Changes in Nutrient Sources for Arctic Tundra Vegetation upon Permafrost Thaw

Permafrost thaw modifies resource acquisition for tundra vegetation in two major directions of vegetation shift across the Arctic: the expansion of deeply rooted sedges and the widespread increase in shallowly rooted woody shrubs. Assessing to what extent nutrient access is changing for the Arctic t...

Full description

Bibliographic Details
Main Authors: Villani, Maëlle, Mauclet, Elisabeth, Gérard, Merlin, Hirst, Catherine, Monhonval, Arthur, Stevenson, Emily, Schuur, Edward, Opfergelt, Sophie, AGU Fall Meeting 2022
Other Authors: UCL - SST/ELI/ELIE - Environmental Sciences
Format: Conference Object
Language:English
Published: 2022
Subjects:
Online Access:http://hdl.handle.net/2078.1/268694
id ftunistlouisbrus:oai:dial.uclouvain.be:boreal:268694
record_format openpolar
spelling ftunistlouisbrus:oai:dial.uclouvain.be:boreal:268694 2024-05-12T07:52:21+00:00 Changes in Nutrient Sources for Arctic Tundra Vegetation upon Permafrost Thaw Villani, Maëlle Mauclet, Elisabeth Gérard, Merlin Hirst, Catherine Monhonval, Arthur Stevenson, Emily Schuur, Edward Opfergelt, Sophie AGU Fall Meeting 2022 UCL - SST/ELI/ELIE - Environmental Sciences 2022 http://hdl.handle.net/2078.1/268694 eng eng info:eu-repo/grantAgreement/European Research Council (ERC)/European Union’s Horizon 2020 research and innovation programme/grant agreement nâ—¦714617 boreal:268694 http://hdl.handle.net/2078.1/268694 Permafrost vegetation nutrients strontium info:eu-repo/semantics/conferenceObject 2022 ftunistlouisbrus 2024-04-18T17:09:55Z Permafrost thaw modifies resource acquisition for tundra vegetation in two major directions of vegetation shift across the Arctic: the expansion of deeply rooted sedges and the widespread increase in shallowly rooted woody shrubs. Assessing to what extent nutrient access is changing for the Arctic tundra vegetation development is crucial given the feedbacks of vegetation shifts on Arctic warming and permafrost stability by influencing the albedo, the snow accumulation and the litter decomposition rate. In this study, we evaluate the influence of permafrost degradation on the nutrient sources for plant uptake by using the radiogenic Sr isotope ratio as a tracer of source for plant nutrient, along a permafrost thaw gradient at Eight Mile Lake in Interior Alaska (USA). As plants take up Sr from the exchangeable soil fraction with no measurable fractionation, we determine the differences in 87Sr/86Sr ratio of the exchangeable Sr between shallow and deeper soil horizons, and we compare the 87Sr/86Sr ratio of foliar samples for three Arctic tundra species with contrasted rooting depths (B. nana, V. vitis-idaea, and E. vaginatum) upon different permafrost thaw conditions. The higher foliar 87Sr/86Sr ratios of shallow-rooted Arctic tundra shrubs (B. nana, V. vitis-idaea) reflect a shallow source of soil exchangeable Sr from surface soil horizons, whereas the lower foliar 87Sr/86Sr ratios of deep-rooted Arctic tundra sedges (E. vaginatum) reflect a source of Sr from deeper soil horizons. Importantly, our data highlight a shift in the range of foliar 87Sr/86Sr ratios towards lower values in plants grown on more deeply thawed permafrost soils, thereby supporting that the three Arctic tundra plant species access nutrients from deeper soil horizons upon permafrost thaw. The differences in plant strategy for nutrient acquisition is therefore expected to influence largely interactions between deeply and shallowly rooted plant species, and thereby the future shift in Arctic tundra vegetation. Conference Object albedo Arctic permafrost Tundra Alaska DIAL@USL-B (Université Saint-Louis, Bruxelles) Arctic
institution Open Polar
collection DIAL@USL-B (Université Saint-Louis, Bruxelles)
op_collection_id ftunistlouisbrus
