Impacts of the Deepwater Horizon oil spill on the salt marsh vegetation of Louisiana.
The coastal wetland vegetation component of the Deepwater Horizon oil spill Natural Resource Damage Assessment documented significant injury to the plant production and health of Louisiana salt marshes exposed to oiling. Specifically, marsh sites experiencing trace or greater vertical oiling of plant tissues displayed reductions in cover and peak standing crop relative to reference (no oiling), particularly in the marsh edge zone, for the majority of this four year study. Similarly, elevated chlorosis of plant tissue, as estimated by a vegetation health index, was detected for marsh sites with trace or greater vertical oiling in the first two years of the study. Key environmental factors, such as hydrologic regime, elevation, and soil characteristics, were generally similar across plant oiling classes (including reference), indicating that the observed injury to plant production and health was the result of plant oiling and not potential differences in environmental setting. Although fewer significant impacts to plant production and health were detected in the latter years of the study, this is due in part to decreased sample size occurring as a result of erosion (shoreline retreat) and resultant loss of plots, and should not be misconstrued as indicating full recovery of the ecosystem.
Institute for Coastal and Water Research, Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70504, USA. Electronic address: mhester@louisiana.edu.
Mark W
MW
Hester
Institute for Coastal and Water Research, Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70504, USA.
Jonathan M
JM
Willis
NewFields Companies, LLC, Atlanta, GA 30309, USA.
Shahrokh
S
Rouhani
National Oceanic and Atmospheric Administration, Assessment and Restoration Division, Seattle, WA 98115, USA.
Marla A
MA
Steinhoff
National Oceanic and Atmospheric Administration, Assessment and Restoration Division, Seattle, WA 98115, USA.
Mary C
MC
Baker
D003247:Conservation of Natural Resources; D017753:Ecosystem; D004784:Environmental Monitoring; D052918:Environmental Restoration and Remediation; D060851:Gulf of America; D008145:Louisiana; D059392:Petroleum Pollution / Q000032:analysis*; D010944:Plants / Q000187:drug effects*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry / Q000633:toxicity*; D053833:Wetlands
D014874:Water Pollutants, Chemical
Deepwater Horizon oil spill; Injury; Louisiana; NRDA; Salt marsh