By David Biello
(Click here for the original article.)
Microbes kept the oil and gas spewing from the Macondo well from becoming even more of a disaster, preventing the Deepwater Horizon blowout from deeply befouling the Gulf coast. But these hydrocarbon-chompers got an assist from the Gulf of Mexico -- the prevailing tides and currents helped keep hydrocarbon-eating microbes on the job, according to the results of a new model published in Proceedings of the National Academy of Sciences on January 9.
Simply put, the study sought to answer the question: how did five families of bacteria keep 4.1 million barrels of oil (and billions of cubic feet of natural gas) from becoming a bigger disaster? And, additionally, why didn’t they suck all the oxygen out of the water while they were at it?
The answer appears to be ocean currents, according to a computer model:
Water mixing ensured that the 200 billion grams of hydrocarbons injected into the Gulf of Mexico became, ultimately, some 100 sextillion microbial cells of propane- and ethane-consuming Colwellia, aromatic-eating Cycloclasticus, methane-munching Methylococcaceaa and alkane-eating Oceanospirillales. They also ensured that hydrocarbons were introduced into waters already hosting microbe blooms spurred by earlier oil and gas releases. The team of researchers suggest that this "autoinoculation" -- early blooms drifting back to the spill site and chowing down anew -- allowed the microbes to work fast over the course of the months-long disaster as well as keeping oxygen depletion from growing too severe in any one place.
The model isn't perfect -- it failed to precisely match observations of where the oil (and microbial) plume traveled -- but it does explain why oil and gas consumption can proceed so fast, even when it's microbes (and not humans) doing the hydrocarbon consuming.