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Full-Text Articles in Engineering
A Portable Rainfall Simulator For Plot–Scale Runoff Studies, J. Byron Humphry, Tommy C. Daniel, Dwayne R. Edwards, Andrew N. Sharpley
A Portable Rainfall Simulator For Plot–Scale Runoff Studies, J. Byron Humphry, Tommy C. Daniel, Dwayne R. Edwards, Andrew N. Sharpley
Biosystems and Agricultural Engineering Faculty Publications
Rainfall simulators have a long history of successful use in both laboratory and field investigations. Many plot–scale simulators, however, have been difficult to operate and transport in the field, especially in remote locations where water or electricity is unavailable. This article describes a new rainfall simulator that is relatively easy to operate and transport to and from the field while maintaining critical intensity, distribution, and energy characteristics of natural rainfall. The simulator frame is constructed from lightweight aluminum pipe with a single 50 WSQ nozzle centered at a height of 3 m (9.8 ft). An operating nozzle pressure of 28 …
Vegetated Filter Strip Removal Of Cattle Manure Constituents In Runoff, Teng T. Lim, Dwayne R. Edwards, Stephen R. Workman, Brian T. Larson, Lloyd Dunn
Vegetated Filter Strip Removal Of Cattle Manure Constituents In Runoff, Teng T. Lim, Dwayne R. Edwards, Stephen R. Workman, Brian T. Larson, Lloyd Dunn
Biosystems and Agricultural Engineering Faculty Publications
Pasture runoff can contribute to elevated concentrations of nutrients, solids, and bacteria in downstream waters. The objective of this study was to determine the effects of vegetative filter strip (VFS) length on concentrations and transport of nitrogen, phosphorus, solids and fecal coliform in runoff from plots treated with cattle manure. Three plots with dimensions of 2.4 × 30.5 m were used. The upper 12.2 m of each plot was treated with cattle manure, while the lower 18.3 m acted as a VFS. Runoff produced by rainfall simulators was sampled at VFS lengths of 0, 6.1, 12.2, and 18.3 m and …
Effect Of Bmp Implementation On Storm Flow Quality Of Two Northwestern Arkansas Streams, Dwayne R. Edwards, Tommy C. Daniel, H. Don Scott, Phillip A. Moore Jr., John F. Murdoch, Paul F. Vendrell
Effect Of Bmp Implementation On Storm Flow Quality Of Two Northwestern Arkansas Streams, Dwayne R. Edwards, Tommy C. Daniel, H. Don Scott, Phillip A. Moore Jr., John F. Murdoch, Paul F. Vendrell
Biosystems and Agricultural Engineering Faculty Publications
The effectiveness of management practices in improving quality of runoff from agricultural land areas has been reported based primarily on results from plot- and field-scale studies. There is limited information available on watershed scales, particularly when the dominant agricultural land use is pasture. The objective of this study was to determine whether a program of Best Management Practice (BMP) implementation in the Lincoln Lake watershed of northwestern Arkansas was effective in reducing storm stream flow concentrations and mass transport of nitrate nitrogen (NO3-N), ammonia nitrogen (NH3-N), total Kjeldahl nitrogen (TKN), ortho-phosphorus (PO4-P), total phosphorus …
Indicator Bacteria Concentrations Of Two Northwest Arkansas Streams In Relation To Flow And Season, Dwayne R. Edwards, Mark S. Coyne, Tommy C. Daniel, P. F. Vendrell, J. F. Murdoch, P. A. Moore Jr.
Indicator Bacteria Concentrations Of Two Northwest Arkansas Streams In Relation To Flow And Season, Dwayne R. Edwards, Mark S. Coyne, Tommy C. Daniel, P. F. Vendrell, J. F. Murdoch, P. A. Moore Jr.
