Projecting impacts of climate change on reclaimed forest in the mineable oil sands

Transcription

1 Projecting impacts of climate change on reclaimed forest in the mineable oil sands Shifting reclamation targets? Hedvig Nenzén, David Price, Brad Pinno, Elizabeth Campbell, Dominic Cyr, Yan Boulanger, Anthony Taylor Northern Forestry Centre, January 10 th 2018

2 Area currently and potentially disturbed Canada: 3rd largest oil reserves worldwide 2

3 Oil Sands surface mining 3 Alberta Oil Sands Quarterly, summer 2017 Tailings = by-product with high concentrations of sodium, sulfate, chloride, and hydrocarbons (naphthenic acids, benzene) Luna and Naeth 2014

4 Aerial view of CNRL Oil Sand mine Pond Plant Pit 4 Google maps

5 Vegetation: initial and planned after mining 5 CNRL EIA, section 11 Closure and reclamation, Available at ftp://ftp.gov.ab.ca/env/fs/eia/

6 Reclamation areas of equivalent capability remain almost constant 6 CNRL EIA 2002

7 Project objectives Operators are legally required to reclaim to equivalent capability With climate change, are predisturbance ecosystems feasible? Identify a baseline with future vegetation in CNRL in absence of mining 7 Audet et al. 2015, Rooney et al. 2015

8 Operators are legally required to reclaim to equivalent capability With climate change, are predisturbance ecosystems feasible? Identify a baseline with future vegetation in CNRL in absence of mining Oil Sands landscape impact? Identify possible climate-suitable reclamation 8 Project objectives Audet et al. 2015, Rooney et al Today 2100 Climatesuitable reclamation? Current-day reclamation practices? No reclamation?

9 Method: Link two vegetation models 1. Picus: assess how climate and soil conditions affect tree growth and establishment probabilities 2. Landis-II: multi-species succession, dispersal in the entire landscape with natural disturbances 9 Lexer and Hönninger 2001, Scheller and Mladenoff 2004

10 Oil Sands future climate: Temperature Precipitation Climate Moisture Index (CMI, Hogg 1997) = precipitation potential evapotranspiration 3 General Circulation Models (GCM) 3 Representative Concentration Pathways (RCPs) 10

11 Disturbances: Drought Drought is important cause of aspen mortality in Alberta Climate Moisture Index (CMI) = precipitation potential evapotranspiration 11 Hogg et al. 2008, Hogg 1997, Niinemets and Valladares 2006

12 Disturbances: Drought Drought is important cause of aspen mortality in Alberta Climate Moisture Index (CMI) = precipitation potential evapotranspiration Adjusted slope by: = drought tolerance (other species) / drought tolerance (aspen) 12 Hogg et al. 2008, Hogg 1997, Niinemets and Valladares 2006

13 Disturbances: Fire and Harvesting Fire probabilities Canadian Homogeneous Fires Regimes Annual area burnt increases from 0.2% to 1.6% under severe climate change Harvesting Within Alpac (Alberta-Pacific Forest Industries) FMA 2 % / 10 years 13 Boulanger et al. 2014

14 Landis-II vegetation model Species Initial distribution Alberta Vegetation Inventory with most common species % sand and clay -> Water holding capacity and ph in each soil 20 m resolution 20 x 18 km, 1.8 million grid cells Simulate Combinations of disturbances and climate change 14 AOSERP 1979, Digitized by CFS

15 Results final average biomass declines under severe climate change scenarios GCMs produce generally similar projections represent wetland and prairie vegetation? 15

16 Results final average biomass declines under severe climate change scenarios GCMs produce generally similar projections Disturbances produce similar projections 16

17 Results: deciduous forest dominates under severe climate change 17

18 Comparison to National Forest Inventory data in Oil Sands Low-biomass stands not predicted because no wetlands in model High-biomass aspen stands not predicted because too long fire-return interval? 18

19 Results: deciduous forest dominates under severe climate change 19

20 Results: deciduous forest dominates under severe climate change 20

21 Results: deciduous forest dominates under severe climate change 21

22 Conclusions Conifers replaced by deciduous, disturbanceadapted species under climate change Grasses and wetlands? Decline of boreal forest also projected by other models Detailed soils maps, Multiple GCMs, Drought Baseline simulation results can inform reclamation plans Plant drought-tolerant species 22 Rehfeldt et al. 2009, Boulanger et al. 2017, Schneider et al. 2009

