| Full text | |
| Author(s): |
Pugliese Andrade, Gabriel Ramatis
[1]
;
Cuadros, Javier
[2]
;
Peniche Barbosa, Jorge Marcos
[1]
;
Vidal-Torrado, Pablo
[3]
Total Authors: 4
|
| Affiliation: | [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
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | CATENA; v. 209, n. 2 FEB 2022. |
| Web of Science Citations: | 0 |
| Abstract | |
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) | |
| FAPESP's process: | 13/17571-0 - XRD modeling and peak decomposition procedures applied to the study of clay minerals in Brazilian mangrove soils |
| Grantee: | Gabriel Ramatis Pugliese Andrade |
| Support Opportunities: | Scholarships abroad - Research Internship - Doctorate |
| FAPESP's process: | 09/51453-0 - Mineralogy of mangrove soils of Brazilian coast |
| Grantee: | Pablo Vidal Torrado |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 11/13924-0 - Genesis and characterization of clay minerals from mangrove soils of Brazilian coast |
| Grantee: | Gabriel Ramatis Pugliese Andrade |
| Support Opportunities: | Scholarships in Brazil - Doctorate |