Sargassum#Biological impacts

Sargassum was named by the Portuguese sailors who found it in the Sargasso Sea. They called it after the wooly rock rose (Halimium lasianthum) that grew in their water wells at home,{{citation needed|date=March 2023}} and that was called sargaço in Portuguese ({{IPA|pt|sɐɾˈɣasu}})Gómez de Silva, Guido 1988. Breve diccionario etimológico de la lengua española. Fondo de Cultura Económica, Mexico City, {{ISBN|968-16-2812-8}}, p. 627. - from the Latin salicastrum.

The Florida Keys and mainland South Florida are well known for the high levels of Sargassum covering their shores. Sargassum or gulfweed was observed by Columbus. Although the seaweed acquired a legendary reputation for covering the entirety of the Sargasso Sea, making navigation impossible,

{{cite book

|last1 = Padilla

|first1 = Michael J.

|author-link1 = Michael J. Padilla

|title = Earth's Waters

|year = 2000

|url = https://books.google.com/books?id=1kLczjA2ntAC

|publisher = Prentice Hall

|publication-date = 2000

|page = 114

|isbn = 9780134349404

|access-date = 11 July 2022

|quote = Since Columbus's time, many legends about the Sargasso Sea have spread. The seaweed covering its surface was believed to be so thick that no ship could escape from it. Early writers described ancient ghost ships, rotting away as they remained trapped forever in the seaweed.

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it has since been found to occur only in drifts.{{Cite web | url=http://bigstory.ap.org/article/f90d2fbf2d5d4d8e8f27cb5108fa8f05/stinking-mats-seaweed-piling-caribbean-beaches | title=Stinking mats of seaweed piling up on Caribbean beaches | author=David McFadden | date=August 10, 2015 | access-date=August 10, 2015 | archive-date=August 13, 2015 | archive-url=https://web.archive.org/web/20150813023438/http://bigstory.ap.org/article/f90d2fbf2d5d4d8e8f27cb5108fa8f05/stinking-mats-seaweed-piling-caribbean-beaches | url-status=dead }}

Sargassum species are cultivated and cleaned for use as an herbal remedy. Many Chinese herbalists prescribe powdered Sargassum—either the species S. pallidum, or more rarely, hijiki, S. fusiforme—in doses of 0.5 grams dissolved in warm water and drunk as a tea. It is called {{lang-zh|c=海藻|p=hǎizǎo|labels=no}} in traditional Chinese medicine, where it is used to resolve "heat phlegm".{{cite book|author=Xu Li & Wang Wei|title =Chinese Materia Medica: Combinations and Applications |publisher =Donica Publishing Ltd|year =2002|page=425|isbn =978-1-901149-02-9|url = https://books.google.com/books?id=36dhuXGm3OgC&q=Sargassum%20pallidum%20hai%20zao&pg=PA425}}

Sargassum (F. Sargassaceae) is an important seaweed excessively distributed in tropical and subtropical regions. Different species of Sargassum have folk applications in human nutrition and are considered a rich source of vitamins, carotenoids, proteins, and minerals. Many bioactive chemical compounds that are classified as terpenoids, sterols, sulfated polysaccharides, polyphenols, sargaquinoic acids, sargachromanol, and pheophytin were isolated from different Sargassum species. These isolated compounds and/or extracts exhibit diverse biological activities, including analgesic, anti-inflammatory, antioxidant, neuroprotective, anti-microbial, anti-tumor, fibrinolytic, immune-modulatory, anticoagulant, hepatoprotective, and anti-viral activities.{{Cite journal |last1=Rushdi |first1=Mohammed I. |last2=Abdel-Rahman |first2=Iman A. M. |last3=Saber |first3=Hani |last4=Attia |first4=Eman Zekry |last5=Abdelraheem |first5=Wedad M. |last6=Madkour |first6=Hashem A. |last7=Hassan |first7=Hossam M. |last8=Elmaidomy |first8=Abeer H. |last9=Abdelmohsen |first9=Usama Ramadan |date=2020 |title=Pharmacological and natural products diversity of the brown algae genus Sargassum |url=http://xlink.rsc.org/?DOI=D0RA03576A |journal=RSC Advances |language=en |volume=10 |issue=42 |pages=24951–24972 |doi=10.1039/D0RA03576A |issn=2046-2069 |pmc=9055232 |pmid=35517468|bibcode=2020RSCAd..1024951R }}

