Nunataks and island biogeography in the Alaska-Canada boundary range
A baseline flora of the nunataks, isolated peaks and ridges protruding above glaciers, is developed for the Juneau Icefield. Nunatak and periglacial sites from adjacent areas in Alaska, northern British Columbia, and the Yukon are included. Key sites are investigated phytosociologically and biogeogr...
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ftunivgeorgia:oai:athenaeum.libs.uga.edu:10724/24357 2023-05-15T15:02:06+02:00 Nunataks and island biogeography in the Alaska-Canada boundary range an investigation of the flora and its implications for climate change Bass, Polly 2007-12 http://hdl.handle.net/10724/24357 http://purl.galileo.usg.edu/uga_etd/bass_polly_200712_phd eng eng uga bass_polly_200712_phd http://purl.galileo.usg.edu/uga_etd/bass_polly_200712_phd http://hdl.handle.net/10724/24357 public Nunatak Island biogeography Phytosociology Floristic richness Juneau Icefield Alaska-Canada Boundary Range Sub-Arctic vegetation Alpine vegetation Temperature change Dissertation 2007 ftunivgeorgia 2020-09-23T12:12:59Z A baseline flora of the nunataks, isolated peaks and ridges protruding above glaciers, is developed for the Juneau Icefield. Nunatak and periglacial sites from adjacent areas in Alaska, northern British Columbia, and the Yukon are included. Key sites are investigated phytosociologically and biogeographically. Species richness is considered in relation to winter low temperature, dominant aspect of the study sites, growing-season length, latitude, elevation, the distance of the sites from the continuously vegetated mainland, and the surface area of the study sites. The nunatak habitats are tested against the tenets of the theory of island biogeography. Though difficult in the time frame of the study (approximately seven years) to draw conclusions on extinction and immigration rates, it is possible to identify species not observed in previous investigations. It is also possible to observe the relationship between richness and nunatak surface area, and richness and the distance of a given nunatak from the continuously vegetated mainland. Surface area of the sites is the variable most correlated with 2 species richness. This finding is in agreement with the theory of island biogeography. Latitude, elevation, and growing-season length are further found to have a strong influence on the richness of the vascular plant assemblages. Species richness has more than doubled from 1948 to 2007, in parallel with a recorded increase in the mean annual temperature of the region over the same time period. The floristic data facilitate monitoring the region for further changes. The geobotany of the northern Alaska-Canada Boundary Range harbors significant information on the past, current and future effects of climate change on sub-Arctic and alpine vegetation. PhD Geography Geography Elgene O. Box Elgene O. Box Fausto O. Sarmiento Vernon G. Meentemeyer Ervan G. Garrison Doctoral or Postdoctoral Thesis Arctic Climate change glaciers Alaska Yukon University of Georgia: Athenaeum@UGA Arctic Boundary Range ENVELOPE(-131.854,-131.854,57.083,57.083) British Columbia ENVELOPE(-125.003,-125.003,54.000,54.000) Canada Juneau Icefield ENVELOPE(-134.254,-134.254,58.916,58.916) Nunatak Island ENVELOPE(-66.964,-66.964,66.467,66.467) Sarmiento ENVELOPE(-68.000,-68.000,-72.000,-72.000) Yukon |
institution |
Open Polar |
collection |
University of Georgia: Athenaeum@UGA |
op_collection_id |
ftunivgeorgia |
language |
English |
topic |
Nunatak Island biogeography Phytosociology Floristic richness Juneau Icefield Alaska-Canada Boundary Range Sub-Arctic vegetation Alpine vegetation Temperature change |
spellingShingle |
Nunatak Island biogeography Phytosociology Floristic richness Juneau Icefield Alaska-Canada Boundary Range Sub-Arctic vegetation Alpine vegetation Temperature change Bass, Polly Nunataks and island biogeography in the Alaska-Canada boundary range |
topic_facet |
Nunatak Island biogeography Phytosociology Floristic richness Juneau Icefield Alaska-Canada Boundary Range Sub-Arctic vegetation Alpine vegetation Temperature change |
description |
A baseline flora of the nunataks, isolated peaks and ridges protruding above glaciers, is developed for the Juneau Icefield. Nunatak and periglacial sites from adjacent areas in Alaska, northern British Columbia, and the Yukon are included. Key sites are investigated phytosociologically and biogeographically. Species richness is considered in relation to winter low temperature, dominant aspect of the study sites, growing-season length, latitude, elevation, the distance of the sites from the continuously vegetated mainland, and the surface area of the study sites. The nunatak habitats are tested against the tenets of the theory of island biogeography. Though difficult in the time frame of the study (approximately seven years) to draw conclusions on extinction and immigration rates, it is possible to identify species not observed in previous investigations. It is also possible to observe the relationship between richness and nunatak surface area, and richness and the distance of a given nunatak from the continuously vegetated mainland. Surface area of the sites is the variable most correlated with 2 species richness. This finding is in agreement with the theory of island biogeography. Latitude, elevation, and growing-season length are further found to have a strong influence on the richness of the vascular plant assemblages. Species richness has more than doubled from 1948 to 2007, in parallel with a recorded increase in the mean annual temperature of the region over the same time period. The floristic data facilitate monitoring the region for further changes. The geobotany of the northern Alaska-Canada Boundary Range harbors significant information on the past, current and future effects of climate change on sub-Arctic and alpine vegetation. PhD Geography Geography Elgene O. Box Elgene O. Box Fausto O. Sarmiento Vernon G. Meentemeyer Ervan G. Garrison |
format |
Doctoral or Postdoctoral Thesis |
author |
Bass, Polly |
author_facet |
Bass, Polly |
author_sort |
Bass, Polly |
title |
Nunataks and island biogeography in the Alaska-Canada boundary range |
title_short |
Nunataks and island biogeography in the Alaska-Canada boundary range |
title_full |
Nunataks and island biogeography in the Alaska-Canada boundary range |
title_fullStr |
Nunataks and island biogeography in the Alaska-Canada boundary range |
title_full_unstemmed |
Nunataks and island biogeography in the Alaska-Canada boundary range |
title_sort |
nunataks and island biogeography in the alaska-canada boundary range |
publisher |
uga |
publishDate |
2007 |
url |
http://hdl.handle.net/10724/24357 http://purl.galileo.usg.edu/uga_etd/bass_polly_200712_phd |
long_lat |
ENVELOPE(-131.854,-131.854,57.083,57.083) ENVELOPE(-125.003,-125.003,54.000,54.000) ENVELOPE(-134.254,-134.254,58.916,58.916) ENVELOPE(-66.964,-66.964,66.467,66.467) ENVELOPE(-68.000,-68.000,-72.000,-72.000) |
geographic |
Arctic Boundary Range British Columbia Canada Juneau Icefield Nunatak Island Sarmiento Yukon |
geographic_facet |
Arctic Boundary Range British Columbia Canada Juneau Icefield Nunatak Island Sarmiento Yukon |
genre |
Arctic Climate change glaciers Alaska Yukon |
genre_facet |
Arctic Climate change glaciers Alaska Yukon |
op_relation |
bass_polly_200712_phd http://purl.galileo.usg.edu/uga_etd/bass_polly_200712_phd http://hdl.handle.net/10724/24357 |
op_rights |
public |
_version_ |
1766334084363059200 |