Paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, Arctic Coastal Plain of Alaska
The dominant landscape process on the Arctic Coastal Plain of northern Alaska is the formation and drainage of thaw lakes. Lakes and drained thaw lake basins account for approximately 75% of the modern surface expression of the Barrow Peninsula. The thaw lake cycle usually obliterates lacustrine or...
Published in: | Palaeogeography, Palaeoclimatology, Palaeoecology |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Lawrence Livermore National Laboratory
2005
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Online Access: | https://doi.org/10.1016/j.palaeo.2004.11.025 https://digital.library.unt.edu/ark:/67531/metadc1409940/ |
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ftunivnotexas:info:ark/67531/metadc1409940 2023-05-15T15:03:48+02:00 Paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, Arctic Coastal Plain of Alaska Eisner, W R Bockheim, J G Hinkel, K M Brown, T A Nelson, F E Peterson, K M Jones, B M United States. Department of Energy. 2005-01-02 page(s) pp. 187-204 Text https://doi.org/10.1016/j.palaeo.2004.11.025 https://digital.library.unt.edu/ark:/67531/metadc1409940/ English eng Lawrence Livermore National Laboratory rep-no: UCRL-JRNL-208806 grantno: W-7405-ENG-48 doi:10.1016/j.palaeo.2004.11.025 osti: 15015873 https://digital.library.unt.edu/ark:/67531/metadc1409940/ ark: ark:/67531/metadc1409940 Journal Name: Palaeogeography, Palaeoclimatology, Palaeoecology; Journal Volume: 217; Journal Issue: 3-4; Other Information: Publication date February 25, 2005; PDF-FILE: 48 SIZE: 2.4 MBYTES Plants Drainage Sediments Pollen 01 Coal Lignite And Peat Nutrients Peat Alaska Lakes Tundra Age Estimation Soils Shrubs Climates 54 Environmental Sciences Carbon Permafrost Plant Growth Article 2005 ftunivnotexas https://doi.org/10.1016/j.palaeo.2004.11.025 2019-02-09T23:08:42Z The dominant landscape process on the Arctic Coastal Plain of northern Alaska is the formation and drainage of thaw lakes. Lakes and drained thaw lake basins account for approximately 75% of the modern surface expression of the Barrow Peninsula. The thaw lake cycle usually obliterates lacustrine or peat sediments from previous cycles which could otherwise be used for paleoecological reconstruction of long-term landscape and vegetation changes. Several possible erosional remnants of a former topographic surface that predates the formation of the thaw lakes have been tentatively identified. These remnants are characterized by a higher elevation, a thick organic layer with very high ground ice content in the upper permafrost, and a plant community somewhat atypical of the region. Ten soil cores were collected from one site, and one core was intensively sampled for soil organic carbon content, pollen analysis, and {sup 14}C dating. The lowest level of the organic sediments represents the earliest phase of plant growth and dates to ca. 9000 cal BP. Palynological evidence indicates the presence of mesic shrub tundra (including sedge, birch, willow, and heath vegetation); and microfossil indicators point to wetter eutrophic conditions during this period. Carbon accumulation was rapid due to high net primary productivity in a relatively nutrient-rich environment. These results are interpreted as the local response to ameliorating climate during the early Holocene. The middle Holocene portion of the record contains an unconformity, indicating that between 8200 and 4200 cal BP sediments were eroded from the site, presumably in response to wind activity during a drier period centered around 4500 cal BP. The modern vegetation community of the erosional remnant was established after 4200 cal BP, and peat growth resumed. During the late Holocene, carbon accumulation rates were greatly reduced in response to the combined effects of declining productivity associated with climatic cooling, and increased nutrient stress as paludification and permafrost aggradation sequestered mineral nutrients. Article in Journal/Newspaper Arctic Barrow Ice permafrost Tundra Alaska University of North Texas: UNT Digital Library Arctic Barrow Peninsula ENVELOPE(-66.248,-66.248,63.051,63.051) Palaeogeography, Palaeoclimatology, Palaeoecology 217 3-4 187 204 |
institution |
Open Polar |
collection |
University of North Texas: UNT Digital Library |
op_collection_id |
ftunivnotexas |
language |
English |
topic |
Plants Drainage Sediments Pollen 01 Coal Lignite And Peat Nutrients Peat Alaska Lakes Tundra Age Estimation Soils Shrubs Climates 54 Environmental Sciences Carbon Permafrost Plant Growth |
spellingShingle |
