Greenhouse gas emission factors from peat extraction, use and after use

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Twelve percent of Canada is covered with peatlands and containing well over 140 Gt C, making peatlands one of Canada's largest biological carbon pools. The loss of C as CO2 ts through peatland land-use change either directly (e.g. peat extraction), conversion to other land uses (e.g. agricultural, tree plantations, land development) or indirectly (e.g. oil sand development, flooding for hydroelectric reservoirs, etc.). Canada has a small, but important extraction peat industry where the peat is primarily used in horticulture. 300 km2 of Canada's estimated 1.2 x 106 km2 of peatlands have been used for peat extraction, having a tiny effect (<2.2 x 106 t CO2 yr-1) on Canada's CO2 emission inventory (> 7 x 108 t CO2 yr-1). However, for this industry potential future CO2 costs through taxes or cap and trade schemes could be up to $10,000,000/yr. The Canadian peat industry has been very proactive in supporting research on developing techniques for the biological restoration peatlands, and our recent research has shown that biological restoration leads to the return of the natural peatland C cycle within a decade of restoration. However, we cannot tell the industry, due to a lack empirical observations and parameters for our peatland models, what the greenhouse gas emissions (GHG) are during the 10 to 30-year peat extraction period, or how much of the extracted peat is lost back to the atmosphere as CO2 during and after the peat is used. Our objectives over the next five years are to conduct multi-year GHG emission measurements on production peatlands and on peat in use and after use to determine the rate changes in emissions; to develop GHG emission factors (EFs) for the extractive, in use, and after-use stages of the peat industry cycle; and parameterized models to simulate the net change in emissions for peatlands that result from peat extraction. This work will enable the industry to delineate its GHG footprint and it is relevant to provincial and federal agencies responsible for reporting national inventories. Downstream emissions are becoming more important in post UNFCC Paris Accord 2015 discussions and to the future GHG reporting as part of future certification schemes.