eDNA
Analysis of Aquatic Microcosms Reveals the Effects of a Copper Pollution Event on Sedimentary Microbial Assemblages in Freshwater Wetlands
Anna S. Flynn, A. Mark Osborn, Vincent Pettigrove, Jeff Shimeta, Sara M. Long ABSTRACT
Metal contamination is known to cause shifts in structure of freshwater assemblages where sensitive species do not survive and tolerant species thrive, and given their sensitivity, ubiquitous nature, and high abundances, microbes are ideal targets for biomonitoring assessments. However, the responses of diverse microbial communities to metal contamination in freshwater environments are currently understudied, particularly in the Southern hemisphere. Therefore, in this study we used environmental DNA metabarcoding to assess the influence of copper contamination events on an urban wetland. Laboratory‐based microcosms with clean and contaminated sediments were spiked with copper sulphate to assess microbial responses. We saw significant microbial variation both over time and between concentrations, with responses varying between the microbes from uncontaminated and contaminated sediments; outlining how the dynamics develop over a concentration and temporal gradient and how they vary with assemblages from contaminated and uncontaminated environments, with seven families identified as possible indicators of metal contamination.