Characterization of microbial response to petroleum hydrocarbon contamination in a lacustrine ecosystem

Abstract

Microbiomes of freshwater basins intended for human use remain poorly studied, with very little known about the microbial response to in situ oil spills. Lake Pertusillo is an artificial freshwater reservoir in Basilicata, Italy, and serves as the primary source of drinking water for more than one and a half million people in the region. Notably, it is located in close proximity to one of the largest oil extraction plants in Europe. The lake suffered a major oil spill in 2017, where approximately 400 tons of crude oil spilled into the lake; importantly, the pollution event provided a rare opportunity to study how the lacustrine microbiome responds to petroleum hydrocarbon contamination. Water samples were collected from Lake Pertusillo 10 months prior to and 3 months after the accident. The presence of hydrocarbons was verified and the taxonomic and functional aspects of the lake microbiome were assessed. The analysis revealed specialized successional patterns of lake microbial communities that were potentially capable of degrading complex, recalcitrant hydrocarbons, including aromatic, chloroaromatic, nitroaromatic, and sulfur containing aromatic hydrocarbons. Our findings indicated that changes in the freshwater microbial community were associated with the oil pollution event, where microbial patterns identified in the lacustrine microbiome 3 months after the oil spill were representative of its hydrocarbonoclastic potential and may serve as effective proxies for lacustrine oil pollution.

Remote Sensing Detection of Algal Blooms in a Lake Impacted by Petroleum Hydrocarbons

“…In this study, the availability of Sentinel-2 satellite data made it possible to carry out retrospective studies. The images of hydrocarbon contamination highlighted with our satellite cold case analysis on 27 February, may represent the original event that gave rise to the formation of the hydrocarbonoclastic microbial community highlighted in our previous study [47]. Using metagenomics and metabolic reconstruction of the lake community, we showed that after 3 months (May 2017) from the oil spill event (27 February), the lake had high levels of Hydrogenophaga, Acidovorax, Reyranella, and Variovorax.…”

“…Sentinel-2A observations assessed ecosystem conditions, indicating a eutrophic status due to the effects of oil spills on algal populations. Furthermore, we previously carried out metagenomic studies on polluted samples from Lake Pertusillo which detected the presence of a hydrocarbonoclastic microbial community, thereby confirming the polluted state of the lake and indicating a model of a microbial community impacted by hydrocarbon pollution [47]. Collectively, these data demonstrate that satellite systems have the potential to detect natural contamination phenomena, such as algal blooms and anthropogenic pollution, as oil spills.…”

“…In May 2017, ENI publicly admitted a crude oil spill of more than 400 tons from the ENI Val d'Agri oil hub of Viggiano between August and November 2016. During 2017, civic associations and the Regional Agency for Environment Protection of Basilicata (ARPAB) performed analyses of lake waters for the determination of hydrocarbons and phytoplankton [45,46], following which metagenomic study of Lake Pertusillo identified a lake microbial community shaped by the presence of hydrocarbons [47]. The occurrence of several known hydrocarbon pollution events in combination with periodic algal blooms in Lake Pertusillo provided an opportunity to test new methods for high-frequency monitoring in untoward environmental incidents, which may further improve warning and remediation strategies.…”

Effect of deposit chemistry on microbial community structure and activity: Implications for under-deposit microbial corrosion

“…Microbial ecology research in the oil and gas industry has shown that shifts in microbial community structure and metabolic capabilities occur in response to changes in the environment, such as nitrate injection ( Vigneron et al, 2017 ), hydrocarbons presence ( D’Ugo et al, 2021 ), usage of mixed corrosion inhibitors ( Duncan et al, 2014 ). It is therefore plausible to assert that UDMC rates and mechanisms will differ when two chemically different types of sand-deposits are tested, mainly because of the impact that the sand-deposit chemistry would have in the microbial ecology dynamics.…”