The bog landforms of continental western Canada in relation to climate and permafrost patterns
Abstract
In continental western Canada, discontinuous permafrost is almost always restricted to ombrotrophic peatlands (bogs). Bogs occur mostly as islands or peninsulas in large, often complex fens or are confined to small basins. Permafrost may be present in extensive peat plateaus (or more locally as palsas) and was preceded by a well-developed layer of Sphagnum that served to insulate the peat and lower the pore water temperatures. Air photo interpretation reveals the occurrence of bogs with five types of surface physiography. Concentrated to the south are bogs without internal patterns that have never had permafrost. Dominating the mid-latitudes are bogs with internal lawns and fens with internal lawns (mostly representing former bogs) that had permafrost lenses in the past that have recently degraded. Concentrated in the northwest are peat plateaus without internal lawns or distinct collapse scars, but with permafrost; dominating in the northernmost area are peat plateaus with extensive permafrost and collapse scars. Relationships are apparent between the current - 1[degrees]C isotherm and the southern occurrence of peat plateaus and between the 0[degrees]C isotherm and the southern edge of bogs and fens with internal lawns. We interpret bogs and fens with internal lawns to represent areas where permafrost degradation ismore »
- Authors:
- (Univ. of Alberta, Edmonton, Alberta (Canada))
- (Northern Forestry Centre, Edmonton, Alberta (Canada))
- Publication Date:
- OSTI Identifier:
- 7035157
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Arctic and Alpine Research (Boulder, Colorado); (United States); Journal Volume: 26:1
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 54 ENVIRONMENTAL SCIENCES; CANADA; CLIMATIC CHANGE; SWAMPS; PERMAFROST; THAWING; GEOMORPHOLOGY; PEAT; AQUATIC ECOSYSTEMS; DEVELOPED COUNTRIES; ECOSYSTEMS; ENERGY SOURCES; FOSSIL FUELS; FUELS; GEOLOGY; MATTER; NORTH AMERICA; ORGANIC MATTER; TERRESTRIAL ECOSYSTEMS; WETLANDS; 540220* - Environment, Terrestrial- Chemicals Monitoring & Transport- (1990-)
Citation Formats
Vitt, D.H., Halsey, L.A., and Zoltai, S.C.. The bog landforms of continental western Canada in relation to climate and permafrost patterns. United States: N. p., 1994.
Web. doi:10.2307/1551870.
Vitt, D.H., Halsey, L.A., & Zoltai, S.C.. The bog landforms of continental western Canada in relation to climate and permafrost patterns. United States. doi:10.2307/1551870.
Vitt, D.H., Halsey, L.A., and Zoltai, S.C.. Tue .
"The bog landforms of continental western Canada in relation to climate and permafrost patterns". United States.
doi:10.2307/1551870.
@article{osti_7035157,
title = {The bog landforms of continental western Canada in relation to climate and permafrost patterns},
author = {Vitt, D.H. and Halsey, L.A. and Zoltai, S.C.},
abstractNote = {In continental western Canada, discontinuous permafrost is almost always restricted to ombrotrophic peatlands (bogs). Bogs occur mostly as islands or peninsulas in large, often complex fens or are confined to small basins. Permafrost may be present in extensive peat plateaus (or more locally as palsas) and was preceded by a well-developed layer of Sphagnum that served to insulate the peat and lower the pore water temperatures. Air photo interpretation reveals the occurrence of bogs with five types of surface physiography. Concentrated to the south are bogs without internal patterns that have never had permafrost. Dominating the mid-latitudes are bogs with internal lawns and fens with internal lawns (mostly representing former bogs) that had permafrost lenses in the past that have recently degraded. Concentrated in the northwest are peat plateaus without internal lawns or distinct collapse scars, but with permafrost; dominating in the northernmost area are peat plateaus with extensive permafrost and collapse scars. Relationships are apparent between the current - 1[degrees]C isotherm and the southern occurrence of peat plateaus and between the 0[degrees]C isotherm and the southern edge of bogs and fens with internal lawns. We interpret bogs and fens with internal lawns to represent areas where permafrost degradation is currently occurring at a greater rate than aggradation, seemingly in response to warmer regional climate, although fire frequency may also be of local importance. 54 refs., 21 figs., 2 tabs.},
doi = {10.2307/1551870},
journal = {Arctic and Alpine Research (Boulder, Colorado); (United States)},
number = ,
volume = 26:1,
place = {United States},
year = {Tue Feb 01 00:00:00 EST 1994},
month = {Tue Feb 01 00:00:00 EST 1994}
}
-
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