H38 Wetland Carbon Flux Research Project

The goal of this NSERC-CRD grant was to evaluate ecosystem function on three restored well-pads used for in situ oil sands extraction in Alberta. As different restoration techniques were used across the sites, it investigated outcomes among treatments and whether they differ, how ecohydrological and chemical conditions associated with each treatment was related to the outcomes, and whether the structure of the plant community reflected these ecosystem functions. Overall objectives were: (1) to evaluate a range of ecosystem functions across categories and compare well-sites to reference undisturbed peatlands in the region, and (2) to compare this functional evaluation to restoration outcome as determined by vegetation community structure, as outlined by Alberta’s peatland well-site reclamation criteria, to determine links between structure and function in restored peatlands.

The final report of this project found: flooded and dry conditions should be avoided; methods that level well-pad surface to match adjacent peatland are likely to lead to ecosystems within natural function range. Productive plant communities can be established on restored well-pads, with productivity expected to rise if trees establish. Similar decomposition rates to natural systems indicate peat accumulation should resume at restored sites. Return to characteristic peatland plant communities requires longer than 10 years, but most treatments had 50% ore more vegetation cover, indicating a trajectory towards recovery. Complete pad removal without peat decompaction created vegetation community most different from reference sites. Appropriate hydrology and establishment of plant cover in general is more important than presence of particular indicator species. This finding could lead to a simplification of assessment criteria for restored well-pads.