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Wang, P.; Royer, E.L.; Jackson, K., and Gutierrez, S., 2024. Impacts of Hurricane Ian along the low-lying southwest Florida coast (USA) in 2022: Lessons learned. Journal of Coastal Research, 40(5), 827–851. Charlotte (North Carolina), ISSN 0749-0208. Hurricane Ian made landfall in the low-lying, densely populated, and developed southwestern Florida coast on 28 September 2022 as a large and slow-moving category 4 hurricane. Various U.S. federal and state agencies collected a large and comprehensive data set, including pre- and poststorm airborne LIDAR topography, in situ water level and wave measurements at numerous locations before, during, and after the storm, and poststorm high-water marks over a large area. This study reports results from a series of poststorm field investigations including ground observations of beach-dune erosion and deposition, catastrophic damage to various infrastructure, and widespread distribution of non-biodegradable materials washed into the estuary and numerous mangrove islands. Hurricane Ian induced large-scale inundation in low-lying southwest Florida, submerging all the barrier islands bordering Charlotte Harbor estuary, all the islands within the estuary, and up to 5 km into the mainland. Dense tree-type vegetation limited the landward penetration of beach-dune erosion and overwash deposition along the barrier islands. Net sand-volume loss from the beach-dune system ranged 10–25 m3/m and was controlled by the deep submergence of the system during the peak of the storm. The extremely high storm surge of up to 5.2 m above mean sea level generated by Hurricane Ian caused severe damage to the built environments over a large area. High storm waves superimposed on the elevated water level, reaching 1.2 m at the seaward edge of vegetated dunes, contributed to the destruction along the barrier islands. Hurricane Ian distributed a tremendous amount of non-biodegradable artificial debris over a large area and into sensitive natural environments, including numerous mangrove islands, barrier-island interior wetlands, and the estuary waterbody. Measures to prevent materials such as single-use plastics, insulation fibers, and household appliances from being washed into sensitive environments should be a significant part of prestorm preparation. [ABSTRACT FROM AUTHOR]

Although shell middens and mounds often occupy the same intertidal spaces as coastal wetlands, biophysical interactions between these cultural features and wetlands are under-investigated. To this end, our geoarchaeological and zooarchaeological research at three coastal archaeological sites within the Tampa Bay Estuary, USA, sought to understand the interactions between shell-bearing sites, sea-level rise, storms, and migrating wetland habitats. Percussion core transects document the accretion of mangrove peat atop intact shell midden, illustrating the ability of mangrove forests to encroach shell midden and preserve cultural material below. Landward wetland deposits are thicker and muddier than those along the seaward margin of the sites, suggesting that shell-bearing sites attenuate wave energy much like other shoreline stabilization structures. Differences in sedimentology, stratigraphy, and invertebrate species compositions highlight the variability in storm impacts between sites. Storm-driven depositional events are identified by medium-to-fine sand beds with high densities of fragmented shell and small intertidal zone snails. Geospatial analyses indicate that wetland encroachment is already occurring at 247 archaeological sites within the Tampa Bay Estuary. Approximately 100 additional archaeological sites currently located in upland habitats may provide topographic relief for migrating coastal wetlands in the future. We contend that shell middens and mounds constructed by Indigenous peoples are important components within estuarine mosaics, as they have been for millennia. We advocate for further collaboration between archaeologists and estuary managers and the inclusion of descendant communities to co-manage the future of their past. [ABSTRACT FROM AUTHOR]

Historical descriptions and archaeological research provide a compelling association of the Native town of Tocobaga with the Safety Harbor site (8PI2), in Tampa Bay, Florida. The Spanish established a mission-fort at Tocobaga in 1567, but it was short-lived: responding to abuse by the colonizers, the Tocobagans killed the soldiers who had been left at the town and the Spanish burned the town in retaliation. We employ the metaphor of effacement, in its original referent to the wearing away of the surface of a coin, to describe the manner in which the colonial destruction of the town provided an opportunity for imposition of new meanings on the landscape of Tocobaga in the modern era: first as a plantation and "pleasure garden," next as an ancient ruin and archaeological site, and later as a reform park. Archaeology is part of the effacement of the Native town—the remnants of Tocobaga were reinscribed as the type site for the Safety Harbor–period and the eponymous Mississippian-period (1010–1550) material culture complex. However, archaeology—including our recent testing—also provides a means for understanding such concepts as effacements, as well as the persistence of materiality. [ABSTRACT FROM AUTHOR]

