Open Access. Powered by Scholars. Published by Universities.®
- Publication Year
- Publication
- Publication Type
Articles 1 - 23 of 23
Full-Text Articles in Life Sciences
The Influence Of Intensity Of Tree Thinning On The Redistribution Of Soil Water In Southern African Mopani Veld, G N. Smit, N F.G. Rethman, A Moore, A Le Roux, J S. Swart
The Influence Of Intensity Of Tree Thinning On The Redistribution Of Soil Water In Southern African Mopani Veld, G N. Smit, N F.G. Rethman, A Moore, A Le Roux, J S. Swart
IGC Proceedings (1997-2023)
The investigation was conducted on a densely wooded area in the Mopani veld of South Africa. Six plots were subjected to different intensities of tree thinning, ranging from a totally cleared plot (0 %) to plots thinned to the equivalent of 10%, 20%, 35%, 50% and 75% of the leaf biomass of a control plot (100%). Soil water measurements were taken at six different depths to a depth of 825 mm. The infiltration of rain water and redistribution within the soil profile exhibited marked differences between experimental plots. The soil water was predominantly held at a very shallow depth ( …
Early Spring Surface Runoff From Grassland And Arable Land, S. Hejduk, K. Kasprzak
Early Spring Surface Runoff From Grassland And Arable Land, S. Hejduk, K. Kasprzak
IGC Proceedings (1997-2023)
Surface runoff is regarded as an undesirable phenomenon because it deprives plants and soil of precipitation water and reduces its penetration underground. It is also the cause erosion and flooding. The occurrence and depth of a frozen soil layer is the main factor which determines the amount of surface runoff in winter. A well-developed surface and/or sub-surface layer of frozen soil is practically impenetrable for water. This layer results from ice-forming processes, which are influenced by snow melting due to diurnal fluctuations in temperature in early spring, partial thaws, winter rainfalls, and thermocapillary processes taking place in frozen soil.
Water-Use Efficiency And Infiltration Under Different Rangeland Conditions And Cultivation In A Semi-Arid Climate Of South Africa, Hennie A. Snyman
Water-Use Efficiency And Infiltration Under Different Rangeland Conditions And Cultivation In A Semi-Arid Climate Of South Africa, Hennie A. Snyman
IGC Proceedings (1997-2023)
The objective of this study was to determine the impact of rangeland in different botanical composition classes (good, moderate and poor), on water-use efficiency (WUE: crude protein produced per unit of evapotranspiration) and soilwater content. The same measurements were also made on an undisturbed bare soil surface and soil cultivated twice per annum. Evapotranspiration was determined by quantifying the soil-water balance equation with the aid of runoff plots and soil-water content measurements done by a neutron hydroprobe. Water-use efficiency declined significantly (P ≤ 0.01) with rangeland degradation. Rangeland in good condition averaged a WUE of 0.28 kg crude protein ha …
Analysis Of Infiltration And Surface Runoff In River Njoro Watershed Using A Rainfall Simulator, M. O. Okelo, J. O. Onyando, W. A. Shivoga, C. M. Gichaba, S. N. Miller
Analysis Of Infiltration And Surface Runoff In River Njoro Watershed Using A Rainfall Simulator, M. O. Okelo, J. O. Onyando, W. A. Shivoga, C. M. Gichaba, S. N. Miller
IGC Proceedings (1997-2023)
No abstract provided.
Sustainable And Profitable Grazing Management In A Highly Variable Environment‐Evidence And Insights From A Long Term Grazing Trial In Northern Australia, Peter O’Reagain, John Bushell
Sustainable And Profitable Grazing Management In A Highly Variable Environment‐Evidence And Insights From A Long Term Grazing Trial In Northern Australia, Peter O’Reagain, John Bushell
IGC Proceedings (1997-2023)
No abstract provided.