language English
topic Permafrost
vegetation
nutrients
strontium
spellingShingle Permafrost
vegetation
nutrients
strontium
Villani, Maëlle
Mauclet, Elisabeth
Gérard, Merlin
Hirst, Catherine
Monhonval, Arthur
Stevenson, Emily
Schuur, Edward
Opfergelt, Sophie
AGU Fall Meeting 2022
Changes in Nutrient Sources for Arctic Tundra Vegetation upon Permafrost Thaw
topic_facet Permafrost
vegetation
nutrients
strontium
description Permafrost thaw modifies resource acquisition for tundra vegetation in two major directions of vegetation shift across the Arctic: the expansion of deeply rooted sedges and the widespread increase in shallowly rooted woody shrubs. Assessing to what extent nutrient access is changing for the Arctic tundra vegetation development is crucial given the feedbacks of vegetation shifts on Arctic warming and permafrost stability by influencing the albedo, the snow accumulation and the litter decomposition rate. In this study, we evaluate the influence of permafrost degradation on the nutrient sources for plant uptake by using the radiogenic Sr isotope ratio as a tracer of source for plant nutrient, along a permafrost thaw gradient at Eight Mile Lake in Interior Alaska (USA). As plants take up Sr from the exchangeable soil fraction with no measurable fractionation, we determine the differences in 87Sr/86Sr ratio of the exchangeable Sr between shallow and deeper soil horizons, and we compare the 87Sr/86Sr ratio of foliar samples for three Arctic tundra species with contrasted rooting depths (B. nana, V. vitis-idaea, and E. vaginatum) upon different permafrost thaw conditions. The higher foliar 87Sr/86Sr ratios of shallow-rooted Arctic tundra shrubs (B. nana, V. vitis-idaea) reflect a shallow source of soil exchangeable Sr from surface soil horizons, whereas the lower foliar 87Sr/86Sr ratios of deep-rooted Arctic tundra sedges (E. vaginatum) reflect a source of Sr from deeper soil horizons. Importantly, our data highlight a shift in the range of foliar 87Sr/86Sr ratios towards lower values in plants grown on more deeply thawed permafrost soils, thereby supporting that the three Arctic tundra plant species access nutrients from deeper soil horizons upon permafrost thaw. The differences in plant strategy for nutrient acquisition is therefore expected to influence largely interactions between deeply and shallowly rooted plant species, and thereby the future shift in Arctic tundra vegetation.
author2 UCL - SST/ELI/ELIE - Environmental Sciences
format Conference Object
author Villani, Maëlle
Mauclet, Elisabeth
Gérard, Merlin
Hirst, Catherine
Monhonval, Arthur
Stevenson, Emily
Schuur, Edward
Opfergelt, Sophie
AGU Fall Meeting 2022
author_facet Villani, Maëlle
Mauclet, Elisabeth
Gérard, Merlin
Hirst, Catherine
Monhonval, Arthur
Stevenson, Emily
Schuur, Edward
Opfergelt, Sophie
AGU Fall Meeting 2022
author_sort Villani, Maëlle
title Changes in Nutrient Sources for Arctic Tundra Vegetation upon Permafrost Thaw
title_short Changes in Nutrient Sources for Arctic Tundra Vegetation upon Permafrost Thaw
title_full Changes in Nutrient Sources for Arctic Tundra Vegetation upon Permafrost Thaw
title_fullStr Changes in Nutrient Sources for Arctic Tundra Vegetation upon Permafrost Thaw
title_full_unstemmed Changes in Nutrient Sources for Arctic Tundra Vegetation upon Permafrost Thaw
title_sort changes in nutrient sources for arctic tundra vegetation upon permafrost thaw
publishDate 2022
url http://hdl.handle.net/2078.1/268694
geographic Arctic
geographic_facet Arctic
genre albedo
Arctic
permafrost
Tundra
Alaska
genre_facet albedo
Arctic
permafrost
Tundra
Alaska
op_relation info:eu-repo/grantAgreement/European Research Council (ERC)/European Union’s Horizon 2020 research and innovation programme/grant agreement n◦714617
boreal:268694
http://hdl.handle.net/2078.1/268694
_version_ 1798854800824074240