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Dissolved organic matter and lake metabolism. Technical progress report, 1 July 1979-30 June 1980

Description: Progress in research to evaluate the impact of utilization of fossil fuels on surface water is reported. Analyses of regulatory mechanisms of growth and rates of carbon cycling center on evaluation of quantitative control interactions among the microflora of the pelagial zones of several lakes of progressively greater eutrophy, littoral photosynthetic producer-decomposer complex, and allochthonous inorganic-organic influxes and their biotic processing. The underlying thesis is that quantificati… more
Date: January 1, 1980
Creator: Wetzel, R.G.
Partner: UNT Libraries Government Documents Department
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Role of temperate zone forests in the world carbon cycle: problem definition and research needs

Description: The proceedings of a workshop on carbon uptake and losses from temperate zone forests are presented. The goals of the workshop were to analyze existing data on growth and utilization of the temperate zone forest carbon pool and to identify further research needs in relation to the role of temperate forests in the global carbon cycle. Total standing stock and growth recovery transients were examined for most of the temperate region over a period from pre-settlement times to the present, with emp… more
Date: January 1, 1979
Creator: Armentano, T.V. & Hett, J. (eds.)
Partner: UNT Libraries Government Documents Department
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Arctic hydrology and meteorology

Description: During 1990, we have continued our meteorological and hydrologic data collection in support of our process-oriented research. The six years of data collected to data is unique in its scope and continuity in a North Hemisphere Arctic setting. This valuable data base has allowed us to further our understanding of the interconnections and interactions between the atmosphere/hydrosphere/biosphere/lithosphere. The increased understanding of the heat and mass transfer processes has allowed us to incr… more
Date: January 1, 1990
Creator: Kane, D.L.
Partner: UNT Libraries Government Documents Department
open access

Calibration and testing or models of the global carbon cycle

Description: A ten-compartment model of the global biogeochemical cycle of carbon is presented. The two less-abundant isotopes of carbon, /sup 13/C and /sup 14/C, as well as total carbon, are considered. The cycling of carbon in the ocean is represented by two well-mixed compartments and in the world's terrestrial ecosystems by seven compartments, five which are dynamic and two with instantaneous transfer. An internally consistent procedure for calibrating this model against an assumed initial steady state … more
Date: January 1, 1980
Creator: Emanuel, W.R.; Killough, G.G. & Shugart, H.H. Jr.
Partner: UNT Libraries Government Documents Department
open access

Sludge application program at the Savannah River Plant

Description: Since 1980 a research program has been conducted at the Savannah River Plant to evaluate the use of domestic sewage sludge to enhance forest productivity. The objectives of the program have been to determine the cost effectiveness and environmental impact of using sewage sludge as a soil conditioner and slow-release fertilizer. The potential impacts of sludge application on nutrient cycling, organic carbon budgets, forest wildlife, and biomass production have been studied. Soil, soil water, gro… more
Date: January 1, 1985
Creator: Corey, J. C.; Lower, M. W. & Davis, C. E.
Partner: UNT Libraries Government Documents Department
open access

Shelf-sea ecosystems

Description: An analysis of the food chain dynamics of the Oregon, Alaskan, and New York shelves is made with respect to differences in physical forcing of these ecosystems. The world's shelves are 10% of the area of the ocean, yield 99% of the world's fish catch, and may be a major sink in the global CO/sub 2/ budget.
Date: January 1, 1980
Creator: Walsh, J J
Partner: UNT Libraries Government Documents Department
open access

Simulations of the carbon cycle in the oceans

Description: This study includes models of oceanic CO{sub 2} uptake. This perturbation simulation of carbon dioxide uptake gives strong support to estimates of oceanic uptake of fossil CO{sub 2} of order 2 GtC/yr. over the last decade. Carbon and carbon-nitrogen models are considered.
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department
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Role of organic soils in the world carbon cycle: problem definition and research needs

Description: The following goals were addressed in the workshop: review and analysis of available data on carbon in organic soils from the past century to the present; assessment of the probable flux of carbon to and from organic soils in the near future; identification of major data inadequacies which preclude reliable analysis of the principal processes influencing carbon flux in organic soils; and proposal of research initiatives which could improve understanding of organic deposits in relation to the ca… more
Date: January 1, 1979
Creator: Armentano, T.V. (ed.)
Partner: UNT Libraries Government Documents Department
open access

Modeling the role of terrestrial ecosystems in the global carbon cycle

Description: A model for the global biogeochemical cycle of carbon which includes a five-compartment submodel for circulation in terrestrial ecosystems of the world is presented. Although this terrestrial submodel divides carbon into compartments with more functional detail than previous models, the variability in carbon dynamics among ecosystem types and in different climatic zones is not adequately treated. A new model construct which specifically treats this variability by modeling the distribution of ec… more
Date: January 1, 1980
Creator: Emanuel, W. R.; Post, W. M. & Shugart, Jr., H. H.
Partner: UNT Libraries Government Documents Department
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Sources and Sinks of Carbon Dioxide in the Arctic Regions