Biosystems and Agricultural Engineering Faculty Publications
Concentrations of indicator bacteria such as fecal coliform (FC) and fecal streptococcus (FS) are often used to assess the suitability of waters for their intended use(s) and to allocate resources for water quality improvement measures. There is evidence, however, that concentrations of FC and FS can be influenced by variables such as season and flow rate during sampling, which could lead to biased results. The objective of this study was to assess the impacts of season and flow rate on concentrations of FC and FS. Fecal indicator bacteria concentrations were measured for approximately three years at five sites on two …
Poultry Litter-Treated Length Effects On Quality Of Runoff From Fescue Plots, Dwayne R. Edwards, Philip A. Moore Jr., Tommy C. Daniel, Puneet Srivastava
Poultry Litter-Treated Length Effects On Quality Of Runoff From Fescue Plots, Dwayne R. Edwards, Philip A. Moore Jr., Tommy C. Daniel, Puneet Srivastava
Biosystems and Agricultural Engineering Faculty Publications
Using experimental data and/or mathematical simulation models to identify practices that reduce pollution from manure-treated areas is sometimes perceived as limited by the unknown validity of extrapolating plot-scale data to larger areas and by uncertainties in modeling transport of various pollutants. The objectives of this study were to assess the effect of length of manure treatment on runoff concentrations of poultry litter constituents and to define the modes of transport (particulate versus soluble) for nitrogen (N), phosphorus (P), carbon (C), and solids. Poultry litter was applied to three 1.5- x 18.3-m fescue (Festuca arundinacea Schreb.) plots with runoff collection …
Quality Of Runoff From Four Northwest Arkansas Pasture Fields Treated With Organic And Inorganic Fertilizer, Dwayne R. Edwards, Tommy C. Daniel, John F. Murdoch, Philip A. Moore Jr.
Quality Of Runoff From Four Northwest Arkansas Pasture Fields Treated With Organic And Inorganic Fertilizer, Dwayne R. Edwards, Tommy C. Daniel, John F. Murdoch, Philip A. Moore Jr.
Biosystems and Agricultural Engineering Faculty Publications
Long-term land application of animal manures, even at agronomic rates, can promote accumulation of soil phosphorus (P) which can, in turn, contribute to increased P loadings to downstream waters. The objective of this study was to assess the soil and runoff effects of replacing animal manure as a soil amendment with inorganic fertilizer (ammonium nitrate, NH4NO3) on fields that had been treated previously with animal manures. Runoff from two pairs of small fields (0.57 to 1.46 ha) was sampled from September 1991 to April 1994. All fields had been treated previously with animal manures; after runoff …
Simulation Of Runoff Transport Of Animal Manure Constituents, Yang Wang, Dwayne R. Edwards, Tommy C. Daniel, H. Don Scott
Simulation Of Runoff Transport Of Animal Manure Constituents, Yang Wang, Dwayne R. Edwards, Tommy C. Daniel, H. Don Scott
Biosystems and Agricultural Engineering Faculty Publications
Runoff losses of land-applied animal manure constituents can adversely affect the quality of downstream waters. Reliable mathematical simulation models can help estimate runoff losses of animal manure constituents and identify management measures to reduce these losses. The objective of this study was to develop and calibrate an event-based simulation model to describe the runoff transport of solids (soil and manure particles) and nutrients (nitrogen and phosphorus) from areas treated with animal manure. The resulting model, consisting of linked hydrology, soil/manure transport, and nutrient transport components, is process-oriented and uses measurable parameters to the greatest degree possible. The three components of …
Application Of Simplified Phosphorus Transport Models To Pasture Fields In Northwest Arkansas, Dwayne R. Edwards, C. T. Haan, Andrew N. Sharpley, John F. Murdoch, Tommy C. Daniel, Philip A. Moore Jr.
Application Of Simplified Phosphorus Transport Models To Pasture Fields In Northwest Arkansas, Dwayne R. Edwards, C. T. Haan, Andrew N. Sharpley, John F. Murdoch, Tommy C. Daniel, Philip A. Moore Jr.
Biosystems and Agricultural Engineering Faculty Publications
Runoff transport of phosphorus (P) is often predicted from simple equations with parameters determined from data applicable primarily to row-cropped and fallow cover conditions. The applicability, accuracy, and precision of such P transport prediction equations under pasture situations are less well defined. The objectives of this study were to determine parameters of simplified runoff P transport equations for pasture fields and to assess the accuracy and precision of the equations. Runoff, sediment yield, soluble P transport, and particulate P transport data were collected from four pasture fields in northwestern Arkansas. Runoff event enrichment ratios and extraction coefficients were computed, and …