| Texto completo | |
| Autor(es): |
Pugliese Andrade, Gabriel Ramatis
[1]
;
Cuadros, Javier
[2]
;
Peniche Barbosa, Jorge Marcos
[1]
;
Vidal-Torrado, Pablo
[3]
Número total de Autores: 4
|
| Afiliação do(s) autor(es): | [1] Univ Estadual Norte Fluminense, Lab Solos CCTA, Av Alberto Larnego 2000, BR-28013602 Campos Dos Goytacazes, RJ - Brazil
[2] Nat Hist Museum, Dept Earth Sci, Cromwell Rd, London SW7 5BD - England
[3] Univ Sao Paulo ESALQ USP, Escola Super Agr Luiz de Queiroz, Dept Ciencia Solo, Av Padua Dias 11, CP9, BR-13418900 Piracicaba, SP - Brazil
Número total de Afiliações: 3
|
| Tipo de documento: | Artigo Científico |
| Fonte: | CATENA; v. 209, n. 2 FEB 2022. |
| Citações Web of Science: | 0 |
| Resumo | |
Mangroves are intertidal tropical ecosystems influenced by marine and terrigenous input. They are important sinks of trace elements, like Rare Earth Elements (REE), which are recognized as excellent indicators of geochemical processes in estuaries. REE data of bulk soil samples from eight mangroves located along the Brazilian coast were correlated with quantitative clay mineral data based on XRD full-profile modelling. Kaolinite has been found to transform to Fe-illite in these mangroves. The clay assemblage was dominated by interstratified phases, including kaolinite-smectite (kaolinite and smectite-rich), illite-smectite and other illitic phases. REE concentrations in bulk soils were LREE > MREE > HREE (where L, M and H indicate light, medium and heavy). Multivariate statistical approach (PCA analysis) using clay mineral concentrations and proxies for relative REE concentrations ({[}La/Gd](N), {[}La/Yb](N) and {[}Gd/Yb](N) ratios) showed (r > 0.75) that fractionation of LREE over HREE was highest in mangroves where kaolinite, fed with the highly weathered sediments form the Neogene Barreiras Group, was most abundant (67-85% of all clay minerals), while REE fractionation decreased as the relative proportion of Fe-rich smectite increased (26-46 % of all clay minerals). Identified processes of REE control are: 1) Level of sediment weathering within the continent, where higher weathering implies higher kaolinite content and higher REE fractionation (LREE > MREE > HREE); 2) selective leaching of LREE from mangrove soils by saline water; 3) preferential adsorption of HREE by Fe-rich smectite and illite neoformed in the mangrove soils. It is possible to conclude that clay minerals exert an important control on REE fractionation in tropical mangroves. (AU) | |
| Processo FAPESP: | 13/17571-0 - Modelagem de DRX e procedimentos de decomposição de picos aplicados ao estudo de argilominerais em solos de manguezais brasileiros |
| Beneficiário: | Gabriel Ramatis Pugliese Andrade |
| Modalidade de apoio: | Bolsas no Exterior - Estágio de Pesquisa - Doutorado |
| Processo FAPESP: | 09/51453-0 - Mineralogia de solos de manguezais da costa brasileira |
| Beneficiário: | Pablo Vidal Torrado |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 11/13924-0 - Caracterização e gênese de minerais da fração argila de solos de manguezais da costa brasileira |
| Beneficiário: | Gabriel Ramatis Pugliese Andrade |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |