Evaluation of Microbial Community Activity, Abundance and Structure in a Semiarid Soil Under Cadmium Pollution at Laboratory Level

Abstract

Cadmium (Cd) pollution can alter soil flora and fauna, as well as the microbial community associated with the main biogeochemical cycles of a soil. The present study was conducted to investigate the effect of two different concentrations of Cd pollutant, 6.5 mg kg −1 (low level) and 12.5 mg kg −1 (high level) on microbial community activity, abundance, and structure in a semiarid soil after a 60-day incubation period at laboratory level. Available Cd, water soluble carbon (WSC), microbial biomass carbon (C mic ), adenosine triphosphate (ATP) content, and real-time polymerase chain reaction were used to measure the influence of Cd on the abundance and activity of the microbial community. Bacteria and fungi community structure and diversity based on denaturing gradient gel electrophoresis (DGGE) analysis were also analyzed. The percentage of Cd extracted by diethylenetriamine pentaacetic acid increased with the higher total concentration of Cd added to the soil, being 16.9% at low level and 77.9% at the high level. WSC, C mic , and ATP content decreased significantly as soil Cd concentration increased (WSC 29% and 34%, C mic 27% and 35%, and ATP 32% and 47%, at low and high levels, respectively). While fungal diversity already decreased with low levels of Cd concentration, and was even more negatively affected by the higher pollution levels, bacterial (acidobacteria, α-proteobacteria, and β proteobacteria) diversity only showed a decline with the higher Cd concentration. The fungi-to-bacteria ratio showed by the different treatments could imply that fungi abundance is less influenced by increased Cd pollution, although fungi diversity as revealed by DGGE analysis diminished as soil Cd concentration increased.

Validation and Application of a PCR Primer Set to Quantify Fungal Communities in the Soil Environment by Real-Time Quantitative PCR

“…No Nuclearia sequences were detected in the clones, conversely to what was expected from the in silico analysis. This is in agreement with other studies involving this primer set in which only fungal sequences were detected [30] , [33] , [35] , [42] and may be related to a relatively low abundance of Nuclearia (only 9 taxa recorded in the Genbank database).…”

Spatial Variation in Microbial Community in Response to As and Pb Contamination in Paddy Soils Near a Pb-Zn Mining Site

“…Molecular techniques such as high-throughput sequencing techniques have been used to evaluate the changes in microbial community due to HMs pollution (Ros et al, 2009;Gołębiewski et al, 2014). Changes in soil microbial community structure and diversity could serve as biomarkers to study the effect of HMs on soil health (Vinhal-Freitas et al, 2017;Li et al, 2020b;Di Cesare et al, 2020).…”

Illumina MiSeq sequencing investigation on the contrasting soil bacterial community structures in different iron mining areas

“…Berg observed that the relative abundance of bacterial groups changed within a Cu gradient (20 to 3537 mg/kg), which originated from CuSO 4 contamination over 85 years ago (Berg et al 2012). Margarita discussed the diversity of taxonomic groups after a 60-day incubation period with Cd concentrations reaching 12.5 mg/kg (Ros et al 2009). However, these previous studies ignored the ubiquitous mild heavy metal pollution effect on soil microbes, which was apparent in the iron mine in our studies.…”