Natural geological responses to anthropogenic alterations of the naples bay estuarine system

Abstract

The Naples Bay Estuarine System, situated in southwest Florida, has undergone extensive modifications caused directly and indirectly by anthropogenic influences. These alterations include the substitution of mangrove-forested shorelines with concrete bulkheads, canalization of the watershed and along the bay shoreline, and navigational channel dredging. The system consists of northern Naples Bay, southern Naples Bay, and Dollar Bay, whose shorelines range from highly developed to undeveloped, respectively. This project explored the natural geological response of the system to these alterations using data from side scan sonar, sediment grab samples, and vibracores. In highly urbanized northern Naples Bay, benthic substrates consist primarily of muddy sands, with few oyster reefs. Southern Naples Bay and Dollar Bay, however, consist of coarser sediment, and are characterized by extensive mangrove shorelines and numerous oyster reefs. The impact of anthropogenic alterations has significantly shifted sediment distributions in northern Naples Bay from a coarser to a finer grained substrate. This shift has occurred to a lesser degree in southern Naples Bay, and Dollar Bay has not made this transition, due to the relative lack of anthropogenic modifications made to this part of the system.