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Hurricanes can introduce metals into coastal systems. Unfortunately, metal concentrations are unknown in many hurricane prone locations. Here we measured vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, molybdenum, cadmium, antimony, barium, lead, and uranium in surface water, sediments, and seagrass (Thalassia testudinum) collected in seagrass beds and marinas around The Abacos, The Bahamas in November 2019, May 2020, and June and December 2021 to establish a post-Hurricane Dorian baseline, assess changes post-storm, and understand bioconcentration in seagrass. Metal concentrations were higher in marinas and several increased over time. Also, metal profiles in sediments became more similar over time. Together, these suggest that metals were impacted by Hurricane Dorian and are either returning to pre-storm conditions or increasing due to recovery-related activities. Thalassia testudinum uptakes most metals more readily from surface water than sediments. Therefore, seagrasses may phytoremediate metals, but also transfer metals to higher trophic levels.
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In the wake of a major hurricane: Differential effects on early vs. late successional seagrass species
Abstract At least 18 major storms have struck the Gulf of Mexico and Caribbean in the past 50 yr including Hurricane Harvey, a Category 4 storm that passed over extensive seagrass beds in the western Gulf of Mexico and became the second‐most expensive U.S. hurricane. We sought to identify the effects of an extreme hurricane on sediment physicochemical characteristics and seagrass species with contrasting life histories and morphologies. Surprisingly, Harvey's intense wind speeds resulted in decreases in blade length, vegetative cover, and greater overall loss ofThalassia, a persistent climax species relative toHalodule, a prolific pioneer species. Sediment ammonium and grain size changed, but not organic carbon. Our results indicate that effects of wind intensity are not only restricted to the differential impacts on seagrasses, but on the physicochemical characteristics of the sediments. These changes, coupled with the slow colonization abilities ofThalassia, may prolong recovery of disturbed seagrass meadows.
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- Award ID(s):
- 1807143
- PAR ID:
- 10448060
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Limnology and Oceanography Letters
- Volume:
- 4
- Issue:
- 5
- ISSN:
- 2378-2242
- Page Range / eLocation ID:
- p. 155-163
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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