Effects of diurnal temperature variation on microbial community and petroleum hydrocarbon biodegradation in contaminated soils from a sub‐ Arctic site

• Published in: Environmental Microbiology
• Main Authors: Akbari, Ali, Ghoshal, Subhasis
• Other Authors: Imperial Oil Ltd., Natural Science and Engineering Research Council (NSERC)
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2015
• Subjects: Arctic
• Online Access: http://dx.doi.org/10.1111/1462-2920.12846; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2F1462-2920.12846; http://onlinelibrary.wiley.com/wol1/doi/10.1111/1462-2920.12846/fullpdf

Summary Contaminated soils are subject to diurnal and seasonal temperature variations during on‐site ex‐situ bioremediation processes. We assessed how diurnal temperature variations similar to that in summer at the site from which petroleum hydrocarbon‐contaminated soil was collected affect the soil microbial community and the extent of biodegradation of petroleum hydrocarbons compared with constant temperature regimes. Microbial community analyses for 16 S rRNA and alkB genes by pyrosequencing indicated that the microbial community for soils incubated under diurnal temperature variation from 5°C to 15°C ( VART 5‐15) evolved similarly to that for soils incubated at constant temperature of 15°C ( CST 15). In contrast, under a constant temperature of 5°C ( CST 5), the community evolved significantly different. The extent of biodegradation of C 10– C 16 hydrocarbons in the VART 5‐15 systems was 48%, comparable with the 41% biodegradation in CST 15 systems, but significantly higher than CST 5 systems at 11%. The enrichment of G ammaproteobacteria was observed in the alkB gene‐harbouring communities in VART 5‐15 and CST 15 but not in CST 5 systems. However, the A ctinobacteria was abundant at all temperature regimes. The results suggest that changes in microbial community composition as a result of diurnal temperature variations can significantly influence petroleum hydrocarbon bioremediation performance in cold regions.