Analysis Of Infiltration And Surface Runoff In River Njoro Watershed Using A Rainfall Simulator, M. O. Okelo, J. O. Onyando, W. A. Shivoga, C. M. Gichaba, S. N. Miller
Analysis Of Infiltration And Surface Runoff In River Njoro Watershed Using A Rainfall Simulator, M. O. Okelo, J. O. Onyando, W. A. Shivoga, C. M. Gichaba, S. N. Miller
IGC Proceedings (1997-2023)
No abstract provided.
Grassland And Water Resources: Recent Trends And Future Challenges In Temperate Zones, Benoît Marc
Grassland And Water Resources: Recent Trends And Future Challenges In Temperate Zones, Benoît Marc
IGC Proceedings (1997-2023)
No abstract provided.
Rangeland Management And Hydrology, K. Wood, H. Rubio, C. Wood
Rangeland Management And Hydrology, K. Wood, H. Rubio, C. Wood
IGC Proceedings (1997-2023)
No abstract provided.
Effects Of Slope And Defoliation Intensity On The Effectiveness Of Desert Wheatgrass For Reduced Runoff And Soil Erosion Under Simulated Rainfall, Haitao Zuo, Juying Wu
Effects Of Slope And Defoliation Intensity On The Effectiveness Of Desert Wheatgrass For Reduced Runoff And Soil Erosion Under Simulated Rainfall, Haitao Zuo, Juying Wu
IGC Proceedings (1997-2023)
No abstract provided.
Effects Of Biochar Treatment Of Municipal Biosolids And Horse Manure On Quality Of Runoff From Fescue Plots, Rachel Williams, Dwayne R. Edwards
Effects Of Biochar Treatment Of Municipal Biosolids And Horse Manure On Quality Of Runoff From Fescue Plots, Rachel Williams, Dwayne R. Edwards
Biosystems and Agricultural Engineering Faculty Publications
Land-applied horse manure and municipal biosolids can increase nutrient and bacteria concentrations in runoff. Biochar has been demonstrated to have beneficial impacts on nutrient retention and runoff quality when used to treat other land-applied organic soil amendments (e.g., poultry manure). The objective of this study was to evaluate the effects of biochar addition to horse manure and municipal biosolids on runoff concentrations of nutrients and fecal coliforms. Biochar was added at 5% to 8% (wet basis) to horse manure and biosolids that were applied to 2.4 m x 6.1 m fescue plots followed by application of simulated rainfall (102 mm …
Effects Of Chemical Amendments To Swine Manure On Runoff Quality, Elizabeth L. Bullock, Dwayne R. Edwards, Phillip A. Moore Jr., Richard S. Gates
Effects Of Chemical Amendments To Swine Manure On Runoff Quality, Elizabeth L. Bullock, Dwayne R. Edwards, Phillip A. Moore Jr., Richard S. Gates
Biosystems and Agricultural Engineering Faculty Publications
Land-applied swine manure can be an environmental concern when runoff losses of manure constituents occur. The use of chemical amendments to mitigate these losses has been investigated for poultry litter, but materials such as swine manure have received less attention in this context, particularly at the plot scale or larger. The objective of this experiment was to evaluate the impacts of aluminum sulfate (alum; Al2(SO4)3), aluminum chloride (AlCl3), and ferric chloride (FeCl3) addition on runoff of selected constituents of land-applied swine manure. Manure was collected from feeder pigs fed a …
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 …
Runoff From Fescue Plots Treated With Trimec, Cristopher G. Moss, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams
Runoff From Fescue Plots Treated With Trimec, Cristopher G. Moss, Dwayne R. Edwards, Stephen R. Workman, R. Michael Williams
Biosystems and Agricultural Engineering Faculty Publications
Runoff of herbicides can promote adverse impacts in receiving waters. The objective of this study was to assess the effects of rainfall delay, herbicide application rate, rainfall intensity, and pre-application rainfall on runoff of TRIMEC (a combination of 2,4-D, dicamba, and mecoprop), a herbicide that is commonly used in central Kentucky. The levels of rainfall delay were 0, 2, and 4 d following application; and the levels of herbicide application rate were 0, 0.5, 1 and 2 times the recommended rate. Simulated rainfall was applied at intensities of 64, 102, and 140 mm h-1; and the depths of …
