The Deepwater Horizon (DWH) oil spill was the largest marine oil release to date in US waters, and ranks among the largest worldwide. Over 2,100 km of Gulf of Mexico shorelines were exposed to DWH oiling, with an unprecedented potential for environmental damage. Scores of individual studies and reports have described the impact of the DWH oil spill on wetland vegetation, soil and benthic organisms in the Gulf of Mexico, including over a dozen studies from the current proposal team. While results to date generally indicate that recovery is occurring but not yet complete, individual studies by themselves do not create a complete picture of DWH impacts, and in some cases findings and conclusions are unclear or contradictory. As such, a clear understanding of the ecosystem, community, and population effects can be difficult to discern, even for large spills such as the DWH. Hence, a synthesis of results is needed to provide a more comprehensive understanding of marsh degradation and recovery following the DWH spill. Therefore, the overall goal of this proposed research is to assess the long-term impacts of the DWH spill using a broader, collaborative approach that includes meta-analytic synthesis of results across multiple data sets such as data from GoMRI, the Natural Resource Damage Assessment (NRDA), as well as literature synthesis of numerous other published and unpublished studies.
Members of this project team have previously conducted similar meta-analyses and literature syntheses to evaluate DWH impacts and recovery for two groups of coastal wetland macroinvertebrates (fiddler crabs, Uca species and marsh periwinkles, Littoraria irrorata). In both cases, new, interesting, and more robust interpretations emerged from the analysis of multiple data sources across wider geographies and longer time frames, answering questions that could not be addressed by individual studies alone. This project proposes to further apply similar meta-analytic approaches to synthesize coastal wetland oiling impacts and recovery across a broader range of ecosystem response variables, such as coastal wetland plants, benthic macroinvertebrates and infauna, shoreline erosion, and soil-oil characteristics. Results across ecosystem components will also be integrated into an overall summary of impacts and recovery for the coastal wetland vegetation-soil-benthic complex, thus providing valuable information about the resiliency of coastal wetlands.
Overall, the results from this project will provide a more comprehensive understanding of the factors that control impacts, recovery, resilience, and sustainability of the wetland vegetation-soil-benthic complex. Results from this work will also inform current and future response, remediation, and restoration decisions for oiled coastal wetlands by providing integrated information of critical importance to understanding the pace of oil-spill recovery through data integration from various sources; scientific synthesis across themes; and overarching scientific products that exploit the scientific legacy GoMRI. In particular, this proposed research supports GoMRI Research Theme 3: environmental effects of spilled oil on wetlands, marshes, and organisms; and the science of ecosystem recovery, while also directly supporting the continuation of previously designated research themes and topics that have emerged through GoMRI.