Previously Unknown Species of Deep Water Bacteria Rapidly Degrading Oil in Gulf of Mexico
The oil spilled into the Gulf of Mexico is being degraded more rapidly than expected and without a precipitous decrease in oxygen levels. Those are among the fascinating findings in "Deep-Sea Oil Plume Enriches Indigenous Oil-Degrading Bacteria " just published in Science. An excellent write up can be found at the Berkeley Lab press center under "Study Shows Deepwater Oil Plume in Gulf Degraded by Microbes".
The essence of the findings are summarized in the release as follows:
"Hazen and his colleagues attribute the faster than expected rates of oil biodegradation at the 5 degrees Celsius temperature in part to the nature of Gulf light crude, which contains a large volatile component that is more biodegradable. The use of the COREXIT dispersant may have also accelerated biodegradation because of the small size of the oil particles and the low overall concentrations of oil in the plume. In addition, frequent episodic oil leaks from natural seeps in the Gulf seabed may have led to adaptations over long periods of time by the deep-sea microbial community that speed up hydrocarbon degradation rates.
One of the concerns raised about microbial degradation of the oil in a deepwater plume is that the microbes would also be consuming large portions of oxygen in the plume, creating so-called “dead-zones” in the water column where life cannot be sustained. In their study, the Berkeley Lab researchers found that oxygen saturation outside the plume was 67-percent while within the plume it was 59-percent"
