title: Microbially-driven strategies for bioremediation of bauxite residue.
abstract: Globally, 3 Gt of bauxite residue is currently in storage, with an additional 120 Mt generated every year. Bauxite residue is an alkaline, saline, sodic, massive, and fine grained material with little organic carbon or plant nutrients. To date, remediation of bauxite residue has focused on the use of chemical and physical amendments to address high pH, high salinity, and poor drainage and aeration. No studies to date have evaluated the potential for microbial communities to contribute to remediation as part of a combined approach integrating chemical, physical, and biological amendments. This review considers natural alkaline, saline environments that present similar challenges for microbial survival and evaluates candidate microorganisms that are both adapted for survival in these environments and have the capacity to carry out beneficial metabolisms in bauxite residue. Fermentation, sulfur oxidation, and extracellular polymeric substance production emerge as promising pathways for bioremediation whether employed individually or in combination. A combination of bioaugmentation (addition of inocula from other alkaline, saline environments) and biostimulation (addition of nutrients to promote microbial growth and activity) of the native community in bauxite residue is recommended as the approach most likely to be successful in promoting bioremediation of bauxite residue.
authors: Centre for Mined Land Rehabilitation, Sir James Foots Building, The University of Queensland, St. Lucia, QLD 4072, Australia; School of Geography, Planning, and Environmental Management, Steele Building, The University of Queensland, St. Lucia, QLD 4072, Australia; School of Earth and Environment, The University of Western Australia, 35 Stirling Hwy Crawley, WA 6009, Australia. Electronic address: t.santini@uq.edu.au.
authors: Talitha C
authors: TC
authors: Santini
authors: Centre for Mined Land Rehabilitation, Sir James Foots Building, The University of Queensland, St. Lucia, QLD 4072, Australia.
authors: Janice L
authors: JL
authors: Kerr
authors: School of Geography and Earth Sciences, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada.
authors: Lesley A
authors: LA
authors: Warren
mesh_terms: D000537:Aluminum Oxide; D001673:Biodegradation, Environmental; D007220:Industrial Waste; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D007220:Industrial Waste; D012989:Soil Pollutants; D000537:Aluminum Oxide
keywords: Bauxite residue; Bioaugmentation; Bioremediation; Biostimulation; Geomicrobiology