106-57 Elucidating Carbon Burial Natural Mangrove Soils on Florida’s Gulf Coast Using the Radiocarbon Bomb Curve

Session: 37th Annual Undergraduate Research Exhibition Sponsored by Sigma Gamma Epsilon (Posters)

Poster Booth No.: 143

Presenting Author:

Junnieska Gutierrez-Paiz

Authors:

Gutierrez-Paiz, Junnieska¹, Aguilar, Beatriz Alejandra², Smoak, Joseph³, Rodriguez, Estafania⁴, Rosenheim, Brad⁵

(1) University of Florid, Gainesville, FL, USA, (2) College of Marine Science, University of South Florida, Saint Petersburg, FL, USA, (3) School of Geosciences, University of South Florida, Saint Petersburg, FL, USA, (4) University of South Florida, Saint Petersburg, FL, USA, (5) College of Marine Science, University of South Florida, Saint Petersburg, FL, USA,

Abstract:

Mangrove habitats are coastal wetlands that trap and store carbon in their soils, making them important carbon sinks and natural buffers against anthropogenic climate change . Mangrove soils, rich in organic matter, accumulate rapidly enough to record the elevated ¹⁴C signatures from mid-20^th century thermonuclear bomb testing. We applied an independent chronometer ( ²¹⁰Pb) to employ the radiocarbon bomb curve as a tracer of downward movement of atmospheric carbon in mangrove soils. A simple advection model was applied to determine the rate of downward transport of organic carbon at several sites. We compared radiocarbon bomb curves from two sites in Florida at different latitudes: Tampa Bay in the north, Naples further south, and the Ten Thousand Islands region furthest south. We used ²¹⁰Pb dates to constrain the rise, peak, and fall of the bomb curve at each location. Each sample was sieved to <63 micrometers and then acid-treated to remove inorganic carbon. By analyzing radiocarbon signals in soil cores, this study evaluated ¹⁴C signatures in relation to site elevation and location (regional). Advective modeling can relate the difference in ¹⁴C bomb curves between and within sites to processes such was water inundation, efflux of carbon, and simply by latitude. Our approach elucidates mangrove soil dynamics that are responsible for downward pumping of organic carbon, allowing us to gain insight into how blue carbon ecosystems contribute to carbon sequestration.

 

 

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-10632

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