Image:Sargassum on the beach, Cuba.JPG

Image:CA0008920010107_Watercolour_illustration_of_Sargassum_seaweed_specimens_Plate_39_from_Seaweeds_of_New_Zealand_Te_Papa_832666_172981.jpg

{{Main|List of Sargassum species}}

Species of this genus of algae may grow to a length of several metres. They are generally brown or dark green in color and consist of a holdfast, a stipe, and a frond. Oogonia and antheridia occur in conceptacles embedded in receptacles on special branches.{{cite book |first1=Isabella A. |last1=Abbott |first2=George J. |last2=Hollenberg |chapter=Phaeophyta § Sargassum |title=Marine Algae of California |chapter-url=https://books.google.com/books?id=qYrx7i02uqsC&pg=PA272 |date=1992 |publisher=Stanford University Press |isbn=978-0-8047-2152-3 |pages=272–}} Some species have berrylike gas-filled bladders that help the fronds float to promote photosynthesis. Many have a rough, sticky texture that, along with a robust but flexible body, help them withstand strong water currents.

{{See also|Ocean surface ecosystem}}

Large, pelagic mats of Sargassum in the Sargasso Sea act as one of the only habitats available for ecosystem development; this is because the Sargasso Sea lacks any land boundaries.US Department of Commerce, National Oceanic and Atmospheric Administration. (2013, June 01). What is the Sargasso Sea? Retrieved November 28, 2017

[https://oceanservice.noaa.gov/facts/sargassosea.html] The Sargassum patches act as a refuge for many species in different parts of their development, but also as a permanent residence for endemic species that can only be found living on and within the Sargassum.Laffoley, D.d’A., Roe, H.S.J., Angel, M.V., Ardron, J., Bates, N.R., Boyd, I.L., Brooke, S., Buck, K.N., Carlson, C.A., Causey, B., Conte, M.H., Christiansen, S., Cleary, J., Donnelly, J., Earle, S.A., Edwards, R., Gjerde, K.M., Giovannoni, S.J., Gulick, S., Gollock, M., Hallett, J., Halpin, P., Hanel, R., Hemphill, A., Johnson, R.J., Knap, A.H., Lomas, M.W., McKenna, S.A., Miller, M.J., Miller, P.I., Ming, F.W., Moffitt, R., Nelson, N.B., Parson, L., Peters, A.J., Pitt, J., Rouja, P., Roberts, J., Roberts, J., Seigel, D.A., Siuda, A.N.S., Steinberg, D.K., Stevenson, A., Sumaila, V.R., Swartz, W., Thorrold, S., Trott, T.M., and V. Vats. (2011). The protection and management of the Sargasso Sea: The golden floating rainforest of the Atlantic Ocean. Summary Science and Supporting Evidence Case. Sargasso Sea Alliance, 44 pp. These endemic organisms have specialized patterns and colorations that mimic the Sargassum and allow them to be impressively camouflaged in their environment. In total, these Sargassum mats are home to more than 11 phyla and over 100 different species.{{cite journal |last1=Stoner |first1=AW |last2=Greening |first2=HS |title=Geographic variation in the macrofaunal associates of pelagic Sargassum and some biogeographic implications |journal=Marine Ecology Progress Series |date=1984 |volume=20 |pages=185–192 |doi=10.3354/meps020185 |bibcode=1984MEPS...20..185S |doi-access=free }} There is also a total of 81 fish species (36 families represented) that reside in the Sargassum or utilize it for parts of their life cycles.{{cite web |last1=Casazza |first1=T.L. |last2=Ross |first2=S.W. |title=Sargassum: A Complex 'Island' Community at Sea |url=https://oceanexplorer.noaa.gov/explorations/03edge/background/sargassum/sargassum.html |website=NOAA Ocean Explorer |access-date=27 September 2018}} Other marine organisms, such as young sea turtles, will use the Sargassum as shelter and a resource for food until they reach a size at which they can survive elsewhere. This community is being affected by humans due to overfishing, trash and other types of pollution, and boat traffic, which could eventually lead to the demise of this diverse and unique habitat. Below is a list of organisms that are associated with the Sargassum in the Sargasso Sea.

