This study investigated the main and interactive effects of nearshore breakwaters and marsh vegetation on faunal abundance and diversity along an eroded shoreline in Bon Secour Bay, Alabama. In summer 2016, eight replicates of three vegetation treatments plots (naturally vegetated, planted, and open) were established along a breakwater-protected and an adjacent no breakwater shoreline. After which, three methods were used to evaluate nekton quarterly from summer 2016 to summer 2018; Breder traps along the shoreline and lift nets and trawls in nearshore waters. Data were analyzed using the Shannon-Weiner diversity index and ANOVA. Results showed breakwaters supported significantly more abundant and diverse communities along the shoreline and in parallel nearshore waters than similar no breakwater sites. However, the main vegetation treatment effects were not significant. These findings suggest that living shoreline projects with nearshore breakwater support can be beneficial for fisheries enhancement in high-wave energy environments.

The research, presented here, is about the collaborative governance and adaptive management in coastal planning efforts of Louisiana. Fundamental conflict, between the idea of environmental conservation and developmental growth, has always existed in the coastal regions. The presence of the large number of environmental laws, at various levels of government and their different management objectives for utilization of coastal resources, requires study of intergovernmental relationship. Taking Plaquemines Parish as a case in point, this thesis will, therefore, review the critical restoration plans for intergovernmental coordination and conflicts. It will also provide recommendations, for elected representatives and policy makers, with an aim to promote collaborative governance and improve adaptive management of coastal resources.

The Louisiana Gulf Coast is a dynamic system of heavy influence on the cultures that live and prosper around it. Land in this area is in jeopardy of being lost. In 2017, the Coastal Protection and Restoration agency will issue a new State Master and this thesis provides a more intricate way of numerically predicting the behaviors of associated sediments. A model for the estimation of resuspension and deposition is proposed and prepared for integration into the existing model. The silt and clay fractions of the bed sediment and the sediment inflow were modeled by the widely used hydrodynamic models of Delft3D and ECOMSED, using the Young and Verhagen wave properties to obtain orbital velocities and bed shear stress. The critical shear stress for erosion was based on empirical formulas developed by van Rijn.

Open-coast beach-dune environments are vulnerable to erosion, such as from storms or interruption of littoral drift. Although protected from event-driven wave energy, backbarrier shorelines are also susceptible to erosion, due to tidal currents and boat wakes. A common response to mitigate erosion is to place sediment and restore the environment. For placement on beaches, a significant effort has been made to identify offshore resources available; however, offshore resources have seldom been considered for dune or backbarrier shoreline restoration. This study evaluates the geotechnical sediment properties of offshore sediments in proven borrow areas for beach nourishment and reclassifies them for placement in dunes and along the backbarrier in Palm Beach County, Florida. Two different methods calculate volume of offshore resources available for dune or backbarrier projects, including numerical calculations and interpolation of volume through SURFER. Because existing proven borrow areas are delineated for beach nourishment, less volume of sediment available in these areas for other coastal environments. The results of this study suggest that identifying offshore sediment sources for lower-energy environments would not adversely impact sediment needed for beach nourishment. As coastal environments are increasingly threatened by climate change and sea level rise, sediment resources become scarcer, the need to efficiently and effectively use sediments will be of utmost importance for scientists, engineers, and managers in their efforts to protect coastal habitat and communities. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection

To combat the rapid degradation of the Louisiana coast, the Louisiana Coastal Protection and Restoration Authority has planned strategic land building initiatives throughout the Louisiana Gulf coast, including beach nourishment and marsh creation projects. It is commonly agreed that the state lacks sufficient renewable sediment resources to maintain the planned CPRA land building program. However, Louisiana, the state that commonly ranks last in state recycling percentage, recycles an estimated 0.6% of the waste glass consumed in the state. Glass is predominantly silica sand. This thesis evaluates laboratory‑determined characteristics of recycled crushed glass cullet to assess its suitability as a renewable aggregate for beach nourishment and marsh creation projects. Specifically, the research herein evaluates geotechnical and settling characteristics of recycled crushed glass cullet produced in Pearl River, Louisiana. Additionally, this research evaluates the effects on beach nourishment and marsh creation design parameters of blending this material with Gulf coastal sediments.