Summary:
An integrated experimental and computational study is timely proposed to acquire the fundamental knowledge on the impact of crude oil on marsh erosion in southern Louisiana, home to America's largest wetlands, in wake of the recent BP Deepwater Horizon oil spill that transforms some wetlands into a rare, valuable, large-scale, oil-contaminated experimental site. A stable and healthy marsh provides the basic physical structure and foundation for the sustainability of coastal wetlands, the most productive ecosystem on Earth, which are also a protective buffer zone for hurricanes and storms.
The BP oil spill is an economic and environmental disaster. Now that it has happened, advantages should be taken of this accident (a rare and valuable opportunity) to study and assess every aspect of its possible influences and environmental damages. The majority of currently funded studies focus on its biological, chemical, or environmental impact, but not on the physical stability or erosion of coastal wetlands. This project is the first of its kind to study oil-contaminated marsh erosion and to further develop a predictive capability to assess the resiliency of the contaminated marshes under storm and hurricane conditions. The overall goal of this project is to study and understand the fundamental science of oil-contaminated coastal marsh erosion.
This goal will be achieved by three structured, mutually complementary objectives:
1. To acquire the first datasets on the erosion of coastal marshes with different degrees of oil contamination
2. To understand the physical and biogeochemical mechanisms controlling oil-contaminated marsh erosion via laboratory testing and computational modeling
3. To predict the resilience of the oil-contaminated marsh under storm and hurricane conditions
Collaborative research between a hurricane/wave modeling expert and a geotechnical experimentalist is proposed in three major areas:
A. Field measurements to acquire for the first time the erosion resistance and erosion rate of oil-contaminated coastal marsh, as well as wave measurement for subsequent modeling of erosion
B. Studying and understanding the science of oil-contaminated marsh erosion via laboratory characterization designed to uncover the underlying physical and biogeochemical mechanisms
C. Modeling marsh erosion using the obtained soil erosion resistance, vegetation data, and wave data, and predicting the resilience of contaminated wetlands under storm and hurricane conditions
The three areas of research are further subdivided into six tasks, consisting of field and laboratory testing, in-situ monitoring, and numerical modeling. Inter-institutional collaborations with the Dauphin Island Sea Lab and Mississippi State University are also proposed by sharing field measurement data, such as wave and marsh erosion data, and modeling expertise.
The project has its unique intellectual merit in the following aspects:
1. Acquiring the first datasets on the oil-contaminated marsh erosions and hence enhancing the knowledge base to be used for coastal protection and restoration
2. Uncovering the mechanisms of how crude oil interferes with the microbial activities (e.g., biofilm or EPS production) and hence natural cohesive soil erosion, which will lead to more studies on the evolved science of sediment-oil-biota interactions
3. Developing a predictive capability for coastal wetland protection and restoration