Root productivity of riverine and scrub mangroves from the Shark River Slough and Taylor Slough, Everglades National Park (FCE LTER), Florida, USA, March 2024 - April 2024

Root productivity of riverine and scrub mangroves in the Florida Everglades: Mangrove root productivity in the shallow root zone (0-45 cm depth) was estimated at all Shark River (SRS-4, SRS-5, SRS-6, SRS-7) and Taylor River (TS/Ph-6, TS/Ph-7) sites in March-April 2024. Root productivity was estimated with the ingrowth core technique using the same sampling protocol previously published for the study area (Castañeda-Moya et al. 2011). Ingrowth cores (10.2 cm diameter x 45 cm length) were made of synthetic material (3 mm mesh) and filled with root-free commercial sphagnum peat moss. This material has similar soil properties (i.e., bulk density, organic matter content, total C and N) as mangrove peat in our study sites as previously reported by Castañeda-Moya et al. (2011). Ingrowth cores were installed in holes made out with a PVC coring device (10.2 cm diameter x 45 cm length). At each site, 8 ingrowth cores were deployed vertically into the soil to a depth of 45 cm and retrieved one year later (March-April 2024). After collection, ingrowth cores were processed individually and initially rinsed with water through a 1-mm screen mesh to remove soil particles and peat moss material. Live roots were separated manually based on their buoyancy, turgor, and color (Castañeda-Moya et al. 2011; Cormier et al. 2015; Medina-Calderon et al. 2021). Live roots were further sorted into three size diameter classes including fine (<2 mm), small (2-5 mm), and coarse (5-20 mm). Roots greater than 20 mm in diameter were not included in this study due to sampling limitations (i.e., core area). All root samples were oven-dried at 60°C to a constant mass and weighed. Root growth within each ingrowth core following one year of incubation was used to estimate annual root productivity (g m⁻² yr⁻¹) in the shallow root zone across all mangrove sites. All data collection and processing were funded by FCE-LTER. Data collection is complete. References: Castañeda-Moya, E., R.R. Twilley, V.H. Rivera-Monroy, B.D. Marx, C. Coronado-Molina, and S.M.L. Ewe. 2011. Patterns of root dynamics in mangrove forests along environmental gradients in the Florida Coastal Everglades, USA. Ecosystems 14: 1178-1195. https://doi.org/10.1007/s10021-011-9473-3. Cormier, N., R.R. Twilley, C.K. Ewel, and K.W. Krauss. 2015. Fine root productivity varies along nitrogen and phosphorus gradients in high-rainfall mangrove forests of Micronesia. Hydrobiologia 750, 69-87. Medina-Calderon, J.H., J.E. Mancera-Pineda, E. Castañeda-Moya, and V.H. Rivera-Monroy. 2021. Hydroperiod and salinity interactions control mangrove root dynamics in a karstic oceanic island in the Caribbean Sea (San Andres, Colombia). Frontiers in Marine Science 7: 598132. https://doi.org/10.3389/fmars.2020.598132.