The Sargasso Sea plays a major role in the migration of catadromous eel species such as the European eel, the American eel, and the American conger eel. The larvae of these species hatch within the sea and as they grow they travel to Europe or the East Coast of North America. Later in life, the matured eel migrates back to the Sargasso Sea to spawn and lay eggs. It is also believed that after hatching, young loggerhead sea turtles use currents, such as the Gulf Stream, to travel to the Sargasso Sea, where they use the Sargassum as cover from predators until they are mature.{{Cite news| url=http://news.bbc.co.uk/1/hi/sci/tech/7477519.stm | work=BBC News | title=Turtles return home after UK stay | date=2008-06-30 | access-date=2010-05-23}}{{Cite news| url=https://www.bbc.com/news/science-environment-26435342 | work=BBC News | title=Satellites track turtle 'lost years' | date=2014-03-05 | access-date=2014-03-05}}

Sargassum also serve as a trophic link between the ocean surface and the seabed. Isopods of the species Bathyopsurus nybelini at depths of 5002–6288 m in the Puerto Rico Trench and Mid-Cayman spreading center have been observed consuming Sargassum. They even exhibit several adaptations for it, such as microbiomes capable of breaking down the seaweed and fixing nitrogen, specialized swimming strokes, and serrated, grinding mouthparts.{{Cite journal |last1=Peoples |first1=Logan M. |last2=Gerringer |first2=Mackenzie E. |last3=Weston |first3=Johanna N. J. |last4=León-Zayas |first4=Rosa |last5=Sekarore |first5=Abisage |last6=Sheehan |first6=Grace |last7=Church |first7=Matthew J. |last8=Michel |first8=Anna P. M. |last9=Soule |first9=S. Adam |last10=Shank |first10=Timothy M. |date=2024-09-11 |title=A deep-sea isopod that consumes Sargassum sinking from the ocean's surface |journal=Proceedings of the Royal Society B: Biological Sciences |language=en |volume=291 |issue=2030 |doi=10.1098/rspb.2024.0823 |pmid=39255840 |issn=0962-8452 |pmc=11387067}}

Organisms found in the pelagic Sargassum patches,{{Cite web|title=NOAA Ocean Explorer: Life on the Edge: Sargassum|url=https://oceanexplorer.noaa.gov/explorations/03edge/background/sargassum/sargassum.html|access-date=2021-11-22|website=oceanexplorer.noaa.gov}}{{cite journal |last1=Huffard |first1=C. L. |last2=von Thun |first2=S. |last3=Sherman |first3=A. D. |last4=Sealey |first4=K. |last5=Smith |first5=K. L. |title=Pelagic Sargassum community change over a 40-year period: temporal and spatial variability |journal=Marine Biology |date=December 2014 |volume=161 |issue=12 |pages=2735–2751 |doi=10.1007/s00227-014-2539-y |pmid=25414525 |pmc=4231207 |bibcode=2014MarBi.161.2735H }}

• Arthropods
• Amphipods
• Skeleton shrimp
• Crabs
• Copepods
• Shrimp
• Sea Spiders
• Worms
• Annelid worms
• Flatworms
• Mollusks
• Nudibranchs
• Snails
• Squid
• Fish
• Sargassum fish
• Porcupinefish
• Triplefin
• Planehead filefish
• European eel
• American eel
• American conger eel
• Others
• Sea turtles

Sargassum is commonly found in the beach drift near Sargassum beds, where they are also known as gulfweed, a term that also can mean all seaweed species washed up on shore.

