Greater deciduous shrub abundance extends tundra peak season and increases modeled net CO₂ uptake
Satellite studies of the terrestrial Arctic report increased summer greening and longer overall growing and peak seasons since the 1980s, which increases productivity and the period of carbon uptake. These trends are attributed to increasing air temperatures and reduced snow cover duration in spring...
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ftcolumbiauniv:oai:academiccommons.columbia.edu:10.7916/D80Z72QK 2023-05-15T15:01:55+02:00 Greater deciduous shrub abundance extends tundra peak season and increases modeled net CO₂ uptake Sweet, Shannan Kathlyn Griffin, Kevin L. Steltzer, Heidi Gough, Laura Boelman, Natalie T. 2015 https://doi.org/10.7916/D80Z72QK English eng John Wiley & Sons, Inc. https://doi.org/10.7916/D80Z72QK Vegetation and climate Carbon cycle (Biogeochemistry) Vegetation surveys--Remote sensing Plant phenology Ecology Environmental sciences Remote sensing Articles 2015 ftcolumbiauniv https://doi.org/10.7916/D80Z72QK 2019-04-04T08:13:19Z Satellite studies of the terrestrial Arctic report increased summer greening and longer overall growing and peak seasons since the 1980s, which increases productivity and the period of carbon uptake. These trends are attributed to increasing air temperatures and reduced snow cover duration in spring and fall. Concurrently, deciduous shrubs are becoming increasingly abundant in tundra landscapes, which may also impact canopy phenology and productivity. Our aim was to determine the influence of greater deciduous shrub abundance on tundra canopy phenology and subsequent impacts on net ecosystem carbon exchange (NEE) during the growing and peak seasons in the arctic foothills region of Alaska. We compared deciduous shrub-dominated and evergreen/graminoid-dominated community-level canopy phenology throughout the growing season using the normalized difference vegetation index (NDVI). We used a tundra plant-community-specific leaf area index (LAI) model to estimate LAI throughout the green season and a tundra-specific NEE model to estimate the impact of greater deciduous shrub abundance and associated shifts in both leaf area and canopy phenology on tundra carbon flux. We found that deciduous shrub canopies reached the onset of peak greenness 13 days earlier and the onset of senescence 3 days earlier compared to evergreen/graminoid canopies, resulting in a 10-day extension of the peak season. The combined effect of the longer peak season and greater leaf area of deciduous shrub canopies almost tripled the modeled net carbon uptake of deciduous shrub communities compared to evergreen/graminoid communities, while the longer peak season alone resulted in 84% greater carbon uptake in deciduous shrub communities. These results suggest that greater deciduous shrub abundance increases carbon uptake not only due to greater leaf area, but also due to an extension of the period of peak greenness, which extends the period of maximum carbon uptake. Article in Journal/Newspaper Arctic Tundra Alaska Columbia University: Academic Commons Arctic |
institution |
Open Polar |
collection |
Columbia University: Academic Commons |
op_collection_id |
ftcolumbiauniv |
language |
English |
topic |
Vegetation and climate Carbon cycle (Biogeochemistry) Vegetation surveys--Remote sensing Plant phenology Ecology Environmental sciences Remote sensing |
spellingShingle |
Vegetation and climate Carbon cycle (Biogeochemistry) Vegetation surveys--Remote sensing Plant phenology Ecology Environmental sciences Remote sensing Sweet, Shannan Kathlyn Griffin, Kevin L. Steltzer, Heidi Gough, Laura Boelman, Natalie T. Greater deciduous shrub abundance extends tundra peak season and increases modeled net CO₂ uptake |
topic_facet |
Vegetation and climate Carbon cycle (Biogeochemistry) Vegetation surveys--Remote sensing Plant phenology Ecology Environmental sciences Remote sensing |
description |
Satellite studies of the terrestrial Arctic report increased summer greening and longer overall growing and peak seasons since the 1980s, which increases productivity and the period of carbon uptake. These trends are attributed to increasing air temperatures and reduced snow cover duration in spring and fall. Concurrently, deciduous shrubs are becoming increasingly abundant in tundra landscapes, which may also impact canopy phenology and productivity. Our aim was to determine the influence of greater deciduous shrub abundance on tundra canopy phenology and subsequent impacts on net ecosystem carbon exchange (NEE) during the growing and peak seasons in the arctic foothills region of Alaska. We compared deciduous shrub-dominated and evergreen/graminoid-dominated community-level canopy phenology throughout the growing season using the normalized difference vegetation index (NDVI). We used a tundra plant-community-specific leaf area index (LAI) model to estimate LAI throughout the green season and a tundra-specific NEE model to estimate the impact of greater deciduous shrub abundance and associated shifts in both leaf area and canopy phenology on tundra carbon flux. We found that deciduous shrub canopies reached the onset of peak greenness 13 days earlier and the onset of senescence 3 days earlier compared to evergreen/graminoid canopies, resulting in a 10-day extension of the peak season. The combined effect of the longer peak season and greater leaf area of deciduous shrub canopies almost tripled the modeled net carbon uptake of deciduous shrub communities compared to evergreen/graminoid communities, while the longer peak season alone resulted in 84% greater carbon uptake in deciduous shrub communities. These results suggest that greater deciduous shrub abundance increases carbon uptake not only due to greater leaf area, but also due to an extension of the period of peak greenness, which extends the period of maximum carbon uptake. |
format |
Article in Journal/Newspaper |
author |
Sweet, Shannan Kathlyn Griffin, Kevin L. Steltzer, Heidi Gough, Laura Boelman, Natalie T. |
author_facet |
Sweet, Shannan Kathlyn Griffin, Kevin L. Steltzer, Heidi Gough, Laura Boelman, Natalie T. |
author_sort |
Sweet, Shannan Kathlyn |
title |
Greater deciduous shrub abundance extends tundra peak season and increases modeled net CO₂ uptake |
title_short |
Greater deciduous shrub abundance extends tundra peak season and increases modeled net CO₂ uptake |
title_full |
Greater deciduous shrub abundance extends tundra peak season and increases modeled net CO₂ uptake |
title_fullStr |
Greater deciduous shrub abundance extends tundra peak season and increases modeled net CO₂ uptake |
title_full_unstemmed |
Greater deciduous shrub abundance extends tundra peak season and increases modeled net CO₂ uptake |
title_sort |
greater deciduous shrub abundance extends tundra peak season and increases modeled net co₂ uptake |
publisher |
John Wiley & Sons, Inc. |
publishDate |
2015 |
url |
https://doi.org/10.7916/D80Z72QK |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Tundra Alaska |
genre_facet |
Arctic Tundra Alaska |
op_relation |
https://doi.org/10.7916/D80Z72QK |
op_doi |
https://doi.org/10.7916/D80Z72QK |
_version_ |
1766333916575170560 |