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Showing 1 to 20 of 20 for “"soil drainage"”.
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The distribution of anaerobic bacteria along a soil drainage catena
… the anaerobic bacteria present in three soil sites located along a drainage catena near Blacksburg, Virginia. An anaerobic cooked meat plus 0.5% glucose medium cultured the largest number of anaerobes from the poorly drained soil. The population of obligate anaerobes ranged from 10⁶/ g …
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Surfaces of weathered minerals associated with soil drainage: A quantitative microscopic evaluation
… viewing of the surfaces of silt and sand sized soil minerals. These surfaces are a record of the weathering history of the grain in a particular pedochemical environment. The objective of this dissertation was to develop SEM techniques for the qualitative evaluation of weathered mineral …
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Historical and contemporary drivers of greenhouse gas emissions from upland soils
… that can feed back on climate change by altering soil greenhouse gas (GHG) emissions. Ponding of soils can temporarily decrease soil O2 concentrations, creating conditions conducive for anaerobic biogeochemical reactions that produce and consume nitrous oxide (N2O) and carbon dioxide (CO2). In …
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Late Mississippian (Chesterian) high-frequency climate change in the Pennington Formation at Pound Gap, KY USA.
… of the Vertisols, resulting from changing soil drainage through time. Using the CIA-K proxy, mean annual precipitation (MAP) estimates range from 519 to 1361 mm/yr. Variations in MAP and quantified soil processes correspond with variation s in soil drainage, resulting from high-frequency …
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Impacts of forest harvesting on the performance of soil-landscape modelling in a radiata pine forest, northern New Zealand
… on the spatial distribution of certain target soil properties and locally significant soil classes in order to implement sustainable and site-specific forest management practices. Soil-landscape modelling has been identified as a potentially useful tool for collecting this information. However, …
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The application of Earth Observation for mapping soil saturation and the extent and distribution of artificial drainage on Irish farms
Artificial drainage is required to make wet soils productive for farming. However, drainage may have unintended environmental consequences, for example, through increased nutrient loss to surface waters or increased flood risk. It can also have implications for greenhouse gas emissions. Accurate …
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Distribution and Soil Characteristics Associated with the Neches River Rose-Mallow (Hibiscus dasycalyx)
… Hibiscus species were used to measure select soil characteristics and habitat variables associated with each of the rose-mallows. <em>H. dasycalyx</em> was concluded to be associated with more fertile soils and slightly more canopy coverage than <em>H. laevis</em> and <em>H. moscheutos</em>. …
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Conservation tillage methods for cabbage production
… mountainous southwest region of the state where soil erosion and soil-moisture deficits are major problems associated with row-crop agriculture. The objectives of this study were to assess the applicability of conservation tillage systems for cabbage production. Four tillage systems (conventional …
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Representation of water table dynamics in a land surface scheme : observations, models, and analyses
… receives the recharge from the overlying soils, and discharges runoff into streams. The dependence of groundwater runoff on the water table depth (WTD), i.e., groundwater rating-curve, is parameterized empirically based on the observations in Illinois. The unconfined aquifer model is …
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Modification of the Field Moisture Balance Water Quality model (FMBWQ) to simulate subsurface drainage and preferential flow
… to add the capability of simulating subsurface drainage and preferential flow to FMBWQ. The modified FMBWQ was calibrated and validated for an agricultural plot in the Iowa State University North East Research Center near Nashua, Iowa (hereafter referred to as the Nashua site). The study has …
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Density, Shell Use and Species Composition of Juvenile Fiddler Crabs (Uca Spp.) at Low and High Impact Salt Marshes on Georgia Barrier Islands
… Fiddler crabs are important in aerating the soil, soil drainage, and decomposition rates. A change in fiddler crab densities and behavior can have an adverse affect to the salt marsh and could lead to the loss of an important ecosystem.
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The Impact of Neighborhood-Based Processes on Demography and a Decline in Species Diversity in a Temperate Deciduous Forest
… forest level, including forest edge, aspect, and soil drainage, but rather corresponded to the distributions of preexisting gaps. Disturbances were more likely to occur adjacent to canopy gaps. This study indicates the importance of multiple-scaled and process-based approaches in studying the …
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Nitrification suppression and spinach growth in alkaline soil
… pyridine], was evaluated on spinach in alkaline soil in 2 field experiments and 1 greenhouse experiment. Parameters measured were soil NH4 -N and NO3 -N, spinach yield, leaf color and leaf P, Fe and Zn. Nitrapyrin was adsorbed onto (NH4)2SO4 crystals then applied in a band at planting in the …
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Incorporating Spatial and Temporal Variation of Watershed Response in a GIS-based Hydrologic Model
… spatially distributed excess rainfall using the Soil Conservation Services curve number method (SCS, 1972); the Uniform Curve Number (UCN) model uses a single "average" CN for the whole watershed, thus generating a uniform excess rainfall; the Phi index model which uses the Phi-index method to …
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An evaluation of soil and water management practices on a lowland soil with poor natural drainage
… Lower Fraser Valley tend to have poor natural soil drainage. Excess moisture, because of a high water table and ponded surface water, restricts the range of crops that can be grown and influences farm management decisions regarding the nature and timing of field operations. When economic …
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Effects of Grower Management Practices and Field Characteristics on Insect Damage to Sweetpotato (Ipomoea batatas (L. Lam.) Roots.
… used by growers, as well as the weeds, soil drainage class, and rainfall amounts in those fields, were related to the insect damage on the sampled roots. Approximately 25% of North Carolina's planted sweetpotato acreage was represented by the project conducted in 2002 and 2003. …
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Ecological site quality, site index, and height growth of white spruce stands in the sub-boreal spruce zone of British Columbia
… glauca (Moench) Voss] height growth, vegetation, soil, foliar nutrient, and stem analysis data were obtained from 102 white spruce-dominated stands across a wide range of sites throughout the Sub-Boreal Spruce (SBS) biogeoclimatic zone of central British Columbia. The data were analyzed using the …
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Herbaceous and woody plant establishment across hydrologic gradients in bottomland reforestation sites
… survival and growth. I also evaluated the use of soil magnetic susceptibility (MS), a proxy for soil drainage (other factors being equal), as an easily measured, quantitative predictor of planted tree survival and growth. Lower values of soil MS result from long-term reducing (or anaerobic) soil …
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Heterogeneous Nitrogen Losses: Cost-Effectiveness Analysis of Changes in Management Across South Dakota
… 2013). Further, the addition of nitrogen to the soil through the use of synthetic fertilizers is a main contributor to nitrous oxide (N<sub>2</sub>0) emissions. Approximately 74% of U.S. N<sub>2</sub>O emissions were from synthetic fertilizer applications according to the EPA (2013). However, …
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GIS-based approach to participatory land suitability analysis for tree plantations
… dry months, (3) rooting conditions (r) including soil drainage and rooting depth, (4) nutrient availability (n) specifically availability of phosphate (P2O5); and (5) terrain (s), particularly the number of rock outcrops. Nevertheless, the local communities still considers the rubber trees as …