The effect of retrogressive thaw slumps on the delivery of high loads of toxic methylmercury to downstream freshwater systems in the Peel Plateau region, Northwest Territories

Permafrost thaw can considerably increase the transport of materials from land to freshwater systems, as chemical constituents locked up in previously frozen soils become available for mobilization upon thaw. In 2015, preliminary research on the Peel Plateau, showed substantial increases in methylmercury (MeHg; the toxic form of mercury that bioaccumulates in organisms and biomagnifies in food chains) in streams that had retrogressive thaw slumps (RTSs) adjacent to them.

With climate change, RTS features are becoming increasingly prevalent in the western Canadian Arctic. These features have been associated with changes in (non-Hg) streamwater chemistry as far downstream as the Peel River. During the summer of 2016, we followed up on our preliminary 2015 research by exploring how slumping affects streamwater Hg concentrations with increasing distance downstream from slumps, and quantifying seasonal variability in the effect of slumping on streamwater Hg. The Peel Plateau and downstream reaches are used extensively by local communities for traditional hunting and fishing practices.

Samples for mercury and associated water chemistry parameters were collected upstream and downstream of slumps, and from slump headwalls, to determine the effect of slumping on mercury concentrations in this environment.

Metadata Access
Creator Tank, Suzanne
Publisher Canadian Cryospheric Information Network
Contributor Polar Data Catalogue
Publication Year 2017
Rights Research programs, CCIN, or ArcticNet take no liability for the use or transmission of this data
OpenAccess true
Contact suzanne.tank(at); pdc(at)
Language English
Format Computer file
Discipline Biogeochemistry
Spatial Coverage (-135.970W, 67.142S, -135.080E, 67.415N)
Temporal Coverage Begin 2016-07-01T00:00:00Z
Temporal Coverage End 2016-08-26T00:00:00Z