Description: The data base required to adequately ascertain seasonal source and sink strengths in the arctic regions is difficult to obtain. However, there are now a reasonable quantity of data for this polar region to estimate sources and sinks within the Arctic which may contribute significantly to the annual tropospheric CO/sub 2/ concentration fluctuation. The sea-ice-air and the sea-air interfaces account for most of the contribution to the sources and sinks for carbon dioxide. Although the arctic and … more
Date: January 1, 1982
Creator: Gosink, T. A. & Kelley, J. J.
Partner: UNT Libraries Government Documents Department
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Landfill CH sub 4 : Rates, fates, and role in global carbon cycle

Description: Published estimates for worldwide landfill methane emissions range from 9 to 70 Tg yr{sup {minus}1}. Field and laboratory studies suggest that maximum methane yields from lanfilled refuse are about 0.06 to 0.09 m{sup 3} (dry Kg){sup {minus}1} refuse, depending on moisture content and other variables, such as organic loading, buffering capacity, and nutrients in landfill microevnironments. Methane yields may vary by more than an order of magnitude within a given site. Fates for landfill methane … more
Date: January 1, 1991
Creator: Bogner, J. & Spokas, K.
Partner: UNT Libraries Government Documents Department
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Atmospheric Carbon Dioxide and the Global Carbon Cycle: The Key Uncertainties

Description: The biogeochemical cycling of carbon between its sources and sinks determines the rate of increase in atmospheric CO/sub 2/ concentrations. The observed increase in atmospheric CO/sub 2/ content is less than the estimated release from fossil fuel consumption and deforestation. This discrepancy can be explained by interactions between the atmosphere and other global carbon reservoirs such as the oceans, and the terrestrial biosphere including soils. Undoubtedly, the oceans have been the most imp… more
Date: January 1, 1987
Creator: Peng, T. H.; Post, W. M.; DeAngelis, D. L.; Dale, V. H. & Farrell, M. P.
Partner: UNT Libraries Government Documents Department
open access

American Leadership for the Global Climate Crisis

Description: This paper discusses several key areas where U.S. policy should be reshaped, both domestically and internationally, to ensure we lead the world towards a safe, sustainable future. We should: Establish a price for carbon by adopting an ambitious 2020 emissions reduction target. Make investments and adopt policies to stimulate a green economy. Lead the world toward an effective and equitable global climate agreement Support efforts to stop emissions from deforestation and degradation in developin… more
Date: January 2009
Creator: WWF (Organization)
Partner: UNT Libraries
open access

Ground Penetrating Radar in Hydrogeophysics

Description: To meet the needs of a growing population and to provide us with a higher quality of life, increasing pressures are being placed on our environment through the development of agriculture, industry, and infrastructures. Soil erosion, groundwater depletion, salinization, and pollution have been recognized for decades as major threats to ecosystems and human health. More recently, the progressive substitution of fossil fuels by biofuels for energy production and climate change have been recognized… more
Date: January 15, 2008
Creator: Hubbard, Susan; Lambot, S.; Binley, A.; Slob, E. & Hubbard, S.
Partner: UNT Libraries Government Documents Department
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The active site of ribulose-bisphosphate carboxylase/oxygenase

Description: The active site of ribulose-bisphosphate carboxylase/oxygenase requires interacting domains of adjacent, identical subunits. Most active-site residues are located within the loop regions of an eight-stranded {beta}/{alpha}-barrel which constitutes the larger C-terminal domain; additional key residues are located within a segment of the smaller N-terminal domain which partially covers the mouth of the barrel. Site-directed mutagenesis of the gene encoding the enzyme from Rhodospirillum rubrum ha… more
Date: January 1, 1991
Creator: Hartman, F. C.
Partner: UNT Libraries Government Documents Department
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Utilization, cycling and vertical transport of particulate organic matter in the coastal marine environment

Description: This project was funded as part of the California Basin Study (CaBS), a DOE-funded regional program investigating production, cycling, transport, and fate of organic matter, chemical tracers, and pollutants in the Southern California Bight. The study area, adjacent to Los Angeles, was of programmatic interest due to its heavy concentration of energy-related activities, including offshore oil drilling and natural seeps, shipping, nuclear power facilities, and industrial and municipal ocean waste… more
Date: January 1, 1992
Creator: Landry, M. R.
Partner: UNT Libraries Government Documents Department
open access

Chemistry of organic carbon in soil with relationship to the global carbon cycle

Description: Various ecosystem disturbances alter the balances between production of organic matter and its decomposition and therefore change the amount of carbon in soil. The most severe perturbation is conversion of natural vegetation to cultivated crops. Conversion of natural vegetation to cultivated crops results in a lowered input of slowly decomposing material which causes a reduction in overall carbon levels. Disruption of soil matrix structure by cultivation leads to lowered physical protection of … more
Date: January 1, 1988
Creator: Post, W.M. III
Partner: UNT Libraries Government Documents Department
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Molecular biology in studies of oceanic primary production

