Microbial Features Indicating the Recovery of Soil Ecosystem Strongly Affected by Mining and Ore Processing

Abstract

Tailings-derived soils formed from waste materials produced during mineral processing often exhibit extremes of pH, low content of organic matter and limited nutrient availability. The success of site revitalization depends mostly on the ability to maintain natural soil functions. We analyzed technogenic sediments from four selected localities in Slovakia defined as environmental burdens: Slovinky (SLS, SLD), Markušovce (MAS, MAD), Lintich (LIS, LID), Horná Ves (HVS, HVD) in the presented research. None of these sites has long been used for its original purpose. In all localities, the concentrations of several risk elements (As, Ba, Cd, Co, Cr, Cu, Ni, Pb, Zn) still significantly exceed the statutory limit values. Besides the content of risk elements, the amounts of organic carbon, total nitrogen, pH value and moisture level in technogenic substrates were determined. We evaluated selected microbiological parameters, including microbial biomass carbon (MBC), microbial respiration and cellulolytic activity to determine how soil organisms tolerate long-term pollution. In general, the values of microbiological parameters were not as low as one would expect. The results confirmed a negative correlation between MBC content and concentrations of several toxic metals (Co, Cr, Cu, Ni, Zn). The values of assessed microbial indicators were in several cases comparable to those in natural soils. We noticed the lowest metabolic quotient values (qCO2) in the heavily polluted locality HVS. The microbial quotient (qMic) was low in every locality except HVS, where the substrate availability index (SAI) was highest. The soil microbial community properties have shown that, despite adverse conditions, these emerging soils allow the growth and development of microorganisms to such an extent that they can adequately use available (although limited) nutrients. The data obtained suggest that these severely impacted soil ecosystems can restore their original environmental functions in time.

Effects of Phytoremediation on Microbial Biomass, Composition, and Function in a Sulphide-Rich Tailing From a Metal-Contaminated Region

“…Londry and Sherriff (2005) reported a significant correlation between microbial biomass and biodiversity with physicochemical conditions in mine tailing in Manitoba (Canada). Their findings were consistent with data reported by Feketeová et al (2021) investigating the recovery of soil ecosystem at tailings ponds affected by mining in Slovakia. Li et al (2018) on the other hand reported microbial diversity increases and high activities of microorganisms induced by applications of zinc, lead, and sulfidic copper in tailing areas in Australia.…”

Reclamation of abandoned magnesite site using amendments and plantation

“…The highest microbial N was found in sulfur + manure treatment in this study, which is one‐third lower than that Ng (2012) reported for a post‐lignite mining site in east Texas, with a mean of 70 μg C/g. Similarly, we found lower microbial C than Feketeová et al (2021) reported, with a value of 315 μg N/g. During open‐pit mining, the topsoil is stripped and stored for use in the restoration of the site after the activity has ceased.…”

Distinct Changes in Abundance of Culturable Microbial Community and Respiration Activities in Response to Mineral–Organic Mixture Application in Contaminated Soil

“…This correlation is consistent with the results obtained in this study. An interesting approach to the presence of soil microorganisms in polluted/post-industrial areas was presented in the study of Feketeova et al [60]. The quoted authors concluded that, in soils contaminated with heavy metals, microorganisms can utilize available nutrients very efficiently without unnecessary energy losses and without difficulties related to survival.…”