Limnology and Paleoenvironmental Research Group
Faculty of Environmental and Urban Change
York University, Toronto, ON, Canada
Permafrost Thaw
Permafrost thaw and its impacts on inland waters manifest differently across the North depending on local land characteristics and legacies of past environmental changes. We study lakes as sentinels and agents of permafrost landscape change to better predict the impacts of future climate warming. We maintain long-term ecological research programs at the Scotty Creek Research Station (Dehcho region) and the Tuktoyaktuk Coastlands in the Northwest Territories.
In the Dehcho region (Northwest Territories), "drunken forests" are a sign of thawing permafrost. The conversion of forests into wetlands alters the transport of organic carbon and mercury to lake ecosystems (Photo credit: J. Thienpont)
Ecosystem Changes in Great Lakes Nearshore and Coastal Areas
The Canada-US Great Lakes Water Quality Agreement (GLWQA) affirms the significance of the Laurentian Great Lakes and commits both countries to maintaining and restoring the integrity of the Great Lakes Basin Ecosystem through cooperation. Monitoring of environmental health is critical to the GLWQA, but a lack of historical data hinders understanding of the full scope of historic and emerging environmental challenges. We use paleolimnological approaches to address critical knowledge gaps on the ecological histories of the nearshore and coastal areas of the Great Lakes, and to identify new ecological changes that might be occurring undetected.
McLaughlin Bay, Lake Ontario, Canada. (Photo credit: J Thienpont)
Limnology and Paleoenvironmental History of the “6th Great Lake”
Lake Nipigon is the largest lake located entirely within Ontario, the 13th largest lake in North America, and the 38th largest lake in the world, and the headwaters of Lake Superior. A history of mining, water diversions, dams, and climate change have undoubtedly had an impact on lake water quality, yet very little is known about their cumulative effects and how they influence Lake Nipigon's vulnerability to emerging stressors. We are working with the Biinjitiwaabik Zaaging Anishinaabek and Lakehead University researchers to generate a holistic understanding of environmental challenges in the Lake Nipigon watershed.
Ombabika Bay, the northermost basin of Lake Nipigon.
(Photo credit: J. Korosi)
Legacy Pollution
Contamination of waterways from past industrial activities leaves behind a legacy of environmental degradation that persists long after such activities have ceased. Our understanding of legacy pollution and its implications for aquatic ecosystems is often hampered by a lack of long-term data, including pre-impact or so-called “baseline” data. Through a combination of lake water quality sampling and paleolimnological assessments, we aim to document the impacts of legacy pollution on aquatic ecosystems and unravel the processes that influence ecological recovery.
Giant Mine, a gold mine in Yellowknife, Northwest Territories that operated from 1948-2004. (Photo credit: L. Kimpe)
Cyanobacteria Blooms
Cyanobacteria (a.k.a. blue-green algae) blooms have been increasing in frequency and severity in lakes across the northern hemisphere because of climate change. We seek to enhance understanding of the drivers of cyanobacteria blooms, with a special focus on shallow, nearshore areas that have the potential to act as cyanobacteria “nurseries”. We work closely with communities and lake associations to enhance local capacity for bloom management.
A cyanobacteria bloom on a lake in Ontario, Canada. (Photo credit: R. Gasman)
Arctic Coastal Storm Surges
Low-lying coastal areas of the circumpolar north are at increasing risk of the impacts of saltwater inundation from marine storm surges because of ongoing decreases in sea ice extent, sea-level rise, and increased storminess. We are working to understand the limnological impacts of saltwater inundation on freshwater ecosystems of coastal locations, and to understand the frequency and impact of recent storm surges in a long-term context. To date much of our research on this phenomenon has occurred in the outer Mackenzie Delta of the western Canadian Arctic.
A lake in the outer Mackenzie Delta impacted by a storm surge in 1999, with dead vegetation surrounding the lake. (Photo credit: J. Thienpont)