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Articles 1 - 9 of 9
Full-Text Articles in Water Resource Management
Evaluating And Predicting Agricultural Management Effects Under Tile Drainage Using Modified Apsim, Robert W. Malone, N. Huth, P. S. Carberry, Liwang Ma, Thomas C. Kaspar, Douglas L. Karlen, T. Meade, Ramesh S. Kanwar, Philip Heilman
Evaluating And Predicting Agricultural Management Effects Under Tile Drainage Using Modified Apsim, Robert W. Malone, N. Huth, P. S. Carberry, Liwang Ma, Thomas C. Kaspar, Douglas L. Karlen, T. Meade, Ramesh S. Kanwar, Philip Heilman
Douglas L Karlen
An accurate and management sensitive simulation model for tile-drained Midwestern soils is needed to optimize the use of agricultural management practices (e.g., winter cover crops) to reduce nitrate leaching without adversely affecting corn yield. Our objectives were to enhance the Agricultural Production Systems Simulator (APSIM) for tile drainage, test the modified model for several management scenarios, and then predict nitrate leaching with and without winter wheat cover crop. Twelve years of data (1990–2001) from northeast Iowa were used for model testing. Management scenarios included continuous corn and corn–soybean rotations with single or split N applications. For 38 of 44 observations, …
Corn-Soybean And Alternative Cropping Systems Effects On No 3 -N Leaching Losses In Subsurface Drainage Water, Rameshwar S. Kanwar, Richard M. Cruse, Mohammadreza Ghaffarzadeh, Allah Bakhsh, Douglas Karlen, Theodore B. Bailey
Corn-Soybean And Alternative Cropping Systems Effects On No 3 -N Leaching Losses In Subsurface Drainage Water, Rameshwar S. Kanwar, Richard M. Cruse, Mohammadreza Ghaffarzadeh, Allah Bakhsh, Douglas Karlen, Theodore B. Bailey
Douglas L Karlen
Alternative cropping systems can improve resource use efficiency, increase corn grain yield, and help in reducing negative impacts on the environment. A 6-yr (1993 to 1998) field study was conducted at the Iowa State University’s Northeastern Research Center near Nashua, Iowa, to evaluate the effects of non-traditional cropping systems [strip inter cropping (STR)-corn (Zea mays L.)/soybean (Glycine max L.)/oats (Avina sativa L.)]; alfalfa rotation (ROT)-3-yr (1993 to 1995) alfalfa (Medicago sativa L.) followed by corn in 1996, soybean in 1997, and oats in 1998), and traditional cropping system (corn after soybean (CS) and soybean after corn (SC) on the flow …
Cropping System Effects On No3-N Loss With Subsurface Drainage Water, Allah Bakhsh, Rameshwar S. Kanwar, Theodore B. Bailey, Cynthia A. Cambardella, Douglas Karlen, Thomas S. Colvin
Cropping System Effects On No3-N Loss With Subsurface Drainage Water, Allah Bakhsh, Rameshwar S. Kanwar, Theodore B. Bailey, Cynthia A. Cambardella, Douglas Karlen, Thomas S. Colvin
Douglas L Karlen
An appropriate combination of tillage and nitrogen management practices will be necessary to develop sustainable farming practices. A six–year (1993–1998) field study was conducted on subsurface–drained Clyde–Kenyon–Floyd soils to quantify the impact of two tillage systems (chisel plow vs. no tillage) and two N fertilizer management practices (preplant single application vs. late–spring soil test based application) on nitrate–nitrogen (NO3–N) leaching loss with subsurface drain discharge from corn (Zea mays L.) soybean (Glycine max L.) rotation plots. Preplant injected urea ammonium nitrate solution (UAN) fertilizer was applied at the rate of 110 kg ha–1 to chisel plow and no–till corn plots, …
Water Quality Effects Of Cellulosic Biofuel Crops Grown On Marginal Land, Ruoyu Wang
Water Quality Effects Of Cellulosic Biofuel Crops Grown On Marginal Land, Ruoyu Wang
Ruoyu Wang
Responses Of Hydrological Processes And Water Quality To Land Use/Cover (Lulc) And Climate Change In A Coastal Watershed, Ruoyu Wang
Ruoyu Wang
