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Monthly litterfall data is being collected in two mangrove-dominated regions (Shark River and Taylor Slough) in South Florida. Three sites (SRS4, SRS5, SRS6) in the Shark River region and one site (TS/Ph8) in the Joe Bay area region were used to characterize patterns of litterfall production. At each mangrove site 10 litter baskets (0.5 x 0.5 m) were placed in two 20 x 20 m plots (five baskets per plot). Data have been collected since January 2001. Statistical analysis is being performed. See also Shark River mangrove litterfall carbon and nutrients data package knb-lter-fce.1266 (https://portal.edirepository.org/nis/mapbrowse?scope=knb-lter-fce&identifier=1266).
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This content will become publicly available on June 27, 2026
Incorporating uncertainty in a wetland soil accretion model (NUMAN 2.0) to test generality across coastal environmental settings of south Florida
Understanding the relative contributions of aboveground and belowground processes to soil accretion and carbon density may explain carbon sequestration rates in mangroves across different coastal environmental settings. We reformulated the nutrient mangrove model (NUMAN) by improving algorithms and uncertainty analysis using literature values and site-specific observations to evaluate the relative contributions of organic and inorganic sedimentation for three mangrove sites with marked soil fertility gradients reflected by nitrogen-to-phosphorus (N:P) ratios including Shark River (N:P = 28), Rookery Bay (N:P = 54–78), and Taylor Slough (N:P = 102) in south Florida. NUMAN 2.0 considers cellulose as a refractory organic-matter sub-pool and simultaneously incorporates coarse-root inputs to soil formation. The model simulation also captures root necromass accumulation. Monte Carlo (MC) simulations (N = 1000 per site) were conducted to capture uncertainty by treating five key parameters as random variables: lignin content in fine, coarse, and large roots; inorganic sediment loading; and root biomass at the surface. With robust mass balancing of organic matter, NUMAN 2.0 generates precise predictions of surface accretion and carbon density. NUMAN 2.0 simulations estimated mean (standard deviation) soil carbon sequestration rates at 130.1 (55.4) for Shark River, 72.5 (3.7) for Rookery Bay, and 130.0 (83.9) g m-2 yr-1 for Taylor Slough, compared to field values of 123.0, 86.0, and 108.8 (8.7) g m-2 yr-1 , respectively. Simulation experiments with NUMAN 2.0 suggest that belowground organic matter dominates soil formation and carbon sequestration generally in coastal environmental settings with little allochthonous input such as carbonate settings, while wood litterfall should dominate soil organic matter in top 10 cm in estuaries, and bays.
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- PAR ID:
- 10643690
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Estuarine, Coastal and Shelf Science
- ISSN:
- 1096-0015
- Subject(s) / Keyword(s):
- NUMAN 2.0 Blue carbon Mangrove Soil properties Vertical accretion models Ecogeomorphology
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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