Jackson, K.; Wang, P.; Pluckhahn, T.J.; Rogers, J.A., and Thompson, V.D., 2023. Stratigraphic framework, paleoenvironments, and Indigenous terraforming of inshore estuarine subbasins in Tampa Bay, Florida, U.S.A. Journal of Coastal Research, 39(5), 779–815. Charlotte (North Carolina), ISSN 0749-0208. Tampa Bay is a karst-controlled estuary system on Florida's central peninsular Gulf of Mexico coast. Although previous work has reconstructed late-Pleistocene environments (ca. 20–11.5 kya) and early marine influence (ca. 8–5.5 kya) in deeper central portions of the bay, the estuarine development of the shallow inshore subbasins remains poorly understood. Across the late Holocene, Indigenous societies terraformed the coastal strand with large volumes of estuarine mollusk shell, and these anthropogenic landforms constitute coastal barriers that partially enclose marginal tidal bayous. This study integrates sediment coring and archaeological excavations to reconstruct the Holocene estuarine evolution of four inshore subbasins within Tampa Bay. This study synthesizes sedimentological, macrofossil, and archaeological data to describe and differentiate seven sedimentary facies and 18 subfacies representing weathered Miocene limestone at the base, overlain by late-Pleistocene freshwater wetland deposits, followed by Holocene estuarine sediments and late-Holocene shell-terraformed settlements. Four stratigraphic cross-sections and >100 radiocarbon assays are utilized to interpret the sequences of inshore estuary development, situate ancient shell-bearing Native settlements within a geologic and paleoenvironmental framework, and resolve elements of mid- and late-Holocene sea-level history. [ABSTRACT FROM AUTHOR]

Ecological regime shifts are expected to increase this century as climate change propagates cascading effects across ecosystems with coupled elements. Here, we demonstrate that the climate-driven salt marsh-to-mangrove transition does not occur in isolation but is linked to lesser-known oyster reef-to-mangrove regime shifts through the provision of mangrove propagules. Using aerial imagery spanning 82 y, we found that 83% of oyster reefs without any initial mangrove cover fully converted to mangrove islands and that mean (± SD) time to conversion was 29.1 ± 9.6 y. In situ assessments of mangrove islands suggest substantial changes in ecosystem structure during conversion, while radiocarbon dates of underlying reef formation indicate that such transitions are abrupt relative to centuries-old reefs. Rapid transition occurred following release from freezes below the red mangrove (Rhizophora mangle) physiological tolerance limit (27.3 °C) and after adjacent marsh-to-mangrove conversion. Additional nonclimatemediated drivers of ecosystem change were also identified, including oyster reef exposure to wind-driven waves. Coupling of regime shifts arises from the growing supply of mangrove propagules from preceding and adjacent marsh-to-mangrove conversion. Climate projections near the mangrove range limit on the Gulf coast of Florida suggest that regime shifts will begin to transform subtropical estuaries by 2070 if propagule supply keeps pace with predicted warming. Although it will become increasingly difficult to maintain extant oyster habitat with tropicalization, restoring oyster reefs in high-exposure settings or active removal of mangrove seedlings could slow the coupled impacts of climate change shown here. [ABSTRACT FROM AUTHOR]

While seldom integrated within coastal archaeological research in Southeastern North America, vegetation histories derived from palynological data offer valuable records of ancient landscape transformations driven by climatic flux, sea-level oscillations, and anthropogenic modifications. In this paper, we develop a paleo-historical-ecological reconstruction from preliminary analyses on fossil pollen assemblages preserved within marsh, hammock, and shell-midden soils at the Crystal River site (8CI1), a mound center on Florida's west-central coast occupied throughout the first millennium AD. When contextualized alongside paleoenvironmental records from western Florida and farther afield, our analysis suggests that the nature and timing of late-Holocene climatic changes varied little between different sub-regions of Florida's Gulf Coast, but also that manifestations of eustatic sea-level flux may have been highly localized. [ABSTRACT FROM AUTHOR]