Peat accumulation in high latitude wetlands represents a natural long-term carbon sink, resulting from the cumulative excess of growing season net ecosystem production over non-growing season (NGS) net mineralization in soils. With high latitudes experiencing warming at a faster pace than the global average, especially during the NGS, a major concern is that enhanced mineralization of soil organic carbon will steadily increase CO2 emissions from northern peatlands. In this study, we conducted laboratory incubations with soils from boreal and temperate peatlands across Canada. Peat soils were pretreated for different soil moisture levels, and CO2 production rates were measured at 12 sequential temperatures, covering a range from − 10 to + 35 °C including one freeze–thaw event. On average, the CO2 production rates in the boreal peat samples increased more sharply with temperature than in the temperate peat samples. For same temperature, optimum soil moisture levels for CO2 production were higher in the peat samples from more flooded sites. However, standard reaction kinetics (e.g., Q10 temperature coefficient and Arrhenius equation) failed to account for the apparent lack of temperature dependence of CO2 production rates measured below 0 °C, and a sudden increase after a freezing event. Thus, we caution against using the simple kinetic expressions to represent the CO2 emissions from northern peatlands, especially regarding the long NGS period with multiple soil freeze and thaw events.
Related Resources
The Boreal-Arctic Wetland and Lake Dataset
Resource Date:
2021
Organization
Natural Climate Solutions for Canada
Resource Date:
June
2021
Estimating the Size of the Reclamation and Restoration Economy and Supply Chain in Alberta
Resource Date:
2021
Organization
Impacts of Seismic Line Restoration on CO2, CH4, and Biomass
Resource Date:
2021
Organization
Integration of Multi-scale Remote Sensing Data for Reindeer Lichen Fractional Cover Mapping in Eastern Canada
Resource Date:
December
2021
Plant Functional Trait Approach to Assess the Persistence of Seismic Line Footprint in Boreal Peatlands of Alberta, Canada
Resource Date:
January
2021
Organization
Was this helpful?
|