Suitability of Miscanthus species for managing inorganic and organic contaminated land and restoring ecosystem services. A review
Résumé
The mitigation of potential health hazards and land scarcity due to land use change can be addressed by restoring functional and ecosystem services of contaminated land. Physico-chemical remediation options are criticized as being costly and not providing environment-friendly solutions. The use of plants and associated microorganisms could be a sustainable, cost-effective option to reduce pollutant exposure. Phytomanagement aims at using valuable non-food crops to alleviate environmental and health risks induced by pollutants, and at restoring ecosystem services. Suitable plant species must be tolerant to contaminants, reduce their transfer into the food chain, and efficiently produce marketable biomass. Based on Miscanthus' capacity to sequestrate inorganic contaminants into the root system and to induce dissipation of persistent organic contaminants in soil, these plant species are favorable for phytostabilization and phytodegradation. Among Miscanthus species, the noninvasive hybrid Miscanthus × giganteus, with a high lignocellulosic content, is a promising biomass crop for the bio-economy, notably the biorefinery and bioenergy industries. Planting this species on contaminated and marginal land is a promising option to avoid changes in arable land use to mitigate the food vs. biofuel controversy. Key issues in promoting sustainable management of Miscanthus sp. on contaminated land are: (a) crop suitability, integration, and sustainability in a region with a potential local market; (b) site suitability in relation to the species' requirements and potential, (c) biotic interactions in the landscape diversity; and (d) increase in shoot yields in line with various stressors (e.g., pollutants, drought, cold temperatures), and with minimal inputs.