Search Results - "Harmel, R."

Assessment and Synthesis of 50 Years of Published Drainage Phosphorus Losses by Christianson, L. E., Harmel, R. D., Smith, D., Williams, M. R., King, K.

“…The prevalence of anthropogenic drainage systems in intensively cropped areas across North America combined with the degradation of important freshwater…”
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Consideration of measurement uncertainty in the evaluation of goodness-of-fit in hydrologic and water quality modeling by Daren Harmel, R., Smith, Patricia K.

“…As hydrologic and water quality (H/WQ) models are increasingly used to guide water resource policy, management, and regulation, it is no longer appropriate to…”
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4R Water Quality Impacts: An Assessment and Synthesis of Forty Years of Drainage Nitrogen Losses by Christianson, L. E., Harmel, R. D.

“…The intersection of agricultural drainage and nutrient mobility in the environment has led to multiscale water quality concerns. This work reviewed and…”
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Using nutrient transport data to characterize and identify the presence of surface inlets in regions with subsurface drainage by Flores, Luke, Bailey, Ryan T., Harmel, R. Daren

“…Surface inlets route ponded surface water into subsurface drainage networks and are prevalent throughout North America. Despite serving as a nutrient loss…”
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SWAT Check: A Screening Tool to Assist Users in the Identification of Potential Model Application Problems by White, Michael J., Harmel, R. Daren, Arnold, Jeff G., Williams, Jimmy R.

“…The Soil and Water Assessment Tool (SWAT) is a basin‐scale hydrologic model developed by the United States Department of Agriculture Agricultural Research…”
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The Role of Field‐Scale Management on Soil and Surface Runoff C/N/P Stoichiometry by Smith, Douglas R., Jarvie, Helen P., Harmel, R. Daren, Haney, Rick L.

“…Agricultural runoff is an important contributor to water quality impairment. This study was conducted to evaluate the potential role of field‐scale management…”
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Uncertainty in monitoring E. coli concentrations in streams and stormwater runoff by Harmel, R.D., Hathaway, J.M., Wagner, K.L., Wolfe, J.E., Karthikeyan, R., Francesconi, W., McCarthy, D.T.

“…•Comprehensive analysis of uncertainty in E. coli concentrations is presented.•Sample collection often contributes highest uncertainty to E. coli…”
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Soil Quality and Metabolic Activity Assessment after Fifty-Seven Years of Agricultural Management by Stott, Diane E, Karlen, Douglas L, Cambardella, Cynthia A, Harmel, R. Daren

“…Soil quality assessment is a process for understanding long-term effects of soil and crop management. Our objective was to assess those effects on Vertisols in…”
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The MANAGE Drain Load database: Review and compilation of more than fifty years of North American drainage nutrient studies by Christianson, L.E., Harmel, R.D.

“…•1279 site-years from 91 studies were compiled in the new MANAGE drain load table.•Hydrologic and management impacts on water quality and crop yield were…”
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Effects of sampling strategies and estimation algorithms on total nitrogen load determination in a small agricultural headwater watershed by Li, Ying, Yen, Haw, Daren Harmel, R., Lei, Qiuliang, Zhou, Jiaogen, Hu, Wanli, Li, Wenchao, Lian, Huishu, Zhu, A-Xing, Zhai, Limei, Wang, Hongyuan, Qiu, Weiwen, Luo, Jiafa, Wu, Shuxia, Liu, Hongbin, Li, Xiaohong

“…•Uncertainty of sampling frequency and algorithm on load estimation was examined.•Seasonal and annual total N (TN) loads were estimated in a small agricultural…”
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Evaluating, interpreting, and communicating performance of hydrologic/water quality models considering intended use: A review and recommendations by Harmel, R.D., Smith, P.K., Migliaccio, K.W., Chaubey, I., Douglas-Mankin, K.R., Benham, B., Shukla, S., Muñoz-Carpena, R., Robson, B.J.

“…Previous publications have outlined recommended practices for hydrologic and water quality (H/WQ) modeling, but limited guidance has been published on how to…”
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Simulating synergistic effects of climate change and conservation practices on greenhouse gas emissions and crop growth in long-term maize cropping systems by Cheng, Haomiao, Yu, Qilin, Qi, Zhiming, Bukovsky, Melissa S., Xue, Lulin, Jin, Virginia L., Ma, Liwang, Daren Harmel, R., Chen, Xiaoping, Ji, Shu, Miao, Lingzhan, Feng, Shaoyuan

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A Meta‐Analysis on the Effect of Agricultural Conservation Practices on Nutrient Loss by Nummer, Stephanie A., Qian, Song. S., Harmel, R. Daren

“…Conservation practices are widely used to reduce N and P loads from agricultural fields and minimize their impact on water quality, but research using…”
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Grazing Effects on Bovine-Associated and Background Fecal Indicator Bacteria Levels in Edge-of-Field Runoff by Wagner, Kevin, Gentry, Terry, Harmel, R., Pope, Emily, Redmon, Larry

“…Excessive levels of fecal indicator bacteria are a major cause of water quality impairment. Grazing and its management may significantly impact bacteria…”
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A modified F-test for evaluating model performance by including both experimental and simulation uncertainties by Sima, Nathan Q., Harmel, R. Daren, Fang, Quan X., Ma, Liwang, Andales, Allan A.

“…Experimental and simulation uncertainties have not been included in many of the statistics used in assessing agricultural model performance. The objectives of…”
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Applying Statistical Causal Analyses to Agricultural Conservation: A Case Study Examining P Loss Impacts by Qian, Song S., Harmel, R. Daren

“…Estimating the effect of agricultural conservation practices on reducing nutrient loss using observational data can be confounded by factors such as differing…”
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Improving the spatial representation of soil properties and hydrology using topographically derived initialization processes in the SWAT model by Fuka, Daniel R., Collick, Amy S., Kleinman, Peter J.A., Auerbach, Daniel A., Harmel, R. Daren, Easton, Zachary M.

“…Topography exerts critical controls on many hydrologic, geomorphologic and biophysical processes. However, many watershed modelling systems use topographic…”
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Improved Simulation of Edaphic and Manure Phosphorus Loss in SWAT by Collick, Amy S., Veith, Tamie L., Fuka, Daniel R., Kleinman, Peter J.A., Buda, Anthony R., Weld, Jennifer L., Bryant, Ray B., Vadas, Peter A., White, Mike J., Harmel, R. Daren, Easton, Zachary M.

“…Watershed models such as the Soil Water Assessment Tool (SWAT) and the Agricultural Policy Environmental EXtender (APEX) are widely used to assess the fate and…”
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Shrink–swell behavior of soil across a Vertisol catena by Dinka, Takele M., Morgan, Cristine L.S., McInnes, Kevin J., Kishné, Andrea Sz, Daren Harmel, R.

“…► Soil subsidence across outwardly uniform soils varied spatially and temporally. ► The coefficient of linear extensibility estimated soil subsidence from…”
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Phosphorus Dynamics in Long-Term Flooded, Drained, and Reflooded Soils by Tian, Juan, Dong, Guiming, Karthikeyan, Raghupathy, Li, Lin, Harmel, R.

“…In flooded areas, soils are often exposed to standing water and subsequent drainage, thus over fertilization can release excess phosphorus (P) into surface…”
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