Birch shrub growth in the low Arctic: the relative importance of experimental warming, enhanced nutrient availability, snow depth and caribou exclusion
Deciduous shrub growth has increased across the Arctic simultaneously with recent climate warming trends. The reduction in albedo associated with shrub-induced ‘greening’ of the tundra is predicted to cause significant positive feedbacks to regional warming. Enhanced soil fertility arising from clim...
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ftdoajarticles:oai:doaj.org/article:5ecb58fcd471429696935059710372f6 2023-09-05T13:11:31+02:00 Birch shrub growth in the low Arctic: the relative importance of experimental warming, enhanced nutrient availability, snow depth and caribou exclusion Tara J Zamin Paul Grogan 2012-01-01T00:00:00Z https://doi.org/10.1088/1748-9326/7/3/034027 https://doaj.org/article/5ecb58fcd471429696935059710372f6 EN eng IOP Publishing https://doi.org/10.1088/1748-9326/7/3/034027 https://doaj.org/toc/1748-9326 doi:10.1088/1748-9326/7/3/034027 1748-9326 https://doaj.org/article/5ecb58fcd471429696935059710372f6 Environmental Research Letters, Vol 7, Iss 3, p 034027 (2012) shrub expansion Arctic tundra climate change experimental warming fertilization nutrient limitation Environmental technology. Sanitary engineering TD1-1066 Environmental sciences GE1-350 Science Q Physics QC1-999 article 2012 ftdoajarticles https://doi.org/10.1088/1748-9326/7/3/034027 2023-08-13T00:37:44Z Deciduous shrub growth has increased across the Arctic simultaneously with recent climate warming trends. The reduction in albedo associated with shrub-induced ‘greening’ of the tundra is predicted to cause significant positive feedbacks to regional warming. Enhanced soil fertility arising from climate change is expected to be the primary mechanism driving shrub responses, yet our overall understanding of the relative importance of soil nitrogen (N) and phosphorus (P) availability and the significance of other ecological drivers is constrained by experiments with varying treatments, sites, and durations. We investigated dwarf birch apical stem growth responses to a wide range of ecological factors (enhanced summer temperatures, deepened snow, caribou exclusion, factorial high level nitrogen and phosphorus additions, and low level nitrogen additions) after six years of experimental manipulations in birch hummock tundra. As expected, birch apical stem growth was more strongly enhanced by the substantial increases in nutrient supply than by our changes in any of the other ecological factors. The factorial additions revealed that P availability was at least as important as that of N, and our low N additions demonstrated that growth was unresponsive to moderate increases in soil nitrogen alone. Experimental warming increased apical stem growth 2.5-fold—considerably more than in past studies—probably due to the relatively strong effect of our greenhouses on soil temperature. Together, these results have important implications for our understanding of the biogeochemical functioning of mesic tundra ecosystems as well as predicting their vegetation responses to climate change. Article in Journal/Newspaper albedo Arctic Climate change Dwarf birch Tundra Directory of Open Access Journals: DOAJ Articles Arctic Environmental Research Letters 7 3 034027 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
shrub expansion Arctic tundra climate change experimental warming fertilization nutrient limitation Environmental technology. Sanitary engineering TD1-1066 Environmental sciences GE1-350 Science Q Physics QC1-999 |
spellingShingle |
shrub expansion Arctic tundra climate change experimental warming fertilization nutrient limitation Environmental technology. Sanitary engineering TD1-1066 Environmental sciences GE1-350 Science Q Physics QC1-999 Tara J Zamin Paul Grogan Birch shrub growth in the low Arctic: the relative importance of experimental warming, enhanced nutrient availability, snow depth and caribou exclusion |
topic_facet |
shrub expansion Arctic tundra climate change experimental warming fertilization nutrient limitation Environmental technology. Sanitary engineering TD1-1066 Environmental sciences GE1-350 Science Q Physics QC1-999 |
description |
Deciduous shrub growth has increased across the Arctic simultaneously with recent climate warming trends. The reduction in albedo associated with shrub-induced ‘greening’ of the tundra is predicted to cause significant positive feedbacks to regional warming. Enhanced soil fertility arising from climate change is expected to be the primary mechanism driving shrub responses, yet our overall understanding of the relative importance of soil nitrogen (N) and phosphorus (P) availability and the significance of other ecological drivers is constrained by experiments with varying treatments, sites, and durations. We investigated dwarf birch apical stem growth responses to a wide range of ecological factors (enhanced summer temperatures, deepened snow, caribou exclusion, factorial high level nitrogen and phosphorus additions, and low level nitrogen additions) after six years of experimental manipulations in birch hummock tundra. As expected, birch apical stem growth was more strongly enhanced by the substantial increases in nutrient supply than by our changes in any of the other ecological factors. The factorial additions revealed that P availability was at least as important as that of N, and our low N additions demonstrated that growth was unresponsive to moderate increases in soil nitrogen alone. Experimental warming increased apical stem growth 2.5-fold—considerably more than in past studies—probably due to the relatively strong effect of our greenhouses on soil temperature. Together, these results have important implications for our understanding of the biogeochemical functioning of mesic tundra ecosystems as well as predicting their vegetation responses to climate change. |
format |
Article in Journal/Newspaper |
author |
Tara J Zamin Paul Grogan |
author_facet |
Tara J Zamin Paul Grogan |
author_sort |
Tara J Zamin |
title |
Birch shrub growth in the low Arctic: the relative importance of experimental warming, enhanced nutrient availability, snow depth and caribou exclusion |
title_short |
Birch shrub growth in the low Arctic: the relative importance of experimental warming, enhanced nutrient availability, snow depth and caribou exclusion |
title_full |
Birch shrub growth in the low Arctic: the relative importance of experimental warming, enhanced nutrient availability, snow depth and caribou exclusion |
title_fullStr |
Birch shrub growth in the low Arctic: the relative importance of experimental warming, enhanced nutrient availability, snow depth and caribou exclusion |
title_full_unstemmed |
Birch shrub growth in the low Arctic: the relative importance of experimental warming, enhanced nutrient availability, snow depth and caribou exclusion |
title_sort |
birch shrub growth in the low arctic: the relative importance of experimental warming, enhanced nutrient availability, snow depth and caribou exclusion |
publisher |
IOP Publishing |
publishDate |
2012 |
url |
https://doi.org/10.1088/1748-9326/7/3/034027 https://doaj.org/article/5ecb58fcd471429696935059710372f6 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
albedo Arctic Climate change Dwarf birch Tundra |
genre_facet |
albedo Arctic Climate change Dwarf birch Tundra |
op_source |
Environmental Research Letters, Vol 7, Iss 3, p 034027 (2012) |
op_relation |
https://doi.org/10.1088/1748-9326/7/3/034027 https://doaj.org/toc/1748-9326 doi:10.1088/1748-9326/7/3/034027 1748-9326 https://doaj.org/article/5ecb58fcd471429696935059710372f6 |
op_doi |
https://doi.org/10.1088/1748-9326/7/3/034027 |
container_title |
Environmental Research Letters |
container_volume |
7 |
container_issue |
3 |
container_start_page |
034027 |
_version_ |
1776204962622078976 |