Spatially Resolved Organomineral Interactions across a Permafrost Chronosequence
Rattachement africain : us. Niveau de preuve : code pays fourni par la source.
Le résumé fourni par la source
Permafrost contains a large (1700 Pg C) terrestrial pool of organic matter (OM) that is susceptible to degradation as global temperatures increase. Of particular importance is syngenetic Yedoma permafrost containing high OM content. Reactive iron phases promote stabilizing interactions between OM and soil minerals and this stabilization may be of increasing importance in permafrost as the thawed surface region ("active layer") deepens. However, there is limited understanding of Fe and other soil mineral phase associations with OM carbon (C) moieties in permafrost soils. To elucidate the elemental associations involved in organomineral complexation within permafrost systems, soil cores spanning a Pleistocene permafrost chronosequence (19,000, 27,000, and 36,000 years old) were collected from an underground tunnel near Fairbanks, Alaska. Subsamples were analyzed via scanning transmission X-ray microscopy-near edge X-ray absorption fine structure spectroscopy at the nano- to microscale. Amino acid-rich moieties decreased in abundance across the chronosequence. Strong correlations between C and Fe with discrete Fe(III) or Fe(II) regions selectively associated with specific OM moieties were observed. Additionally, Ca coassociated with C through potential cation bridging mechanisms. Results indicate Fe(III), Fe(II), and mixed valence phases associated with OM throughout diverse permafrost environments, suggesting that organomineral complexation is crucial to predict C stability as permafrost systems warm.
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Le contrôle bibliographique ouvert
DOI retrouvé dans Crossref DOI retrouvé ; titre concordant.
- Titre Crossref
- Spatially Resolved Organomineral Interactions across a Permafrost Chronosequence
- Date Crossref
- 05/02/2020
- Éditeur
- American Chemical Society (ACS)
- Type
- journal-article
Ce recoupement confirme des métadonnées liées au DOI. Il ne confirme ni la méthode ni les conclusions de l’étude, et il ne compte pas comme une seconde source scientifique indépendante.
Où se fait cette recherche
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Environmental Protection Agency Office of Research and Development pays non établi dans la noticeOrganisme public
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Research Triangle Park Foundation pays non établi dans la noticeOrganisation à but non lucratif
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University of Delaware Delaware Environmental Institute pays non établi dans la noticeUniversité ou école supérieure
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Cold Regions Research and Engineering Laboratory pays non établi dans la noticeStructure de recherche
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United States Army pays non établi dans la noticeOrganisme public
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North Carolina State University Department of Crop and Soil Sciences pays non établi dans la noticeUniversité ou école supérieure
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U.S. Army Cold Regions Research & Engineering Laboratory pays non établi dans la noticeStructure de recherche
Office of Research and Development — Environmental Protection Agency, Research Triangle Park Foundation et Delaware Environmental Institute — University of Delaware, avec 4 autres affiliations.
Une affiliation ne permet pas de déduire la nationalité d’un auteur.