Kejimkujik National Park, in Nova Scotia, Canada, is a sensitive region for heavy metal contamination, such as mercury, in part due to long-range atmospheric deposition from global and regional industrial regions. The region is remote from industrial centres, but is downwind of major pollution sources in North America and Canada, and historically had numerous gold mining sites. The region has also experienced anthropogenic acidification from sulphate deposition over the 20th century, which has resulted in limnological conditions favourable for mercury (Hg) methylation within Kejimkujik lakes. Kejimkujik is therefore known to be a hotspot for methylmercury (MeHg) bioaccumulation and biomagnification, with the highest mercury concentrations detected within common loon (Gavia immer) populations across Canada and North America. Due to a paucity of long-term atmospheric deposition monitoring in this region, little is known about the response of Kejimkujik lakes to multiple changing global, regional, and local atmospheric mercury and metals sources. Here we use multiple lake sediment cores to reconstruct anthropogenic depositional fluxes of 45 elements, including mercury and heavy metals of concern for the last ~150 years.
Supplemental Information
The Climate Change and Air Pollution (CCAP) program was established in 2016 to identify the severity and extent of adverse impacts of current and future air emissions on aquatic ecosystems to support regulatory actions and policy development. The program includes a number of components, including identifying, monitoring and defining air quality and greenhouse gas (GHG) concerns; improving our understanding of the short- and long-term effects of atmospheric pollutants on the environment; developing a plan to combat climate change; and monitoring and reducing both domestic and transboundary emissions of GHGs. The program is also responsible for identifying and studying emerging issues including multipollutant impacts, major urban sources, and effects of increasing heat on air pollutant formation, among others.
On-going cooperation and support with the Provinces and Territories, international governments and organizations and academia are vital to deliver these priorities to Canadians.