Undergoing Research Activities

Investigating the extent of seawater intrusion into the coastal aquifer along the southern coastline of the Everglades and Miami-Dade County from 2003 until present. Salinity data obtained from shallow (<4 m) groundwater wells located near the coastline was obtained from the USGS and ENP databases. This data was used to investigate temporal trends in saltwater intrusion as well as to contour the spatial extent of saltwater intrusion. Furthermore, the relationships between groundwater and surface water levels, as well as groundwater and surface water salinity were investigated along the border of the mangrove and sawgrass ecotones of Everglades National Park. Coastal ecosystems are most susceptible to the predicted SLR of 50 to 100 cm in the next 100 years, as they will be at the forefront of increases in salinity and flooding frequency. Using data on species composition of upland forests Rene Price (link to her profile) headed investigations of changes in species composition relative to the freshwater saltwater interface (FWSWI) along the southern coastal Everglades.

We posit that the tolerance to drought resulting from freshwater limitation and or salinity maintains the disparity among upland species composition in relation to the FWSWI and determines organization of coastal plant communities along a mild gradient in elevation. Sternberg et al (2007) and Teh et al. (2008) (Sternberg, L., Teh, S.Y., Ewe, S., Miralles-Wilhelm, F.,and DeAngelis, D.L. 2007. Competition between hardwood hammocks and mangroves. Ecosystems 10: 648-660. ) & (Teh, S.Y., DeAngelis, D.L., Sternberg, L., Miralles-Wilhelm, F., Smith, T., and Koh, H. 2008. A simulation model for projecting changes in salinity concentrations and species dominance in the coastal margin habitats of the Everglades.

Ecological Modeling 213: 245-256. ) used a model of competition between hardwood hammocks and mangroves to show that ability to regulate stomatal conductance in the event of drought (shortage of freshwater or physiological drought caused by saline water) governs distribution of hardwood hammocks and mangroves. We applied the same model species composition of coastal upland forests in relation to the FSWSI, to investigate the effects of sea-level rise on the availability for freshwater recharge in the vadose zone. We then compared species composition of upland communities along an elevation gradient between 1998 and 2009 to examine if changes in species abundances reflect changes in salinity regimes of the watershed that influences the coastal plant community complex.