TY - JOUR
T1 - Long-term patterns of hydrocarbon biodegradation and bacterial community composition in epipelagic and mesopelagic zones of an Arctic fjord
AU - Kampouris, Ioannis D.
AU - Gründger, Grundger Friederike
AU - Christensen, Jan H.
AU - Greer, Charles W.
AU - Kjeldsen, Kasper Urup
AU - Boone, Wieter
AU - Meire, Lorenz
AU - Rysgaard, Søren
AU - Vergeynst, Leendert
N1 - Funding Information:
This work is a contribution to the Arctic Science Partnership (asp-net.org) and was supported by the research grant 17454 from Villum Fonden (Denmark) and the Multi-Partner Oil Spill Research Initiative (MPRI) of Fisheries and Oceans Canada .
Publisher Copyright:
© 2023 Elsevier B.V.
PY - 2023/3
Y1 - 2023/3
N2 - Oil spill attenuation in Arctic marine environments depends on oil-degrading bacteria. However, the seasonally harsh conditions in the Arctic such as nutrient limitations and sub-zero temperatures limit the activity even for bacteria capable of hydrocarbon metabolism at low temperatures. Here, we investigated whether the variance between epipelagic (seasonal temperature and inorganic nutrient variations) and mesopelagic zone (stable environmental conditions) could limit the growth of oil-degrading bacteria and lead to lower oil biodegradation rates in the epipelagic than in the mesopelagic zone. Therefore, we deployed absorbents coated with three oil types in a SW-Greenland fjord system at 10–20 m (epipelagic) and 615–650 m (mesopelagic) water depth for one year. During this period we monitored the development and succession of the bacterial biofilms colonizing the oil films by 16S rRNA gene amplicon quantification and sequencing, and the progression of oil biodegradation by gas chromatography – mass spectrometry oil fingerprinting analysis. The removal of hydrocarbons was significantly different, with several polycyclic aromatic hydrocarbons showing longer half-life times in the epipelagic than in the mesopelagic zone. Bacterial community composition and density (16S rRNA genes/ cm2) significantly differed between the two zones, with total bacteria reaching to log-fold higher densities (16S rRNA genes/cm2) in the mesopelagic than epipelagic oil-coated absorbents. Consequently, the environmental conditions in the epipelagic zone limited oil biodegradation performance by limiting bacterial growth.
AB - Oil spill attenuation in Arctic marine environments depends on oil-degrading bacteria. However, the seasonally harsh conditions in the Arctic such as nutrient limitations and sub-zero temperatures limit the activity even for bacteria capable of hydrocarbon metabolism at low temperatures. Here, we investigated whether the variance between epipelagic (seasonal temperature and inorganic nutrient variations) and mesopelagic zone (stable environmental conditions) could limit the growth of oil-degrading bacteria and lead to lower oil biodegradation rates in the epipelagic than in the mesopelagic zone. Therefore, we deployed absorbents coated with three oil types in a SW-Greenland fjord system at 10–20 m (epipelagic) and 615–650 m (mesopelagic) water depth for one year. During this period we monitored the development and succession of the bacterial biofilms colonizing the oil films by 16S rRNA gene amplicon quantification and sequencing, and the progression of oil biodegradation by gas chromatography – mass spectrometry oil fingerprinting analysis. The removal of hydrocarbons was significantly different, with several polycyclic aromatic hydrocarbons showing longer half-life times in the epipelagic than in the mesopelagic zone. Bacterial community composition and density (16S rRNA genes/ cm2) significantly differed between the two zones, with total bacteria reaching to log-fold higher densities (16S rRNA genes/cm2) in the mesopelagic than epipelagic oil-coated absorbents. Consequently, the environmental conditions in the epipelagic zone limited oil biodegradation performance by limiting bacterial growth.
KW - Arctic
KW - Microbiome
KW - Oil biodegradation
KW - Oil-degrading bacteria
UR - http://www.scopus.com/inward/record.url?scp=85146026657&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2022.130656
DO - 10.1016/j.jhazmat.2022.130656
M3 - Journal article
C2 - 36603421
AN - SCOPUS:85146026657
SN - 0304-3894
VL - 446
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
M1 - 130656
ER -