Research

Oil Spill Impacts on Coastal Wetlands

  

Along with colleagues from LSU, VIMS, RPI, and Atkins, I am currently involved in multifaceted research aimed at identifying the impacts of the Deepwater Horizon (DWH) oil spill on coastal wetlands and understanding the recovery pace of associated ecosystem structure, function, and stability. My lab is currently investigating the long-term effects of hydrocarbon stress on interacting salt marsh communities by (1) comparing relationships between Spartina alterniflora (smooth cordgrass) and Geukensia granosissima (southern ribbed mussels) in heavily oiled and reference marshes, and (2) conducting mussel density surveys across salt marsh sites exposed to varying degrees of oiling. My lab is also assessing the long-term impacts of the DWH spill on soil carbon stocks, as well as leading a broader, collaborative approach that includes meta-analytic synthesis of results across multiple data sets. Overall, the results from these projects will provide a more comprehensive understanding of the factors that control coastal wetland impacts, recovery, resilience, and sustainability following the oil spills.

Coastal Wetland Restoration

In order to offset continuing coastal wetland loss in the Mississippi River Delta, strategies are being developed to create and restore coastal marshes using a combination of Mississippi River diversions and hydraulic conveyance to deliver sediment.  Increasing the external supply of sediment is predicted to create a positive biophysical feedback that enhances the ability of coastal marshes to keep pace with sea-level rise. However, river diversions also introduce high nutrient loads into existing and newly created marshes, with potentially negative impacts. Along with colleagues at LSU, my lab is currently conducting research that will provide critical information on these effects using a multi-tiered approach that focuses on the restoration potential of brackish marshes in coastal Louisiana. The goal of this research is to identify how enhanced nutrient and sediment availability interact to influence coastal wetland nutrient cycling, plant productivity and biomass allocation, decomposition, and soil organic matter accumulation and accretion.

Coastal Wetland Eutrophication

Coastal wetlands are important regulators of near-shore water quality, but they are also vulnerable to excess nutrient loading from anthropogenic sources.  However, additional research is needed to understand how high nutrient loading impacts critical belowground processes that influence wetland functions and stability. My lab is currently conducting research that will continue two long-term marsh fertilization experiments, offering a rare opportunity to investigate nutrient enrichment effects on coastal wetlands over a multi-decade scale timeframe. This long-term research will not only provide a more comprehensive understanding of the effects of nutrient enrichment on coastal wetland sustainability, but will also lead to the development of more accurate predictions of the consequences of coastal wetland eutrophication, as well as the strategies to mitigate against any potential losses of important ecological and economic services caused by wetland degradation.

Wetland Ecologist