Sargassum species are found throughout tropical areas of the world and are often the most obvious macrophyte in near-shore areas where Sargassum beds often occur near coral reefs. The plants grow subtidally and attach to coral, rocks, or shells in moderately exposed or sheltered rocky or pebble areas. These tropical populations often undergo seasonal cycles of growth and decay in concert with seasonal changes in sea temperature.{{cite journal |vauthors=Fulton CJ, Depczynski M, Holmes TH, Noble MM, Radford B, Wernberg TH, Wilson SK |title=Sea temperature shapes seasonal fluctuations in seaweed biomass within the Ningaloo coral reef ecosystem |journal=Limnology & Oceanography |volume=59 |issue=1 |pages=156–166 |year=2014 |doi=10.4319/lo.2014.59.1.0156 |bibcode=2014LimOc..59..156F |url=http://ningaloo-atlas.org.au/content/sea-temperature-drives-seasonal-cycles-ningaloo-seaw|doi-access=free }}

In tropical Sargassum species that are often preferentially consumed by herbivorous fishes and echinoids, a relatively low level of phenolics and tannins occurs.{{cite journal |first=Peter D. |last=Steinberg |title=Chemical defenses and the susceptibility of tropical marine brown algae to herbivores |journal=Oecologia |volume=69 |issue=4 |pages=628–630 |year=1986 |doi=10.1007/BF00410374 |pmid=28311627 |bibcode=1986Oecol..69..628S |s2cid=19551247 }}

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| footer = The camouflaged Sargassum fish (left) has adapted to live among drifting Sargassum seaweed. It is usually a small fish (center).
Some other small fish, such as this juvenile puffer (right), are also found in Sargassum.

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File:Sargasses au large de Tintamare- RNN de Saint Martin.jpg.]]

In limited amounts, washed-ashore Sargassum plays an important role in maintaining Atlantic and Caribbean coastal ecosystems.{{Cite web|url=https://bvi.gov.vg/media-centre/sargassum-seaweed-important-element-beaches-and-shoreline-stability|title=Sargassum Seaweed: An important element for beaches and shoreline stability. | Government of the Virgin Islands|website=bvi.gov.vg}} Once ashore, Sargassum provides vital nutrients such as carbon, nitrogen, and phosphorus to coastal ecosystems which border the nutrient-poor waters of the western North Atlantic tropics and subtropics.{{Cite book|url=https://www.nap.edu/read/2049/chapter/9|title=Read "Managing Wastewater in Coastal Urban Areas" at NAP.edu|year=1993|doi=10.17226/2049|isbn=978-0-309-04826-2|via=www.nap.edu}}{{Cite news|url=https://www.reuters.com/article/us-health-travel-toxic-seaweed-idUSKCN1UL1ZG|title=Toxic seaweed a menace to Caribbean tourists|first=Carolyn|last=Crist|newspaper=Reuters|date=July 26, 2019|via=www.reuters.com}} Additionally, it decreases coastal erosion.

Beginning in 2011, unprecedented quantities of Sargassum began inundating coastal areas in record amounts.{{Cite journal|url=https://tos.org/oceanography/article/recent-sargassum-inundation-events-in-the-caribbean-shipboard-observations|title=Recent Sargassum Inundation Events in the Caribbean: Shipboard Observations Reveal Dominance of a Previously Rare Form|first1=Jeffrey|last1=Schell|first2=Deborah|last2=Goodwin|first3=Amy|last3=Siuda|date=September 1, 2015|journal=Oceanography|volume=28|issue=3|pages=8–10|doi=10.5670/oceanog.2015.70|doi-access=free}} Coastlines in Brazil, the Caribbean, Gulf of Mexico, and the east coast of Florida saw quantities of Sargassum wash ashore up to three feet deep.{{cite web |url=https://www.nps.gov/viis/learn/nature/upload/gcfisargassumfactsheet_2015-1.pdf |archive-url=https://web.archive.org/web/20170217034059/https://www.nps.gov/viis/learn/nature/upload/gcfisargassumfactsheet_2015-1.pdf |url-status=dead |archive-date=February 17, 2017 |title= Fact sheet |website=www.nps.gov |access-date=2020-09-29}} The first major Sargassum inundation event occurred in 2011 and had a biomass increase of 200 fold compared to the previous eight years average bloom size.{{Cite web|url=https://essa.com/the-great-sargassum-disaster-of-2018/|title=The Great Sargassum Disaster of 2018 |work=essa.com |date=February 7, 2019}} Since 2011 increasingly stronger inundation events have occurred every 2–3 years. During a Sargassum inundation event in 2018, one Sargassum bloom measured over 1600 square kilometers, more than three times the average size.{{Cite web|url=https://nereusprogram.org/works/the-sargassum-mass-bloom-of-2018/|title=The Sargassum Mass-Bloom of 2018 |work=nereusprogram.org}} Recent inundation events have caused millions of dollars of lost revenue in the tourism industry, especially hurting small Caribbean countries whose economies are highly dependent on seasonal tourism.

