Global warming is forecast to cause significant thawing of the permafrost that
surrounds lakes and rivers across the Arctic, with potential wide-scale effects on the
water quality and biotic characteristics of these water bodies. The benthic environment is
believed to be especially sensitive to permafrost-induced ecological change, and this has
been the focus of recent field intensive research. Five lakes disturbed and three lakes
undisturbed by retrogressive permafrost thaw slumps were sampled during late summer
of 2006 to assess the potential effects of slumping on benthos. Water quality parameters,
submerged macrophytes, benthic invertebrates, and sediment were collected. A
significant difference (p < 0.05) between disturbed and undisturbed lakes was found for
macrophyte, invertebrates, underwater light attenuation, and some sediment variables.
The results suggest that thaw slumps can affect submerged macrophyte biomass, benthic
invertebrate abundance, and also community structure in upland tundra lakes. Such
differences between undisturbed and disturbed lakes are suggested to be related to
changes in water column transparency, sediment nutrient availability, soil and terrestrial
vegetation loading from the landscape, and changes in slope angle of the littoral zone.
| Identifer | oai:union.ndltd.org:uvic.ca/oai:dspace.library.uvic.ca:1828/1041 |
| Date | 01 August 2008 |
| Creators | Mesquita, Patricia S. |
| Contributors | Wrona, Fred J., Prowse, Terry D. |
| Source Sets | University of Victoria |
| Language | English, English |
| Detected Language | English |
| Type | Thesis |
| Rights | Available to the World Wide Web |
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