Shrub Densification Heterogeneity in Subarctic Regions: The Relative Influence of Historical and Topographic Variables
Expansion of shrub species is widely reported in northern regions, although its extent varies across the landscape. In subarctic Québec (Canada), where dwarf birch (Betula glandulosa Michx) is the main species responsible for shrub expansion, little is known about the causes and consequences of this...
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Centre d'études nordiques, Université Laval
2015
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Online Access: | https://doi.org/10.1080/11956860.2015.1107262 |
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ftbioone:10.1080/11956860.2015.1107262 2024-06-02T08:05:53+00:00 Shrub Densification Heterogeneity in Subarctic Regions: The Relative Influence of Historical and Topographic Variables Pascale Ropars Esther Lévesque Stéphane Boudreau Pascale Ropars Esther Lévesque Stéphane Boudreau world 2015-01-01 text/HTML https://doi.org/10.1080/11956860.2015.1107262 en eng Centre d'études nordiques, Université Laval doi:10.1080/11956860.2015.1107262 All rights reserved. https://doi.org/10.1080/11956860.2015.1107262 Text 2015 ftbioone https://doi.org/10.1080/11956860.2015.1107262 2024-05-07T00:51:19Z Expansion of shrub species is widely reported in northern regions, although its extent varies across the landscape. In subarctic Québec (Canada), where dwarf birch (Betula glandulosa Michx) is the main species responsible for shrub expansion, little is known about the causes and consequences of this phenomenon. This study aims to identify the drivers of dwarf birch densification heterogeneity at the landscape level and to evaluate its influence on other shrub species. We used model selection with Akaike's information criterion to rank ecologically relevant models including topographic, historical and edaphic variables. The influence of dwarf birch densification was evaluated through regression analysis. We found that the best model explaining the heterogeneity in dwarf birch densification in western Nunavik includes factors related to both historical conditions (initial shrub cover, time elapsed since last wildfire) and topography (type of environment). Among these factors, only the initial shrub cover had a significant positive influence on the shrub densification. Increase in dwarf birch cover was found to negatively influence the cover of other shrub species. However, no relation was found between dwarf birch densification and other shrub species richness, suggesting that the densification did not yet lead to the exclusion of less competitive species. Text Dwarf birch Subarctic Nunavik BioOne Online Journals Canada Nunavik Écoscience 22 2-4 83 95 |
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Open Polar |
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BioOne Online Journals |
op_collection_id |
ftbioone |
language |
English |
description |
Expansion of shrub species is widely reported in northern regions, although its extent varies across the landscape. In subarctic Québec (Canada), where dwarf birch (Betula glandulosa Michx) is the main species responsible for shrub expansion, little is known about the causes and consequences of this phenomenon. This study aims to identify the drivers of dwarf birch densification heterogeneity at the landscape level and to evaluate its influence on other shrub species. We used model selection with Akaike's information criterion to rank ecologically relevant models including topographic, historical and edaphic variables. The influence of dwarf birch densification was evaluated through regression analysis. We found that the best model explaining the heterogeneity in dwarf birch densification in western Nunavik includes factors related to both historical conditions (initial shrub cover, time elapsed since last wildfire) and topography (type of environment). Among these factors, only the initial shrub cover had a significant positive influence on the shrub densification. Increase in dwarf birch cover was found to negatively influence the cover of other shrub species. However, no relation was found between dwarf birch densification and other shrub species richness, suggesting that the densification did not yet lead to the exclusion of less competitive species. |
author2 |
Pascale Ropars Esther Lévesque Stéphane Boudreau |
format |
Text |
author |
Pascale Ropars Esther Lévesque Stéphane Boudreau |
spellingShingle |
Pascale Ropars Esther Lévesque Stéphane Boudreau Shrub Densification Heterogeneity in Subarctic Regions: The Relative Influence of Historical and Topographic Variables |
author_facet |
Pascale Ropars Esther Lévesque Stéphane Boudreau |
author_sort |
Pascale Ropars |
title |
Shrub Densification Heterogeneity in Subarctic Regions: The Relative Influence of Historical and Topographic Variables |
title_short |
Shrub Densification Heterogeneity in Subarctic Regions: The Relative Influence of Historical and Topographic Variables |
title_full |
Shrub Densification Heterogeneity in Subarctic Regions: The Relative Influence of Historical and Topographic Variables |
title_fullStr |
Shrub Densification Heterogeneity in Subarctic Regions: The Relative Influence of Historical and Topographic Variables |
title_full_unstemmed |
Shrub Densification Heterogeneity in Subarctic Regions: The Relative Influence of Historical and Topographic Variables |
title_sort |
shrub densification heterogeneity in subarctic regions: the relative influence of historical and topographic variables |
publisher |
Centre d'études nordiques, Université Laval |
publishDate |
2015 |
url |
https://doi.org/10.1080/11956860.2015.1107262 |
op_coverage |
world |
geographic |
Canada Nunavik |
geographic_facet |
Canada Nunavik |
genre |
Dwarf birch Subarctic Nunavik |
genre_facet |
Dwarf birch Subarctic Nunavik |
op_source |
https://doi.org/10.1080/11956860.2015.1107262 |
op_relation |
doi:10.1080/11956860.2015.1107262 |
op_rights |
All rights reserved. |
op_doi |
https://doi.org/10.1080/11956860.2015.1107262 |
container_title |
Écoscience |
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22 |
container_issue |
2-4 |
container_start_page |
83 |
op_container_end_page |
95 |
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1800750763629084672 |