Pilot Study Of Greater Boston Drinking Water Quality Changes - Impacts Of Ozonation And Distribution System, Irvine W. Wei, Xin (Cindy) Huang, Windsor Sung
Pilot Study Of Greater Boston Drinking Water Quality Changes - Impacts Of Ozonation And Distribution System, Irvine W. Wei, Xin (Cindy) Huang, Windsor Sung
Irvine W. Wei
The Massachusetts Water Resources Authority (MWRA) provides drinking water to 2.2 million people in Greater Boston. To ensure good water quality without filtration, the MWRA is about to replace chlorination with ozonation as the primary disinfection at the new Walnut Hill Water Treatment Plant, scheduled to be on-line in 2005. The objective of this study was to understand the influence of ozonation on monochloramine decay and pH change in the MWRA system. The influence of the distribution system, which consists of old cast-iron pipes, on the ozonated water was also investigated. A pilot plant, including a simulated distribution system with …
Phytoplankton And Zooplankton: In Lakes Erie, Lake Huron And Lake Michigan: 1984, Joseph Makarewicz
Phytoplankton And Zooplankton: In Lakes Erie, Lake Huron And Lake Michigan: 1984, Joseph Makarewicz
Joseph C Makarewicz
With the acknowledgement that biological monitoring was fundamental to charting ecosystem health (Great Lakes Water Quality Agreement 1978), EPA's program was developed for Lakes Erie, Huron and Michigan to: 1) monitor seasonal patterns, ranges of abundance and, in general, structure of the phytoplankton and zooplankton communities; 2) relate the biological components to variations in the physical, nutrient and biological environment; and 3) assess the annual variance to allow better long-term assessments of trophic structure and state. Several offshore stations (9-11) on several cruises (9-11) during the spring, summer and autumn of 1984 and winter of 1985 were sampled. By examining …
The Anthropogenic Influence On Cuejdi River Water Quality, Andreea Ghiurcă, Andreea Lămășanu, Florin C. Mihai
The Anthropogenic Influence On Cuejdi River Water Quality, Andreea Ghiurcă, Andreea Lămășanu, Florin C. Mihai
Florin C MIHAI
Water pollution is caused in rural areas, especially by uncontrolled waste deposits located in river bed and in urban areas is discharged, irregular, untreated sewage. The Cuejdiu River is a tributary of the Bitriţa River in the left side, with a total length of 24 km. Evaluation of water quality of the Cuejdiu River was achieved by processing the results obtained from tests analyzed for 30 samples, taken on March 17, 2012, between the mouth of the River Bestriţa and up to the exit of the village Cuiejdi. Analysis of water samples were performed in the laboratory of the Department …
Modeling Bacteria Fate And Transport In Watersheds To Support Tmdls, Brian L. Benham, Claire Baffaut, Rebecca W. Zeckoski, Kyle R. Mankin, Yakov A. Pachepsky, Ali M. Sadeghi, Kevin M. Brannan, Michelle L. Soupir, Matthew J. Habersack
Modeling Bacteria Fate And Transport In Watersheds To Support Tmdls, Brian L. Benham, Claire Baffaut, Rebecca W. Zeckoski, Kyle R. Mankin, Yakov A. Pachepsky, Ali M. Sadeghi, Kevin M. Brannan, Michelle L. Soupir, Matthew J. Habersack
Michelle L. Soupir
Fecal contamination of surface waters is a critical water-quality issue, leading to human illnesses and deaths. Total Maximum Daily Loads (TMDLs), which set pollutant limits, are being developed to address fecal bacteria impairments. Watershed models are widely used to support TMDLs, although their use for simulating in-stream fecal bacteria concentrations is somewhat rudimentary. This article provides an overview of fecal microorganism fate and transport within watersheds, describes current watershed models used to simulate microbial transport, and presents case studies demonstrating model use. Bacterial modeling capabilities and limitations for setting TMDL limits are described for two widely used watershed models (HSPF …