Bacterial communities in mining soils and surrounding areas under regeneration process in a former ore mine

Abstract

Human activities on the Earth's surface change the landscape of natural ecosystems. Mining practices are one of the most severe human activities, drastically altering the chemical, physical and biological properties of the soil environment. Bacterial communities in soil play an important role in the maintenance of ecological relationships. This work shows bacterial diversity, metabolic repertoire and physiological behavior in five ecosystems samples with different levels of impact. These ecosystems belong to a historical area in Iron Quadrangle, Minas Gerais, Brazil, which suffered mining activities until its total depletion without recovery since today. The results revealed Proteobacteria as the most predominant phylum followed by Acidobacteria, Verrucomicrobia, Planctomycetes, and Bacteroidetes. Soils that have not undergone anthropological actions exhibit an increase ability to degrade carbon sources. The richest soil with the high diversity was found in ecosystems that have suffered anthropogenic action. Our study shows profile of diversity inferring metabolic profile, which may elucidate the mechanisms underlying changes in community structure in situ mining sites in Brazil. Our data comes from contributing to know the bacterial diversity, relationship between these bacteria and can explore strategies for natural bioremediation in mining areas or adjacent areas under regeneration process in iron mining areas.

Soil Yeast Communities in Revegetated Post-Mining and Adjacent Native Areas in Central Brazil

“…This finding confirms our hypothesis that the modification of the vegetation affects the composition of soil yeast communities, i.e., increased species richness in the Revegetated area following the secondary succession caused by mining activity (e.g., removal of native vegetation covers and revegetation with grasses). Higher species richness in the Revegetated area corroborates the results found for different functional groups of soil microorganisms in the iron-mining area of Brazil [ 13 , 20 , 21 , 22 , 23 ], including yeasts [ 24 ]. Our results are consistent with those reported for an area in the Brazilian Amazon rainforest, where the diversity of the soil microbial community increased after a deforestation event and forest conversion into permanent agricultural land [ 40 ].…”

“…The yeast community in this area was composed of six genera, and Saitozyma podzolica , a typical pedobiont species, was the most common species. As noted for the other soil functional groups [ 13 , 20 , 21 , 22 ], yeast communities were more diverse in disturbed ecosystems at iron mining sites than in natural ecosystems. These reports provide evidence on the role of soil yeasts, with other soil functional groups, in the recovery of degraded lands.…”

“…The bacterial community was more diverse at an environmental recovery mining site. Proteobacteria represented the predominant phylum [ 20 ], and a greater genetic diversity of nitrogen-fixing bacteria was found in the rehabilitated area that had been revegetated with grass [ 21 ]. Arbuscular mycorrhizal fungal communities were more diverse in revegetated sites than in the adjacent original ecosystems [ 13 , 22 ].…”

Microbiomes of different ages in Rendzic Leptosols in the Crimean Peninsula

“…Bacteroidetes are oligotrophs ( Fierer, Bradford & Jackson, 2007 ). Representatives within this phylum, Chitinophagaceae in particular, are essential for carbon decomposition, especially in sandy, loamy soils ( Ho et al, 2017 ; Fernandes et al, 2018 ). Consistent with this data, Bacteroidetes were more abundant in the lower nutrient soils of K2 and K3 sites.…”

Soil Bacterial Community and Soil Enzyme Activity Depending on the Cultivation of Triticum aestivum, Brassica napus, and Pisum sativum ssp. arvense

“…According to Maron et al [67], diminished diversity of microorganisms retards the degradation of both autochthonous and allochthonous carbon sources, thereby reducing the global emission of CO 2 by as much as 40%, whereas the importance of the diversity effect increases along with increasing the availability of nutrients. Bacteria from various families differ significantly in their genetics, which determine their functions in the soil environment [81]. For instance, bacteria representing the families Solibacteraceae and Acidobacteriaceae play an active part in protein and carbohydrate mineralization; those from the family Baciliaceae degrade chitin and cellulose, and participate in the biosynthesis of plant growth hormones and secondary metabolites [82]; bacteria from the family Burkholderiaceae are active participants of bioplastics biodegradation [83]; and Streptomycetaceae, Pseudonocardiaceae, and Promicromonosporaceae exhibit robust activity against carboxymethyl cellulose, xylan, chitin, and pectin substrates [84].…”