PARENT SESSION
Poster Session 10: Restoration and Adaptive Management
Tuesday, August 9, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal

Impact of restoration on carbon dioxide exchange in a cutover peatland.

Greenwood, Melissa^*,1, Waddington, James¹, ¹ McMaster University, Hamilton, Ontario, Canada

ABSTRACT- Natural peatlands are important components in the global carbon cycle as they represent a net long-term sink of atmospheric carbon dioxide (CO₂), however, peatland extraction converts these ecosystems to persistent sources of atmospheric CO₂ following abandonment. Peatland restoration techniques have been developed with the aim to restore cutover peatlands to carbon-accumulating ecosystem. This is accomplished by raising the water table and reintroducing Sphagnum peat-forming species. The objective of this study was to examine interannual changes in peatland-atmosphere CO₂ exchange post-restoration at a restored peatland. Peat respiration decreased in the restored site post-restoration, which was partially due to the rewetting. However, the seasonal average peat respiration from both the restored and comparison site were not significantly different from each other, suggesting that climatic variability might be the dominant control for peat respiration at this stage of restoration. Subsequently, rates of gross ecosystem production have increased over the same period due to an emerging vegetative cover, with seasonal mean net ecosystem exchange fluxes for both vascular and non-vascular species displaying significant improved net CO₂ fixation with time post restoration. Light response curves showing the relationship between gross ecosystem production of CO₂ (GEP) and photosynthetically active radiation (PAR) indicate that both the apparent quantum efficiency and the maximum GEP (A_max) increased with time post-restoration. Therefore, as the percent cover of vegetation continues to increase at Bois-des-Bel, these results provide promising evidence that the site has the potential to return to a net sink of atmospheric CO₂.

Key words: restoration, peatland, carbon dioxide