Excessive application of swine manure to a field over long durations can increase nitrate-nitrogen (NO 3 -N) leaching as a result of accumulation of more nutrients in the root zone than the subsequent crops may need. The objective of this study was to use the GLEAMS (V.2.1) model to compare measured versus simulated effects of swine manure application with urea-ammonium-nitrate (UAN) on subsurf...

61 S in the Gulf of Mexico have documented a large area with seasonally depleted O2 levels (<2 mg L−1). Most aquatic species cannot survive at such low O2 levels. A reduction in NO3–N loading by 30% was initially recommended to reduce hypoxia in the Gulf of Mexico (Mitsch et al., 1999). Following a scientifi c reassessment that recommended a reduction of 45% (USEPA, 2007), the USEPA developed a...

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options. USING RZWQM TO PREDICT HERBICIDE LEACHING LOSSES IN SUBSURFACE DRAINAGE WATER Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org Citation: Transactions of the ASAE. Vol. 47(5): 1415-1426 . (doi: 10.13031/2013.17621) ...

The term “karst” applies to a distinctive type of landscape that develops from the dissolving action of water on soluble bedrock (Figure 11.1)—primarily limestone and marble but also dolostone, gypsum and halite. Karst landscapes are characterized by fluted and pitted rock surfaces, shafts, sinkholes, sinking streams, springs, subsurface drainage systems, and caves. The unique features and thre...

The performance of an innovative pilot-scale subsurface flow compost wetland for the attenuation of zinc in mine drainage was investigated. The particular novelty of the system, which operated under ambient environmental conditions, was the short hydraulic residence time (HRT) of 7.5 – 14.5 hours. Short HRT is crucial because it reduces absolute wetland size and construction cost, which can be ...

Subsurface (tile) drainage, while necessary for viable agricultural crop production in the humid, poorly drained regions of world, has been linked to offsite nutrient transport, culminating harmful algal blooms and hypoxia downstream waterbodies. Drainage water management (DWM), also known as controlled promoted a method reduce nitrogen (N) phosphorus (P) loss from field scale tile drainage; ho...

tificial drainage, however, are well documented and include sediment, nutrient (N, P), and pesticide delivery Nitrate losses through subsurface drains in agricultural fields pose to surface waters via subsurface drain lines (Gast et al., a serious threat to surface water quality. Substantial reductions in drainage losses of NO3–N can occur with alfalfa (Medicago sativa 1978; Logan et al., 1980,...

Agriculture has long been considered a great source of nitrogen (N) to surface waters and major cause eutrophication. Thus, management practices at the farm-scale have since attempted mitigate N losses, although often limited in tile-drained agricultural catchments, which speed up transport, while minimizing natural removal landscape. In this context, surface-flow constructed wetlands (SFWs) pa...