A5019752954- Soil and Water Nutrient Dynamics
- Hydrology and Watershed Management Studies
- Soil erosion and sediment transport
- Fish Ecology and Management Studies
- Water Quality and Resources Studies
- Groundwater flow and contamination studies
- Hydrology and Sediment Transport Processes
- Wastewater Treatment and Nitrogen Removal
- Turfgrass Adaptation and Management
- Aquatic Ecosystems and Phytoplankton Dynamics
- Pesticide and Herbicide Environmental Studies
- Phosphorus and nutrient management
- Freshwater macroinvertebrate diversity and ecology
- Soil Carbon and Nitrogen Dynamics
- Soil and Unsaturated Flow
- Groundwater and Isotope Geochemistry
- Peatlands and Wetlands Ecology
- Constructed Wetlands for Wastewater Treatment
- Urban Stormwater Management Solutions
- Water Quality and Pollution Assessment
- Aquatic Invertebrate Ecology and Behavior
- Plant Water Relations and Carbon Dynamics
- Reservoir Engineering and Simulation Methods
- Soil Moisture and Remote Sensing
- Water Quality Monitoring and Analysis
Agricultural Research Service
2016-2025
United States Department of Agriculture
2007-2024
Rush University Medical Center
2023
United States Department of State
2023
University of Arkansas System
2019
Kansas State University
2019
Delta Water Management Research Unit
2019
Iowa State University
2019
University of Arkansas at Fayetteville
2018
Grassland, Soil and Water Research Laboratory
1999-2017
The midwestern United States offers some of the most productive agricultural soils in world. Given cool humid climate, much region would not be able to support agriculture without subsurface (tile) drainage because high water tables may damage crops and prevent machinery usage fields at critical times. Although is designed remove excess soil as quickly possible, it can also rapidly transport agrochemicals, including phosphorus (P). This paper illustrates potential importance tile for P...
Phosphorus (P) transport from agricultural fields continues to be a focal point for addressing harmful algal blooms and nuisance algae in freshwater systems throughout the world. In humid, poorly drained regions, attention has turned P delivery through subsurface tile drainage. However, research on contributions of drainage watershed-scale losses is limited. The objective this study was evaluate long-term movement its manifestation at watershed outlet. Discharge data associated...
Two methods of simulating excess rainfall were compared on a large basin with multiple rain gages. The SCSdaily curve number method (CN) was the Green-Ampt Mein-Larson (GAML) Goodwin CreekWatershed (GCW). GCW is 21.3 km2 in area and has 32 gages located within surrounding watershed. Themodel used Soil Water Assessment Tool (SWAT). SWAT comprehensive watershed scale model developed tosimulate management impacts water, sediment, chemical yields for ungaged basins. modified to acceptbreakpoint...
In the early to mid-1990s, Lake Erie was regarded as one of great water quality success stories stemming from Clean Water Act. Annual total phosphorus (TP) loading lake decreased nearly 30,000 t (33,069 tn) in late-1960s less than 11,000 (12,125 by 1990 (Richards and Baker 1993). These reductions TP were achieved through permitting point sources conservation efforts decrease sediment loss agricultural fields. While loads have remained relatively stable since soluble (SP) been steadily...
Abstract Elevated phosphorus (P) concentrations in subsurface drainage water are thought to be the result of P bypassing soil matrix via macropore flow. The objectives this study were quantify event delivery tile drains flow paths during storm events and determine effect tillage practices on tiles. Tile discharge, total dissolved (DP) (TP) concentrations, stable oxygen deuterium isotopic signatures measured from two adjacent tile‐drained fields Ohio, USA seven spring storms. Fertilizer was...
Sustainable intensification is an emerging model for agriculture designed to reconcile accelerating global demand agricultural products with long-term environmental stewardship. Defined here as increasing production while maintaining or improving quality, sustainable hinges upon decision-making by producers, consumers, and policy-makers. The Long-Term Agroecosystem Research (LTAR) network was established inform these decisions. Here we introduce the LTAR Common Experiment, through which...
