GEOMORPHOLOGICAL RESPONSES OF THE BILOXI MARSH PLATFORMS DUE TO THE VARYING VOLUME AND DISTRIBUTION OF MARSH-EDGE SHELL RIDGES DURING COLD FRONT AND TROPICAL STORM SEASONS

Wetlands in coastal Louisiana account for 37% of total wetlands in the United States, yet account for 90% of the total wetland loss. Recent research shows the percent of Louisiana’s coastal wetland loss is decreasing, likely due to the lack of major hurricanes since 2008. The study area, Biloxi marsh, is located south of Lake Borgne and was formed by progradation of the St. Bernard delta complex. One unique geomorphologic feature of Biloxi marsh is the presence of oyster and clam shells, which wash onto the marsh platform and create shell ridges. Crassotrea virginica is the most common shell found in the area. Shell ridges can act as a buffer against erosion when immobile or suffocate marsh vegetation when mobile. Suffocation of vegetation can lead to the destabilization of the marsh platform. The proposed work will build off of existing work, examining how the ridges have changed through time. Historic land loss data will be compared to total volume, length, and distribution of shell ridges to analyze if there is a trend, such as the presence of historic storm activity. One hypothesis is that intervals of heightened tropical storm activity will have a direct correlation to the increasing volume and distribution of shell ridges throughout Biloxi marsh. With this information the city of New Orleans and state of Louisiana will have a better understanding of the life expectancy of Biloxi marsh as it is the main buffer against storms.