The importance of freshwater systems to the net atmospheric exchange of carbon dioxide and methane with a rapidly changing high Arctic watershed (Lake Hazen, Quttinirpaaq National Park, Nunavut, Canada)

A warming climate is rapidly changing the distribution and exchanges of carbon within high Arctic ecosystems. Few data exist, however, which quantify exchange of both carbon dioxide (CO2) and methane (CH4) between the atmosphere and freshwater systems, or estimate freshwater contributions to total catchment exchange of these gases, in the high Arctic. During the summers of 2005 and 2007–2012, we quantified CO2 and CH4 concentrations in, and atmospheric exchange with, common freshwater systems in the high Arctic watershed of Lake Hazen, Nunavut, Canada. We identified four types of biogeochemically distinct freshwater systems in the watershed; however mean CO2 concentrations (21–28 µmol L-1) and atmospheric exchange (-0.013 to +0.046 g C–CO2 m-2 day-1) were similar between these systems. Seasonal flooding of ponds bordering Lake Hazen generated considerable CH4 emissions to the atmosphere (+0.008 g C–CH4 m-2 day-1), while all other freshwater systems were minimal emitters of this gas (<+0.001 g C–CH4 m-2 day-1). When using ecosystem-cover classification mapping and data from previous studies, we found that freshwaters were unimportant contributors to total watershed carbon exchange, in part because they covered less than 10% of total area in the watershed. High Arctic watersheds are experiencing warmer and wetter climates than in the past, which may have implications for moisture availability, landscape cover, and the exchange of CO2 and CH4 of underproductive but expansive polar semidesert ecosystems.

Identifier
Source https://www.polardata.ca/pdcsearch/PDCSearchDOI.jsp?doi_id=12712
Metadata Access http://www.polardata.ca/oai/provider?verb=GetRecord&metadataPrefix=fgdc&identifier=12712_fgdc
Provenance
Creator St. Louis, Vincent; Emmerton, Craig
Publisher Canadian Cryospheric Information Network
Contributor Polar Data Catalogue
Publication Year 2016
Rights Research programs, CCIN, or ArcticNet take no liability for the use or transmission of this data
OpenAccess true
Contact emmerton(at)ualberta.ca; pdc(at)uwaterloo.ca
Representation
Language English
Format Computer file
Discipline Biogeochemistry;Chemistry
Spatial Coverage (-71.600W, 81.800S, -71.300E, 81.860N)
Temporal Coverage Begin 2005-05-01T00:00:00Z
Temporal Coverage End 2012-08-15T00:00:00Z