Abstract
Environmental degradation related to mining-generated acid mine drainage (AMD) is a major global concern, contaminating surface and groundwater sources, including agricultural land. In the last two decades, many developing countries are expanding agricultural productivity in mine-impacted soils to meet food demand for their rapidly growing population. Further, the practice of AMD water (treated or untreated) irrigated agriculture is on the increase, particularly in water-stressed nations around the world. For sustainable agricultural production systems, optimal microbial diversity, and functioning is critical for soil health and plant productivity. Thus, this review presents up-to-date knowledge on the microbial structure and functional dynamics of AMD habitats and AMD-impacted agricultural soils. The long-term effects of AMD water such as soil acidification, heavy metals (HM), iron and sulfate pollution, greatly reduces microbial biomass, richness, and diversity, impairing soil health plant growth and productivity, and impacts food safety negatively. Despite these drawbacks, AMD-impacted habitats are unique ecological niches for novel acidophilic, HM, and sulfate-adapted microbial phylotypes that might be beneficial to optimal plant growth and productivity and bioremediation of polluted agricultural soils. This review has also highlighted the impact active and passive treatment technologies on AMD microbial diversity, further extending the discussion on the interrelated microbial diversity, and beneficial functions such as metal bioremediation, acidity neutralization, symbiotic rhizomicrobiome assembly, and plant growth promotion, sulfates/iron reduction, and biogeochemical N and C recycling under AMD-impacted environment. The significance of sulfur-reducing bacteria (SRB), iron-oxidizing bacteria (FeOB), and plant growth promoting rhizobacteria (PGPRs) as key players in many passive and active systems dedicated to bioremediation and microbe-assisted phytoremediation is also elucidated and discussed. Finally, new perspectives on the need for future studies, integrating meta-omics and process engineering on AMD-impacted microbiomes, key to designing and optimizing of robust active and passive bioremediation of AMD-water before application to agricultural production is proposed.
Highlights
Large-scale commercial mining operations and other related industries generate various waste streams, that constitute one of the major anthropogenic sources of environmental pollution
This review provides an overview of the microbial community structure and diversity of acid mine drainage (AMD) wastewater, highlighting the potential positive and negative roles associated microbiome may play under AMD-irrigated agricultural production
We focus on the prokaryotic structure and functioning providing a comprehensive assessment of the main implications and challenges of using untreated AMD wastewater for irrigated agricultural production
Summary
Large-scale commercial mining operations and other related industries generate various waste streams, that constitute one of the major anthropogenic sources of environmental pollution. Under the extremophilic AMD environment, acidophilic microbial communities belonging to Bacteria, Archaea, and Eukarya domains dominates, with members of phylum Proteobacteria, Nitrospira, Actinobacteria, Firmicutes, and Acidobacteria being the dominant bacterial taxa (Mesa et al, 2017; Lukhele et al, 2019; Distaso et al, 2020), as well as iron/sulfur-oxidizing microbes such Leptospirillum ferrooxidans, Ferrovum, Acidothiobacillus occurring in an environmentally dependent biogeographic pattern (Kuang et al, 2013, 2016; Wang et al, 2019b). There are excellent articles that has thoroughly reviewed AMD ecosystems as extreme habitats that provides multiple niches for distinct bacterial, archaeal, and eukaryotic microbiomes (Baker and Banfield, 2003; Méndez-García et al, 2015; Chen et al, 2016; Mesa et al, 2017; Lukhele et al, 2020) In these reports, the dominance of members of Eukarya domain, including fungal and algal taxa has been reported in diverse AMD sites across the globe (Baker et al, 2009). Passive bioremediation system enriched with Ignavibacterium, Pelotomaculum, and Petrimonas and species known to catalyse the dissimilatory reduction of ferric iron (Geobacter psychrophilus), oxidation of sulfur (Polaromonas hydrogenivorans, Flavobacterium johnsoniae, Dechloromonas aromatica, Novosphingobium sediminicola, Clostridium saccharobutylicum, and Pseudomonas extremaustralis), and reduction of nitrate
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
