High nitrate variability on an Alaskan permafrost hillslope dominated by alder shrubs
In Arctic ecosystems, increasing temperatures are driving the expansion of nitrogen (N) fixing shrubs across tundra landscapes. The implications of this expansion to the biogeochemistry of Arctic ecosystems are of critical importance and more work is needed to better understand the form, availabilit...
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Online Access: | http://www.osti.gov/servlets/purl/1869134 https://www.osti.gov/biblio/1869134 https://doi.org/10.5194/tc-16-1889-2022 |
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ftosti:oai:osti.gov:1869134 2023-07-30T04:01:02+02:00 High nitrate variability on an Alaskan permafrost hillslope dominated by alder shrubs McCaully, Rachael E. Arendt, Carli A. Newman, Brent D. Salmon, Verity G. Heikoop, Jeffrey M. Wilson, Cathy J. Sevanto, Sanna Wales, Nathan A. Perkins, George B. Marina, Oana C. Wullschleger, Stan D. 2023-02-23 application/pdf http://www.osti.gov/servlets/purl/1869134 https://www.osti.gov/biblio/1869134 https://doi.org/10.5194/tc-16-1889-2022 unknown http://www.osti.gov/servlets/purl/1869134 https://www.osti.gov/biblio/1869134 https://doi.org/10.5194/tc-16-1889-2022 doi:10.5194/tc-16-1889-2022 54 ENVIRONMENTAL SCIENCES 2023 ftosti https://doi.org/10.5194/tc-16-1889-2022 2023-07-11T10:12:33Z In Arctic ecosystems, increasing temperatures are driving the expansion of nitrogen (N) fixing shrubs across tundra landscapes. The implications of this expansion to the biogeochemistry of Arctic ecosystems are of critical importance and more work is needed to better understand the form, availability, and transportation potential of N from these shrubs across a variety of Arctic landscapes. To gain insights into the processes controlling N within a permafrost hillslope system, the spatiotemporal variability of nitrate (NO$_{3}^{-}$) and its environmental controls were investigated at an alder (Alnus viridis spp. fruticosa) dominated permafrost tundra landscape in the Seward Peninsula, Alaska, USA. Soil pore water was collected from locations within alder shrubland growing along a well-drained hillslope and was compared to soil pore water collected from locations outside (upslope, downslope, and between) the alder shrubland. Soil pore water collected within alder shrubland had an average NO 3 - N (nitrogen from nitrate) concentration of 4.27±8.02 mg L -1 and differed significantly from locations outside alder shrubland (0.23±0.83 mg L -1 p<0.05). Temporal variation in NO 3 - N within and downslope of alder shrubland co-occurred with precipitation events where NO$_{3}^{-}$ that accumulated in the soil was likely flushed downslope during rainfall. These findings have important implications for nutrient availability and mobility in N-limited permafrost systems that are experiencing shrub expansion in response to a warming Arctic. Other/Unknown Material Arctic permafrost Seward Peninsula Tundra Alaska SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Arctic The Cryosphere 16 5 1889 1901 |
institution |
Open Polar |
collection |
SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
op_collection_id |
ftosti |
language |
unknown |
topic |
54 ENVIRONMENTAL SCIENCES |
spellingShingle |
54 ENVIRONMENTAL SCIENCES McCaully, Rachael E. Arendt, Carli A. Newman, Brent D. Salmon, Verity G. Heikoop, Jeffrey M. Wilson, Cathy J. Sevanto, Sanna Wales, Nathan A. Perkins, George B. Marina, Oana C. Wullschleger, Stan D. High nitrate variability on an Alaskan permafrost hillslope dominated by alder shrubs |
topic_facet |
54 ENVIRONMENTAL SCIENCES |
description |
In Arctic ecosystems, increasing temperatures are driving the expansion of nitrogen (N) fixing shrubs across tundra landscapes. The implications of this expansion to the biogeochemistry of Arctic ecosystems are of critical importance and more work is needed to better understand the form, availability, and transportation potential of N from these shrubs across a variety of Arctic landscapes. To gain insights into the processes controlling N within a permafrost hillslope system, the spatiotemporal variability of nitrate (NO$_{3}^{-}$) and its environmental controls were investigated at an alder (Alnus viridis spp. fruticosa) dominated permafrost tundra landscape in the Seward Peninsula, Alaska, USA. Soil pore water was collected from locations within alder shrubland growing along a well-drained hillslope and was compared to soil pore water collected from locations outside (upslope, downslope, and between) the alder shrubland. Soil pore water collected within alder shrubland had an average NO 3 - N (nitrogen from nitrate) concentration of 4.27±8.02 mg L -1 and differed significantly from locations outside alder shrubland (0.23±0.83 mg L -1 p<0.05). Temporal variation in NO 3 - N within and downslope of alder shrubland co-occurred with precipitation events where NO$_{3}^{-}$ that accumulated in the soil was likely flushed downslope during rainfall. These findings have important implications for nutrient availability and mobility in N-limited permafrost systems that are experiencing shrub expansion in response to a warming Arctic. |
author |
McCaully, Rachael E. Arendt, Carli A. Newman, Brent D. Salmon, Verity G. Heikoop, Jeffrey M. Wilson, Cathy J. Sevanto, Sanna Wales, Nathan A. Perkins, George B. Marina, Oana C. Wullschleger, Stan D. |
author_facet |
McCaully, Rachael E. Arendt, Carli A. Newman, Brent D. Salmon, Verity G. Heikoop, Jeffrey M. Wilson, Cathy J. Sevanto, Sanna Wales, Nathan A. Perkins, George B. Marina, Oana C. Wullschleger, Stan D. |
author_sort |
McCaully, Rachael E. |
title |
High nitrate variability on an Alaskan permafrost hillslope dominated by alder shrubs |
title_short |
High nitrate variability on an Alaskan permafrost hillslope dominated by alder shrubs |
title_full |
High nitrate variability on an Alaskan permafrost hillslope dominated by alder shrubs |
title_fullStr |
High nitrate variability on an Alaskan permafrost hillslope dominated by alder shrubs |
title_full_unstemmed |
High nitrate variability on an Alaskan permafrost hillslope dominated by alder shrubs |
title_sort |
high nitrate variability on an alaskan permafrost hillslope dominated by alder shrubs |
publishDate |
2023 |
url |
http://www.osti.gov/servlets/purl/1869134 https://www.osti.gov/biblio/1869134 https://doi.org/10.5194/tc-16-1889-2022 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic permafrost Seward Peninsula Tundra Alaska |
genre_facet |
Arctic permafrost Seward Peninsula Tundra Alaska |
op_relation |
http://www.osti.gov/servlets/purl/1869134 https://www.osti.gov/biblio/1869134 https://doi.org/10.5194/tc-16-1889-2022 doi:10.5194/tc-16-1889-2022 |
op_doi |
https://doi.org/10.5194/tc-16-1889-2022 |
container_title |
The Cryosphere |
container_volume |
16 |
container_issue |
5 |
container_start_page |
1889 |
op_container_end_page |
1901 |
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1772811756125552640 |