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The Rapid Assessment (RA) vegetation dynamics data help to synthesize the best available knowledge of vegetation dynamics and quantify the natural range of variability in vegetation composition and structure. Models consist of two components: (1) a comprehensive description and (2) a quantitative, state-and-transition (box) model, created in the public domain software VDDT (Vegetation Dynamics Development Tool; Beukema et al. 2003). RA vegetation models were based on a simple, standardized five-box model that combines three generic succession stages with two canopy cover classes. Each class is specifically defined for individual models. Variations on this standardized model were also developed. Models were developed...
Because of concerns with the growing threat of global climate change from increasing emissions of greenhouse gases, the United States and other countries are implementing, by themselves or in cooperation with one or more other nations, climate change mitigation projects. These projects will reduce greenhouse gas (GHG) emissions or sequester carbon, and will also result in non-GHG benefits (i.e., environmental, economic, and social benefits). Monitoring, evaluating, reporting, and verifying (MERV) guidelines are needed for these projects to accurately determine their net GHG, and other, benefits. Implementation of MERV guidelines is also intended to: (1) increase the reliability of data for estimating GHG benefits;...
Decentralised bioenergy systems are receiving increasing attention due to the potential ability to support local development, create local employment, and contribute to climate change mitigation. These issues, along with other bioenergy sustainability issues, are reviewed through eighteen international case studies with the objective of identifying opportunities and threats to decentralised bioenergy systems. The case studies were selected based on feedstock type, bioenergy type, production capacity, synergistic alliances, ownership structure and physical locations. This variation was used to provide a basis for evaluating opportunities and threats from different contexts. Commercial viability remains the primary...
This study proposes a new use of Data Envelopment Analysis (DEA) to measure the operational, environmental and both-unified efficiency measures of US coal-fired power plants. The power plants produce not only desirable outputs (e.g., electricity) but also undesirable outputs (e.g., CO2 and NOx) as a result of their plant operations. A Range-Adjusted Measure (RAM) is used as an original non-radial DEA model. Then, it is reformulated for handling undesirable (bad) outputs. The proposed use of DEA models measures the environmental and unified performance of power plants under two variable alternatives (with and without CO2 emission control) in order to examine both the influence of US Clean Air Act (CAA) on the acid...
The Swedish programme for geological disposal of spent nuclear fuel is approaching major milestones in the form of permit applications for an encapsulation plant and a deep geologic repository. This paper presents an overview of the bedrock and surface modelling work that comprises a major part of the on-going site characterization in Sweden and that results in syntheses of the sites, called site descriptions. The site description incorporates descriptive models of the site and its regional setting, including the current state of the geosphere and the biosphere as well as natural processes affecting long-term evolution. The site description is intended to serve the needs of both repository engineering with respect...
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The oxidation of carbon monoxide by mildly oxidized and devolatilized coal samples was studied thermogravimetrically. The oxidation was attributed to oxygen chemisorbed on inorganic components of the coals. The reaction of CO with pyrite producing carbonyl sulphide, OCS, accompanied the oxidation. A mechanism for CO oxidation is proposed in which active oxygen chemisorbed on the inorganic components of the coal directly oxidized CO to CO2, and facilitates the chemisorption of CO on the coal as carbonate. A factor, ?? = ( 11 14) [1 - ( Wn Wc)], was derived where Wn is the sample weight loss not attributed to OCS formation, and Wc is the estimated weight of evolved CO2. This quantity is proportional to the fraction...
Categories: Publication; Types: Citation; Tags: Fuel
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Sixteen trace and minor elements that occur in coal are listed among 189 substances identified as 'hazardous air pollutants' (HAPs) in the US Clean Air Act Amendments of 1990. We investigated the occurrence and cleanability of the 16 HAPs in Illinois coals, as a contribution to the discussion about the potential effect of pending environmental regulations on the future use of these coals in power generation. The average ash content of the samples of conventionally cleaned as-shipped coals is about 20% lower than that of standard channel samples. Conventional cleaning reduces the average concentrations of As, Cd, Co, Hg, Mn, Ni, Pb, Sb and Th in the as-shipped coals by more than 20% relative to channel samples. Thus,...
Categories: Publication; Types: Citation; Tags: Fuel
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Processes affecting neutralization of acidic coal mine drainage were evaluated within 'anoxic' limestone drains (ALDs). Influents had pH???3.5 and dissolved oxygen <2 mg/l. Even though effluents were near neutral (pH 6 and alkalinity acidity), two of the four ALDs were failing due to clogging. Mineral-saturation indices indicated the potential for dissolution of calcite and gypsum, and precipitation of Al3+ and Fe3+ compounds. Cleavage mounts of calcite and gypsum that were suspended within the ALDs and later examined microscopically showed dissolution features despite coatings by numerous bacteria, biofilms, and Fe-Al-Si precipitates. In the drain exhibiting the greatest flow reduction, Al-hydroxysulfates had accumulated...