Modeling Surface And Subsurface Pesticide Transport Under Three Field Conditions Using Przm-3 And Gleams, Robert W. Malone, Richard C. Warner, Stephen R. Workman, Matt E. Byers
Modeling Surface And Subsurface Pesticide Transport Under Three Field Conditions Using Przm-3 And Gleams, Robert W. Malone, Richard C. Warner, Stephen R. Workman, Matt E. Byers
Biosystems and Agricultural Engineering Faculty Publications
Contaminant transport models should be evaluated over a wide range of conditions to determine their limitations. The models PRZM and GLEAMS have been evaluated many times, but few studies are available in which predicted movement in runoff and percolate were simultaneously evaluated against field data. Studies of this type are essential because pesticide leaching and runoff are mutually dependent processes. For this reason, PRZM-3 and GLEAMS were evaluated for their ability to predict metribuzin concentrations in runoff, sediment, subsurface soil, and pan lysimeters under three field conditions (yard waste compost amended, no-till, and conventional-till) on a Lowell silt loam soil. …
Quality Of Runoff From Plots Treated With Municipal Sludge And Horse Bedding, Elizabeth L. Busheé, Dwayne R. Edwards, Philip A. Moore Jr.
Quality Of Runoff From Plots Treated With Municipal Sludge And Horse Bedding, Elizabeth L. Busheé, Dwayne R. Edwards, Philip A. Moore Jr.
Biosystems and Agricultural Engineering Faculty Publications
Land application of horse stall bedding and municipal sludge can increase runoff concentrations of nutrients, organic matter, and bacteria as well as steroidal hormones such as estrogen. Concentrations of materials in runoff from sites treated with animal manure can be reduced by aluminum sulfate, or alum [Al2(SO4)3•14H2O] treatment. The objectives of this study were to assess plots treated with horse stall bedding or municipal sludge for: (a) runoff quality [concentrations of nitrate nitrogen (NO3-N), ammonia nitrogen (NH3-N), orthophosphate-phosphorus (PO4-P), fecal coliform (FC), chemical oxygen demand (COD) …
Validating A Vegetative Filter Strip Performance Model, Puneet Srivastava, Thomas A. Costello, Dwayne R. Edwards, James A. Ferguson
Validating A Vegetative Filter Strip Performance Model, Puneet Srivastava, Thomas A. Costello, Dwayne R. Edwards, James A. Ferguson
Biosystems and Agricultural Engineering Faculty Publications
Vegetative filter strips (VFS) reduce losses of nutrients, solids, and other materials from land area treated with fertilizers and manures. A number of models are available that simulate nutrient and sediment transport in VFS. While VFS effectiveness is considered to depend on lengths of pollutant source area and VFS areas, few published studies have tried to validate these models using variable pollutant source area and VFS area. The objective of this study was to validate an event-based nutrient transport model (Chaubey et al., 1995) that simulates soluble nutrient transport in VFS. This model links three sub-models: modified Green-Ampt infiltration, non-linear …
Vegetative Filter Strip Removal Of Metals In Runoff From Poultry Litter-Amended Fescuegrass Plots, Dwayne R. Edwards, P. A. Moore Jr., Tommy C. Daniel, Puneet Srivastava, D. J. Nichols
Vegetative Filter Strip Removal Of Metals In Runoff From Poultry Litter-Amended Fescuegrass Plots, Dwayne R. Edwards, P. A. Moore Jr., Tommy C. Daniel, Puneet Srivastava, D. J. Nichols
Biosystems and Agricultural Engineering Faculty Publications
Runoff from land areas amended with poultry (Gallus gallus domesticus) manure can contain elevated concentrations of metals such as Cu, Fe, and Zn. Vegetative filter strips (VFS) can reduce runoff concentrations of animal manure components, but reported studies have typically focused on nutrients and solids rather than metals. This experiment assessed the impact of VFS length (0 to 12 m) on concentrations and mass losses of Cu, Fe, K, Na, Ni, and Zn in runoff from fescuegrass (Festuca arundinacea Schreb.) plots (1.5 m wide × 6 and 12 m long) treated with poultry litter. The runoff was produced from simulated …
Vegetative Filter Strip Design For Grassed Areas Treated With Animal Manures, Dwayne R. Edwards, Tommy C. Daniel, Philip A. Moore Jr.
