Sökning: "carbon sources"
Visar resultat 1 - 5 av 451 avhandlingar innehållade orden carbon sources.
1. Carbon in Boreal Streams : Isotopic Tracing of Terrestrial Sources
Sammanfattning : The boreal biome comprises vast areas of coniferous forests, dotted with millions of peatlands. Plants harbouring these ecosystems fix CO2 from the atmosphere, which is later incorporated into the vegetation biomass and subsequently buried in soils. LÄS MER
2. Allochthonous and autochthonous carbon sources of lake bacterioplankton
Sammanfattning : Organic substrates for pelagic bacteria are derived from dissolved organic carbon (DOC) in the water column that originates either from primary production from within the lake itself (autochthonous), or import of organic matter from the terrestrial watershed (allochthonous production). This thesis addresses the utilization of allochthonous versus autochthonous carbon (C) sources by lake bacterioplankton. LÄS MER
3. Waterborne Carbon in Northern Streams : Controls on dissolved carbon transport across sub-arctic Scandinavia
Sammanfattning : Waterborne carbon (C) forms an active and significant part of the global C cycle, which is important in theArctic where greater temperature increases and variability are anticipated relative to the rest of the globe withpotential implications for the C cycle. Understanding and quantification of the current processes governing themovement of C by connecting terrestrial and marine systems is necessary to better estimate future changes ofwaterborne C. LÄS MER
4. Factors regulating the origin and magnitude of carbon dioxide emissions from high-latitude lakes
Sammanfattning : Lake ecosystems receive, transmit and process terrestrial carbon and thereby link terrestrial, aquatic and global carbon cycles. Most lakes evade CO2 to the atmosphere, but the annual magnitude of CO2 evasion, as well as sources and mechanisms underpinning CO2 evasion from lakes are still largely unresolved. LÄS MER
5. Northern Permafrost Region Soil Carbon Dynamics since the Last Glacial Maximum : a terrestrial component in the glacial to interglacial carbon cycle
Sammanfattning : At the Last Glacial Maximum (LGM), after ~100,000 years of relatively cold temperatures and progressively lower atmospheric carbon dioxide (CO2) concentrations, CO2 levels reached ~180 ppm, which is less than half of what we see today in a much warmer world (~400 ppm). Although much of this increase since the LGM is due to human-induced emissions, about 100 ppm of this increase can be attributed to natural variations seen over glacial to interglacial cycles. LÄS MER
