Regulation of decomposition and methane dynamics across natural, commercially mined, and restored northern peatlands
C02 production. Our work in restored block-cut sites compliments that in vacuum-harvested peatlands undergoing more recent active restoration attempts.
The sites we examined covered a large range of soil C substrate quality, nutrient availability, microbial biomass, and microbial activities, allowing us to draw general conclusions about controls on microbial C02 and CH4 dynamics using stepwise regression analysis among all sites and soil depths. Aerobic and anaerobic decomposition of peat was constrained by organic matter quality, particularly phosphorus (P) and carbon (C) chemistry, and clo
sely linked to the size of the microbial biomass supported by these limiting resources. Methane production was more dominantly controlled by field
moisture content (a proxy for anaerobism), even after 20 days of anaerobic laboratory incubation, and to a lesser extent by C substrate availability. As
methanogens likely represented only a small proportion of the total microbial biomass, there were no links between total microbial biomass and CH4 production. Methane oxidation was controlled by the same factors influencing CH4 production, leading to the conclusion that CH4 oxidation is primarily controlled by substrate (that is, CH4) availability. Although restoring hydrology similar to natural sites may re-establish CH4 dynamics, there is geographic or site-specific variability in the ability to restore peat decomposition dynamics.
- Biological Sciences
- carbon dioxide
- FTTR spectroscopy
- methane oxidation
- microbial biomass
- ISSN: 1432-9840