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Climate warming is shifting northern aquatic ecotones
Marie Alibert1, Reinhard Pienitz2, Dermot Antoniades3
1Department of Geography and Centre for Northern Studies (CEN), Université Laval, Pavillon Abitibi-Price, 2405 Rue de La Terrasse, Québec, G1V 0A6, Canada. marie.alibert.1@ulaval.ca.
Scientific Reports
|January 30, 2026
Summary
Arctic warming is causing significant changes in northern ecosystems. Aquatic ecotones are shifting northward in Canada over the past 25 years due to accelerated regional warming.
Area of Science:
- Ecology
- Climate Change Science
- Limnology
Background:
- Northern ecosystems face amplified warming and altered environmental conditions.
- Arctic freshwater ecosystems are sensitive to rising temperatures and terrestrial changes.
- Species distributions are constrained by changing environmental factors, driving range migrations.
Purpose of the Study:
- To examine shifts in aquatic ecotones along a 1400 km transect in Arctic and Subarctic Canada.
- To investigate the impact of accelerated regional warming on these ecosystems over the past 25 years.
Main Methods:
- Analysis of ecological data across a 1400 km transect.
- Monitoring of aquatic ecotone boundaries.
- Assessment of changes over approximately 25 years.
Main Results:
- Observed northward shifts in aquatic ecotones.
- Evidence of ecosystem response to accelerated regional warming.
- Changes linked to warming-induced alterations in terrestrial vegetation and soils.
Conclusions:
- Arctic and Subarctic aquatic ecosystems are responding to amplified warming.
- Northward ecotone shifts indicate significant ecological reorganization.
- Continued warming will likely drive further changes in northern freshwater systems.
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