Abstract
Submerged aquatic vegetation (SAV) in estuaries are known to provide many ecosystem services. However, anthropogenic stressors such as development, dredging, boat traffic, and excess nutrient loading are rapidly causing declines in SAV. The actions of waterfront property owners can directly lead to the impairment of SAV and consequently hamper many of the ecosystem services that attracted them to reside along the coast. Back Bay, Mississippi is poorly understood, but is known to have SAV beds that are dominated by Vallisneria americana. Additionally, over 60% of privately owned shorelines along the Bay are currently hardened with either a seawall, wooden, or vinyl bulkhead. To better understand the spatial extent of SAV in Back Bay and possible associations with shoreline type (e.g., hardened or natural), we collected high-resolution aerial imagery in October 2019 with a UAS around the entire perimeter of Back Bay, MS that was then processed and analyzed. Specifically, shorelines were classified as either hardened or natural and the distribution of SAV patches was mapped using the collected aerial imagery. The extent of SAV in Back Bay was found to be over 30 hectares with the majority of it clustered in the lower salinity western region of the Bay. Within that western region, identified natural and hardened shoreline segments were analyzed through ArcMap to determine the length of natural shorelines and bulkheads that included a patch of seagrass within 10 meters of the shore. Results showed that ~50% of the observed natural shorelines were associated with a seagrass patch within 10 meters while only ~23% of bulkheads had the same association. Further research is needed, but this work could suggest that the maintenance of natural shorelines supports SAV more effectively than hardened shorelines in Back Bay.
