Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 19 of 19 for “"nitrogen losses"”.
-
Heterogeneous Nitrogen Losses: Cost-Effectiveness Analysis of Changes in Management Across South Dakota
<p>The loss of nitrogen fertilizer into the atmosphere and waterways is of increasing concern for citizens and policy makers. This is particularly relevant for hypoxia in rivers, lakes, and oceans, but also relevant for policy makers in reducing the increasing concentration of greenhouse gases …
-
Evaluating effects of water quality BMPs on nitrate-nitrogen losses and crop yield at field and watershed scales
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2023-12-01
-
Nutrient Management Planning on Virginia Livestock Farms: Impacts and Opportunities for Improvement
… analysis of the ability to reduce potential nitrogen loadings to water bodies through the implementation of nutrient management plans on livestock farms. Study results indicate that nutrient management plans do result in significant reductions while maintaining or increasing farm income. …
-
Financial costs and economic tradeoffs of alternative manure management policies on dairy and dairy/poultry farms in Rockingham County, Virginia
… incorporating all manure (INCORP), limit nitrogen applications to agronomic recommendations (NLIMIT), and phosphorus applications limited to crop removals (PLIMIT), on representative 60, 100, and 150-cow dairy and dairy/poultry farms. Current nutrient applications are manure-based, with …
-
Risk Analysis of Adopting Conservation Practices on a Representative Peanut-Cotton Farm in Virginia
… is to evaluate the costs of reducing pesticide, nitrogen, phosphorus, and sediment losses of a representative risk-neutral and risk-averse peanut-cotton farmer in Southeast Virginia. Five currently popular rotations and eight alternative conservation rotations are evaluated for the representative …
-
Modeling nitrogen transport with the ANSWERS model
… has been identified as the primary source of nitrogen and sediment, and a significant source of phosphorus in the Chesapeake Bay. These pollutants, whether from point or nonpoint sources, have been found to be the primary cause of declining water quality in the Bay. Numerous studies have …
-
Effects of Western Spruce Budworm Herbivory on Forest Soils and Litter Decomposition in Central Washington
… to the forest floor which are broken down into nitrogen, phosphorous, and other elements to be recycled into biomass. Western spruce budworms are defoliators native to the central Cascades and their herbivory could increase the decomposition rate of forest materials by adding essential nutrients …
-
A Process-Based Nutrient Model for the Bedded Manure Pack of Confined Beef Systems
… evaluated the source of volatilized ammonia nitrogen from beef cattle manure. Isotope ratio mass spectrometry was used to determine the origin of aerial ammonia nitrogen losses (urine or fecal material) from the relative isotopic abundance of nitrogen in the 15N -labeled slurry mixture. On …
-
The effects of a hypocaloric diet, with varying protein/carbohydrate ratios, on the nitrogen balance of male weightlifters
… sweat samples were taken for each subject. Fecal nitrogen losses were estimated and added to urine and sweat values for daily nitrogen excretion. There was a significant difference in nitrogen balance between the groups over time. Nitrogen balance was positive for the HP/MC group (4.13 g/d) and …
-
Frontiers in alley cropping: Transformative solutions for temperate agriculture
… food-producing AC to mitigate unintended nitrogen losses in a side-by-side field experiment with row crop agriculture. I show that transitioning to AC can rapidly tighten the nitrogen cycle even during establishment years. Finally, I evaluate the economic competitiveness of the most common …
-
Wastewater renovation with soil depth as influenced by additional treatment of septic tank effluent
… fecal coliforms, 34 and 44% reduction in total nitrogen, and a 60 and 94% reduction in BOD₅, respectively. Fecal coliforms were present only in soil leachate from the 15 and 30 cm soil depths receiving septic tank effluent and the 15 cm depth that received constructed wetland effluent. Average …
-
The effects of atrazine on nitrogen cycling in a freshwater wetland microcosm
… atrazine to a wetland microcosm will disrupt the nitrogen cycle by inhibiting nitrifying and denitrifying bacteria. The inhibition or absence of functional groups of bacteria will limit the ability of the wetland to remove nutrients and herbicides, thus increasing nitrogen levels in non-point …
-
ASSESSING THE IMPACTS OF ORGANIC AMENDMENTS ON DISTURBED SOIL PROPERTIES, WATER QUALITY AND VEGETATION GROWTH
… (tap water) phosphorus, caused significant nitrogen losses, exceeding typical stormwater concentrations by 40-200 times. Leaf compost also contributed to nitrogen leaching but only during the initial stages. Mulch reduced nutrient loss but caused limited vegetative cover. The study found …
-
Nitrogen transport and dynamics in grass filter strips
… of a model to describe the dynamics and fate of nitrogen (N) in VFSs. The experiment had a completely randomized design, with 3 treatments and 2 replicates per treatment. The treatments were 3 VFS lengths: 0, 4.27, and 8.5 m VFSs. The distribution free Kruskal-Wallis test indicated that the …
-
Effect of Bioaugmentation Product BiOWiSH® AQUA™ on Nitrogen Removal in Wastewater
… removal (BNR) from wastewater, and specifically nitrogen removal, is a growing concern to wastewater dischargers such as municipalities. Excess nutrients in effluent can create problems such as eutrophication, toxicity to aquatic life, and dissolved oxygen depletion in receiving waters. BNR …
-
Development and application of a microbial reliability model to analyze denitrifying biofilter stability
The use of nitrogenous fertilizers to amend soil fertility has had a drastic effect on the global nitrogen cycle as excess nitrogen has contaminated surface waters, leading to marine hypoxic zones. One of the largest contributors to nitrogen loads in surface waterways is subsurface agricultural …
-
Genomic improvement of nitrogen utilization efficiency in maize
… application rates to boost yields. Consequently, nitrogen (N) use in the United States has increased nearly six fold in the last fifty years to more than 13 million tons applied in 2014, an increase that mirrors worldwide trends. The production of N fertilizer is dependent on energy inputs to …
-
Investigating the feasibility and logistics of decentralized urine treatment for resource recovery
… be completely depleted. Moreover, methods of nitrogen production such as the Haber‐Bosch process contribute largely towards global energy expenditure and greenhouse gas emissions. Considering this, researchers have aimed to investigate methods of recovering phosphorus and nitrogen to help cope …