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Freshwater wetlands as a biogeochemical archive: Temporal changes in climate and environmental records
Zemanová, Leona ; Novák, Martin (advisor) ; Mihaljevič, Martin (referee) ; Vaňková, Maria (referee)
Worldwide, peatlands cover an area of 4.106 km2 . Plant primary production dominated over organic matter decomposition and enabled organic matter to accumulate during the last 11 000 years. Peatlands represent a reservoir of atmospheric carbon and they are a useful scientific tool for reconstructions of historical atmospheric pollution. The first part of the thesis focuses on peatlands as a dynamic carbon reservoir under predicted climate change that would influence carbon cycling and emissions of greenhouse gases into the atmosphere. Three methodological approaches were used - a mesocosm laboratory incubation, a transplant experiment and in situ gas flux measurements. The laboratory incubation studied the response of peat samples from temperate (Velké Dářko, Czech Republic) and boreal (Stor Åmyran, Sweden) zone to a temperature increase, water table decrease and their combination. Today, the warmer site exhibits ~14 times higher CH4 production potential than the colder site (28 mg m-2 hr-1 at VD, and 2 mg m-2 hr-1 at SA). Both sites respond differently to temperature increases. Changes in methane production were up to 9 fold due to different temperatures. A gradual decrease of water table level from 2 to 14 cm below the peat surface had a much stronger effect, VD exhibited a decrease in methane...
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Freshwater wetlands as a biogeochemical archive: Temporal changes in climate and environmental records
Zemanová, Leona ; Novák, Martin (advisor) ; Mihaljevič, Martin (referee) ; Hojdová, Marie (referee)
Worldwide, peatlands cover an area of 4.106 km2 . Plant primary production dominated over organic matter decomposition and enabled organic matter to accumulate during the last 11 000 years. Peatlands represent a reservoir of atmospheric carbon and they are a useful scientific tool for reconstructions of historical atmospheric pollution. The first part of the thesis focuses on peatlands as a dynamic carbon reservoir under predicted climate change that would influence carbon cycling and emissions of greenhouse gases into the atmosphere. Three methodological approaches were used - a mesocosm laboratory incubation, a transplant experiment and in situ gas flux measurements. The laboratory incubation studied the response of peat samples from temperate (Velké Dářko, Czech Republic) and boreal (Stor Åmyran, Sweden) zone to a temperature increase, water table decrease and their combination. Today, the warmer site exhibits ~14 times higher CH4 production potential than the colder site (28 mg m-2 hr-1 at VD, and 2 mg m-2 hr-1 at SA). Both sites respond differently to temperature increases. Changes in methane production were up to 9 fold due to different temperatures. A gradual decrease of water table level from 2 to 14 cm below the peat surface had a much stronger effect, VD exhibited a decrease in methane...
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