While the Sargasso Sea is a known source of Sargassum blooms, variations in the Sargassum types composing these inundation events have led researchers to believe that the Sargasso Sea is not the point of origin of inundating Sargassum.{{Cite journal|jstor = 24861895|title = Recent Sargassum Inundation Events in the Caribbean|last1 = Schell|first1 = Jeffrey M.|last2 = Goodwin|first2 = Deborah S.|last3 = Siuda|first3 = Amy N. S.|journal = Oceanography|year = 2015|volume = 28|issue = 3|pages = 8–11|doi = 10.5670/oceanog.2015.70|doi-access = free}} Sargassum natans I and Sargassum fluitans III are the dominant Sargassum species found in the Sargasso Sea.{{cite journal |last1=Schell |first1=Jeffrey |last2=Goodwin |first2=Deborah |last3=Siuda |first3=Amy |title=Recent Sargassum Inundation Events in the Caribbean: Shipboard Observations Reveal Dominance of a Previously Rare Form |journal=Oceanography |date=1 September 2015 |volume=28 |issue=3 |pages=8–10 |doi=10.5670/oceanog.2015.70|doi-access=free }} Recent net sampling studies have found Sargassum natans VIII, a previously rare type, is constituting a dominating percentage of Sargassum biodiversity in the Western Atlantic and Sargasso Sea.{{cite thesis |last1=Martin |first1=Lindsay Margaret |title=Pelagic Sargassum and Its Associated Mobile Fauna in the Caribbean, Gulf Of Mexico, and Sargasso Sea |date=6 May 2016 |hdl=1969.1/157125 }}{{Cite web|date=2018-06-15|title=Ramlogan et al 2017 sargassum influx barbados fish |url=http://www.cavehill.uwi.edu/cermes/getdoc/ceecd5b8-2111-4fc9-b481-9b18d9e785bd/ramlogan_et_al_2017_sargassum_influx_barbados_fish.aspx|access-date=2021-11-22|archive-url=https://web.archive.org/web/20180615125922/http://www.cavehill.uwi.edu/cermes/getdoc/ceecd5b8-2111-4fc9-b481-9b18d9e785bd/ramlogan_et_al_2017_sargassum_influx_barbados_fish.aspx|archive-date=2018-06-15}}