23 Next steps: Include Mining and Reclamation Model vegetation growth on disturbed and reclaimed areas Identify possible climatesuitable reclamation Google maps 23

24 Oil sands reclamation practices AEW, 2002 Brad Pinno, at CNRL 24 AEW, 2002 Suncor, tailings pond

25 Oil sands reclamation future land forms 25 CNRL EIA 2002

26 Oil sands reclamation modelling soil substrates NST = Non-Segregated Tailings CNRL EIA 2002 Reclamation substrates are different from natural soils Overburden: Mixed, no root regeneration, different nutrients Tailings: fewer data Use model and experimental data Physiological & biogeochemical vegetation model Past reclamation on tailings 26

27 Next steps: extend to whole Oil Sands region: Landscape-scale projections of vegetation Disturbance and reclamation In-situ mining Combined with climate change impacts Thank you! 27

28 References 28 Alberta Environment and Water Best Management Practices for Conservation of Reclamation Materials in the Mineable Oil Sands Region of Alberta. Prepared by MacKenzie, D. for CEMA. Audet, P. et al Reclamation of boreal forest after oil sands mining : anticipating novel challenges in novel environments. - Can. J. For. Res. 45: Boulanger, Y. et al A refinement of models projecting future Canadian fire regimes using homogeneous fire regime zones. - Can. J. For. Res. 44: Boulanger, Y. et al Climate change impacts on forest landscapes along the Canadian southern boreal forest transition zone. - Landsc. Ecol. 32: Errington, R. C. and Pinno, B. D Early successional plant community dynamics on a reclaimed oil sands mine in comparison with natural boreal forest communities. - Écoscience 22: Government of Alberta Conservation and reclamation information letter guidelines for reclamation to forest vegetation in the Athabasca oil sands region. C and R/IL/99-1. Hogg, E. H Temporal scaling of moisture and the forest-grassland boundary in western Canada. - Agric. For. Meteorol. 84: Hogg, E. H. et al Impacts of a regional drought on the productivity, dieback, and biomass of western Canadian aspen forests. - Can. J. For. Res. 38: Leskiw, L. A Land capability classification for forest ecosystems in the oil sands. Lexer, M. J. and Hönninger, K A modified 3D-patch model for spatially explicit simulation of vegetation composition in heterogeneous landscapes. - For. Ecol. Manage. 144: Luna Wolter, G. L. and Naeth, M. A Dry Mature Fine Tailings as Oil Sands Reclamation Substrates for Three Native Grasses. - J. Environ. Qual. 43: McKenney, D. W. et al Customized spatial climate models for North America. - Bull. Am. Meteorol. Soc. 92: Niinemets, Ü. and Valladares, F Tolerance to shade, drought, and waterlogging of temperate northern hemisphere trees and shrubs. - Ecol. Monogr. 76: Noah, M. et al Tracing biogeochemical and microbial variability over a complete oil sand mining and recultivation process. - Sci. Total Environ. 499: Rehfeldt, G. E. et al North American vegetation model for land-use planning in a changing climate: a solution to large classification problems. - Source Ecol. Appl. Ecol. Appl. 22: Renault, S. et al Germination, growth and gas exchange of selected boreal forest seedling in soil containing oil sand tailings. - Environ. Pollut. 107: Rooney, R. C. et al Megaproject reclamation and climate change. - Nat. Clim. Chang. 5: Rowland, S. M. et al Recreating a Functioning Forest Soil in Reclaimed Oil Sands in Northern Alberta: An Approach for Measuring Success in Ecological Restoration. - J. Environ. Qual. 38: Scheller, R. M. and Mladenoff, D. J A forest growth and biomass module for a landscape simulation model, LANDIS: design, validation, and application. - Ecol. Modell. 180: Schneider, R. R. et al Potential effects of climate change on ecosystem distribution in Alberta. - Can. J. For. Res. 39: Turchenek, L. and Lindsay, J Soils Inventory of the Alberta Oil Sands Environmental Research Program Study Area. AOSERP Report 122. Alberta Environment, Edmonton. Digitized by NoFC.