Abstract (eng)
Despite covering only 3% of landmass, peatlands, store about a third of total terrestrial carbon (Baird et al., 2013). Droughts, drainage, and land use change accelerates peat degradation and releases greenhouse gases into atmosphere. Peat sensitivity to changing conditions is complex and depends on interactions of environmental controls, such as temperature, organic matter, water level, and nitrogen availability of which the latter two are analyzed in this study.
In this paper, short-term microbial bog peat degradation was studied in a laboratory environment to compare greenhouse gas contribution of two different botanical compositions, i.e. Sphagnum spp. and Pinus mugo, under varying moisture content and fertilizer exposure scenarios.
Carbon dioxide release increased in peat subjected to drought like conditions by 55% in vascular peat and only 2.5% in moss peat suggesting that microbial community and not litter quality might play role in decomposition. Fertilization intensity did not increase carbon dioxide production linearly, however, under heavy nitrogen addition it increased 1.28 times in moss peat and 1.34 times in vascular plant peat. On the other hand, when methane and nitrous oxide production are taken into account, the highest greenhouse gas production in this study took place in heavily fertilized moss peat. Converted greenhouse gas emission to carbon dioxide equivalents showed, that moss peat produced 50% more than pine peat site, suggesting that pristine, moss dominated peatlands are highly sensitive to changes in environmental controls.