Effects of arctic shrub expansion on biophysical vs. biogeochemical drivers of litter decomposition
Climate warming in arctic tundra may shift dominant vegetation from graminoids to deciduous shrubs, whose functional traits could, in turn, alter biotic and abiotic controls over biogeochemical cycling of carbon (C) and nitrogen (N). We investigated whether shrub‐induced changes in microclimate have...
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crwiley:10.1890/13-2221.1 2024-09-15T18:39:45+00:00 Effects of arctic shrub expansion on biophysical vs. biogeochemical drivers of litter decomposition DeMarco, Jennie Mack, Michelle C. Bret-Harte, M. Syndonia 2014 http://dx.doi.org/10.1890/13-2221.1 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1890%2F13-2221.1 https://esajournals.onlinelibrary.wiley.com/doi/pdf/10.1890/13-2221.1 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Ecology volume 95, issue 7, page 1861-1875 ISSN 0012-9658 1939-9170 journal-article 2014 crwiley https://doi.org/10.1890/13-2221.1 2024-08-01T04:23:06Z Climate warming in arctic tundra may shift dominant vegetation from graminoids to deciduous shrubs, whose functional traits could, in turn, alter biotic and abiotic controls over biogeochemical cycling of carbon (C) and nitrogen (N). We investigated whether shrub‐induced changes in microclimate have stronger effects on litter decomposition and nutrient release than changes in litter quality and quantity. In arctic tundra near Toolik Lake, Alaska, USA, we incubated a common substrate in a snow‐addition experiment to test whether snow accumulation around arctic deciduous shrubs altered the environment enough to increase litter decomposition rates. We compared the influence of litter quality on the rate of litter and N loss by decomposing litter from four different plant functional types in a common site. We used aboveground net primary production values and estimated decay constant ( k ) values from our decomposition experiments to calculate community‐weighted mass loss for each site. Snow addition had no effect on decomposition of the common substrate, and the site with the highest abundance of shrubs had the lowest decomposition rates. Species varied in their decomposition rates, with species from the same functional type not always following similar patterns. Community‐weighted mass loss was 1.5 times greater in the high shrub site, and only slightly decreased when adjusted for soil environment, suggesting that litter quality and quantity are the primary drivers of community decomposition. Our findings suggest that on a short time scale, the changes in soil environment associated with snow trapping by shrubs are unlikely to influence litter nutrient turnover enough to drive positive snow–shrub feedbacks. The mechanisms driving shrub expansion are more likely to do with shrub–litter feedbacks, where the higher growth rates and N uptake by shrubs allows them to produce more leaves, resulting in a larger litter N pool and faster internal cycling of nutrients. Article in Journal/Newspaper Tundra Alaska Wiley Online Library Ecology 95 7 1861 1875 |
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English |
description |
Climate warming in arctic tundra may shift dominant vegetation from graminoids to deciduous shrubs, whose functional traits could, in turn, alter biotic and abiotic controls over biogeochemical cycling of carbon (C) and nitrogen (N). We investigated whether shrub‐induced changes in microclimate have stronger effects on litter decomposition and nutrient release than changes in litter quality and quantity. In arctic tundra near Toolik Lake, Alaska, USA, we incubated a common substrate in a snow‐addition experiment to test whether snow accumulation around arctic deciduous shrubs altered the environment enough to increase litter decomposition rates. We compared the influence of litter quality on the rate of litter and N loss by decomposing litter from four different plant functional types in a common site. We used aboveground net primary production values and estimated decay constant ( k ) values from our decomposition experiments to calculate community‐weighted mass loss for each site. Snow addition had no effect on decomposition of the common substrate, and the site with the highest abundance of shrubs had the lowest decomposition rates. Species varied in their decomposition rates, with species from the same functional type not always following similar patterns. Community‐weighted mass loss was 1.5 times greater in the high shrub site, and only slightly decreased when adjusted for soil environment, suggesting that litter quality and quantity are the primary drivers of community decomposition. Our findings suggest that on a short time scale, the changes in soil environment associated with snow trapping by shrubs are unlikely to influence litter nutrient turnover enough to drive positive snow–shrub feedbacks. The mechanisms driving shrub expansion are more likely to do with shrub–litter feedbacks, where the higher growth rates and N uptake by shrubs allows them to produce more leaves, resulting in a larger litter N pool and faster internal cycling of nutrients. |
format |
Article in Journal/Newspaper |
author |
DeMarco, Jennie Mack, Michelle C. Bret-Harte, M. Syndonia |
spellingShingle |
DeMarco, Jennie Mack, Michelle C. Bret-Harte, M. Syndonia Effects of arctic shrub expansion on biophysical vs. biogeochemical drivers of litter decomposition |
author_facet |
DeMarco, Jennie Mack, Michelle C. Bret-Harte, M. Syndonia |
author_sort |
DeMarco, Jennie |
title |
Effects of arctic shrub expansion on biophysical vs. biogeochemical drivers of litter decomposition |
title_short |
Effects of arctic shrub expansion on biophysical vs. biogeochemical drivers of litter decomposition |
title_full |
Effects of arctic shrub expansion on biophysical vs. biogeochemical drivers of litter decomposition |
title_fullStr |
Effects of arctic shrub expansion on biophysical vs. biogeochemical drivers of litter decomposition |
title_full_unstemmed |
Effects of arctic shrub expansion on biophysical vs. biogeochemical drivers of litter decomposition |
title_sort |
effects of arctic shrub expansion on biophysical vs. biogeochemical drivers of litter decomposition |
publisher |
Wiley |
publishDate |
2014 |
url |
http://dx.doi.org/10.1890/13-2221.1 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1890%2F13-2221.1 https://esajournals.onlinelibrary.wiley.com/doi/pdf/10.1890/13-2221.1 |
genre |
Tundra Alaska |
genre_facet |
Tundra Alaska |
op_source |
Ecology volume 95, issue 7, page 1861-1875 ISSN 0012-9658 1939-9170 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1890/13-2221.1 |
container_title |
Ecology |
container_volume |
95 |
container_issue |
7 |
container_start_page |
1861 |
op_container_end_page |
1875 |
_version_ |
1810484099381460992 |