Contrasting plant-induced changes in heavy metals dynamics: Implications for phytoremediation strategies in estuarine wetlands

Author(s)

Ferreira, Amanda Duim ; Queiroz, Hermano Melo ; Boim, Alexys G. Friol ; Duckworth, Owen W. ; Otero, Xose L. ; Bernardino, Angelo Fraga ; Ferreira, Tiago Osorio

• Document type: Journal article
• Source: ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY; v. 279, p. 11-pg., 2024-05-15.

Abstract

Wetland plants play a crucial role in regulating soil geochemistry, influencing heavy metal (HM) speciation, bioavailability, and uptake, thus impacting phytoremediation potential. We hypothesized that variations in HM biogeochemistry within estuarine soils are controlled by distinct estuarine plant species. We evaluated the soils (pH, redox potential, rhizosphere pH, HM total concentration, and geochemical fractionation), plant parts (shoot and root), and iron plaques of three plants growing in an estuary affected by Fe-rich mine tailings. Though the integration of multiple plant and soil analysis, this work emphasizes the importance of considering geochemical pools of HM for predicting their fate. Apart from the predominance of HM associated with Fe oxides, Typha domingensis accumulated the highest Cr and Ni contents in their shoots (> 100 mg kg(-1)). In contrast, Hibiscus tiliaceus accumulated more Cu and Pb in their roots (> 50 mg kg(-1)). The differences in rhizosphere soil conditions and root bioturbation explained the different potentials between the plants by altering the soil dynamics and HM's bioavailability, ultimately affecting their uptake. This study suggests that Eleocharis acutangula is not suitable for phytoextraction or phytostabilization, whereas Typha domingensis shows potential for Cr and Ni phytoextraction. In addition, we first showed Hibiscus tiliaceus as a promising wood species for Cu and Pb phytostabilization. (AU)

• FAPESP's process: 22/00296-6 - Siderophores amendment on Fe-rich mining tailings: screening a potential strategy for Fe phytomining
• Grantee: Amanda Duim Ferreira
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 21/00221-3 - From sinks to sources: vulnerability of mangrove soils as carbon sinks in the face of global climate change
• Grantee: Hermano Melo Queiroz
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/08408-2 - Comparative studies of the mineral transformation of iron oxide nanoparticles in mine-tailing affected sediments and soils and their impacts on mobilization and fixation of heavy metals under two contrasting redox environments
• Grantee: Tiago Osório Ferreira
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/14800-5 - Estuarine plants and their control in metals biogeochemistry in soils impacted by the `Mariana disaster´
• Grantee: Amanda Duim Ferreira
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 18/04259-2 - Iron biogeochemistry and its control on dynamics of trace metals in the soils of Doce River estuary after the "Mariana disaster"
• Grantee: Hermano Melo Queiroz
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 20/12823-5 - The impacts of Fe mine tailings in the oral bioaccessibility of potentially toxic elements: a study case on the world's largest mining disaster
• Grantee: Alexys Giorgia Friol Boim
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/19987-6 - Soils and plants of the Rio Doce estuary controlling the biogeochemistry of iron and metals in response to the Mariana (MG) disaster
• Grantee: Tiago Osório Ferreira
• Support Opportunities: Regular Research Grants