Environmental effects of overland winter access: Research conducted in the Mackenzie Delta Julian Kanigan, INAC Overland Winter Access Workshop Inuvik, April 23-24, 2008

Outline 1.Define overland winter access 2.Short-term & long-term effects on: – Vegetation – Permafrost Ground temperatures Thaw depths Thaw settlement 3.Limitations of previous research in the delta

Overland winter access Winter roads – Packed snow roads – Processed snow roads – Ice roads Seismic lines

Short-term effects (1-4 yrs) 2006 ESRF study of vegetation changes on seismic lines

Short-term effects (1-4 yrs) Inuvik snow road 1974 vegetation thaw depths thaw settlement (Northern Engineering Services Company 1974)

Short-term effects (1-4 yrs) Inuvik snow road 1974 vegetation thaw depths thaw settlement (Northern Engineering Services Company 1974) N

Vegetation: short-term effects – ↓ total living vegetation – no species increased as a result of the disturbance – exposed soil – soil compaction – ponding (Northern Engineering Services 1974, Kemper 2006)

Permafrost: short-term effects Shingle Point 1971 ground temperatures (Kerfoot 1972)

Permafrost: short-term effects ↑ Near surface ground temperatures (Kerfoot 1972) Near surface temperatures up to 2°C higher Deeper temperatures the same

Permafrost: short-term effects Sitidgi Creek 1971 thaw depths thaw settlement (Kerfoot 1972)

Permafrost: short-term effects ↑ Thaw depths (Kerfoot 1972)

Permafrost: short-term effects Thaw settlement Sitidgi Creek – Control sites: high ice content – Disturbed sites: ice content correlated with surface settlement (Kerfoot 1972)

Long-term effects (≥5 yrs) Alaskan studies – Low initial disturbance → no longer visible – Moderate/high initial disturbance → visible green trail → brown trail (Felix et al. 1992, Emers & Jorgenson 1997)

Vegetation – long-term effects, MD ↑ total vascular vegetation cover – ESRF upland tundra, 16.5% increase Vegetation cover change – ESRF upland tundra, Inuvik snow road ↑ shrubs ↓ lichens ↓ mosses (Kerfoot 1972, Hardy and Assoc. 1980, Kemper 2006)

Vegetation: long-term effects Alaska north coast Moist shrub-sedge tundra: – ↓ total vegetation cover – vegetation community replacement ↑ sedge cover, ↓ shrub cover (Felix et al. 1992)

Permafrost – long-term effects, MD Inuvik snow road, ESRF upland tundra Thaw depth Thaw settlement Organic layer depth No statistical difference between disturbed and control sites (Hardy and Assoc. 1980, Kemper 2006)

Permafrost – long-term effects Alaska north coast after 5 yrs ( ) – Moderate/high initial disturbance → increased thaw depths – ↑ thaw depths in moist shrub-sedge tundra areas (Felix et al. 1992)

MD Research limitations Few studies and most > 20 years old Mostly short-term studies (1-5 yrs) Lack of baseline data and disturbance level Qualitative, visual assessment of impacts

Conclusions Short-term (1-4 yrs) effects: – Visual indicators changes to vegetation, soil, ponding – Vegetation ↓total living vegetation – Permafrost ↑ nr. surface ground temperatures, ↑ thaw depths, thaw settlement

Conclusions Long-term (≥5 yrs) effects: – Visual indicators none, green trails, brown trails – Vegetation & Permafrost Variable effects depending on: Terrain type? Initial disturbance intensity? Increased thaw depths & vegetation cover change

Recommendations Continued monitoring of historic sites for change Collection of baseline data, disturbance intensity level, and long-term monitoring at new sites Quantitative measures of disturbance Collect complementary data

Thanks, Questions?