Methane emissions from a peatland following restoration

1] Peatland drainage and peat extraction changes natural peatlands from a net carbon sink to that of a large net source due to increased respiration and the removal of carbon dioxide ( CO2) fixing vegetation. Restoration of these altered peatland ecosystems is being applied to reduce these carbon emissions. As peatland restoration is a new and emerging land-use management practice, the purpose of this research was to examine the impact of restoration on the methane ( CH4) component of the carbon cycle at the Bois-des-Bel peatland located near Riviere-du-Loup, Quebec from early May to mid October for several years. The seasonal CH4 fluxes prior to restoration at an extracted ( cutover) and a restored peatland were not significantly different from each other or zero. However, three years postrestoration the seasonal CH4 emissions at the restored site were 4.2 g m(-2) CH4 season(-1), 4.6 times greater than the cutover site. Ponds and ditches at the restored site were seasonal CH4 emission hot spots ( 0.3 and 2.9 g m(-2) CH4 season(-1), respectively); however, emissions from herbaceous vegetation ( 1.0 g m(-2) CH4 season(-1)) were the dominant source of CH4 from the restored peatland due to its large areal extent. CH4 fluxes from the Bois-des-Bel peatland represented 14% of the total CO2-equivalent losses from the site. This study demonstrates the importance of vegetation succession on peatland-atmosphere flux of CH4.