Dre Laure Gandois - Origin and composition of dissolved organic matter in thaw-affected permafrost peatlands of North Siberia

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Dre Laure Gandois, EcoLab (Laboratoire Écologie fonctionnelle et Environnement), Université de Toulouse, CNRS, INPT, UPS, Toulouse, France

Jeudi 20 juin 2019 à 14h00 - Thrusday, June 20th, 2019 at 2:00 pm

Local PK-7605, 201 ave. Président-Kennedy, UQAM

Résumé/Abstract:

In a warming Arctic, permafrost thaw is expected to affect ecosystems storing half of the global soil organic carbon stocks. If this long-term sequestered organic carbon stock is released into the active carbon cycle, it could induce a positive feedback to climate change. Dissolved organic matter (DOM) is the most dynamic but least characterized carbon pool within terrestrial ecosystems, especially in the Arctic terrestrial ecosystems, and is a potentially important conduit for the release of permafrost carbon following thaw. In this talk, we will present the results of investigation of DOM dynamics, conducted in a discontinuous permafrost area of North Siberia. We investigated the origin and composition of DOM, across sites at different stages of permafrost thaw, combining optical properties, molecular composition, stable and radiocarbon content of DOM. We show that the relative contribution of peatland carbon to DOM controls its composition.

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Origin and composition of dissolved organic matter in thaw-affected permafrost peatlands of North Siberia

Ajouter au calendrier 2019-06-20 14:00:00 2019-06-15 06:21:47 Dre Laure Gandois - Origin and composition of dissolved organic matter in thaw-affected permafrost peatlands of North Siberia Résumé/Abstract: In a warming Arctic, permafrost thaw is expected to affect ecosystems storing half of the global soil organic carbon stocks. If this long-term sequestered organic carbon stock is released into the active carbon cycle, it could induce a positive feedback to climate change. Dissolved organic matter (DOM) is the most dynamic but least characterized carbon pool within terrestrial ecosystems, especially in the Arctic terrestrial ecosystems, and is a potentially important conduit for the release of permafrost carbon following thaw. In this talk, we will present the results of investigation of DOM dynamics, conducted in a discontinuous permafrost area of North Siberia. We investigated the origin and composition of DOM, across sites at different stages of permafrost thaw, combining optical properties, molecular composition, stable and radiocarbon content of DOM. We show that the relative contribution of peatland carbon to DOM controls its composition. Local PK-7605, 201 ave. Président-Kennedy, UQAM Geotop admin@example.com America/New_York public