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Showing 1 to 20 of 210 for “"Soil organic matter"”.
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Opto-Electronic Sensing of Soil Organic Matter
Made available in DSpace on 2014-12-14T06:37:11Z (GMT). No. of bitstreams: 1 8009080.pdf: 4545676 bytes, checksum: 42e6f2f424de178d35c741b9d01b44e4 (MD5) Previous issue date: 1979
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Near-infrared reflectance soil organic matter sensor
In-field sensing of soil organic matter content would be desirable to provide a control input for the variation of soil-applied herbicide application rates. Control based on organic matter content could eliminate overapplication on less productive areas within a field, thereby improving …
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Consequences of nutrient enrichment for soil organic matter cycling in grasslands
… enrichment affects global C stocks -- such as soil C. Carbon in soil organic matter (SOM) far outweighs vegetative C in the majority of biomes, especially grasslands. Consequently, either positive or negative changes to grassland soil C sequestration could feed back to influence the global C …
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Soil Organic Matter Dynamics in Cropping Systems of Virginia's Valley Region
Soil organic matter (SOM) is a well known indicator of soil quality due to its direct influence on soil properties such as structure, soil stability, water availability, cation exchange capacity, nutrient cycling, and pH buffering and amelioration. Study sites were selected in the Valley region of …
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Effects Of Calcium Addition On Structure And Bioavailability Of Soil Organic Matter
… a long history of acid rain, which has impacted soil fertility and raised concerns about the sustainability of the forests in the region. To facilitate recovery of these forests, calcium addition, in the form of wollastonite, was evaluated as a remedial tool at Hubbard Brook Experimental Forests …
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Control of Herbicide Sprayers With Soil Organic Matter as an Input (Illinois)
… and drop size. Sprayer travel speed and the organic matter in the soil under the sprayer were the design inputs. Step, impulse and sinusoidal demands on the system were made and the resulting flows observed. A transfer function between bypass pressure and bypass flow was sought.
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Landscape and environmental controls on soil organic matter decomposability in the High Arctic
I employed 90 day-laboratory soil incubations, proximate carbon fraction analysis, diffuse reflectance infra-red Fourier transform spectroscopy (DRIFTS) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy to explore how variability in vegetation and soil moisture across the High …
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Soil organic matter dynamics in a temperate forest influenced by extreme weather events
… on the region with effects on C cycling and soil organic matter (SOM). We investigated the influence of extreme weather events (frost/drought) on the quality and quantity of SOM in a Haplic Podzol under a 140 years old Norway spruce forest in the Fichtelgebirge mountains (Bavaria, German) …
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Using satellite hyperspectral imagery to map soil organic matter, total nitrogen and total phosphorus
Up-to-date and accurate information on soil properties is important for precision farming and environmental management. The spatial information of soil properties allows adjustments of fertilizer applications to be made based on knowledge of local field conditions, thereby maximizing agricultural …
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The Influence of Switchgrass Establishment on Soil Organic Matter Pools in an Agricultural Landscape
… agriculture accelerates the decomposition of soil organic matter, contributing to atmospheric carbon and declining soil fertility. Planting perennial warm season grasses is a useful management alternative to row crop agriculture because these species have been shown to be effective at …
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Plant species effects on soil organic matter turnover and nutrient release in forests and grasslands
… characteristics, the formation and turnover of soil carbon and nitrogen pools, and ecosystem processes such as net N mineralization. My objective was to examine two possible effects of species on soil C and N dynamics; changes in organic matter quality and changes in soil aggregation. For …
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Automatic Control of Chemical Application Rate With Soil Organic Matter and Travel Speed as Inputs (Microprocessor, Digital Control)
… chemical application rate according to the soil organic matter content and sprayer ground speed. Bypass nozzles were used to maintain uniform spray characteristics over a wide range of flow rates. The application rate was controlled by regulating the pressure of the bypass line with a …
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A Continental-Scale Investigation of Factors Controlling the Vulnerability of Soil Organic Matter in Mineral Horizons to Decomposition
Soil organic matter (SOM) is the largest terrestrial pool of organic carbon (C), and potential carbon-climate feedbacks involving SOM decomposition could exacerbate anthropogenic climate change. Despite the importance of SOM in the global C cycle, our understanding of the controls on SOM …
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From litter decomposition to soil organic matter formation: using stable isotopes to determine the fate of carbon and nitrogen
… during photosynthesis into the atmosphere and soil. In the soil, carbon and nitrogen from the litter can be stabilized in soil organic matter pools, which globally represent large pools of both carbon (C) and nitrogen (N). Soil organic matter pools are heterogeneous, the product of different …
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Dynamics and Characterization of Soil Organic Matter on Mine Soils 16 Years after Amendment with Topsoil, Sawdust, and Sewage Sludge
… present state and future prospect of the world's soil resources has prompted scientists and researchers to address the issue of soil quality and sustainable land management. Soil quality research has focused on intensively-managed agricultural and forest soils, but the concept and importance of …
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Coarse Root, Forest Litter, and Soil Organic Matter Contributions to Carbon Sequestration in Loblolly Pine (Pinus taeda) Plantations in East Texas
… quantity of carbon sequestered in vegetation and soils. In East Texas and much of the southern United States, there has been a trend of converting marginal pastureland into loblolly pine (Pinus taeda) plantations. This afforestation, like all other land use conversions, leads to a redistribution …
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Development of a Machine Learning Algorithm for the Estimation of Soil Organic Matter from the Integration of UAV and In-Ground Soil Sensor
Biotic wastes and living soil organisms comprise an organic substance of soil known as soil organic matter (SOM). Many agricultural soils are severely depleted in this essential nutrient because of synthetic fertilizers and pesticides over the years. Soil fertility and production can only be better …
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