Plants Drainage Sediments Pollen 01 Coal Lignite And Peat Nutrients Peat Alaska Lakes Tundra Age Estimation Soils Shrubs Climates 54 Environmental Sciences Carbon Permafrost Plant Growth Eisner, W R Bockheim, J G Hinkel, K M Brown, T A Nelson, F E Peterson, K M Jones, B M Paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, Arctic Coastal Plain of Alaska |
topic_facet |
Plants Drainage Sediments Pollen 01 Coal Lignite And Peat Nutrients Peat Alaska Lakes Tundra Age Estimation Soils Shrubs Climates 54 Environmental Sciences Carbon Permafrost Plant Growth |
description |
The dominant landscape process on the Arctic Coastal Plain of northern Alaska is the formation and drainage of thaw lakes. Lakes and drained thaw lake basins account for approximately 75% of the modern surface expression of the Barrow Peninsula. The thaw lake cycle usually obliterates lacustrine or peat sediments from previous cycles which could otherwise be used for paleoecological reconstruction of long-term landscape and vegetation changes. Several possible erosional remnants of a former topographic surface that predates the formation of the thaw lakes have been tentatively identified. These remnants are characterized by a higher elevation, a thick organic layer with very high ground ice content in the upper permafrost, and a plant community somewhat atypical of the region. Ten soil cores were collected from one site, and one core was intensively sampled for soil organic carbon content, pollen analysis, and {sup 14}C dating. The lowest level of the organic sediments represents the earliest phase of plant growth and dates to ca. 9000 cal BP. Palynological evidence indicates the presence of mesic shrub tundra (including sedge, birch, willow, and heath vegetation); and microfossil indicators point to wetter eutrophic conditions during this period. Carbon accumulation was rapid due to high net primary productivity in a relatively nutrient-rich environment. These results are interpreted as the local response to ameliorating climate during the early Holocene. The middle Holocene portion of the record contains an unconformity, indicating that between 8200 and 4200 cal BP sediments were eroded from the site, presumably in response to wind activity during a drier period centered around 4500 cal BP. The modern vegetation community of the erosional remnant was established after 4200 cal BP, and peat growth resumed. During the late Holocene, carbon accumulation rates were greatly reduced in response to the combined effects of declining productivity associated with climatic cooling, and increased nutrient stress as paludification and permafrost aggradation sequestered mineral nutrients. |
author2 |
United States. Department of Energy. |
format |
Article in Journal/Newspaper |
author |
Eisner, W R Bockheim, J G Hinkel, K M Brown, T A Nelson, F E Peterson, K M Jones, B M |
author_facet |
Eisner, W R Bockheim, J G Hinkel, K M Brown, T A Nelson, F E Peterson, K M Jones, B M |
author_sort |
Eisner, W R |
title |
Paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, Arctic Coastal Plain of Alaska |
title_short |
Paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, Arctic Coastal Plain of Alaska |
title_full |
Paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, Arctic Coastal Plain of Alaska |
title_fullStr |
Paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, Arctic Coastal Plain of Alaska |
title_full_unstemmed |
Paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, Arctic Coastal Plain of Alaska |
title_sort |
paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, arctic coastal plain of alaska |
publisher |
Lawrence Livermore National Laboratory |
publishDate |
2005 |
url |
https://doi.org/10.1016/j.palaeo.2004.11.025 https://digital.library.unt.edu/ark:/67531/metadc1409940/ |
long_lat |
ENVELOPE(-66.248,-66.248,63.051,63.051) |
geographic |
Arctic Barrow Peninsula |
geographic_facet |
Arctic Barrow Peninsula |
genre |
Arctic Barrow Ice permafrost Tundra Alaska |
genre_facet |
Arctic Barrow Ice permafrost Tundra Alaska |
op_source |
Journal Name: Palaeogeography, Palaeoclimatology, Palaeoecology; Journal Volume: 217; Journal Issue: 3-4; Other Information: Publication date February 25, 2005; PDF-FILE: 48 SIZE: 2.4 MBYTES |
op_relation |
rep-no: UCRL-JRNL-208806 grantno: W-7405-ENG-48 doi:10.1016/j.palaeo.2004.11.025 osti: 15015873 https://digital.library.unt.edu/ark:/67531/metadc1409940/ ark: ark:/67531/metadc1409940 |
op_doi |
https://doi.org/10.1016/j.palaeo.2004.11.025 |
container_title |
Palaeogeography, Palaeoclimatology, Palaeoecology |
container_volume |
217 |
container_issue |
3-4 |
container_start_page |
187 |
op_container_end_page |
204 |
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1766335645454696448 |