The Effect of Heavy Metals on Microbial Communities in Industrial Soil in the Area of Piekary Śląskie and Bukowno (Poland)

Abstract

The aim of this study was to determine the activity and structure of microbial communities in soils contaminated with heavy metals (HMs). To achieve this goal, soil samples were taken from two contaminated sites (i.e., Piekary Śląskie and Bukowno) in Poland. A wide range of methods were applied, including: total and metal-tolerant culturable bacteria enumeration; microbial community structure analysis using the phospholipid fatty acid method (PLFA); denaturing gradient gel electrophoresis (PCR-DGGE); and metabolic activity using BIOLOG and EcoPlateTM. Our studies showed that HMs negatively affected microbial community structure and activity in polluted soils. Apart from the contamination with HMs, other soil parameters like soil pH and water also impacted microbial community structure and growth. Metal-tolerant bacterial strains were isolated, identified and tested for presence of genes encoding HM tolerance using the polymerase chain reaction (PCR) methodology. Contamination with HMs in the tested areas was found to lead to development of metallotolerant bacteria with multiple tolerances toward Zn, Ni, Cd and Cu. Different genes (e.g., czcA, cadA and nccA) encoding HM efflux pumps were detected within isolated bacteria. Culturable bacteria isolated belonged to Proteobacteria, Actinobacteria and Bacteroidetes genera. Among non-culturable bacteria in soil samples, a significant fraction of the total bacteria and phyla, such as Gemmatimonadetes and Acidobacteria, were found to be present in all studied soils. In addition, bacteria of the Chloroflexi genus was present in soil samples from Piekary Śląskie, while bacteria of the Firmicutes genus were found in soil samples from Bukowno.

Sensitivity of Pathogenic Bacteria Strains to Treated Mine Water

“…In addition to the above-mentioned environmental issues, mining activities, active or closed, are producing and have left significant ecological footprints and negative impacts on the environment, such as open pits, underground workings, tailings heaps containing high quantities of chemical compounds (including heavy metals, sulfides and polysulfides) and metals being leached and released in the mine water as metal sulfates, with harmful effects on receiving ecosystems, aquatic organisms and implicitly human health [ 4 , 5 , 6 ]. The acidity, heavy metals and metalloids are considered as the main contributors of the mine water’s toxicity, inhibiting the system metabolism, disturbing of carbon, nitrogen and organic matter cycles and reducing the microorganism biodiversity [ 7 , 8 ]. However, van Dam et al, 2014 [ 9 ] emphasized that in the absence of elevated concentrations of toxic trace metals, the major ions (or salinity) are a key source to a mine water’s toxicity, mostly due to osmotic stress [ 9 ].…”

The inevitability of arbuscular mycorrhiza for sustainability in organic agriculture—A critical review

“…Continuous use of such contaminated chemical fertilizers in the field can lead to a gradual accumulation of metals in the soil over years of usage (Adhikari et al, 2021). In general, toxic heavy metals affect soil health by directly influencing the microbial flora of the soil and soil structure (Chu, 2018;Jarosławiecka and Piotrowska-Seget, 2022).…”

Effect of Soil Application of Zeolite-Carbon Composite, Leonardite and Lignite on the Microorganisms

“…Their presence determines the biological activity of the soil as well as soil-forming processes. Azotobacter, ammonifiers, and actinomycetes are often defined as indicators of soil fertility [1,[5][6][7][8][9]. With their ability to bind atmospheric nitrogen and convert it into ammonia, Azotobacter spp.…”

“…Azotobacter spp. are therefore functionally important free-living bacteria that fix atmospheric nitrogen, since their presence affects soil fertility and thus enhances plant growth [7]. Actinomycetes, which belong to Gram-positive bacteria, are commonly found in soil, composts, water, and bottom sediments.…”