The Comprehensive Everglades Restoration Plan (CERP), which is still in progress, aims to bring back the Florida Everglades’ historic flow in order to improve the ecosystem’s health, which has declined due to deteriorating water quality and habitat loss.
Along with a thriving tourism industry, the Southwest Florida coast, Florida Reef Tract, and Florida Bay together support an abundance of fish, coral, and underwater vegetation. The Florida Bay ecosystem, which is in the middle of this area, is directly affected by these watershed inputs, and it is important for ecosystems further downriver because it acts as a buffer.
Redirecting freshwater flow to Everglades is expected to make it less salty, but it could also increase the flow of nutrients that make phytoplankton blooms grow more quickly.
There is a lot of proof that these waters and the associated nutrients can move further downstream and affect the Florida Reef Tract and the National Marine Sanctuary. Before water reaches the Florida Keys, it undergoes changes in quality due to interactions between nutrient inputs, phytoplankton blooms, and sediment processes. The transport pathways and ensuing biogeochemical responses are complicated. Climate change, like sea level rise, is changing the conditions at the oceanic edges of the regions as well as the hydrological conditions and outputs of watersheds at the same time.
The ability of these watershed impacts to be predicted is currently limited. Numerous discrete, non-continuous water samples are used for the majority of biogeochemical observations. The area needs new ways to put all of the scattered observations and biogeochemical theories that are currently available into a system that makes sense right away.
Researchers at Florida Atlantic University‘s Harbor Branch Oceanographic Institute have been awarded a $350,000 grant from the US Environmental Protection Agency to study the connectivity between the Everglades and the Florida Keys via the Florida Bay. For the area, they are creating an ocean model, a novel tool to examine and diagnose key processes holistically through numerical simulations and experiments and to forecast changes in how the environment will react to factors such as water management, ecological restoration, and climate change.
Mingshun Jiang, Ph.D., principal investigator, physical oceanographer specializing in ocean coupled physical-biogeochemical-ecological modeling, and associate research professor at FAU Harbor Branch, said that when fully developed and validated, “our model is expected to be a powerful tool that is currently lacking for this region.” Its goal is to offer a variety of ecological and environmental details on the current condition of the larger Florida Bay ecosystem as well as any potential changes in the near future. Importantly, our model might be able to predict harmful algal blooms, fisheries resources, and the coverage of underwater aquatic vegetation under climate change and/or CERP management scenarios.
Jiang and co-PI Laurent Chérubin, Ph.D., a physical oceanographer with expertise in the study of ocean dynamics and a research professor at FAU Harbor Branch, will measure currents and water quality parameters at various significant locations in the Florida Bay throughout the dry and wet seasons to help with the model development. Estimates of the export of organic matter and nutrients from Florida Bay to the Florida Reef Tract and the Florida Keys National Marine Sanctuary will be measured.
Jiang and Chérubin will release neutrally buoyant (artificial) drifters at predetermined sites and track their trajectories to observe the movement of water and related pollutants. They will use these drifters to look into how freshwater moves through the Florida Bay, especially in the northeastern section. In shallow waters like Florida’s Indian River Lagoon, these drifters have been used to study the transport and dispersion of water.
Three small benthic landers will be moored as part of the fieldwork, and each one will be fitted with an acoustic Doppler current profiler (ADCP) and a water quality monitoring and sampling meter. The scientists will put their equipment in key spots to measure water exchanges between the northeastern basin, which gets a lot of freshwater nutrients, and the southeastern basin. They will also measure water exchanges between Florida Bay and the southwest Florida shelf, where fluxes are still very uncertain.
A new biogeochemical model will be created to simulate the cycles of nutrients (nitrogen, phosphorus), phytoplankton blooms, including the red tide-causing Karenia brevis and the blue-green algal blooms, zooplankton, and dissolved oxygen. To integrate the empirical theories and observations, this model will be coupled with an existing hydrodynamic model. Researchers will specifically quantify the export of nutrients and organic matter from Florida Bay and assess the effects of this export on nutrients, phytoplankton blooms, and water clarity. They will do this by combining the new model with both recent and historical measurements.
According to Chérubin, “New and historical data combined with our modeling will allow us to construct a full picture of the connectivity of waters and associated pollutants such as nutrients, organics, and other emerging pollutants like microplastics in this region under various conditions, including wet and dry seasons as well as storms.” The project’s authors write: “The findings from our project will assist water management agencies in creating better plans for reducing the negative effects of discharges from the Everglades on the environment, the ecosystem, and people, as well as possibly enhance efforts to restore habitat for seagrass and corals,” the project’s authors write.
Participants in the project include the University of South Florida; Florida International University; Fish and Wildlife Research Institute; and NOAA’s Atlantic Oceanographic and Meteorological Laboratory.
