This dataset package encompasses measurements from field surveys of mangrove regeneration, porewater variables, and light conditions across six mangrove sites in the coastal Everglades. The goal of this project was to quantify mangrove regeneration of seedlings and saplings in mid- and downstream locations within three estuaries in Everglades National Park, Florida, USA. We assessed the effects of porewater variables and light conditions on the observed regeneration patterns. The package includes seven datasets: FCE1268_Porewater: Contains measurements of porewater salinity, sulfide, ammonia, nitrite, orthophosphate, and nitrate at a 30 cm depth. Porewater surveys were conducted biannually from 09-10-2020 to 05-17-2022. See also similar porewater data for Florida Coastal Everglades (FCE) long-term sites in data packages knb-lter-fce.1169 and knb-lter-fce.1171, which contain data for SRS-5 and SRS-6, available in the FCE LTER website's data catalog or the EDI repository. FCE1268_Foliar_Nutrient_Content dataset, collected in August 2022, includes measurements of foliar nutrient content (total carbon, total nitrogen, and total phosphorus) for three mangrove species (A. germinans, L. racemosa, R. mangle) of two life stages—seedlings (height < 1 m) and saplings (height ≥ 1 m and Diameter at Breast Height (DBH) < 2.5 cm). FCE1268_Light contains light intensity (foot-candle) measurements taken at 1-hour intervals from 09-18-2020 to 08-29-2022 at mangrove sites and converted photosynthetic active radiation values from an outdoor mesocosm experiment. FCE1268_Sapling_Density provides biannual count measurements of individuals at the sapling plot level (4 m^-2) within each site from 07-09-2020 to 08-29-2022. FCE1268_Seedling_Density contains biannual count measurements of individuals at the seedling plot level (m^-2) within each site from 07-07-2020 to 08-29-2022. FCE1268_Sapling_Regeneration contains height, crown area, and stem elongation measurements of tagged sapling individuals at the plot level (4 m^-2) from 07-09-2020 to 08-29-2022. FCE1268_Seedling_Regeneration contains height, crown area, and stem elongation measurements of tagged seedling individuals at the plot level (m^-2) from 07-07-2020 to 08-29-2022. Data collection for all datasets is complete.
more »
« less
Multiple factors explain species‐specific regeneration of mangrove seedlings and saplings after a major hurricane
Abstract Mangroves play a crucial role in mitigating hurricane impacts in coastal ecosystems, and their adaptive traits enable regeneration and forest recovery following these disturbances. Yet, how species‐specific regeneration varies across life stages and interacts with environmental conditions is poorly understood. We quantified regeneration rates of three dominant species of mangrove seedlings and saplings (Avicennia germinans,Laguncularia racemosa, andRhizophora mangle) recovering from a major hurricane. We selected forests with varying light availability and phosphorus (P) gradients in the Everglades (Florida, USA). From 2020 to 2022, we measured biannual stem elongation, height, and density of seedlings and saplings, and collected porewater variables (salinity, sulfide, and inorganic nutrients) and continuous light intensity to assess species‐specific drivers of regeneration. Species‐specific growth rates, total height, and density varied across sites, driven by differences in porewater P and light. Growth rates ofR. mangleseedlings and bothR. mangleandL. racemosasaplings were influenced by light, whileA. germinansgrowth rates were unaffected. OnlyR. mangleandL. racemosasaplings were influenced by porewater P, while growth of both seedlings and saplings was unaffected by porewater salinity and sulfide. Mangrove regeneration post‐disturbance is explained by spatial differences in subsidies and stressors and the composition of species and life stages, underscoring complex regeneration strategies in mixed‐species forests.
