Conclusions and Outlook for Agromining

Abstract

The technology of agromining has created a new era in the recovery of strategic metals from natural or secondary resources, including industrial wastes. During the last decades, hyperaccumulator plants have changed recognition from merely a botanical curiosity to a prospect having tangible socio-economic and environmental applications. The knowledge base for this group of plant species, with unique properties capable of surviving and thriving in toxic and stressful environments, has increased greatly during the last 20 years, thanks to thorough investigations at various scales involving several disciplines, including botany, ecology, ecophysiology, microbiology, soil science and agronomy. The processes and mechanisms that preside over the hyperaccumulation of toxic metals and metalloids in plants are now better understood. For example, the fate and biopathways of elements in plants is actively being investigated using powerful new explanatory techniques, such as synchrotron and microprobe analysis. In addition, new species having exceptional ability to accumulate metals have been discovered, thereby considerably increasing the number of known hyperaccumulators. In parallel, work conducted by agronomists and soil scientists has allowed the domestication of selected hyperaccumulator species and hence an enabling large-scale implementation of agromining. This approach promotes a new form of agriculture, which could generate income for peoples in developing countries that live on agriculturally mediocre lands, such as those derived from ultramafic bedrock. Finally, the implication of scientific knowledge in the chain, such as chemistry and chemical engineering, and the stimulation of pluri-disciplinary research programs, bring hope to the feasibility of manufacturing specialist products of high industrial interest from agromined bio-ore.