Geochemical evidence for arsenic cycling in living microbialites of a High Altitude Andean Lake (Laguna Diamante, Argentina) - Université de Montpellier Accéder directement au contenu
Article Dans Une Revue Chemical Geology Année : 2020

Geochemical evidence for arsenic cycling in living microbialites of a High Altitude Andean Lake (Laguna Diamante, Argentina)

Résumé

Arsenic is best known as an environmental toxin, but this element could also serve as a metabolic energy source to certain microorganisms. Moreover, As cycling may have driven microbial life on early Earth prior to oxygenation of the atmosphere. Still, little is known about the arsenic cycling processes occurring in the presence of microorganisms and the possible traces that could be preserved in the rock record. To advance our understanding of this we studied the geochemical proxies of microbial As metabolism in living microbialites from Laguna Diamante, a likely Precambrian ecosystem analogue (Catamarca, Argentina). In this study, we show that the coexistence of As(III) and As(V) strongly supports the presence of active microbially arsenic cycling in these microbialites. In addition, we propose a model by which arsenic metabolic processes can be preserved and interpreted as biosignatures in modern systems as well as in the rock record.

Domaines

Géochimie
Fichier principal
Vignette du fichier
Sancho-Tomas_psprint.pdf (7.74 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-02912566 , version 1 (15-12-2020)

Identifiants

Citer

Maria Sancho-Tomas, Andrea Somogyi, K. Medjoubi, Antoine Bergamaschi, Pieter T. Visscher, et al.. Geochemical evidence for arsenic cycling in living microbialites of a High Altitude Andean Lake (Laguna Diamante, Argentina). Chemical Geology, 2020, 549, pp.119681. ⟨10.1016/j.chemgeo.2020.119681⟩. ⟨hal-02912566⟩
159 Consultations
144 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More