Histosols (~1.3% of Earth’s land surface), store approximately one-quarter of the soil organic carbon (SOC). Due to agricultural drainage, these organic-rich soils are highly vulnerable to microbial oxidation and soil mineralization, leading to subsidence and emission of carbon (C) flux (CO₂ and CH₄). In Everglades Agricultural Area (EAA), FL, prolonged cultivation has resulted in significant subsidence, posing challenges to the long-term sustainability of agriculture. This study aims to enhance the formation of mineral-associated organic matter (MAOM), the most stable C pool, through the targeted soil amendments (organic/inorganic) in managed histosols. I hypothesize that soil amendments in such degraded soils will enhance MAOM formation, mitigating C emissions and subsidence. A multi-scale approach will be applied through investigation of MAOM pool, laboratory incubations, and open-air mesocosm across seasonal and hydrologic conditions. Preliminary results showed that unassociated SOC predominated over physicochemically-stabilized C in EAA soils. Ongoing lab results show that lime reduces CO₂ release, indicating potential for greater C stabilization. The findings will help guide amendment–driven strategies to enhance MAOM formation as well as improve sustainable land management practices and mitigating climate influencing C flux.
Mumtahina Riza
Dr. Lisa Chambers, Advisor
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