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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Carbon and nitrogen turnover in the humus layer of coniferous forests with emphasis on immobilisation, stabilisation and uptake processes /

Sjöberg, R. Michael, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

Effects of atmospheric CO←2 enrichment on root processes and mycorrhizal functioning in short rotation intensive poplar plantation

Lukac, Martin January 2002 (has links)
No description available.

The carbon cycle over the last 1000 years inferred from inversion of ice core data

Trudinger, Catherine Mary, 1968- January 2000 (has links)
Includes bibliographical references.

The carbon budget of a shallow, tropical aquifer sources, sinks, and processes /

Richmond, Nicole L. January 2003 (has links)
Thesis (M.S.)--Miami University, Dept. of Geology, 2003. / Title from first page of PDF document. Document formatted into pages; contains vii, 127 p. : ill. Includes bibliographical references (p. 108-113).

Particulate organic carbon mobilisation and export from temperate forested uplands

Smith, Joanne Caroline January 2013 (has links)
No description available.

The carbon cycle over the last 1000 years inferred from inversion of ice core data /

Trudinger, Catherine Mary, January 2000 (has links)
Thesis (Ph.D.)--Monash University, 2000. / Includes bibliographical references. Also available as pdf file on the WWW.

A procedure for estimating the carbon budget of terrestrial ecosystems in the former Soviet Union by geographic information system analysis and classification of AVHRR derived Global Vegetation Index /

Gaston, Greg G. January 1993 (has links)
Thesis (Ph. D.)--Oregon State University, 1994. / Typescript (photocopy). Includes bibliographical references. Also available online.

Nucleation and growth studies of crystalline carbon phases at nanoscale

Mani, Radhika C., January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Louisville, 2004. / Department of Chemical Engineering. Vita. "August 2004." Includes bibliographical references (leaves 223-250).

How do rates of carbon metabolism vary over a geological gradient, and how does this contribute to riverine greenhouse gas emissions?

Olde, Louise January 2017 (has links)
Rivers and streams are increasingly recognised as important components in the global carbon cycle, and act as net sources of CO2 and CH4 to the atmosphere. However, the origins and controls over the fate of these greenhouse gases are still poorly constrained. This thesis firstly explores the production of CO2 and CH4 in the sediment of several rivers over a geological gradient (chalk, sand and clay), to investigate the magnitude and controls on production. It was found that, whilst there are some general patterns due to geology, variables such as organic carbon content are much better predictors of production of CO2 and CH4 and these can vary widely within a single reach. The response of production to temperature was found to be very constant across rivers and in both summer and winter, suggesting a uniform increase in production of both CO2 and CH4 with projected future climate change. However, production of CH4 was much more responsive to temperature change than was CO2, meaning a greater proportion of carbon is mineralized as CH4 under warmer conditions and indicating a positive feedback with global warming. In addition, the amount of CO2 and CH4 out-gassed from the rivers to the atmosphere was measured. It was found that the amount out-gassed could not be explained by local sediment respiration alone: CO2 out-gassing was consistently higher (and CH4 consistently lower) than that produced by the riverbed. Instead, CO2 out-gassing was under hydrological control, and was correlated with rainfall. The source of this was ingress from the surrounding catchment, with higher out-gassing during periods of high rainfall. This strong hydrological controls on CO2 emissions were however modulated by biological processes, as lower emissions were measured during the day than night; and the difference could be accounted for by local in-stream GPP.

Regional-scale carbon flux estimation using MODIS imagery / Regional scale carbon flux estimation using Moderate Resolution Imaging Spectroradiometer imagery

Cordova, Vicente D. January 2005 (has links)
The National Aeronautics and Space Agency NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) platform carried by Terra and Aqua satellites, is providing systematic measurements summarized in high quality, consistent and well-calibrated satellite images and datasets ranging from reflectance in the visible and near infrared bands to estimates of leaf area index, vegetation indices and biome productivity. The objective of this research was to relate the spectral responses and derived MODIS products of ecosystems, to biogeochemical processes and trends in their physiological variables. When different sources of data were compared, discrepancies between the MODIS variables and the corresponding ground measurements were evident. Uncertainties in the input variables of MODIS products algorithms, effects of cloud cover at the studied pixel, estimation algorithm, and local variation in land cover type are considered as the cause. A simple "continuous field" model based on a physiologically-driven spectral index using two ocean-color bands of MODIS satellite sensor showed great potential to track seasonally changing photosynthetic light use efficiency and stress-induced reduction in net primary productivity of terrestrial vegetation. The model explained 88% of the variability in Flux tower-based daily Net Primary Productivity. Also a high correlation between midday gross CO2 exchange with both daily and 8-day mean gross CO2 exchange, consistent across all the studied vegetation types, was found. Although it may not be possible to estimate 8-day mean Light Use Efficiency reliably from satellite data, Light Use Efficiency models may still be useful for estimation of midday values of gross CO2 exchange which could then be related to longer term means of CO2 exchange. In addition, the MODIS enhanced vegetation index shows a high potential for estimation of ecosystem gross primary production, using respiration values from MODIS surface temperature, providing truly per-pixel estimates. / Department of Natural Resources and Environmental Management

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