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Showing 1 to 20 of 65 for “"soil solution"”.
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Gross N turnover and soil solution chemistry as influenced by fluctuations of soil water potential and water table in a Podzol and a fen soil
… higher frequency of drying/rewetting cycles of soils in the future can be expected. These changes of the meteorological conditions likely result in an increasing frequent and intensive drought periods in summer, causing irregular and extreme drought stress in forest soils or a drawdown of water …
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Nitrification in a pine bark medium
The influence of nitrification on the “soil” solution of container media has not been documented. The investigation of this influence is justified since the ionic form of N in a soil solution has a significant influence on plant tissue nutrient content and growth. Three genera of woody plants were …
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Nutrient dynamics of the forest floor in an Appalachian oak forest stand following clearcutting and whole-tree removal
… from October, 1979, through October, 1980. Soil solution samples were extracted on a biweekly basis from April, 1980, through March, 1981, and concurrent soil moisture and temperature determinations were made. All samples were collected from the clearcut area and an adjacent uncut area. …
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Nitrogen deposition and nitrification in coniferous forests’
… to plant and microbial demands could lead to soil acidification if nitrified in the soil and leached, causing loss of base cations or mobilisation of phytotoxic aluminium. Nutrient imbalances due to high soil solution NH4/cation ratios or damaged root systems may also occur. The fate of the …
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An analysis of solute transport on a harvested hillslope in the southern Appalachian Mountains
… the understanding about the dynamics of these soil solutes, particularly in response to harvesting of forests. Also, the purported role of riparian buffers, where logging is restricted along stream channels, in retaining soil solutes is not well studied in the steeply sloping terrain of the …
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The impact of harvesting and site preparation on nutrient dynamics, soil erosion and stream water quality in the Virginia Piedmont
… and 4) shear, rake-pile, disc. A combination of soil solution, streamwater and soil sampling and a series of soil incubations, both laboratory and <i>in situ</i> monitored changes in the treatment areas following site preparation. Available nitrogen reserves decreased substantially in the shear, …
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Phosphate Reactivity in Long-Term Manure Amended Soils in the Ridge and Valley of Virginia
… released in overland flow is related to P form, soil solution P concentration and the release rate of P from soil. Models relating soil test P (STP) to water soluble P (WSP) and the degree of P saturation (DPS) to STP are used in Virginia to estimate P loss potential. Typically the reservoir of …
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Streamside Management Zone effectiveness for protecting water quality following forestland application of biosolids
… sewage treatment, are surface applied to forest soils to increase nutrient availability. Retaining streamside management zones (SMZs) can limit nutrient pollution of streams. We delineated 15 m SMZs along three intermittent streams in an 18-year-old Pinus taeda L. plantation. We applied biosolids …
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Phosphorus availability in amended minesoils as measured by forage Growth and soil tests
… for correction of phosphorus deficiencies in minesoils based on the dilute double acid test are often of little value for minesoils. This research was designed to determine which of several soil tests gives the best estimation of plant-available P and to determine ways to increase P availability …
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Effect of Microbial Exopolysaccharides in Soil on Metal Availability to Plants (Copper, Cadmium, Binding)
Many microorganisms in soil produce extracellular polysaccharides. Often these materials are anionic due to acidic subunits and substituents. As such, they are potential binding sites for metallic cations--some that are necessary for plant nutrition, and others that are pollutant metals of …
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Impact of pine plantations on the form and mobility of nitrogen in soils of the eastern escarpment region of South Africa
… has documented enhanced NO₃- concentrations in soil solution and stream water resulting from afforestation. There has been much research in the Northern Hemisphere regarding the qualitative and quantitative causes and consequences of N saturation in forest ecosystems. In order to assess the …
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Sorption of Cadmium, Copper, Lead, and Zinc as influenced by pH, ionic strength and selected soil components
Metals sorption in soils is influenced by several factors, including pH, ionic strength, the presence of ionic composition or organic ligands, total amount of metals, and adsorbent loading. These conditions should be considered when evaluating metal sorption capacity of soil material or when …
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Alfalfa growth on acid soil as influenced by Al, Ca, pH and Mo
Soil acidity is a major cause of low yields of alfalfa (Medicago sativa L.) in the southeastern United States. Two field experiments were conducted on an Ernest silt loam soil (fine—loamy, mixed, mesic Aquic Fragiudult) to determine what conditions are necessary for optimal alfalfa growth in an …
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Effects of nitrogen and calcium on photosynthesis and metabolic activity in Acer saccharum in the Catskill Mountains
… the past 50 years. Acid deposition on these thin soils may deplete the concentration of calcium and other essential ions in the soil solution and mobilize other ions that can be harmful to sugar maple (Acer saccharum) rooting systems. The effects of fertilizers on the metabolism and photosynthesis …
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Biogeochemical Investigations in Old Growth and Disturbed Forest Sites at Mount Kilimanjaro
… study aims to present basic information on soils and different parameters of the water and nutrient cycle in intact as well as disturbed tropical mountain rainforest sites at Mt. Kilimanjaro in order to assess the long term effects of forest dissection on biogeochemical parameters. For this …
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Managing scientific change in agricultural policies: soil productivity, resource conservation and the legitimation of agrobiology
… conditions presiding over conceptual changes in soil sciences in Québec since 1960, and the legitimation of research in agrobiology. At the beginning of the seventies, researchers in soil sciences opted for a physico-chemical interpretation of soil fertility phenomena and for a scientific …
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Fire Effects on Soil and Water Quality in the Sierra Nevada Mountains and Great Basin Ecosystems: Emphasis on Nitrogen
The effects of fire on soil and water chemistry have been an area of intense study in recent years. Prescribed fires are increasing as a fire management tool in the Sierra Nevada Mountains in order to remove ladder fuels and mitigate the threat of catastrophic wildfire. The first two studies in …
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Sorption of lead and arsenic on soil components and effectiveness of phosphates for remediating lead and arsenic contaminated soils
… of the potentially costly threats to water and soil resources as well as serious threats to humans. Clay minerals are potential binding agents for pollutants due to their high cation exchange capacity and large surface area. Laboratory investigations were undertaken to evaluate the effect of Fe …
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Vegetative Potential to Reduce Total Dissolved Solid Nutrient Ions Generated from Reclaimed Mine Lands in Central Appalachia
… were used to compare nutrient ion fluxes in soil solution that contribute to TDS between paired plots. Soil and vegetation properties (used as proxies for evapotranspiration and plant uptake) were characterized at each site and correlated with log ratios of common TDS contributing ions [i.e., …
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The development of analytical methods to elucidate the chemical forms of Cu, Zn, Cd and Pb in soil contaminated by sewage sludge and other effluents.
… the chemical speciation of heavy metals in soils contaminted by sewage sludge and distillery wastes. Chapter one serves as an introduction discussing the various heavy metal species that can occur in soils. The chapter also contains a review of the analytical methods that have already been …
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