Vegetative Filter Strip Design For Grassed Areas Treated With Animal Manures, Dwayne R. Edwards, Tommy C. Daniel, Philip A. Moore Jr.
Biosystems and Agricultural Engineering Faculty Publications
Vegetative filter strips (VFS) are a low-cost management option that have been demonstrated to be effective in reducing runoff transport of fertilizer constituents applied to grassed areas (pasture or meadow). Runoff quality studies involving fertilizers applied to grassed areas suggest that VFS can be designed by assuming that (1) only infiltration is responsible for pollutant removal, (2) the first post-application runoff event is most important from a water quality perspective (enabling a design event approach), and (3) no pollutant build-up that degrades VFS performance will occur. The purpose of this study was to develop a VFS design algorithm for grassed …
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 …
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 …
Use Of Riparian Vegetated Filter Strips To Reduce Nitrate And Fecal Contamination In Surface Water, Mark S. Coyne, Robert L. Blevins, Rebecca A. Gilfillen
Use Of Riparian Vegetated Filter Strips To Reduce Nitrate And Fecal Contamination In Surface Water, Mark S. Coyne, Robert L. Blevins, Rebecca A. Gilfillen
KWRRI Research Reports
This research assessed fecal bacteria trapping in surface runoff by grass filters and their potential to enhance NO3- removal via denitrification. Grass filter strips 9.0 m long trapped over 99% of the soil in surface runoff in 1992. Fecal coliform removal was less than 75%. In 1993, 9.0 and 4.5 m grass filter strips trapped 99 and 95% of the sediment, respectively. Fecal coliform trapping efficiency was 90% in 9.0 m grass filters and 75% in 4.5 m filters. Fecal streptococci trapping efficiency was 77% in 9.0 m grass filters and only 56% in 4.5 m filters. Fecal …
Potential Of Surface Water Contamination From Three Triazine Herbicides, William W. Witt, Kip W. Sander
Potential Of Surface Water Contamination From Three Triazine Herbicides, William W. Witt, Kip W. Sander
KWRRI Research Reports
The movement of atrazine, cyanazine, and simazine from the site of application was monitored under conventional, reduced, and no-tillage conditions. Less water and soil was lost from the no-tillage and reduced tillage conditions. Conventional tillage conditions had about 66,000 L/ha runoff in 1986-87 and about 123,000 L/ha runoff in 1987-88. Seasonal rainfall was 885 mm in 1986-87 and 397 mm in 1987-88. The rainfall intensity was greater during the first two events in 1987 than the corresponding events in 1986. The first rainfall event in 1986 accounted for 91, 89, and 78% of the total seasonal loss of atrazine, cyanazine, …
Abatement Of Nitrate Pollution In Groundwater And Surface Runoff From Cropland Using Legume Cover Crops With No-Till Corn, M. Scott Smith, Jac J. Varco
Abatement Of Nitrate Pollution In Groundwater And Surface Runoff From Cropland Using Legume Cover Crops With No-Till Corn, M. Scott Smith, Jac J. Varco
KWRRI Research Reports
Agricultural practices can have a significant impact on water quality. The effects of leguminous winter cover crops on leaching of NO-3; from soil have been investigated in this project. Legume cover crops, by fixation of atmospheric N, can reduce the amount of fertilizer N required to produce summer grain crops. The methods initially used to evaluate cover crop effects on No; transport included suction probe lysimeters and measurement of NO-3; in soil samples collected to a depth of 90 cm. These measurements demonstrated extreme spatial variability in NO-3; distribution and water …