NCCOS Project Explorer (NPE)

Evaluation and Forecasting of Estuarine Shoreline Stabilization Techniques on Habitat Quality(2007)

Project Description:
he purpose of the proposed research is to evaluate the ecosystem structure and function of several shoreline types, including natural salt marsh with and without oyster reef, as well as shorelines stabilized with seawalls or stone breakwaters. We will measure whether erosion or accretion rates of sediments at each of these shoreline types, and measure ecologicial features such as plant species composition and density and fishery utilization. We will provide a preliminary tool for evaluating the physical setting of a structure under both natural and human sources of wave exposure. Specific (null) hypotheses addressed by the proposed work include: 1. There is no significant difference in the accretion or erosion of sediment in the intertidal zone among the following shoreline types; natural salt marsh, salt marsh fronted by oyster reef, marsh with offshore stone sill, salt marshes fronting vertical bulkheads. 2. Structural aspects of essential fishery habitat are not affected by shoreline stabilization structures. 3. Sediment characteristics, including organic matter content and grain size, are not affected by shoreline stabilization structures. 4. The effect of natural wave and boat wake wave climates on #1-3 does not vary between natural marsh shorelines and those stabilized with offshore stone breakwaters or vertical bulkheads. The ultimate goal of the work is to provide data that will enable us to predict both the effectiveness of the various shoreline types in preventing erosion, measure the impacts on estuarine habitat from constructing bulkheads or stone sills on existing natural shorelines, and evaluate the ability of fringing marshes to respond to sealevel rise.

Expected Outcome:
The proposed research will provide information to resource managers on the following issues relevant to estuarine ecosystems: 1. Understand climatic effects on species distribution and restoration success (ability of shoreline types to keep up with sea level rise) 2. Identify new and enhance existing nearshore/intertidal marsh restoration techniques 3. Identify new and enhance existing shellfish/oyster habitat restoration techniques 4. Identify, evaluate, and monitor sources and effects of anthropogenically-caused sediment erosion on pristine and/or restored habitats