Name
Towards improved Canadian greenhouse gas accounting: Evaluating emissions from peat extraction management practices.
Date & Time
Tuesday, May 9, 2023, 10:45 AM - 11:00 AM
Steffy Velosa
Description
Peatlands may be stripped of vegetation and drained to actively extract peat for anthropogenic purposes. This land-use change alters the natural biogeochemical cycling of carbon, shifting the ecosystem from a net carbon sink to a carbon source. Our work aims to evaluate the effect of peat extraction management practices on greenhouse gas (GHG) emissions. Fieldwork was conducted at two actively extracted field sites implementing different management strategies in Rivi�re-du-Loup Quebec, from May to November 2022. Using a closed chamber and trace gas analyzer, we collected data on CO2 and CH4 fluxes from covered (by an impermeable reflective tarp) and uncovered peat stockpiles, as well as on peat fields in 4 phases of extraction: recently harrowed, drying, conditioned, and vacuum harvested. We collected gas samples of varying depths within the stockpiles using sippers and analyzed the GHG concentrations using Gas Chromatography. Preliminary results suggest that uncovered stockpiles emit little CH4, and four times more CO2 than extracted peat fields, with greater fluxes occurring at the top of the piles. Covered stockpiles emit very little through the tarp but store high concentrations of both CH4 (>1,000 ppm) and CO2 (>100,000 ppm). We evaluate the influence of temperature and moisture on emission rates which drive seasonal emission trends. We also identify differences in peat field emissions between the extraction phases, resulting from machine manipulation of the uppermost layer of the field altering surface conditions. Our results will help improve land-use GHG emissions in Canada and guide the peat industry towards more sustainable practices.
Location Name
Cedar
Full Address
Banff Park Lodge Resort Hotel & Conference Centre
201 Lynx St
Banff AB T1L 1K5
Canada
Abstract
Peatlands may be stripped of vegetation and drained to actively extract peat for anthropogenic purposes. This land-use change alters the natural biogeochemical cycling of carbon, shifting the ecosystem from a net carbon sink to a carbon source. Our work aims to evaluate the effect of peat extraction management practices on greenhouse gas (GHG) emissions. Fieldwork was conducted at two actively extracted field sites implementing different management strategies in Rivi�re-du-Loup Quebec, from May to November 2022. Using a closed chamber and trace gas analyzer, we collected data on CO2 and CH4 fluxes from covered (by an impermeable reflective tarp) and uncovered peat stockpiles, as well as on peat fields in 4 phases of extraction: recently harrowed, drying, conditioned, and vacuum harvested. We collected gas samples of varying depths within the stockpiles using sippers and analyzed the GHG concentrations using Gas Chromatography. Preliminary results suggest that uncovered stockpiles emit little CH4, and four times more CO2 than extracted peat fields, with greater fluxes occurring at the top of the piles. Covered stockpiles emit very little through the tarp but store high concentrations of both CH4 (>1,000 ppm) and CO2 (>100,000 ppm). We evaluate the influence of temperature and moisture on emission rates which drive seasonal emission trends. We also identify differences in peat field emissions between the extraction phases, resulting from machine manipulation of the uppermost layer of the field altering surface conditions. Our results will help improve land-use GHG emissions in Canada and guide the peat industry towards more sustainable practices.
Session Type
Breakout Session