Unprecedented Sargassum inundation events cause a range of biological and ecological impacts in affected regions. The decomposition of large quantities of Sargassum along coastlines consumes oxygen, creating large oxygen-depleted zones resulting in fish kills.{{cite web | last=Burton | first=Rebecca | title=Sargassum: Seaweed or Brown Algae | website=Florida Museum | date=2018-07-15 | url=https://www.floridamuseum.ufl.edu/earth-systems/blog/sargassum-seaweed-or-brown-algae/ | access-date=2020-09-29}} Decomposing Sargassum additionally creates hydrogen sulfide gas ({{Chem2|H2S|link=Hydrogen sulfide}}), which causes a range of health impacts in humans.{{cite web | title=Sargassum seaweed: limit the exposure of residents and workers to hydrogen sulphide - Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail | website=Anses | date=9 November 2018 | url=https://www.anses.fr/en/content/sargassum-seaweed-limit-exposure-residents-and-workers-hydrogen-sulphide | access-date=2020-09-29}} During the Sargassum inundation event in 2018, 11,000 Acute Sargassum Toxicity cases were reported in an 8-month span on just the Caribbean islands of Guadeloupe and Martinique.{{cite web | last=Crist | first=Carolyn | title=Toxic seaweed a menace to Caribbean tourists | website=U.S. | date=2019-07-26 | url=https://www.reuters.com/article/us-health-travel-toxic-seaweed-idUSKCN1UL1ZG | access-date=2020-09-29}} Massive amounts of floating Sargassum present a physical barrier preventing corals and seagrasses from receiving sufficient light, fouling boat propellers, and entangling marine turtles and mammals.{{cite web | title=Tracking Sargassum's ocean path could help predict coastal inundation events | website=University of Maryland Center for Environmental Science | date=2018-08-22 | url=https://www.umces.edu/content/tracking-sargassum%E2%80%99s-ocean-path-could-help-predict-coastal-inundation-events | access-date=2020-09-29}}{{cite web | title=The Great Sargassum Disaster of 2018 | website=ESSA | date=2019-02-07 | url=https://essa.com/the-great-sargassum-disaster-of-2018/ | access-date=2020-09-29}} With every Sargassum inundation event, large amounts of nutrients are transported from the open ocean to coastal environments. This greatly increases nutrient transport, and its effect on marine and coastal ecosystems are still unknown. Understanding the causes and drivers of Sargassum inundations is critical as they become more commonplace.{{cite journal |last1= Smetacek |first1=Victor |last2=Zingone |first2= Adriana |title=Green and golden seaweed tides on the rise |journal=Nature |date=2013 |volume=504 |issue=7478 |pages=84–88 |doi=10.1038/nature12860|pmid=24305152 |bibcode=2013Natur.504...84S |s2cid=4389919 |url=https://epic.awi.de/id/eprint/35158/1/nature12860.pdf }}

The Sargasso Sea, a known source area for Sargassum blooms, is classified as an oligotrophic region.{{cite journal |last1=Lundgreen |first1=Regitze B. C. |last2=Jaspers |first2=Cornelia |last3=Traving |first3=Sachia J. |last4=Ayala |first4=Daniel J. |last5=Lombard |first5=Fabien |last6=Grossart |first6=Hans-Peter |last7=Nielsen |first7=Torkel G. |last8=Munk |first8=Peter |last9=Riemann |first9=Lasse |title=Eukaryotic and cyanobacterial communities associated with marine snow particles in the oligotrophic Sargasso Sea |journal=Scientific Reports |date=20 June 2019 |volume=9 |issue=1 |pages=8891 |doi=10.1038/s41598-019-45146-7 |pmid=31222051 |pmc=6586830 |bibcode=2019NatSR...9.8891L }} With warm, oxygen-poor waters and low nutrient contents, biomass production is limited by what little nutrients are present.{{Cite web|url=http://www.sargassoseacommission.org/about-the-sargasso-sea/functionality-of-world-ocean|title=Functionality of World Ocean|first=Faith|last=Bulger|website=Sargasso Sea Commission}} Historically, low nutrient levels in the Sargasso Sea have limited Sargassum production. New influxes of nitrogen and phosphorus are driving factors in increased biomass production.{{Cite web|url=https://eos.org/articles/satellite-data-reveal-growth-and-decline-of-sargassum|title=Satellite Data Reveal Growth and Decline of Sargassum|website=Eos|date=29 July 2019}}{{cite web | last=Kornei | first=Katherine | title=Satellite Data Reveal Growth and Decline of Sargassum | website=Eos | date=2019-07-29 | url=https://eos.org/articles/satellite-data-reveal-growth-and-decline-of-sargassum | access-date=2020-09-29}}{{cite journal |last1=Lapointe |first1=Brian E. |title=A comparison of nutrient-limited productivity in Sargassum natans from neritic vs. oceanic waters of the western North Atlantic Ocean |journal=Limnology and Oceanography |date=1995 |volume=40 |issue=3 |pages=625–633 |doi=10.4319/lo.1995.40.3.0625 |bibcode=1995LimOc..40..625L |doi-access=free }}

