Sargassum Accumulation at Von D. Mizell-Eula Johnson State Park
Abstract
Sargassum is a typically floating phaeophyte (brown alga) with important ecosystem functions. It is a producer, generating biomass via photosynthesis, and providing habitat for small epipelagic organisms in the open ocean. In August 2022, large amounts of Sargassum were seen on the beach at the northern end of Von D. Mizell-Eula Johnson State Park (VDMEJSP), Dania Beach, Florida, up to 152cm thick. This disturbs the intertidal environment, which is typically composed of carbonate sands, and smothers infauna. Furthermore, this creates ephemeral habitats for species not typically associated here. The extent of Sargassum deposits was measured from 7 September through 25 October 2022. We measured thickness and extent of deposits using probes for Sargassum depth and GPS coordinates combined with GIS tools. In September, the deposit extended over 7,475m2 and by October 6th was reduced to 307.23m2 and on 25 October none was observed. Outer wind bands (40-53kph) of Hurricane Ian were primarily directed offshore on 28 September 2022, removing most Sargassum deposits. In the future, there will be increasing concern of beach smothering by Sargassum since productivity is enhanced by warming and nutrification from the Sahara dust associated with global climate change. In 2022 unprecedented beach accumulations were reported from many Caribbean Islands and Florida. The shoreline topography at the northern end of VDMEJSP increases Sargassum deposition due to the presence of artificial jetties that trap eastward transported algae. This study documents extensive accumulations of Sargassum at this location and discusses impacts on local environments and associated organisms.
Faculty Sponsors
Dr. Joshua Feingold
Project Type
Event
Location
Alvin Sherman Library
Start Date
4-5-2023 12:00 PM
End Date
4-6-2023 4:00 PM
Sargassum Accumulation at Von D. Mizell-Eula Johnson State Park
Alvin Sherman Library
Sargassum is a typically floating phaeophyte (brown alga) with important ecosystem functions. It is a producer, generating biomass via photosynthesis, and providing habitat for small epipelagic organisms in the open ocean. In August 2022, large amounts of Sargassum were seen on the beach at the northern end of Von D. Mizell-Eula Johnson State Park (VDMEJSP), Dania Beach, Florida, up to 152cm thick. This disturbs the intertidal environment, which is typically composed of carbonate sands, and smothers infauna. Furthermore, this creates ephemeral habitats for species not typically associated here. The extent of Sargassum deposits was measured from 7 September through 25 October 2022. We measured thickness and extent of deposits using probes for Sargassum depth and GPS coordinates combined with GIS tools. In September, the deposit extended over 7,475m2 and by October 6th was reduced to 307.23m2 and on 25 October none was observed. Outer wind bands (40-53kph) of Hurricane Ian were primarily directed offshore on 28 September 2022, removing most Sargassum deposits. In the future, there will be increasing concern of beach smothering by Sargassum since productivity is enhanced by warming and nutrification from the Sahara dust associated with global climate change. In 2022 unprecedented beach accumulations were reported from many Caribbean Islands and Florida. The shoreline topography at the northern end of VDMEJSP increases Sargassum deposition due to the presence of artificial jetties that trap eastward transported algae. This study documents extensive accumulations of Sargassum at this location and discusses impacts on local environments and associated organisms.