Categories: Publication; Types: Citation; Tags: Fuel
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An arsenic-rich (As = 55 ppm) bituminous feed coal from the Black Warrior Basin, Alabama and its derivative fly ash (As = 230 ppm) were selected for detailed investigation of arsenic residence and chemical forms. Analytical techniques included microbeam analysis, selective extraction, and As K-edge X-ray absorption fine-structure (XAFS) spectroscopy. Most As in the coal is contained in a generation of As-bearing pyrite (FeS2) that formed in response to epigenetic introduction of hydrothermal fluids. XAFS results indicate that approximately 50% of the As in the coal sample occurs as the oxidized As(V) species, possibly the result of incipient oxidation of coal and pyrite prior to our analysis. Combustion of pyrite...
Categories: Publication; Types: Citation; Tags: Fuel
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Wildfire and fuel treatment locations for the USFWS Pacific Southwest Region (California, Nevada, Klamath Basin OR) extracted from the Fire Management Information System (FMIS) on October 23, 2015, for fiscal years 1980-2015.
Revegetation and cattle production are major objectives in the reclamation plan for mine tailings at the Highland Valley Copper mine in Canada. Residual molybdenum (Mo) in the tailings is imbibed by vegetation and forages accumulate up to 400 ppm Mo at the Highmont tailings pond. Grazing studies with cattle determined the feasibility of utilising the site for livestock production and published results are reviewed. Clinical evaluations (1999?2001) revealed signs of lameness, diarrhoea and hair coat depigmentation in cows but they recovered without treatment. Supplement trials (2002 ? 2004) demonstrated the efficacy of copper (Cu) sulphate for the alleviation of clinical disorders. Dietary Mo was rapidly eliminated...
The energy consumption and fossil CO2 emissions from the Canadian vegetable greenhouse industry were assessed using greenhouse statistics from 2002 to 2007. The fossil CO2 emissions were compared to the fossil CO2 emitted during transport of an equal weight of food by truck and by airplane from two horticultural production centers in the southern USA to four locations in Canada. The calculations in this paper for Canadian greenhouse energy use for heating were verified against farm energy use survey data collected from greenhouse operators in 1996. Allowing for extrapolations to 1996 from the 2002 to 2007 period, the survey data were underestimated by 12%. Since the survey data were not corrected for possible household...
The Swedish programme for geological disposal of spent nuclear fuel is approaching major milestones in the form of permit applications for an encapsulation plant and a deep geologic repository. This paper presents an overview of the bedrock and surface modelling work that comprises a major part of the on-going site characterization in Sweden and that results in syntheses of the sites, called site descriptions. The site description incorporates descriptive models of the site and its regional setting, including the current state of the geosphere and the biosphere as well as natural processes affecting long-term evolution. The site description is intended to serve the needs of both repository engineering with respect...
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Mo??ssbauer parameters were obtained for four Illinois Basin shales and their corresponding < 2??m clay fractions from wells drilled through the New Albany Shale Group in Henderson, Tazewell, and Effingham counties in Illinois and Christian County in Kentucky. Off-gas analysis indicated that the Illinois cores were in an area of low gas potential, while the Kentucky core was in an area of moderate-to-good potential. Iron-rich dolomite (ankerite) was found in the Kentucky core but not in the Illinois cores. In the Kentucky core, gas content could be correlated with the ankerite in the bulk sample, the Mo??ssbauer M (2) species in the clay fraction, and a ferrous iron species in the clay fraction. The location of...
Categories: Publication; Types: Citation; Tags: Fuel
In response to the increasing global demand for energy, on exploration and development are expanding into frontier areas of the Arctic, where slow-growing tundra vegetation and the underlying permafrost Soils are Very sensitive to disturbance. The creation of vehicle trails on the tundra from seismic exploration for on has accelerated in the past decade, and the cumulative impact represents a geographic footprint that covers a greater extent of Alaska's North Slope tundra than all other direct human impacts combined. Seismic exploration for on and gas was conducted on the coastal plain of the Arctic National Wildlife Refuge, Alaska, USA, in the winters of 1984 and 1985. This study documents recovery Of vegetation...


map background search result map search result map LANDFIRE Rapid Assessment Reference Condition Model: Black sage Region 8 FMIS Wildfire and Fuel Treatment Locations 1980-2015 LANDFIRE Rapid Assessment Reference Condition Model: Black sage Region 8 FMIS Wildfire and Fuel Treatment Locations 1980-2015