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Showing 1 to 20 of 44 for “"soil nitrate"”.
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Nitrate and phosphorus leaching, surface soil nitrate concentrations, and nutrient balances under conservation tillage and cover crops in central Illinois
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-08-01
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Yield and nitrogen uptake of broccoli (Brassica oleracea L. var italica) and soil nitrate status as influenced by rate and timing of nitrogen application
… fertilization on these southern Piedmont soils. The objectives of this study were to amend the current recommended nitrogen rates for broccoli production, and to measure plant N uptake and soil nitrate status throughout the growing season in order to develop an efficient N fertilization …
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Management and assessment of winter cover crop systems for supplying nitrogen to corn in the mid-Atlantic region of the United States
… to corn (Zea mays L.). The presidedress soil nitrate test (PSNT) and the Nitrate Quick Test were utilized to determine their viability for making N fertilizer recommendations in cover cropcorn systems. Soil N concentrations peaked in the majority of cover crop treatments at the corn four …
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Nitrogen dynamics and biological response to dairy manure application
… crop yield, and biologic responses to proxy soil health. In a forced air-flow laboratory incubation, manure injection reduced ammonia volatilization by 87% and 98% in a sandy loam and clay loam soil, respectively. The increased ammoniacal nitrogen recovery resulted in increases of soil …
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Legacy effects of cover crop monocultures and mixtures on soil inorganic nitrogen, total phenolic content, and microbial communities on two organic farms in Illinois
… crops can leave behind legacy effects on their soil environments by influencing soil inorganic nitrogen (N) pools, total phenolic content through the release of secondary compounds, and by altering soil microbial communities. I analyzed soils collected during a two-year field study and aimed to …
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Isotope Investigation of Nitrate in Soils and Agricultural Drain Waters of the Lower Yakima Valley, Washington
Nitrate in the groundwater of the Lower Yakima Valley, Washington has long been known to frequently exceed the EPA maximum contaminant level standard for potable water (10 mg/L), adversely impacting communities with disadvantaged socio-economic status. In this research, nitrogen and oxygen isotopic …
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Do benefits from cover crops vary by species or mixture composition?
… known about how diverse species mixtures affect soil nitrogen cycling and soil microbial activity. An on-farm field study was conducted in 2014 and 2015 to assess the impact of 18 cover crop species on soil nitrate levels, tissue nitrogen accumulation, and soil microbial activity. Cover crops …
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Influence of nitrogen rate on corn grain yield, nitrogen use efficiency, and nitrate leaching on coarse-textured Minnesota soils
… often the limiting nutrient in irrigated sandy soils. Nitrogen poses a threat to water quality in its nitrate form because it is easily leached through the root zone of the corn (Zea Mays L.) crop following rain and irrigation events. Leaching is enhanced in sandy soil conditions because sandy …
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Nitrogen cycling in tall fescue turf with added clippings
… of N uptake varied with time. In both studies, soil nitrate levels remained low until excessive clippings smothered the turf and caused a reduction in N uptake. Soil nitrate concentration tended to decrease with depth for all plots. Soil total Kjeldahl nitrogen (TKN) levels did not differ among …
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Greenhouse gas metabolizing prokaryotes in peatlands
… model peatlands with contrasting features (e.g., nitrate content, mean annual temperature, pH) were assessed. A pH-neutral fen produced CH4 in situ as well as in unsupplemented anoxic microcosms. Supplemental N-Acetylglucosaminestimulated formation of fermentation products and CH4 and lead to …
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Effects of nitrogen and cutting management on root growth and productivity of a Kentucky bluegrass (Poa pratensis L.) and white clover (Trifolium repens L.) pasture
… effects on productivity, root growth and soil nitrate (NO3-) in a Kentucky bluegrass and white clover pasture were examined. Nitrogen was applied annually in two equally split applications at rates of 0, 80 or 160 kg N ha -1. After reaching 12.7 cm, plants were cut to 2.5, 5.1 or 7.6 cm. …
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Towards Sociobiogeochemistry: Critical Perspectives on Anthropogenic Alterations to Soil Nitrogen Chemistry via U.S. Urban and Suburban Development
… component of ecosystem functioning, changes to soil biogeochemistry have significant effects on overall ecosystem health. With cities continuing to grow and develop in extent, the impacts of urbanization and suburbanization on soils are of particular concern. Despite a wide range of natural …
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The source of excess nutrients to Pine Draw, Turnbull National Wildlife Refuge
… excess nitrogen inputs to the hydrosphere. Nitrate contamination is a worldwide environmental problem. The fate of nitrogen in ecosystems is variable based on land type and hydrogeological interactions. Excess nitrogen can be retained in soils, sequestered in stream organisms, denitrified or …
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Mycotoxins Risk in Maize Fields in Relation to Insect and Edaphic Factors in South Dakota
… related to aphid abundance. In the final study, soil nitrate levels were positively related to fumonisin concentrations in both conventional and Bt maize. Also it was observed that field slope had a statistically significant negative relationship with fumonisin concentrations because as elevation …
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Evaluating post-fire woody mulch effects on soil and stream nitrogen
… Woody mulch is commonly applied to mitigate soil erosion and enhance revegetation post-fire, but it also provides a source of labile carbon (C) that may stimulate microbial immobilization and limit N release from soils. The objective of our study was to evaluate whether mulch application …
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Impacts of mountain pine beetle outbreak on biogeochemical cycling in a high elevation whitebark pine ecosystem
… than those under unattacked trees. In response, soil NH4+ concentrations in the organic horizons increased from 15 µg N/g soil under unattacked trees to 33 µg N/g soil under attacked trees. However, there were not significant differences in ammonium (NH4+) concentrations in the mineral soil …
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Impacts of mountain pine beetle outbreak on biogeochemical cycling in a high elevation whitebark pine ecosystem
… than those under unattacked trees. In response, soil NH4+ concentrations in the organic horizons increased from 15 µg N/g soil under unattacked trees to 33 µg N/g soil under attacked trees. However, there were not significant differences in ammonium (NH4+) concentrations in the mineral soil …
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Leaf Traits, Neighbors, and Abiotic Factors: Ways That Context Can Mediate the Impact of Invasive Species on Nitrogen Cycling
… are useful for understanding invasion impacts on soil N cycling, but that trait dissimilarities between invaded and reference communities are most informative. Regarding the in-depth studies of Microstegium, we did not find evidence to suggest that invasion increases net nitrification as other …
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Nitrogen availability and pine seedling growth in organically- amended mine soils
… of reclaimed surface mines. Because topsoils are often unrecoverable, “topsoil substitutes”, made up of overburden materials devoid of N, are often used on reclaimed surfaces. Four replications of seven surface treatments were applied to 12 m² plots of 2:1 sandstone:siltstone material on …
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Irrigation management effects on nitrate leaching and mowing requirements of tall fescue
Irrigation management may influence nitrate leaching under tall fescue (Festuca arundinacea) and also affect its mowing requirements. Two experiments were conducted on tall fescue growing on a Chase silt loam soil near Manhattan, Kansas. Each experiment was arranged in a split-plot design, with …
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