Research History

FCE LTER Phases

• Phase I (2000-2006)

  FCE research began in 2000 with a focus on providing an understanding of key coastal ecosystem processes while also developing a platform for and linkages to related work in the wider Everglades research community. The primary research objective was to determine how freshwater from oligotrophic (nutrient-poor) marshes interacts with a marine source of the limiting nutrient, phosphorus (P), to control productivity in the estuarine ecotone — the zone where freshwater and marine supplies meet in the coastal Everglades. Researchers expected that primary productivity (the amount of living material produced by plants) would be greatest where freshwater supplies meet marine waters where P is more available. Permanent sites for regular sampling of water, soils, plants and animals were established along the main Everglades drainages, Taylor Slough-Panhandle (TS/Ph) and Shark River Slough (SRS), from freshwater canal inputs to the Gulf of Mexico.

  Research showed a wedge of increasing productivity toward the coast along the SRS transect where tides and storms delivery P-rich water to the mangrove forest. However, scientists also found an unexpected productivity peak in the estuarine ecotone of the TS/Ph transect, due to brackish groundwater delivery of P to ecotone plant communities. This work demonstrated how the Everglades are functionally "upside-down" relative to the classic estuary model, with seawater supplying limiting nutrients landward, rather than the other way around. These findings led us to further expand our trans-disciplinary research examining how freshwater flow restoration interacts with climate variability to influence the shape of this productivity gradient.

• Phase II (2007-2012)

  Phase II research focused further on the estuarine ecotones, particularly investigating how changes in freshwater flow brought about by restoration activities would impact ecosystem processes in these unique areas.

  Everglades Restoration was geared toward enhancing freshwater inflow to SRS but not to TS/Ph during this period, providing a landscape-scale "Grand Experiment" to test ideas about the function of this critical zone. However, delays in restoration projects caused scientists to postpone these plans, but in a way that would prove to be beneficial to restoration guidance. While restoration projects were stalled, researchers were able to characterize a high degree of variability from year to year in the ecosystem, driven by climate cycles and storm activities. For example, hydrologists were able to measure the rate that brackish groundwater moves into the estuarine ecotone during wet and dry years, resulting in improved targets for freshwater flow restoration that cover the range of natural climate variability experienced in the ecosystem.

  Researchers also showed how periodic storms can deliver coastal sediments and nutrients to the ecotone, further stimulating mangrove and seagrass production — in fact, making them among the most productive ecosystems on the planet. The carbon thereby generated can be stored in place or move about the ecosystem — FCE researchers have shown how carbon moves both in the water but also in the bodies of animals, including big sharks and alligators.

• Phase III (2013-2018)

  In FCE III, the FCE program has expanded its capacity in human dimensions research to explore how legacies of resource use decisions shape both the existing environment as well as future socio-ecological response to rapid climate and land-use change in this highly vulnerable landscape. Delays in freshwater restoration are increasing the rates and distance of intrusion of saltwater and nutrients into the interior of the Everglades, promoting continued landward movement of mangroves while reducing the areal extent of freshwater marsh. FCE III research is: 1) evaluating the source of socio-political conflicts over water distribution, and how solutions that improve inflows to the Everglades reduce or delay the effects of SLR on estuarine conditions in the coastal zone; 2) determining how the balance of fresh and marine water supplies to the oligohaline ecotone will control the rates and pathways of carbon (C) sequestration, storage, and export by influencing P availability, water residence time, and salinity; 3) characterizing spatial-temporal patterns in ecosystem sensitivity to, and legacies of, modifications of freshwater delivery to the Everglades that are driven by climate variability and land-use change, and; 4) developing future scenarios of freshwater distribution and use that maximize the human-environmental sustainability in regions like south Florida that face SLR.

  FCE scientists have discovered that sea level continues to rise in ways that impact coastal areas of the Everglades and urban Miami. We will know which of the sea level rise projections used by modelers are correct for our region in another 15-20 years. We have found that increasing exposure to marine water supplies is leading to the collapse of organic soils throughout the coastal zone, so we are conducting experiments to identify the causes. We are using our long-term datasets and experiments to improve our estimates of how freshwater restoration will prolong these effects of sea level rise, providing time for adaptation and mitigation of climate change impacts on coastal Florida. Through comparative research in other coastal areas, we are determining whether changes observed in the Everglades can be used to forecast changes in other coastal regions worldwide.

• Phase IV (2019 - 2025)

  Everglades restoration is increasing seasonal freshwater pulses while a 2017 hurricane delivered a storm surge pulse to the FCE, offering an unprecedented landscape-scale test of the overarching question: Will increased pulses of fresh and marine water and their associated resources maintain vegetated coastal ecosystems supporting highly connected food webs and valued ecosystem services while sea-level continues to rise?

  The FCE IV conceptual framework integrates theoretical concepts of ‘ecosystem development’ and ‘pulse dynamics’ to understand how social-ecological responses to increasing climate variability and extremes depend on the magnitude, timing, and duration of these ‘pulses’ and their interaction with other persistent changes (‘presses’). Four hierarchical research questions ask: (1) how the climate drivers of hydrologic presses and pulses are changing, (2) how governance of freshwater restoration reflects changing values of ecosystem services, (3) how ecological landscapes serve as endogenous filters that feed back to the climate system, and (4) how ecosystem structural and functional responses influence long-term ecosystem trajectories. These questions are addressed through continued long-term and new data collection along two transects with contrasting hydrologic presses and pulses, human dimensions research, a new ecosystem vulnerability experiment, process and landscape-scale modeling and scenarios approaches, and a large suite of collaborative projects sponsored by leveraged funding.