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Showing 1 to 20 of 89 for “"soil nitrogen"”.
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Assessing the variability of soil nitrogen mineralization
… could be predicted by a laboratory test. Nitrogen mineralization in the field was highest in May and declined during the growing seasons. Patches of high N mineralization appeared and disappeared during the season, areas of high and low mineralization were not found in the same areas month …
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Winter Annual Cover Crops Interseeded into Soybean in Eastern Virginia: Influence on Soil Nitrogen, Corn Yield, and In-Season Soil Nitrogen Tests
… to establish winter annual cover crops (WCC) for nitrogen (N) scavenging. The winter fallow niche after double-crop or full-season soybean (Glycine max L. Merr.) encompasses the majority of acres left fallow. Our objective was to evaluate interseeded WCC N scavenging performance following soybean …
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Dynamics of inorganic soil-nitrogen age in intensively managed landscape
Our interests in reactive nitrogen and the nitrogen cycle have shifted from increasing the efficiency of nitrogen delivery to target crop species to decreasing environmental damage caused by intensive agricultural practices. Enhancing the reactive nitrogen use to increase food production to meet …
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Belowground Contributions of Pea and Canola to Soil Nitrogen Pools and Processes
Nitrogen (N) contained in roots and rhizodeposits represents a significant input of crop residue-N into soil that is often unaccounted, despite its contribution to the total N budget and its influence on soil nutrient cycling. Utilizing 15N-labeling methodologies under controlled conditions, the …
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Soil nitrogen, active carbon, corn, and small grain response to manure injection
… bands rather than spreading it evenly across the soil surface as done with the typical broadcasting method. The reduced exposure of manure to air under injection can lead to greater N retention when compared to broadcasting, but also alters the spatial distribution of manure. This altered spatial …
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Estimating Soil Nitrogen Supply and Fertilizer Needs for Short-Rotation Woody Crops
… (ages 3-6) sweetgum plantations with contrasting soil types, to 1) determine the plant growth and foliar nutrition response to repeated nitrogen (N) fertilizer applications, 2) determine soil N supply, plant N demand, foliar N resorption, and soil and fertilizer uptake efficiencies, and 3) test a …
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Role of Dissolved Organic Nitrogen in the Soil Nitrogen Cycle of Forest Ecosystems
… (DON) has been shown to be a crucial part of the soil N cycle in forest ecosystems. Despite this, information on its dynamics, sources and fate is still lacking. Especially data from (sub)tropical forest ecosystems are scarce. Therefore, this study investigated (i) the magnitude and drivers of DON …
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Soil nitrogen pools, forms, and losses in mature miscanthus x giganteus under nitrogen fertilization treatments
… x giganteus have shown little effect of nitrogen (N) fertilizer on yield production but have shown increased nitrate leaching and nitrous oxide (N2O) emissions. The effect of this crop on soil organic matter, mineralization of N, and available carbon has not been fully determined, …
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Interacting effects of soil nitrogen supply and light availability on understory sapling growth and foliar attributes
… constraint on sapling growth, but limitations in soil nitrogen (N) availability, and the link to foliar photosynthetic capacity, typically receive less consideration in describing stand dynamics. My primary hypothesis is that light and soil N availability have species-specific effects on …
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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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Changes in Soil Nitrogen Following Biosolids Application to Loblolly Pine (Pinus Taeda L.) Forest in the Virginia Piedmont
… of biosolids as an alternative source of Nitrogen (N) is becoming a common silviculture practices on loblolly pine forest. However, little is known about how biosolids type, application rate, and timing affect forest floor and soil N availability in pine plantations. The objectives of this …
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Land-use change effects on soil organic carbon, total soil nitrogen, and soil erosion in a temperate forest and grassland
… several factors that influence the retention of soil organic carbon (SOC) and total soil nitrogen (TSN) including soil texture, climate, slope length and gradient, and current and past land-use. The purpose of this study was to compare by land use the retention of SOC and TSN on sloping …
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Evaluation of Digital PCR (dPCR) for the Quantification of Soil Nitrogen Turnover Bacteria in Wetland Mesocosms in Response to Season, Fertilization, and Plant Species Richness
… However, the removal of pollutants like nitrogen by wetlands is highly variable, likely due to a combination of factors such as plant species-specific assimilation behavior, the effects of plant communities on microbial diversity and function, and variable nitrogen inputs. In this study, …
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An Approach to Using Labile Soil Nitrogen Measurements for Calibration of the Dssat-Century Agroecosystem Model for Site-Specific Nitrogen Fertilizer Management in Illinois, Unites States
… relationships between the modeled variables and soil N fractions as the ISNT. If such relationships can be identified, it should be possible to use site-specific measurements of soil N fractions to better predict crop responses to fertilizer applications. Although it was possible to obtain …
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Optimizing nitrogen fertilization practices under intensive vineyard cover cropping floor management systems
… sometimes resulted in increased competition for soil nitrogen, leading to decreased vine nitrogen status and berry yeast assimilable nitrogen (YAN). The aim of this study was to determine the effects of different nitrogen fertilization methods applied at varying doses and different times, on vine …
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Rivalry for nutrient resources : is there competition below ground between leguminous trees and grasses in a mesic and arid savanna in the Kruger National Park?
… leguminous C₃ trees and C₄ grasses relative to soil nitrogen, phosphorus and water profiles using stable carbon and nitrogen isotope ratios (of the fine roots). The study occurs on a mesic savanna (737 mm MAP) site on sandy-loam soils and an arid savanna (547 mm MAP) site on clay-rich soils in …
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Competition For Above And Below Ground Resources Among Annual Species From The Plant To The Field: Quantification Analysis And Modeling
… through a modeling exercise the effects of soil nitrogen and weather on competitive growth of Abutilon theophrasti M. (velvetleaf) and Zea mays L. (maize). For this purpose a mechanistic individual based model was developed, which estimates light interception, photosynthesis, respiration, …
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