The Effect of Water Level and Salinity on Carbon Dynamics in an Everglades Subtropical Brackish Ecotone Wetland

Authors

Amanda Richey, Florida International UniversityFollow

Document Type

Thesis

Degree

Master of Science (MS)

Major/Program

Biology

First Advisor's Name

Adam Roddy

First Advisor's Committee Title

Committee Chair

Second Advisor's Name

John Kominoski

Second Advisor's Committee Title

Committee Member

Third Advisor's Name

Paulo Olivas

Third Advisor's Committee Title

Committee Member

Keywords

coastal ecotones, hydrology, mangrove, sawgrass, eddy covariance

Date of Defense

7-2023

Abstract

Changes in water level and salinity cause dynamic shifts in plant community composition and ecotone development in coastal ecosystems. Given varying carbon (C) sequestration capacities of coastal wetlands, it is important to understand how hydrology and saltwater intrusion affect CO₂ fluxes. This study’s objective was to understand the impact of hydrology in an ecotone transitioning from a freshwater marl prairie to a mangrove scrub in the Everglades. I explored long-term trends in water level and salinity and identified the relationship between these two variables. Next, I compared rates of net ecosystem exchange of CO₂ (NEE) under different hydrologic conditions by fitting light and temperature response curves. Ecosystem CO₂ uptake rates were less sensitive to changes in water level than respiration rates. Although sawgrass (Cladium jamaicense) declined over the study period, the proliferation of mangroves (Rhizophora mangle) maintained CO₂ uptake, making the ecotone’s C sequestration capacity resilient to variable hydrology.

Identifier

FIDC011147

ORCID

0000-0002-4251-07150

Recommended Citation

Richey, Amanda, "The Effect of Water Level and Salinity on Carbon Dynamics in an Everglades Subtropical Brackish Ecotone Wetland" (2023). FIU Electronic Theses and Dissertations. 5428.
https://digitalcommons.fiu.edu/etd/5428