Peatlands play a disproportionate role in the global carbon cycle. However, many peatlands have been ditched to lower the water table and converted into agriculture, which contributes to anthropogenic greenhouse gas emissions. Hydrologic restoration of drained peatlands could offset greenhouse gas emissions from these actions, but field examples that consider various greenhouse gases are still rare. Here, we examined emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) from soils in drained shrub bogs in North Carolina, USA, before and after hydrologic restoration. We used static chamber methods and a before-and-after, control-impact (BACI) experimental design. We found that hydrologic manipulation (akin to restoration) increased water table levels by 65%, even with the impact of two hurricanes before and one after hydrologic manipulation. Increased water table levels led to a 58% decrease in CO2 fluxes, and an increase in CH4 (251%) and N2O fluxes (85%). Water table depth and soil temperature explained 43% of variation in CO2, while water table depth explained 25% and 18% of variation in CH4 and N2O fluxes, respectively. Despite the increases in CH4 and N2O, the higher magnitude of fluxes and large decline in CO2 lead to an overall lowering of greenhouse gas emissions after hydrologic restoration. Our results suggest that raising the water table in this shrub bog peatland decreased overall greenhouse gas emissions, illustrating that hydrologic restoration of peatlands can be a valuable climate mitigation practice.
|Title||Hydrologic restoration decreases greenhouse gas emissions from shrub bog peatlands in southeastern US|
|Authors||Luise Armstrong, Ariane Peralta, Ken Krauss, N. Cormier, Rebecca Moss, Eric Soderholm, Aaron McCall, Christine Pickens, Marcelo Ardon|
|Publication Subtype||Journal Article|
|Record Source||USGS Publications Warehouse|
|USGS Organization||Wetland and Aquatic Research Center|
Ken Krauss, Ph.D.
Ken Krauss, Ph.D.