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Showing 1 to 20 of 27 for “"Nitrogen loss"”.
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Nitrogen loss inhibitors in intensively managed winter wheat
Several potential pathways exist for significant nitrogen loss from nitrogen fertilizer applied to winter wheat in Virginia. A number of materials have been previously identified which inhibit steps in one or more of these loss pathways. Ammonium polyphosphate, ammonium thiosulfate, dicyandiamide, …
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Overhead sprinkler irrigation strategies to reduce water and nitrogen loss from container-grown plants
The overall objective of this study was to determine the influence of intermittent water application via overhead irrigation on water and N leaching, substrate water distribution, and plant growth in a pine bark substrate. Intermittent irrigation was defined as the application of a plants' daily …
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The organic nature and atmosphere-climate dependency of nitrogen loss from forest watershed ecosystems
… and climate can regulate the dynamics of nitrogen (N) loss from forest watersheds. I address three major gaps in our understanding of the global N cycle: 1) the role of dissolved organic N (DON) in internal N cycling in low-N ecosystems; 2) The influence of atmospheric pollution on DON …
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Natural abundance of ¹⁵N as a tool for assessing patterns of nitrogen loss from forest ecosystems
… isotopes provide an integrated measure of the nitrogen cycling history of a site. Among ecosystems with contrasting nitrate loss patterns, the [delta]15 N of soil and plant material should be higher at sites with higher nitrate losses. An underlying assumption in natural abundance isotope …
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The effect of processing method of broiler litter on pasteurization, nitrogen loss and nitrogen utilization by sheep
… for 30 min. or longer. Moisture and uric acid nitrogen were lowered (P < .01) for dry heat and the PFA processes. Autoclaving and PFA addition followed by dry heating lowered (P < .01) NPN. Ammonia nitrogen was reduced (P < .01) by all pasteurizing treatments except autoclaving for 10 min. A …
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Arm sweat mineral loss and total body mineral determinations in preadolescent boys
The cutaneous sweat loss of calcium, copper, iron, magnesium, manganese, potassium, sodium and zinc of preadolescent boys on diets containing 30, 60, and 90 g protein and various mineral concentrations were studied. Arm sweat collections were made using the arm bag technique. Mineral and nitrogen …
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A case study of investment in agricultural sustainability: adoption and policy issues for nitrogen pollution control in the Chesapeake Bay drainage
… water quality agencies. In particular, excess nitrogen loadings from agricultural production activities threaten water quality in the Bay. Questions have been raised about how effectively traditional BMPs can control nitrogen loss from crop production. This study examines agricultural nitrogen …
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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. …
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Shelf biogeochemical interactions and feedback processes in the Benguela upwelling system
… The BioEBUS model is used to simulate nitrogen processes under oxic and suboxic conditions in upwelling systems with no option for other cycles. Intermediary nitrogen processes, nitrous oxide production and nitrogen loss mechanisms are studied using this model. Physical and advection …
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Effects of elevated carbon dioxide on Bromus rubens and nutritional consequences for the desert tortoise
… using a common diet component, Bromus rubens. Nitrogen balance was monitored for tortoises fed pelleted diets reflecting the nitrogen levels of Bromus plants grown under elevated and ambient CO2 conditions, with varying potassium levels (3.5% and 1.4% DWB). Nitrogen content in the diet …
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Compartmental Process-based Model for Estimating Ammonia Emission from Stored Scraped Liquid Dairy Manure
… manure characteristics (e.g. total ammoniacal nitrogen concentration, pH). These environmental factors and manure characteristics vary spatially as a result of spatially heterogeneous physical, chemical, and biological properties of manure. Existing process-based models used for estimating …
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Nitrogen Regime Influence on Nutrient and Sediment Surface Runoff During Vegetative Establishment of Bermudagrass
… every five minutes and analyzed for sediment losses, N concentrations in the nitrate and ammonium forms, and phosphorus losses as dissolved reactive P (DRP). Experimental results indicate an ability to curb N losses through surface runoff during the initial weeks of sprig establishment …
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The fate of anthropogenic nitrogen in a redox stratified pond: an isotopic approach
… biogeochemical effects accompanying increased nitrogen pollution. Cape Cod is home to roughly 1,000 ponds and lakes which play an important role in local ecosystems, but the cycling of nitrogen in these waters is not well understood. The goal of this research is to identify the major …
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Time And Rate Of Nitrogen Fertilization Influence Maize Nitrogen Use Efficiency And Soil Enzyme Activity
… and spring) and split applications of differing nitrogen (N) rates for maize (Zea mays L.) on an irrigated Hubbard-Mosford loamy sand complex at Becker, a non-irrigated Normania loam soil at Lamberton, and a non-irrigated Nicollet clay loam soil at Waseca, MN. Fall and spring treatments were …
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Farmer adoption of nitrogen modeling tools: perceived barriers and important factors
Agricultural nitrogen runoff contributes around 45% of nitrogen entering the Chesapeake Bay, significantly affecting its water quality. Despite various efforts, the 2025 water quality goal for the Chesapeake Bay Watershed has not yet been achieved. In-season nitrogen modeling tools (NMTs) help …
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Forest Harvesting Disturbance and Site Preparation Effects on Soil Processes and Vegetation in a Young Pine Plantation
… soil biological activity, which increased nitrogen mineralization in excess of pine demand. When non-crop vegetation was chemically controlled, mineralization rates increased due to increases in surface soil temperatures. With less vegetation on the site, the amount of nitrogen sequestered …
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The effects of forest disturbance on stream stability
… successional forest were less retentive of nitrogen and phosphorus than reference sites. Nitrogen loss from disturbed streams averaged 58.04 mg/m²/storm and from reference streams averaged 16.52 mg/m²/storm. Phosphorus loss from disturbed streams averaged 32.52 mg/m²/storm and from reference …
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Nitrogen metabolism in meatmaster sheep fed brewers grain as a supplementary source of protein
This study aimed to examine how nitrogen metabolism in sheep is affected when brewers’ grains are added to diet as a supplementary protein source. Eight Meatmaster rams (average live weight 30 ± 3.2 kg; approximately 6 months old) were randomly allocated to four iso-energetic and iso-nitrogenous …
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Assessment of perennial bioenergy buffers within a row crop production system
… impacts (e.g. water quality, biodiversity loss, greenhouse gas emissions, and declining soil health). One component of multifunctional landscape design in annual row crop production is the integration of perennial bioenergy crops on marginal lands (buffers, filter strips, shelter belts, …
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