Recent studies have found three likely drivers of nutrient influx linked to increasing Sargassum biomass: an increase in nutrient output from the Amazon River, increased nutrients in the Gulf of Mexico, and coastal upwelling off the West African Coast which transfers deep nutrient-rich waters to the upper water column where Sargassum resides.{{Cite web|url=https://phys.org/news/2019-07-scientists-biggest-seaweed-bloom-world.html|title=Scientists discover the biggest seaweed bloom in the world|website=phys.org}}{{Cite web|url=https://www.sciencedaily.com/releases/2018/08/180823092013.htm|title=Tracking Sargassum's ocean path could help predict coastal inundation events|website=ScienceDaily}} Nutrient output from the Amazon River has been shown to have a direct delayed effect on large inundation events, which occur one to two years after years of high nutrient output. Phosphates and iron transported via the trade winds from North Africa have been reported to have a fertilizing effect on Sargassum growth; further data is required to understand its role in causing inundating blooms. Researchers globally agree that continued research is required to quantify the effect of marine chemical changes and other environmental factors in the recent increase in Sargassum biomass and inundation events.

The physical drivers behind Sargassum inundation events are prevailing winds and ocean surface currents.{{Cite web|url=https://phys.org/news/2018-08-tracking-sargassum-ocean-path-coastal.html|title=Tracking Sargassum's ocean path could help predict coastal inundation events|website=phys.org}} The Caribbean is located in a region heavily affected by Trade winds. Trade winds are strong, consistent northeasterlies winds which blow dust-filled dry air from the Sahara across the Atlantic.{{Cite web|url=https://www.scientificamerican.com/article/saharan-dust-plume-slams-u-s-kicking-up-climate-questions/|title=Saharan Dust Plume Slams U.S., Kicking Up Climate Questions|first=Chelsea |last=Harvey|website=Scientific American}} Trade winds additionally play a critical role in the annual hurricane season in the Western Atlantic.{{Cite web|url=http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/hurr/mvmt.rxml|title=Movement of Hurricanes: steered by the global winds|website=ww2010.atmos.uiuc.edu}} The Caribbean Current and Antilles branch of the Atlantic North Equatorial Current are the major current transporters of Sargassum in the region.{{Cite web|url=https://www.britannica.com/place/Antilles-Current|title=Antilles Current | current, Atlantic Ocean|website=Encyclopedia Britannica}}{{Cite web|url=https://oceancurrents.rsmas.miami.edu/caribbean/caribbean.html |title = The Caribbean Current |work=oceancurrents.rsmas.miami.edu}}

Researchers have recently begun using Moderate Resolution Imaging Spectroradiometer satellite imagery and ocean current data to track and forecast inundation events with a high level of accuracy.{{cite journal |last1=Wang |first1=Mengqiu |last2=Hu |first2=Chuanmin |title=Predicting Sargassum blooms in the Caribbean Sea from MODIS observations: Sargassum Bloom Prediction |journal=Geophysical Research Letters |date=16 April 2017 |volume=44 |issue=7 |pages=3265–3273 |doi=10.1002/2017GL072932 |doi-access=free }}

The effects of deforestation, waste-water runoff, and commercial agriculture fertilizer on facilitating the excess accumulation of nutrients in aquatic and marine environments have been well studied and shown to be driving factors in eutrophication.{{cite web |url=https://www.geo.arizona.edu/nyanza/pdf/Lombardozzi.pdf |title=The Effects of Deforestation on Nutrient Concentrations in Tributaries of Lake Tanganyika |website=www.geo.arizona.edu |access-date=2020-09-29}}{{Cite web|url=https://www.epa.gov/nutrientpollution/sources-and-solutions-agriculture|title=The Sources and Solutions: Agriculture|first=OW|last=US EPA|date=March 12, 2013|website=US EPA}} Since detrimental Sargassum inundation events did not begin until 2011, it is likely that an unknown nutrient threshold was reached and surpassed. Given current agricultural policies and practices, it is unlikely these inundation events will disappear on their own without human intervention.

