Floridians are no strangers to disturbances like hurricanes and heavy rainfall— in fact, we consider ourselves seasoned professionals in the matter. What we lack, however, is an understanding of how these episodic disturbances, and others like them, affect our invaluable Everglades ecosystem. Fortunately, FIU’s Florida Coastal Everglades LTER (FCE LTER) scientists are on it.
A recent synthesis paper written as a collaboration including several FCE LTER scientists and led by FCE Project Collaborator Dr. Stephen Davis, offers a deeper understanding of how episodic disturbances such as hurricanes, fire, and marsh dry-down affect the water quality of Everglades National Park (ENP).
Submitted as part of a special issue in the journal Ecosphere that stemmed from LTER workshops on the importance of high-energy storms in shaping LTER sites, the study revealed that these disturbances do in fact impact the water quality of ENP from days to years, depending on the type of disturbance and its intensity. The study also found that even in the highly managed Florida Everglades, the capacity for resilience is high in coastal wetland ecosystems that are exposed to high-energy tropical storms and other episodic events.
Using valuable long-term FCE data sets, the team was able to describe the impacts of these disturbances on surface water total Nitrogen (TN) and total Phosphorus (TP) concentrations— two nutrients that, in excess amounts, are detrimental to the Everglades ecosystem.
One such instance detailed in the paper is the deposition of marine-derived sediment from Hurricane Wilma which led to a doubling of TP in ENP’s Shark River Slough mangrove sites, only recovering to pre-disturbance levels after 5-6 years.
“Typically, we think of canals and agricultural inputs as sources of nutrients like Nitrogen and Phosphorus to the Everglades,” Davis said. “However, this work showed that these natural disturbances can mobilize measurable amounts of Nitrogen and Phosphorus from within the marsh or can deliver Phosphorus in the form of marine sediments that have a sustained impact on water quality in mangrove sites.”
Given the prevalence of large-scale disturbances in the Everglades, the limited knowledge of the effects of these disturbances on water quality dynamics, and the legal framework necessary to protect Everglades resources, this study highlights the need to develop tools that will help further investigate these issues and their consequences.