Sphaeroma terebrans, is an ecological engineer that can significantly modify the habitat of free-hanging aerial prop roots of Rhizophora mangle. The wood-boring isopod extensively burrows into red mangrove aerial prop roots for habitat and protection from desiccation and access to phytoplankton. However, the burrows created have major consequences on the mangrove habitat and aerial root inhabitants. It has been suggested that sessile species residing in aerial root communities can either encourage or discourage colonization by S. terebrans. Abiotic factors can affect the distribution and abundance of mangrove forest and are the same factors which determine the composition and abundance of organisms living on the roots. Surveys indicated that burrowing damage was found predominately in the first 20 cm of the root tip. Exploratory Structural Equation Modeling (SEM) was used to test multivariate hypothesized models looking at habitat relationships with S. terebrans in aerial root communities. Temperature and dissolved oxygen were shown to be important drivers in affecting submerged root length of aerial roots. Ultimately, the indirect effects between these parameters proved to be stronger in influencing the barnacle – isopod association, which causes direct negative effects on submerged root length. Colonial tunicates showed weak effects in masking aerial roots from the damaging barnacle – isopod association. Chlorophyll a was used as a proxy for phytoplankton biomass and proved to be less influential than habitat protection for S. terebrans. Results highlight the need for experimentation in addition to modeling in order to determine the mechanisms influencing aerial root community inhabitants and further effects on the habitat. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection

The main objective of this research was to analyze how well my proposed Foundation Species Interaction model explained the benthic communities found on red mangrove (Rhizophora mangle) prop roots. This research investigated the connections between the primary foundation species (mangroves), the dominant secondary foundations species (oysters, sponges, and barnacles), and the resulting biodiversity in order to understand the temporal and spatial variability of the ecosystems at different community levels. Chapter 1 was dedicated to explaining my change in ecological theory, the Foundation Species Interaction model. The interactions included in the model between the foundations species that were examined were the mutualistic (+, +), commensal (+, 0), and parasitic (+, -) interactions. Chapter 2 focused on exploration of the mangrove ecosystem in Southeast Florida and establishing where the secondary foundation species and prop root epibionts where found along the latitudinal gradient. The survey investigated the connections between mangroves, the dominant secondary foundations species (e.g. oysters, sponges, and barnacles), and the resulting biodiversity to understand the temporal and spatial variability of the ecosystems at different community levels. Chapter 3 was dedicated to testing the Foundation Species Interaction model’s ability to predict the biodiversity along the latitudinal gradient of the survey. The difference in mangrove prop root communities were largely explained by where the communities laid along the latitudinal gradient and by secondary foundation species presence. The shift from one foundation species to another had sizable effects on biodiversity. Chapter 4 combined the Foundation Species Interaction model with the established predation hypothesis and tested their abilities to explain biodiversity along the latitudinal gradient. This allowed for shifts in community structure to be examined for top-down and bottom-up influences. Predation effects changed along the latitudinal gradient, as the predation effects changed so did the effects of each of the individual foundation species. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection