZENG Li-xiong,MA De-ju,
黄志霖
,田耀武,肖文发,曾立雄,马德举

环境科学 , 2009,
Abstract: Watershed models provide a cost-effective and efficient means of estimating the pollutant loadings entering surface waters,especially when combined with traditional water quality sampling and analyses.But there have often been questions about the accuracy or certainty of models and their predictions.The main goal of this study was to evaluate the performance of AnnAGNPS(Annualized AGricultural NonPoint Source)Pollution Model,in simulating runoff,sediment loading and nutrient loadings under Three Gorges Rese...
Modelling Pollutant Loads and Management Alternatives in Jiulong River Watershed with AnnAGNPS
AnnAGNPS模型在九龙江流域农业非点源污染模拟应用

HONG Hua-sheng,HUANG Jin-liang,ZHANG Luo-ping,DU Peng-fei,
洪华生
,黄金良,张珞平,杜鹏飞

环境科学 , 2005,
Abstract: The modelling package Annualized Agricultural Nonpoint Source Model (AnnAGNPS) was used to predict pollutant loads, and simulate catchment processes and management practices in Jiulong River watershed, a medium-sized mountainous watershed in southeast of China. Four typical sub-watersheds were primarily chosen to calibrate AnnAGNPS model by data collected from storm events during the period of April to September, 2003. The model was further validated in the two biggest branches of Jiulong River watershed, i.e. West river and North river by the data regarding climate, and land using condition in 2002 - 2003. The simulation results show that annual total nitrogen load was 24.76kg/(hm2 x a) and 10.28kg/(hm2 x a) in the West river and North river, respectively, and annual total phosphorus load was 0.67 kg/(hm2 x a) and 0.40 kg/(hm2 x a) in the West river and North river, respectively. With the support of AnnAGNPS model, several management alternatives were separately simulated in the typical sub-watersheds, West river and North river. In the specific cell with cell-ID of 92 in Tianbao and Xiandu sub-watershed, after reforesting in sloping field, runoff surface, sediment yield, total nitrogen load and total phosphorus load cut down with 21.6%, 25.9%, 96% and 79.2%, respectively. In West river, with the cultivation plant changing from banana into rice, the total nitrogen, dissolved nitrogen, total phosphorus and dissolved phosphorus cut down with 23.83%, 25.44%, 9.08% and 19.84%, respectively. In North river, when removing all the hoggerys, nitrogen and dissolved nitrogen cut down with 63.54% and 76.92% , respectively.
The effect of watershed scale on HEC-HMS calibrated parameters: a case study in the Clear Creek watershed in Iowa, USA
H. L. Zhang,Y. J. Wang,Y. Q. Wang,D. X. Li
Hydrology and Earth System Sciences Discussions , 2013, DOI: 10.5194/hessd-10-965-2013
Abstract: In this paper, we use the Hydrologic Modeling System (HEC-HMS) to simulate two flood events to investigate the effect of watershed subdivision in terms of performance, the calibrated parameter values, the description of hydrologic processes, and the subsequent interpretation of water balance components. We use Stage-IV hourly NEXRAD precipitation as the meteorological input for ten model configurations with variable sub-basin sizes. Model parameters are automatically optimized to fit the observed data. The strategy is implemented in Clear Creek Watershed (CCW), which is located in the upper Mississippi River basin. Results show that most of the calibrated parameter values are sensitive to the basin partition scheme and that the relative relevance of physical processes, described by the model, change depending on watershed subdivision. In particular, our results show that parameters derived from different model implementations attribute losses in the system to completely different physical phenomena without a notable effect on the model's performance. Our work adds to the body of evidence demonstrating that automatically calibrated parameters in hydrological models can lead to an incorrect prescription of the internal dynamics of runoff production and transport. Furthermore, it demonstrates that model implementation adds a new dimension to the problem of non-uniqueness in hydrological models.
Developing participatory models of watershed management in the Sugar Creek watershed (Ohio, USA)
Jason Shaw Parker,Richard Moore,Mark Weaver
Water Alternatives , 2009,
Abstract: The US Environmental Protection Agency (USEPA) has historically used an expert-driven approach to water and watershed management. In an effort to create regulatory limits for pollution-loading to streams in the USA, the USEPA is establishing limits to the daily loading of nutrients specific to each watershed, which will affect many communities in America. As a part of this process, the Ohio Environmental Protection Agency ranked the Sugar Creek Watershed as the second "most-impaired" watershed in the State of Ohio. This article addresses an alternative approach to watershed management and that emphasises a partnership of farmers and researchers, using community participation in the Sugar Creek to establish a time-frame with goals for water quality remediation. Of interest are the collaborative efforts of a team of farmers, researchers, and agents from multiple levels of government who established this participatory, rather than expert-driven, programme. This new approach created an innovative and adaptive model of non-point source pollution remediation, incorporating strategies to address farmer needs and household decision making, while accounting for local and regional farm structures. In addition, this model has been adapted for point source pollution remediation that creates collaboration among local farmers and a discharge-permitted business that involves nutrient trading.
Testing AnnAGNPS for water quality modelling in the typical sub-watersheds in Jiulong River watershed
AnnAGNPS模型在九龙江典型小流域的适用性检验

HUANG Jinliang,HONG Huasheng,DU Pengfei,ZHANG Luoping,
黄金良
,洪华生,杜鹏飞,张珞平

环境科学学报 , 2005,
Abstract: An interface, in which ArcView Geographic Information System(GIS) was integrated with Annualized Agricultural Non-Point Source Model (AnnAGNPS), was used as a procedure to input, analyze, and visualize spatial data that agricultural Non-point source pollution concerned. Four typical sub-watersheds in southeast of China were chosen to test AnnAGNPS model from storm evens during the period of April to September, 2003. Then, the model was run to simulate the annual runoff, sediment and nutrient yield. The simulation results show that the event flows and nitrogen exports were simulated efficiently with AnnAGNPS, but only moderate accuracy is achieved for prediction of event-based sediment yield and phosphorus exports, especially the prediction of sediment yield and total-phosphorus show obvious uncertainties.
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