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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, …
Responses Of Hydrological Processes And Water Quality To Land Use/Cover (Lulc) And Climate Change In A Coastal Watershed, Ruoyu Wang
Ruoyu Wang
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 …
Runoff Production In The Upper Rio Chagres Watershed, Panama, Fred Ogden
Runoff Production In The Upper Rio Chagres Watershed, Panama, Fred Ogden
Fred L. Ogden
Runoff production in tropical watersheds is governed by a wide variety of potential sources and there have been few rigorous studies to date. The 414 km2 upper Río Chagres basin offers a unique opportunity to better understand the runoff production mechanisms in tropical watersheds through data analysis and modeling with rainfall and runoff data. Flow data and tipping bucket rain gage data are available at both the basin outlet (Chico gage) and for an 80.6 km2 internal basin location (Piedras gage). Modeling is performed using the Sacramento Soil Moisture Accounting Model (SAC-SMA), calibrated using data from 2000 and verified using …
Green And Ampt Infiltration With Redistribution, Fred L. Ogden
Green And Ampt Infiltration With Redistribution, Fred L. Ogden
Fred L. Ogden
Distributed, physically based watershed and irrigation advance models require robust infiltration estimation capabilities. The empirical Green and Ampt (GA) equation of infiltration is a popular method for estimating infiltration. The GA parameters have physical basis and considerable prior research has focused on relating these parameters to soil textural classification. However, the original GA method is limited in that it is applicable only for a single ponding period. An explicit Green and Ampt redistribution (GAR) technique is developed herein to estimate interstorm redistribution of soil water and allow multiple ponding simulations using the GA methodology. Soil water redistribution during interponding periods …