Agriculture in the United States must respond to escalating demands for productivity and efficiency, as well pressures improve its stewardship of natural resources. Growing global population changing diets, combined with a greater societal awareness agriculture's role delivering ecosystem services beyond food, feed, fiber, energy production, require comprehensive perspective on where how US agriculture can be sustainably intensified, that is, made more productive without exacerbating local...
Abstract In agricultural watersheds, shifting climate and hydrologic patterns present an immediate future risk to both farm productivity downstream aquatic ecosystems. Here, our objective was evaluate long‐term spatiotemporal trends in rainfall amount intensity within the Maumee River‐Lake Erie system quantify effects of on streamflow phosphorus loading. Across watershed, annual increased by 102 ± 115 mm (11 13%) from 1975–2017. Heavy (25.4–76.2 mm) very heavy (>76.2 accounted for most...
Abstract Agricultural phosphorus (P) losses to surface water bodies remain a global eutrophication concern, despite the application of conservation practices on farm fields. Although it is generally agreed upon that use multiple (“stacking”) will lead greater improvements quality, this may not be cost effective farmers, reducing likelihood adoption. At present, wholesale recommendations are given; however, specific in certain environments (e.g., no‐till with application, cover crops) and can...
Abstract Seasonal cracking of the soil matrix results in poor estimates runoff and infiltration by simulation models due to changing storage conditions. In this study, surface elevation changes were measured every two weeks crack volume was calculated for a two‐year period at USDA‐Agricultural Research Service, Riesel Y‐2 watershed central Texas. Soil anchors placed triplicate depths 0·15, 0·45, 0·90, 1·50 2·5 m relative movement from monument 4·5 measured. translated into assuming...
Surendran Nair, Sujithkumar, Kevin W. King, Jonathan D. Witter, Brent L. Sohngen, and Norman R. Fausey, 2011. Importance of Crop Yield in Calibrating Watershed Water Quality Simulation Tools. Journal the American Resources Association (JAWRA) 47(6):1285–1297. DOI: 10.1111/j.1752-1688.2011.00570.x Abstract: Watershed-scale water-quality simulation tools provide a convenient economical means to evaluate environmental impacts conservation practices. However, confidence tool's ability accurately...
Abstract SPAtially Referenced Regression on Watershed models developed for the Upper Midwest were used to help evaluate nitrogen‐load reductions likely be achieved by a variety of agricultural conservation practices in Mississippi‐Ohio River Basin ( UMORB ) and compare these 45% reduction proposed remediate hypoxia Gulf Mexico GoM ). Our results indicate that nitrogen‐management (improved fertilizer management cover crops) fall short achieving this goal, even if adopted all cropland region....
The prevalence of anthropogenic drainage systems in intensively cropped areas across North America combined with the degradation important freshwater resources these regions has created a critical intersection where understanding phosphorus (P) transport waters is vital. In this study, drainage-associated nutrient load data were retrieved and quantitatively analyzed to develop more comprehensive P loading crop yield impacts agronomic management practices within drained landscapes. Using...
Core Ideas Soil test phosphorus remains an important factor in studying dissolved reactive P loss. Identifying higher risk fields with STP could inform future management practices to reduce DRP was linearly related concentration loads tile‐drained fields. Monitoring addition implementing other BMPs should be considered decrease Harmful and nuisance algal blooms resulting from excess (P) have placed agriculture the spotlight of water quality debate. Sixty‐eight site years loading data...
The Western Lake Erie Basin (WLEB) was inundated with precipitation during June and July 2015 (two to three times greater than historical averages), which led significant nutrient loading the largest in-lake algal bloom on record. Using discharge concentration data from spatial scales (0.18-16,000 km), we contrast patterns in nitrate (NO-N) dissolved reactive phosphorus (DRP) dynamics discuss potential management implications. Across all scales, NO-N steadily declined each subsequent...
Agricultural phosphorus (P) loss has been linked to the eutrophication of surface water bodies throughout world. As a result, minimizing offsite P transport become priority in many rural watersheds. In US Midwest and other subsurface tile-drained regions, there is critical need identify nutrient management practices that decrease both discharge. An edge-of-field (EOF) network monitoring 38 agricultural fields was established northwest Ohio, United States, quantify impacts prevailing novel...