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Showing 1 to 20 of 32 for “"Hybrid Poplar"”.
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Life cycle analysis of hybrid poplar trees for cellulosic ethanol
… energy and environmental benefits of cultivating hybrid poplars as a biomass crop for cellulosic ethanol. A "Life Cycle Assessment" (LCA) methodology is used to systematically evaluate the hybrid poplar's energy input and output as well as greenhouse gas (GHG) emissions. The system boundary is …
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Direct Transpiration and Naphthalene Uptake Rates for a Hybrid Poplar Based Phytoremediation System
… rates and plant uptake of naphthalene by a hybrid poplar phytoremediation system located in Oneida, Tennessee were determined using hydrologic and groundwater concentration data. Water table recession analysis techniques were employed to determine direct transpiration rates from the …
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Relationships Between Hybrid Poplar Tree Extractives and Ground Water Contamination at a Phytoremediation Site
… Oneida, Tennessee with the planting of over 1000 hybrid poplar trees onsite. Creosote, a mixture of hazardous chemicals composed of 85% polycyclic aromatic hydrocarbons (PAH) had entered the site soil and ground water. After planting, a seasonal ground water testing program began that monitored …
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An investigation of the physiological roles and enzymatic properties of invertases in tobacco and hybrid poplar
… yeast-derived invertases in tobacco and hybrid poplar. Transgenic tobacco expressing the yeast-derived invertases showed reduced height and interference in sink-source metabolism. In addition, some transgenic lines showed significant changes in cellulose and lignin content, providing …
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Transformation of Carbon, Nitrogen and Phosphorus in Deep Row Biosolids Incorporation-Hybrid Poplar Plantation in Coastal Plain Mined Land Reclamation Sites
… biosolids and conventional N fertilization on hybrid poplar biomass dynamics, C, N and P sequestration. The following eight treatments were established to achieve objectives (i) and (iv): 0 (control), 167, 337, 504 kg N ha⁻¹ yr⁻¹ as conventional fertilizer; 213 and 426 Mg ha⁻¹ anaerobically …
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Phytoremediation Mechanisms of a Creosote-Contaminated Site
… study was implemented with the planting of 1,026 hybrid poplar trees and 36 cells of vegetated and unvegetated grass and legume treatments. The hybrid poplar tree phytoremediation system was designed to control infiltration and groundwater flow and enhance subsurface remediation. The grass …
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Characterization of a Creosote-Contaminated Tie Yard Site and the Effects of Phytoremediation
… was selected as the remedial technology and hybrid poplar trees were planted at the site in 1997. A research project was designed to: 1) characterize the site through collection of soil and ground water samples; 2) assess phytoremediation effects of 3 grasses, clover, fescue and rye, in …
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Reducing cell wall recalcitrance in poplar through overexpression of cell wall degrading enzymes
… endoglucanase, TnCelB, was expressed in hybrid poplar. The transgenic event with highest TnCelB expression level had reduced lignin content, cellulose crystallinity, and resultant more digestible cell wall. Post-harvest heat treatment improved saccharification efficiencies n transgenic …
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Effect of bioenergy crops and fast growing trees on hydrology and water quality in the Little Vermilion River Watershed
… <p>The functional components and parameters of hybrid poplar Tristis #1 (<em>Populus balsamifera</em> L. × <em>P.tristis</em> Fisch) and eastern cottonwood (<em>Populus deltoides</em> Bartr.) were determined, and related algorithms improved in ALMANAC and SWAT based on improved simulation of …
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Sequestration and Characterization of Soil Organic Carbon for Shelterbelt Agroforestry Systems in Saskatchewan
… including green ash (Fraxinus pennsylvanica), hybrid poplar (Populus spp.), Manitoba maple (Acer negundo), white spruce (Picea glauca), Scots pine (Pinus sylvestris) and caragana (Caragana arborescens) and the adjacent agricultural fields at 59 sampling sites across the agricultural region of …
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Bioremediation of Trichloroethylene: Analysis of the Plant Gene Response to TCE and Characterization of a Novel TCE-Degrading Endophyte
… transporters are involved in TCE metabolism in poplar. The study found that poplar trees do have a genetic response to TCE and that many putative detoxification genes are differentially regulated. Previous studies demonstrated that transgenic hybrid poplar plants expressing mammalian cytochrome …
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Impact of Phytoremediation System on Groundwater Flow in a Shallow Aquifer System
… through several poorly understood mechanisms. Hybrid poplar trees were planted to contain a creosote contaminant plume at the study-site in Oneida, Tennessee. This research looks at how the trees will affect groundwater flow in the site. This is accomplished with the groundwater modeling …
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Effects of Silvicultural Treatments and Soil Properties on the Establishment and Productivity of Trees Growing on Mine Soils in the Appalachian Coalfields
… ranging from -3.7 to 8.9cm in height compared to hybrid poplar, whose height growth ranged from 22.4cm to 126.6cm. Response to silvicultural treatment was variable by site and species, but weed control in combination with tillage generally resulted in the highest survival. Greatest height growth …
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Evapotranspiration Measurement and Simulation due to Poplar Trees at a Phytoremediation Site
… trench was chosen as the remediation strategy. Hybrid poplar trees (1,036) were planted in 1997 within 0.7 acres. The goals of the phytoremediation system are to prevent migration of the contaminant off the site and clean up the contaminant in-situ. This study is focused on quantifying the rate …
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The Missoula Poplar Project: Utilizing Poplars to Enhance Wastewater Treatment
… 316 dormant, unrooted stem cuttings of two hybrid poplar species, Populus deltoides X Populus trichocarpa and Populus deltoides X Populus nigra, and the native Black Cottonwood, Populus balsamifera ssp. trichocarpa. The effects of effluent fertilization on poplar growth, soil and ground …
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The Missoula Poplar Project: Utilizing Poplars to Enhance Wastewater Treatment
… 316 dormant, unrooted stem cuttings of two hybrid poplar species, Populus deltoides X Populus trichocarpa and Populus deltoides X Populus nigra, and the native Black Cottonwood, Populus balsamifera ssp. trichocarpa. The effects of effluent fertilization on poplar growth, soil and ground …
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Appalachian Surface Mine Reforestation Techniques: Effects of Grading, Cultural Treatments and Species Selection
… diversity and improved survival and growth of hybrid American chestnut (Castanea dentata x Castanea mollissima), compared to conventional seeding. Surface water infiltration was positively correlated with herbaceous ground cover. On older mines, subsoil ripping to alleviate compaction improved …
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Push-pull Tests to Quantify In-situ Naphthalene Phytoremediation Rates
… site and to assess the contribution of hybrid poplar trees to polynuclear aromatic hydrocarbon (PAH) remediation. Well positioning enabled comparison between contaminated and non-contaminated locations, as well as comparisons between locations with and without trees. Comparison of areas …
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