Paleoenvironmental changes at treeline: a 6,500 year long pollen and stable isotope record
Thesis (M.S.) University of Alaska Fairbanks, 2001 Combined pollen, macrofossil and stable-isotope records from two lakes in the sub-alpine zone of the north-central Alaska Range indicate significant changes in vegetation and lake productivity during the past 6̃750 ¹⁴C yrs BP. These changes are asso...
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ftunivalaska:oai:scholarworks.alaska.edu:11122/6899 2023-05-15T13:09:42+02:00 Paleoenvironmental changes at treeline: a 6,500 year long pollen and stable isotope record Rohr, Melanie 2001-05 http://hdl.handle.net/11122/6899 en_US eng http://hdl.handle.net/11122/6899 Thesis 2001 ftunivalaska 2023-02-23T21:36:44Z Thesis (M.S.) University of Alaska Fairbanks, 2001 Combined pollen, macrofossil and stable-isotope records from two lakes in the sub-alpine zone of the north-central Alaska Range indicate significant changes in vegetation and lake productivity during the past 6̃750 ¹⁴C yrs BP. These changes are associated with neoglacial cooling and climate variations during the Little Ice-Age (LIA). Highest spruce densities occurred during a period from 5,000 ¹⁴C yrs BP and 2,500 ¹⁴C yrs BP and coincided with the onset of cooler and moister climate. The shifts in climate, which resulted in increased effective moisture levels in Central Alaska, possibly shifted the competitive balance towards spruce and against tundra taxa. Lake productivity declined as climate cooled. A brief episode of climate amelioration between 1,500 ¹⁴C yrs BP and 800 ¹⁴C yrs was followed by cooking events of the LIA which resulted in decreased spruce densities in the sub-alpine forest-tundra zone and a possible lowering in treeline at higher elevation. Thesis alaska range Tundra Alaska University of Alaska: ScholarWorks@UA Fairbanks |
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Open Polar |
collection |
University of Alaska: ScholarWorks@UA |
op_collection_id |
ftunivalaska |
language |
English |
description |
Thesis (M.S.) University of Alaska Fairbanks, 2001 Combined pollen, macrofossil and stable-isotope records from two lakes in the sub-alpine zone of the north-central Alaska Range indicate significant changes in vegetation and lake productivity during the past 6̃750 ¹⁴C yrs BP. These changes are associated with neoglacial cooling and climate variations during the Little Ice-Age (LIA). Highest spruce densities occurred during a period from 5,000 ¹⁴C yrs BP and 2,500 ¹⁴C yrs BP and coincided with the onset of cooler and moister climate. The shifts in climate, which resulted in increased effective moisture levels in Central Alaska, possibly shifted the competitive balance towards spruce and against tundra taxa. Lake productivity declined as climate cooled. A brief episode of climate amelioration between 1,500 ¹⁴C yrs BP and 800 ¹⁴C yrs was followed by cooking events of the LIA which resulted in decreased spruce densities in the sub-alpine forest-tundra zone and a possible lowering in treeline at higher elevation. |
format |
Thesis |
author |
Rohr, Melanie |
spellingShingle |
Rohr, Melanie Paleoenvironmental changes at treeline: a 6,500 year long pollen and stable isotope record |
author_facet |
Rohr, Melanie |
author_sort |
Rohr, Melanie |
title |
Paleoenvironmental changes at treeline: a 6,500 year long pollen and stable isotope record |
title_short |
Paleoenvironmental changes at treeline: a 6,500 year long pollen and stable isotope record |
title_full |
Paleoenvironmental changes at treeline: a 6,500 year long pollen and stable isotope record |
title_fullStr |
Paleoenvironmental changes at treeline: a 6,500 year long pollen and stable isotope record |
title_full_unstemmed |
Paleoenvironmental changes at treeline: a 6,500 year long pollen and stable isotope record |
title_sort |
paleoenvironmental changes at treeline: a 6,500 year long pollen and stable isotope record |
publishDate |
2001 |
url |
http://hdl.handle.net/11122/6899 |
geographic |
Fairbanks |
geographic_facet |
Fairbanks |
genre |
alaska range Tundra Alaska |
genre_facet |
alaska range Tundra Alaska |
op_relation |
http://hdl.handle.net/11122/6899 |
_version_ |
1766194180719116288 |