more »
« less
- PAR ID:
- 10610388
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecosphere
- Volume:
- 16
- Issue:
- 6
- ISSN:
- 2150-8925
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Mangrove-forest sustainability hinges upon propagule recruitment and seedling retention. This study evaluates biophysical limitations to mangrove-seedling persistence by measuring anchoring force of two mangrove species (Rhizophora mangle L. and Avicennia germinans (L.) L.). Anchoring force was measured in 362 seedlings via lateral pull tests administered in mangrove forests of two subtropical estuaries and in laboratory-based experiments. Removal mechanism varied with seedling age: newly established seedlings failed due to root pull-out while seedlings older than 3 months failed by root breakage. The anchoring force of R. mangle seedlings was consistently and significantly greater than A. germinans (p = 0.002); however, force to remove A. germinans seedlings increased with growth at a faster rate (p < 0.001; A. germinans: 0.20–0.23 N/g biomass; R. mangle: 0.04–0.07 N/g biomass). Increasing density of surrounding vegetation had a positive effect (p = 0.04) on anchoring force of both species. Critical velocities at which seedlings become susceptible to instantaneous uprooting estimated from anchoring forces measured in the field were 1.20 m/s and 1.50 m/s, respectively, for R. mangle and A. germinans. As estimated critical velocities exceed typical flow magnitudes observed in field sites, removal of established seedlings likely occurs following erosion of sediments from the seedling base.more » « less
-
Ball, Marilyn (Ed.)Abstract Temperature and salinity are important regulators of mangrove range limits and productivity, but the physiological responses of mangroves to the interactive effects of temperature and salinity remain uncertain. We tested the hypothesis that salinity alters photosynthetic responses to seasonal changes in temperature and vapor pressure deficit (D), as well as thermal acclimation _of leaf respiration in black mangrove (Avicennia germinans). To test this hypothesis, we grew seedlings of A. germinans in an outdoor experiment for ~ 12 months under four treatments spanning 0 to 55 ppt porewater salinity. We repeatedly measured seedling growth and in situ rates of leaf net photosynthesis (Asat) and stomatal conductance to water vapor (gs) at prevailing leaf temperatures, along with estimated rates of Rubisco carboxylation (Vcmax) and electron transport for RuBP regeneration (Jmax), and measured rates of leaf respiration at 25 °C (Rarea25). We developed empirical models describing the seasonal response of leaf gas exchange and photosynthetic capacity to leaf temperature and D, and the response of Rarea25 to changes in mean daily air temperature. We tested the effect of salinity on model parameters. Over time, salinity had weak or inconsistent effects on Asat, gs and Rarea25. Salinity also had little effect on the biochemical parameters of photosynthesis (Vcmax, Jmax) and individual measurements of Asat, gs, Vcmax and Jmax showed a similar response to seasonal changes in temperature and D across all salinity treatments. Individual measurements of Rarea25 showed a similar inverse relationship with mean daily air temperature across all salinity treatments. We conclude that photosynthetic responses to seasonal changes in temperature and D, as well as seasonal temperature acclimation of leaf R, are largely consistent across a range of salinities in A. germinans. These results might simplify predictions of photosynthetic and respiratory responses to temperature in young mangroves.more » « less
-
This project examines mangrove forests as resilient, sustainable, and non-invasive shoreline protection in subtropical and tropical areas. Hydrodynamic data were collected from idealized Rhizophora mangle and Avicennia germinans forest models. The data were analyzed to identify trends between the heterogeneity of a mangrove forest and wave runup extents. Different species of mangroves have a distinctive root system which attributes to different coastal protection abilities. Shorter wave periods were most affected by mangrove configurations tested. Configurations dominated by R. mangle models resulted in overall smaller runup extents compared to configurations dominated by A. germinans models for the same wave conditions.more » « less
-
Mangrove forests along the coastlines of the tropical and sub-tropical western Atlantic are intermittently impacted by hurricanes and can be damaged by high-speed winds, high-energy storm surges, and storm surge sediment deposits that suffocate tree roots. This study quantified trends in damage, delayed mortality, and early signs of below- and aboveground recovery in mangrove forests in the Lower Florida Keys and Ten Thousand Islands following direct hits by Hurricane Irma in September 2017. Mangrove trees suffered 19% mortality at sites in the Lower Florida Keys and 11% in the Ten Thousand Islands 2–3 months post-storm; 9 months post-storm, mortality in these locations increased to 36% and 20%, respectively. Delayed mortality of mangrove trees was associated with the presence of a carbonate mud storm surge deposit on the forest floor. Mortality and severe branch damage were more common for mangrove trees than for mangrove saplings. Canopy coverage increased from 40% cover 1–2 months post-storm to 60% cover 3–6 months post-storm. Canopy coverage remained the same 9 months post-storm, providing light to an understory of predominantly Rhizophora mangle (red mangrove) seedlings. Soil shear strength was higher in the Lower Florida Keys and varied with depth; no significant trends were found in shear strength between fringe or basin plots. Rates of root growth, as assessed using root in-growth bags, were relatively low at 0.01–11.0 g m−2 month−1 and were higher in the Ten Thousand Islands. This study demonstrated that significant delayed mangrove mortality can occur 3–9 months after a hurricane has passed, with some mortality attributable to smothering by storm surge deposits.more » « less
An official website of the United States government
