Phytostabilization of Mine Tailings in Arid and Semiarid Environments—An Emerging Remediation Technology

Abstract

ObjectiveUnreclaimed mine tailings sites are a worldwide problem, with thousands of unvegetated, exposed tailings piles presenting a source of contamination for nearby communities. Tailings disposal sites in arid and semiarid environments are especially subject to eolian dispersion and water erosion. Phytostabilization, the use of plants for in situ stabilization of tailings and metal contaminants, is a feasible alternative to costly remediation practices. In this review we emphasize considerations for phytostabilization of mine tailings in arid and semiarid environments, as well as issues impeding its long-term success.Data sourcesWe reviewed literature addressing mine closures and revegetation of mine tailings, along with publications evaluating plant ecology, microbial ecology, and soil properties of mine tailings.Data extractionData were extracted from peer-reviewed articles and books identified in Web of Science and Agricola databases, and publications available through the U.S. Department of Agriculture, U.S. Environmental Protection Agency, and the United Nations Environment Programme.Data synthesisHarsh climatic conditions in arid and semiarid environments along with the innate properties of mine tailings require specific considerations. Plants suitable for phytostabilization must be native, be drought-, salt-, and metal-tolerant, and should limit shoot metal accumulation. Factors for evaluating metal accumulation and toxicity issues are presented. Also reviewed are aspects of implementing phytostabilization, including plant growth stage, amendments, irrigation, and evaluation.ConclusionsPhytostabilization of mine tailings is a promising remedial technology but requires further research to identify factors affecting its long-term success by expanding knowledge of suitable plant species and mine tailings chemistry in ongoing field trials.

In vitro multiplication of Dianthus carthusianorum calamine ecotype with the aim to revegetate and stabilize polluted wastes

“…It is now widely accepted that stabilization of wastes disposed after ore exploitation by vegetation cover is far more desirable than physical or chemical methods of remediation (Tordoff et al 2000;Mendez and Maier 2008;Sheoran et al 2013;Yang et al 2016). Successful revegetation is treated as an ecologically justified, permanent, visually attractive and relatively inexpensive solution.…”

Progresses in restoration of post-mining landscape in Africa

“…The natural colonization of post-mining soils is slow due to poor soil quality, thus establishing a stable plant cover is the starting point for successful restoration using biological methods (Conesa et al 2007a, b). Phytoremediation basically includes phytoextraction-uptake and translocation of heavy metals by plants, and phytostabilization-the use of plant species as well as soil amendments to immobilize heavy metals through absorption and accumulation by roots, adsorption onto roots, or precipitation within the rhizosphere (Mendez and Maier 2008;Bolan et al 2011). Plants suitable for phytoremediation have two major heavy metal resistance strategies, viz.…”

Accumulation and distribution of lead (Pb) in plant tissues of guar (Cyamopsis tetragonolobaL.) and sesame (Sesamum indicumL.): profitable phytoremediation with biofuel crops

“…Plants with BCF, BAC, and TF values > 1 are considered promising phytoextractor, suitable for phytoextraction, while those with BCF and TF < 1 are not suitable for phytoextraction/phytostabilzation (Fitz & Wenzel, 2002). However, plants with BCF > 1 and TF < 1 are considered potential phytostabilizers (Mendez & Maier, 2008), suitable for phytostabilziation (immobilization). Between tested plant species, C. tetragonoloba had BCF values > 1 from 100 to 600 mg Pb kg −1 while, BAC and TF values < 1 at all Pb treatments, indicating that C. tetragonoloba could not be a high efficiency plant for Pb translocation from root to the shoot; but suitable for Pb phytostabilzation.…”