Figure 1.
(A) Map of Point Aux Pins peninsula. Study site indicated by box in inset. (B) Sediment samples collected ∼25 m from shore outside the marsh stands (designated “Inlet”) and 2–4 m from shore within the marsh stands (designated “Marsh”).
Table 1.
Point Aux Pins salt marsh inlet water column physical and chemical parameters.
Table 2.
Total petroleum hydrocarbons (TPH) detected in one or replicate samples.
Figure 2.
Boxplots of TPH concentrations in (a) Inlet and (b) Marsh surface and subsurface sediments.
Each box represents the concentration range of 50% of the observations. Lines within the boxes represent the median values, open squares are the averages, and the whisker lines connect to outliers.
Figure 3.
GCMS analysis of MC252 oil and oil-contaminated sediment.
(A) GCMS chromatogram of 10 ppm Macondo oil (MC252); (B) concentrations of n-alkanes in tar balls and sediment from July Marsh samples as determined by GCMS.
Table 3.
Number of bacterial OTUs detected by PhyloChip in Inlet and Marsh sediments for June, July, and September 2010.
Table 4.
Relative abundance (%) of families of Actinobacteria, Bacteroidetes, and Firmicutes known to contain hydrocarbon-degrading species.
Table 5.
Relative abundance (%) of families of Proteobacteria known to contain hydrocarbon-degrading species.
Figure 4.
Non-metric multi-dimensional scaling (nMDS) ordination of the bacterial community in salt marsh sediments.
Resemblance matrix generated using Bray Curtis similarity and based on the relative abundance of taxa identified by PhyloChip analysis.
Figure 5.
Relative abundance of phyla in salt marsh sediments.
Groups I, II, and III determined from nMDS analysis.
Figure 6.
Functional gene distribution in Inlet and Marsh sediments.
Gene relative abundance determined by GeoChip for samples compared between June and July 2010. Categories with significant changes indicated by *for p<0.05.
Figure 7.
Hydrocarbon degradation genes in Inlet sediments.
Average abundances of hydrocarbon degradation genes in Inlet sediments compared between June and July. Significant changes indicated by *for p<0.05 and **for p<0.01.
Figure 8.
Hydrocarbon degradation genes in Marsh sediments.
Average abundances of hydrocarbon degradation genes in Marsh sediments compared between June and July. Significant changes indicated by *for p<0.05 and **for p<0.01.