GEOSCAN Search Results: Fastlink


TitlePermafrost thaw induces short-term increase in vegetation productivity in northwestern Canada
AuthorOgden, E LORCID logo; Cumming, S GORCID logo; Smith, S LORCID logo; Turetsky, M RORCID logo; Baltzer, J LORCID logo
SourceGlobal Change Biology 2023, 2023 p. 1-15, Open Access logo Open Access
Alt SeriesNatural Resources Canada, Contribution Series 20220203
Mediapaper; digital; on-line
File formatpdf
ProvinceNorthwest Territories; Nunavut; Yukon
NTS95; 96; 85C; 85D; 85E; 85F; 85L; 85K; 85M; 85N; 86C; 86D; 86E; 86F; 86L; 86K; 86M; 86N; 87B; 87C; 87F; 87G; 97; 105A; 105H; 105I; 105P; 106A; 106H; 106I; 106P; 107A; 107D; 107E
Lat/Long WENS-140.0000 -115.0000 72.0000 60.0000
Subjectsenvironmental geology; Nature and Environment; Science and Technology; permafrost; permafrost geochemistry; vegetation; climate, arctic; ecosystems
Illustrationslocation maps; tables
ProgramClimate Change Geoscience Permafrost
Released2023 06 19
AbstractOver the past several decades, various trends in vegetation productivity, from increases to decreases, have been observed throughout Arctic-Boreal ecosystems. While some of this variation can be explained by recent climate warming and increased disturbance, very little is known about the impacts of permafrost thaw on productivity across diverse vegetation communities. Active layer thickness data from 135 permafrost monitoring sites along a 10° latitudinal transect of the Northwest Territories, Canada, paired with a Landsat time series of normalized difference vegetation index from 1984 to 2019, were used to quantify the impacts of changing permafrost conditions on vegetation productivity. We found that active layer thickness contributed to the observed variation in vegetation productivity in recent decades in the northwestern Arctic-Boreal, with the highest rates of greening occurring at sites where the near-surface permafrost recently had thawed. However, the greening associated with permafrost thaw was not sustained after prolonged periods of thaw and appeared to diminish after the thaw front extended outside the plants' rooting zone. Highest rates of greening were found at the mid-transect sites, between 62.4° N and 65.2° N, suggesting that more southernly sites may have already surpassed the period of beneficial permafrost thaw, while more northern sites may have yet to reach a level of thaw that supports enhanced vegetation productivity. These results indicate that the response of vegetation productivity to permafrost thaw is highly dependent on the extent of active layer thickening and that increases in productivity may not continue in the coming decades.
Summary(Plain Language Summary, not published)
This paper brings together the Geological Survey of Canada's extensive database on permafrost conditions in the Mackenzie Valley with information on vegetation productivity interpreted from satellite imagery. The analysis of these data facilitated an assessment of the role of changes in permafrost conditions in influencing vegetation productivity. The results indicate that the response of vegetation to permafrost thaw is dependent on the extent of active layer thickening. The results facilitate a better understanding of the impact of climate change on northern ecosystems.

Date modified: