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Abstract Tropical forests are expected to experience unprecedented warming and increases in hurricane disturbances in the coming decades; yet, our understanding of how these productive systems, especially their belowground component, will respond to the combined effects of varied environmental changes remains empirically limited. Here we evaluated the responses of root dynamics (production, mortality, and biomass) to soil and understory warming (+4°C) and after two consecutive tropical hurricanes in our in situ warming experiment in a tropical forest of Puerto Rico: Tropical Responses to Altered Climate Experiment (TRACE). We collected minirhizotron images from three warmed plots and three control plots of 12 m2. Following Hurricanes Irma and María in September 2017, the infrared heater warming treatment was suspended for repairs, which allowed us to explore potential legacy effects of prior warming on forest recovery. We found that warming significantly reduced root production and root biomass over time. Following hurricane disturbance, both root biomass and production increased substantially across all plots; the root biomass increased 2.8‐fold in controls but only 1.6‐fold in previously warmed plots. This pattern held true for both herbaceous and woody roots, suggesting that the consistent antecedent warming conditions reduced root capacity to recover following hurricane disturbance. Root production and mortality were both related to soil ammonium nitrogen and microbial biomass nitrogen before and after the hurricanes. This experiment has provided an unprecedented look at the complex interactive effects of disturbance and climate change on the root component of a tropical forested ecosystem. A decrease in root production in a warmer world and slower root recovery after a major hurricane disturbance, as observed here, are likely to have longer‐term consequences for tropical forest responses to future global change.
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This content will become publicly available on November 1, 2026
Long‐term root dynamics of subtropical mangroves following Hurricanes Wilma and Irma in the Florida Everglades, USA
Abstract Hurricanes are among the most destructive natural disturbances in mangroves, altering community structure and ecological processes. Despite their impacts, few studies have assessed changes in belowground root processes (i.e., biomass, production, decomposition) following major hurricanes. Here, we quantified and compared changes in mangrove root processes in the Florida Coastal Everglades before (pre‐hurricane period: 2000–2004) and after post‐hurricane periods (post‐Wilma, May 2012; immediate‐post‐Irma, March 2018; post‐Irma, March 2023). We assessed spatiotemporal patterns in root dynamics across four mangrove sites (upstream, midstream, downstream, and estuary mouth) along a well‐defined soil phosphorus fertility gradient in the Shark River estuary. Root biomass carbon stocks were highest in the immediate‐post‐Irma and post‐Irma periods. The midstream site had the highest root C stocks, whereas the downstream site had the lowest across periods. Root size class distribution shifted considerably post‐hurricane, with fine roots accounting for 32% (post‐Wilma) to 66% (immediate‐post‐Irma and post‐Irma) of the total root C stocks across sites. However, root production did not vary among periods at any site, although estimates were higher midstream compared to upstream or downstream. Root total nitrogen and P were ~1.3 times higher in the post‐Irma period compared to other periods, with root P consistently increasing from upstream to the estuary mouth. Fine root turnover rates were lower post‐hurricane compared to pre‐hurricane across sites. Root decay rates declined post‐Irma at all sites, except at the midstream site. Our findings suggest that P‐rich sediments deposited by hurricanes can enhance belowground C allocation by increasing root biomass and nutrient uptake, while reducing root turnover to facilitate forest recovery. These responses underscore the strong phenotypic plasticity and resilience of mangrove roots in P‐limited carbonate settings, highlighting their critical role in C sequestration, resilience, and ecosystem stability as climate‐related disturbances and sea‐level rise intensify.
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- PAR ID:
- 10650783
- Publisher / Repository:
- Ecological Society of America
- Date Published:
- Journal Name:
- Ecosphere
- Volume:
- 16
- Issue:
- 11
- ISSN:
- 2150-8925
- Subject(s) / Keyword(s):
- Florida Coastal Everglades Hurricane Irma Hurricane Wilma mangroves P availability root biomass root decomposition root productivity
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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