Influence of permafrost thaw on mercury and heavy metal export in the lower Liard Valley, NWT

Project keywords: Permafrost thaw, mercury

Name of project lead: W. Quinton

Project team/partners: For each collaborator please specify: Team member name, role, organization and contact information
 W. Quinton (Laurier); B. Branfireun (Western Ontario); J. Baltzer (Laurier); J. Kanigan (INAC); S. Kokelj (INAC); Jean-Marie River First Nation; Lidlii Kue First Nation; Dept. of Environment and Natural Resources

Status: In Progress

Location:

Year and month project started: June, 2012.

Anticipated completion year of project? Aug., 2014.

Executive year of project (example, year 1 or 2 or 3…) 2

Brief project description:

Through the analysis of the chemical composition of surface waters, subsurface waters, and peat core samples, the concentrations, mobilization, and speciation of mercury will be characterized. The study site is located at Scotty Creek, NWT – just south of Fort Simpson. This area is underlain by discontinuous permafrost and is characterized by plateaus, bogs, and channel fens. Recent studies have shown that some of the permafrost plateaus in this region have been experiencing rapid degradation due to a loss of permafrost. With a focus on both sites that have experienced anthropogenic disturbance, resulting in a loss of permafrost, and those which have not been directly affected by anthropogenic influences, a prediction will be made as to how the export of mercury and, the more toxic, methylmercury could change as a result of permafrost thaw in the basin. This project will not only form the basis for a Master’s thesis for the student but it will also provide a foundation for future research on mercury/methylmercury export in the basin.

Significance of the results (rationale): / project linkages

This research is aimed at answering community concern about possible water quality impacts of permafrost thaw. This issue has been raised by local First Nations communities in the Decho. This project contributes to understanding the overall ecosystem response to thawing permafrost and specifically the possible biogeochemical implications of thaw and resulting ecosystem change.

Key deliverables and reporting: Link to needs of NWT

1. In 2011 a pilot study was conducted at Scotty Creek to identify possible hotspots of methylmercury concentration and relate the location of the hotspots to the ecosystem processes that give rise to their development. Data analysis is on-going.

  1. In 2012 research will focussed on 2 deliverables: a) relating the spatial distribution of methylmercury concentration to the spatial pattern of permafrost thaw; and b) examining the methylation and mobilisation of mercury over a study season as the active layer develops. For the latter, active layer thaw will be used as a surrogate for permafrost thaw.
  2. In 2013, this project will align with ongoing permafrost thaw studies to determine possible linkages between the spatial patterns and rates of permafrost thaw and hot spots of MeHg. Hg flux through any component of the watershed over the thawed period of the year has not been characterized. The objectives are to 1) gain an understanding of how much MeHg is transported through a defined bog cascade; 2) assess the methylating capacity of fens in comparison to bogs; 3) understand if the size of the bog in comparison to its watershed has consequence on MeHg concentrations or methylation rates. 4) Determine is bogs with high watershed size/bog size ratios MeHg are hotspots on the landscape; 5) understand if thawing permafrost is a potential methylation accelerator.

Engagement, training and capacity building

Guidance on community concerns of methyl mercury contamination is provided by the LKFN and Jean-Marie First Nation. It is also being sought from the Trout Lake First Nation with the Asistance of the Partnership Liaison Officer. We are also collaborating with George Low (AAROM) on addressing community concerns.

Links to WSIPlan and NWT Science Agenda

1.1; 2.1 – informally; 2.1B, C, D, F, G, H, I.

Key project tasks for next year (work plan pieces – research)

See deliverables section for 2013.

Key project tasks for next year (work plan pieces – engagement, training and capacity building)
Hire local LKFN band members, meet with LKFN, Jean-Marie FN and Trout Lake FN band leaders, continue to attempt to raise funds for knowledge mobilisation and application at the local level.

Published Papers None yet.