Atmospheric iodine, selenium and caesium depositions in France: II. Influence of forest canopies.
Caesium
Forest tree species
Iodine
Selenium
Speciation
Throughfall
Journal
Chemosphere
ISSN: 1879-1298
Titre abrégé: Chemosphere
Pays: England
ID NLM: 0320657
Informations de publication
Date de publication:
Jun 2021
Jun 2021
Historique:
received:
24
08
2020
revised:
10
11
2020
accepted:
11
11
2020
pubmed:
25
11
2020
medline:
28
4
2021
entrez:
24
11
2020
Statut:
ppublish
Résumé
Estimation of the canopy influence on atmospheric inputs of iodine (I), selenium (Se) and caesium (Cs) in terrestrial ecosystems is an essential condition for appropriate biogeochemical models. However, the processes involved in rain composition modifications after its passage through forest canopy have been barely studied for these elements. We monitored I, Se and Cs concentrations in both rainfall and throughfall of fourteen French forested sites throughout one year, and estimated dry deposition and canopy exchange fluxes for these elements, as well as speciation of I and Se. Comparison of rainfall and throughfall elemental composition highlighted an important impact of forest canopy on both (i) concentrations and fluxes of I, Se and Cs, and (ii) I and Se species. For the three elements, most of their throughfall concentrations were higher than corresponding rainfall. The increase of throughfall elemental fluxes was mostly due to dry deposition for I and Se although the canopy exchange model revealed some sorption within the canopy in most cases; for Cs, foliage leaching was most influencing. Regarding speciation, iodine species in rainfall were highly modified by forest canopy with an important increase of unidentified I proportion in throughfall (on average 49 and 82% in rainfall and throughfall, respectively), possibly due to washoff of dry deposition and/or to transformation into organic forms. Similarly, while rainfall was composed of 26-54% of inorganic Se, inorganic species were undetectable in throughfall. This dataset represents key information to improve modelling of I, Se and Cs cycling within forest ecosystems.
Identifiants
pubmed: 33228989
pii: S0045-6535(20)33149-0
doi: 10.1016/j.chemosphere.2020.128952
pii:
doi:
Substances chimiques
Cesium
1KSV9V4Y4I
Iodine
9679TC07X4
Selenium
H6241UJ22B
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
128952Informations de copyright
Copyright © 2020 Elsevier Ltd. All rights reserved.
Déclaration de conflit d'intérêts
Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.