Phytostabilization potential of Erica australis L. and Nerium oleander L.: a comparative study in the Riotinto mining area (SW Spain)

Abstract

Phytostabilization is a green, cost-effective technique for mine rehabilitation and ecological restoration. In this study, the phytostabilization capacity of Erica australis L. and Nerium oleander L. was assessed in the climatic and geochemical context of the Riotinto mining district, southwestern Spain, where both plant species colonize harsh substrates of mine wastes and contaminated river banks. In addition to tolerating extreme acidic conditions (up to pH 3.36 for E. australis), both species were found to grow on substrates very poor in bioavailable nutrients (e.g., N and P) and highly enriched with potentially phytotoxic elements (e.g., Cu, Cd, Pb, S). The selective root absorption of essential elements and the sequestration of potentially toxic elements in the root cortex are the main adaptations that allow the studied species to cope in very limiting edaphic environments. Being capable of a tight elemental homeostatic control and tolerating extreme acidic conditions, E. australis is the best candidate for use in phytostabilization programs, ideally to promote early stages of colonization, improve physical and chemical conditions of substrates and favor the establishing of less tolerant species, such as N. oleander.

Phytoremediation: a sustainable environmental technology for heavy metals decontamination

“…Furthermore, roots accumulated more metals than leaves. Erica australis possesses the ability to uptake Cu, Cd and Pb via its roots without any sign of damage and suggest as a phytostabilizator species [123]. Bacchetta et al [13] indicated that Zn, Cd and Pb uptake was restricted largely in root tissue of Helichrysum microphyllum which is suitable for phytostabilization.…”

Phytoremediation of soils polluted with heavy metals in the vicinity of the Zenica steel mill in Bosnia and Herzegovina: potential for using native flora

“…On the other hand, phytostabilization is the ability of plants to reduce the mobility of heavy metals via absorption and accumulation by roots, adsorption onto roots or by changing the solubility of heavy metals by means of root exudates. Plants native to the polluted soil that can retain large quantities of metal ions in their roots or through root exudates lower their solubility are considered to be appropriate for phytostabilization (Monaci et al 2020). Although phytoremediation is not consistently effective, it is undoubtedly causes less damage to the environment than the use of chemicals and/or physical methods (Azubuike et al 2016).…”

Soil contamination and human health: part 2

“…Therefore, it is recommended that local residents should consume rice from the uncontaminated area, as well as reducing the amount of rice consumed. Monaci et al (2019) studied the phytostabilization capacity of Erica australis L. and Nerium oleander L. in the Riotinto mining area (SW Spain). The authors found that both species tolerate extreme acidic conditions, water-limited substrates, very poor in nutrients such N and P and highly enriched with phytotoxic elements (e.g.…”