Metadata

Description
<emphasis role="strong">1. Soil Sediment Cores</emphasis>
We used a comprehensive spatial sampling design (i.e., transect sites and discrete sites) to compare gradients in storm deposits and nutrient inputs associated with Hurricane Irma across mangrove sites in the FCE. We measured the thickness, distribution, and physico-chemical properties (bulk density, OM content, total C, N, P, TOC, TIC, and Ca-bound P) of storm sediments using duplicate cores collected at different distances along transect sites and discrete sites across the FCE. All soil-sediment cores were collected with a piston core (2.5 cm diameter x 15 cm length) and sectioned into two layers, storm sediments (variable depths) and surface (top 10 cm) mangrove soils, and the depth of each layer was registered. Each layer was stored separately in pre-labeled 50 mL centrifuge tubes, placed on ice, and transported to the laboratory for further analyses using standard protocols. For the transect data, we used a randomized block ANOVA design to test for differences in physico-chemical variables among sites, distance along transects, and layers (soil vs. sediment). Data collected within the discrete sites were analyzed separately with a two-way ANOVA, with sites and layers as main factors.
Duplicate soil-sediment cores were collected with a piston corer and sectioned into two layers, storm sediments (variable depths) and surface (top 10 cm) mangrove soils, and the depth of each layer was registered. Each layer was stored separately in pre-labeled 50 mL centrifuge tubes, placed on ice, and transported to the laboratory for further analyses.
<emphasis role="strong">2. Total P in mangrove leaf litter: </emphasis>
Mangrove litterfall dynamics have been monitored in all Shark River sites (SRS-4, SRS-5, SRS-6) since January 2001 using the same collection method stated in Castañeda-Moya et al. 2013 (metadata: LT_PP_Castaneda_001.v6_eml). Briefly, litterfall was collected monthly at all sites (10 baskets per site) using permanent 0.25 m2 wooden baskets supported approximately 1.3 m above the soil surface and lined with 1 mm mesh screening. Litterfall from each basket was sorted, dried, and weighed by leaf species, reproductive parts by species, and woody material. For this study, leaf litter data from three years (2008, 2014, 2018) were selected for each site to identify species-specific foliar P responses post-Wilma’s impact in 2005 and immediate post-Irma’s impact in 2017. Monthly leaf litter samples were analyzed separately by species for all years after grinding with a Wiley Mill to pass through a 40-µm mesh screen. Total leaf litter P was extracted with 1 N HCl after combustion in a furnace at 550 ºC (Aspila et al. 1976) and determined by colorimetric analysis using a segmented flow analysis Flow Solution IV autoanalyzer (OI Analytical). Relative (%) canopy P retranslocation was calculated using P concentrations of green and senescent (leaf litter) leaves for all mangrove species present at SRS-6. We used an unbalanced factorial ANOVA to evaluate differences in foliar P content of senescent leaves among mangrove species and sites. All pairwise comparisons were performed with Tukey’s honestly significant difference (HSD). Statistical analyses were performed with PROC MIXED (SAS Institute, Cary, NC, USA).
<emphasis role="strong">3. Porewater Soluble Reactive Phosphorus (SRP): </emphasis>
Porewater nutrients have been monitored in all Shark River mangrove sites since December 2000 using the same collection method stated in Castañeda-Moya et al. 2013. For this study, we used SRP concentrations for all sites from 2008 to 2018. Porewater samples were taken with a porewater sipper in the middle of each subplot at all sites. Concentrations of orthophosphate (i.e., SRP) were determined using either a spectrophotometer, a Lachat auto analyzer or an OI analytical autoanalyzer. Apha standard methods (1992) were used to derive the nutrient concentrations.
Two permanent plots (20x20 m) were established in each mangrove site, which where subdivided into four 10x10 m subplots. In the middle of each subplot porewater samples for nutrient and sulfide analyses have been collected repeatedly 2-3 times a year over 19 years next to physical data. The null hypothesis is that there is no significant difference between the mangrove sites that are monitored.
<emphasis role="strong">4. Quality Control on all Datasets:</emphasis>
Dataset is inspected by PI for QA/QC; descriptive statistics, normal distribution plots, standard validation checks for negative numbers, graphs to detect potential outliers Nutrient dataset QA/QC performed during analysis of samples; samples with 5% between lab replicates were redone; data was graphed to check for outliers
<emphasis role="strong">5. References cited:</emphasis>
<ulink url="http://dx.doi.org/10.1016/j.foreco.2013.07.011">Castañeda-Moya, E., R.R. Twilley and V.H. Rivera-Monroy. 2013. Allocation of biomass and net primary productivity of mangrove forests along environmental gradients in the Florida Coastal Everglades, USA. Forest Ecology and Management 307: 226-241</ulink>
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<ulink url="https://doi.org/10.1016/j.foreco.2013.07.011">https://doi.org/10.1016/j.foreco.2013.07.011</ulink>

Description
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