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WASHINGTON, Sept 24 (Reuters) - The muddy deep-sea ecosystemaround the massive 2010 Gulf of Mexico oil spill could takedecades to recover from the effects of the disaster, researchersreported on Tuesday.
The oil spill from BP Plc's Macondo well had its mostsevere impact on the ecosystem in an area about nine squaremiles (24 square km) around the wellhead, the report in theonline scientific journal PLoS One said.
Moderate effects were seen at 57 square miles (148 squarekm). The sea bottom's rich biodiversity was greatly reduced bythe oil plume, which was up to 200 yards (183 meters) thick and1.2 miles (1.9 km) wide, it said.
"Given deep-sea conditions, it is possible that recovery ofdeep-sea soft-bottom habitat and the associated communities inthe vicinity of the DWH blowout will take decades or longer,"the report concluded.
The April 20, 2010 disaster aboard the Deepwater Horizondrilling rig killed 11 workers and ruptured the Macondo well,triggering the worst offshore oil spill in U.S. history.
The research was carried out for the National Oceanic andAtmospheric Administration. Paul Montagna, an ecosystemsprofessor at Texas A&M University, said on NOAA's website thatnormally pollution was found within 300 to 600 yards (meters) ofan offshore well.
In the Macondo case, it was found nearly two miles (3.2 km)from the well, he said.
Jeff Baguley, an expert on tiny marine and freshwaterinvertebrates from the University of Nevada, said on the NOAAwebsite that the samples showed that the dominant group inaffected areas had become nematode worms.
The research team included members from University ofNevada-Reno, Texas A&M, NOAA's National Centers for CoastalOcean Science and representatives from BP.
