DSTR 22 |
| Phospholipid fatty acids (PLFA) were analyzed for 11 sediment samples collected from New Orleans and Chalmette in September, 2005, following Hurricanes Katrina and Rita. The sediments deposited by the floodwaters from these events were elevated in PLFA biomass relative to stream sediment, ranging from 39 to 541 nmol fatty acid per dry gram sediment, reflecting the organic-rich depositional environments of Lake Pontchartrain and the coastal wetlands to the south. Principal components analysis showed two distinct groups among the downtown New Orleans samples, one group defined by greater mole percent of 16:1ω7c, a lipid biomarker for certain gram-negative bacteria, and 18:1ω9c, a biomarker for some fungi. Group 2 lacked these lipid biomarkers, but had greater mole percent of i15:0, a gram-positive bacterial biomarker. The Chalmette samples had similarities to both group 1 and 2. These results suggest multiple sources for sediments transported during post-hurricane flooding, including Lake Pontchartrain, canals, and wetlands. |
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Recovery from and Prevention of Natural Disasters
1:00 PM-5:05 PM, Tuesday, 12 September 2006 Moscone Center -- Room 300, Oral
Recovery From & Prevention of Natural Disasters |