Japanese cuisine as well as Chile have traditionally consumed Sargassum, known as hijiki, although it contains high amounts of arsenic, part of the arsenic cycle from groundwater, waterways, into oceans and back to land. There are [https://www.sciencedirect.com/science/article/abs/pii/S0045653521038832 methods] to process and greatly reduce arsenic from this genus of seaweed, potentially making it a nearly inexhaustible food supply for animals or people.

Variations in sea level, salinity, water temperature, chemical composition, rainfall patterns, and water acidity all play roles in regulating algae blooms.{{Cite web|url=https://www.epa.gov/nutrientpollution/climate-change-and-harmful-algal-blooms|title=Climate Change and Harmful Algal Blooms|first=OW|last=US EPA|date=September 5, 2013|website=US EPA}} As anthropogenic forces increase the variability of these factors, the frequency, duration, severity and geographic range of harmful algae blooms have increased, causing millions of dollars of lost revenue as well as damaging fragile coastal and coral ecosystems.{{cite web |url=https://www.epa.gov/sites/production/files/documents/climatehabs.pdf |title=Impacts of Climate Change on the Occurrence of Harmful Algal Blooms |date=2013 |website=www.epa.gov |access-date=2020-09-29}}

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• {{cite journal |last1=Critchley |first1=A.T. |last2=Farnham |first2=W.F. |last3=Morrell |first3=S.L. |title=A chronology of new European sites of attachment for the invasive brown alga, Sargassum muticum, 1973–1981 |journal=Journal of the Marine Biological Association of the United Kingdom |volume=63 |issue=1 |pages=799–811 |year=1983 |doi=10.1017/S0025315400071228 |bibcode=1983JMBUK..63..799C |s2cid=84790037 }}
• {{cite journal |last1=Boaden |first1=P. J. S. |title=The Adventive Seaweed Sargassum muticum (Yendo) Fensholt in Strangford Lough, Northern Ireland |journal=The Irish Naturalists' Journal |date=1995 |volume=25 |issue=3 |pages=111–113 |jstor=25535928 }}
• {{cite journal |first=D.M. |last=Davison |title=Sargassum muticum in Strangford Lough, 1995–1998; a review of the introduction and colonisation of Strangford Lough MNR and cSAC by the invasive brown alga Sargassum muticum |journal=Environment and Heritage Service Research and Development Series |issue=99 |pages=27 |year=1999 |issn=1367-1979}}
• {{Cite web |title=The real story behind the Atlantic's record-breaking seaweed blobs |last=Griffiths |first=Sarah |work=bbc.com |date=28 June 2023 |access-date=3 July 2023 |url= https://www.bbc.com/future/article/20230622-what-is-causing-the-atlantics-seaweed-blobs}}

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{{Commons category|Sargassum}}

{{Wiktionary|Sargassum|sargasso}}

{{Americana Poster|year=1920}}

• [http://www.algaebase.org/search/species/detail/?species_id=90 algaebase.org]
• [http://www.seaweed.ie/sargassum/ seaweed.ie]
• [http://www.marlin.ac.uk/species/Sargassummuticum.htm marlin.ac.uk] {{Webarchive|url=https://web.archive.org/web/20180501072823/http://www.marlin.ac.uk/species/Sargassummuticum.htm |date=2018-05-01 }}
• [https://web.archive.org/web/20050905154458/http://www.surialink.com/HANDBOOK/Genera/browns/Sargassum/Sargassum.htm The SuriaLink Seaplants Handbook – Sargassum]
• [https://web.archive.org/web/20070610203506/http://www.mbari.org/staff/conn/botany/browns/jacquie/repro.htm Sargassum reproduction.]
• [https://oceanservice.noaa.gov/facts/sargassosea.html What is the Sargasso Sea?] US Department of Commerce, National Oceanic and Atmospheric Administration. (2013, June 1).

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Category:Edible algae

Category:Fucales

Category:Fucales genera

Category:Marine biota of North America