Description: Remote sensing and the use of moored in situ instrumentation has greatly improved our ability to measure phytoplankton chlorophyll and photosynthesis on global scales with high temporal resolution. However, the interpretation of these measurements and their significance with respect to the biogeochemical cycling of carbon relies on their relationship with physiological and biochemical processes in phytoplankton. For example, the use of satellite images of surface chlorophyll to estimate primary… more
Date: January 1, 1992
Creator: LaRoche, J.; Falkowski, P.G. (Brookhaven National Lab., Upton, NY (United States)) & Geider, R. (Delaware Univ., Lewes, DE (United States). Coll. of Marine Studies)
Partner: UNT Libraries Government Documents Department
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Origins and fates of DOM along the New England continental margin

Description: We have focused on methods development and completed an initial survey of Dissolved Organic Matter (DOM) concentration and isotopic composition during the 1994 spring bloom on Georges Bank. The methods development phase assures that high quality measurements will be made in years 2 and 3, and emphasizes developing two independent methods for DON determination. The survey work on Georges Bank will be extended in years 2 and 3 to determine seasonal and spatial changes in DOM concentrations and is… more
Date: January 1, 1993
Creator: Fry, B.; Hopkinson, C. (Marine Biological Lab., Woods Hole, MA (United States). Ecosystems Center) & Altabet, M. (Woods Hole Oceanographic Institution, MA (United States))
Partner: UNT Libraries Government Documents Department
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Multiple measurement of the coupling between benthic carbon fluxes and bioturbation activity during the spring bloom''

Description: In accordance with the research plan outlined in our original proposal, we began monitoring indicators of plankton production (Chl-a, cell counts) in surface waters of Long Island Sound from the Port Jefferson / Bridgeport Ferry on Dec. 3, 1992. In contrast to past years no dramatic bloom has occurred to date although a significant pattern of increasing chl-a began during the first week of April. We anticipate that the bloom wig be complete by mid to late April. This has been a particularly col… more
Date: January 1, 1992
Creator: Aller, R.C.; Aller, J.J.; Cochran, J.K. & Lee, C.
Partner: UNT Libraries Government Documents Department
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Measurements of metabolically active inorganic phosphate in plants growing in natural and agronomic settings and under water stress. [Stromal Phosphate]

Description: At high rates of photosynthesis, the conflicting requirements of adenosine triphosphate (ATP) synthesis for phosphate and starch and sucrose synthesis for low phosphate, may limit the overall rate of photosynthesis. This is called feedback limitation of photosynthesis. A nonaqueous fractionation technique was used to measure stromal phosphate levels without contamination from vacuolar phosphate. Under normal conditions the stromal phosphate level was found to be 7mM. Under feedback limited phot… more
Date: January 1, 1988
Creator: Sharkey, T.D.
Partner: UNT Libraries Government Documents Department
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Controls on marine carbon fluxes via phytoplankton-mesoplankton interactions in continental shelf waters

Description: The project is an in-depth evaluation of the phytoplankton [yields] phagotrophic protist trophic link. The principal goals of the first year are to develop methods for the second phase of the Ocean Margins Program: investigations in the field. Our project is focused on: impact of grazing by phagotrophic protists on phytoplankton; impact of grazing by phagotrophic protists on bacterioplankton; taxon-specific growth rates of phytoplankton in situ, as they are affected by phagotrophy rates.
Date: January 1, 1992
Creator: Shapiro, L.; Sherr, B.F. & Sherr, E.B.
Partner: UNT Libraries Government Documents Department
open access

Gulf stream frontal eddy influence on productivity of the southeast U.S. continental shelf

Description: Weekly period meanders and eddies are persistent features of Gulf Stream frontal dynamics from Miami, FL, to Cape Hatteras, NC. Satellite imagery and moored current and temperature records reveal a spatial pattern of preferred regions for growth and decay of frontal disturbances. Growth regions occur off Miami, Cape Canaveral and Cape Fear due to baroclinic instability, and decay occurs in the confines of the Straits of Florida between Miami and Palm Beach, between 30{degrees} and 32{degrees}N … more
Date: January 1, 1991
Creator: Lee, T. M.; Yoder, J. & Atkinson, L.
Partner: UNT Libraries Government Documents Department
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Onset time and strength of oceanic deep convection diagnosed from an ocean large-eddy simulation model

Description: Deep convection has an important role in the large-scale thermohaline circulation, which in turn plays a central part in determining global climate. Manabe and Stouffer`s climate simulations have shown that the thermal and dynamic structure of the oceans have pronounced changes in model climates with increased CO{sub 2}. In their simulations, the addition of low-salinity surface water at high latitudes prevents the ventilation of the deep ocean, thus reducing or in some cases nearly extinguishi… more
Date: January 1, 1995
Creator: Denbo, D. W.
Partner: UNT Libraries Government Documents Department
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