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49-528: The Great Atlantic Sargassum Belt is a mass of Sargassum in the Atlantic Ocean , and is the largest macroalgae bloom in the world. This Sargassum was first reported by Christopher Columbus in the 15th century but recently appeared in 2011 in the Atlantic. As of 2023, the belt is estimated to weigh about 5.5 million metric tonnes and extends 5,000 miles (8,000 km), stretching from West Africa to

98-421: A planktonic , often pelagic existence after being removed from reefs during rough weather. Two species ( S. natans and S. fluitans ) have become holopelagic—reproducing vegetatively and never attaching to the seafloor during their lifecycles. The Atlantic Ocean 's Sargasso Sea was named after the algae, as it hosts a large amount of Sargassum . The size of annual blooms in the Atlantic increased by over

147-602: A hundred-fold, starting in 2011, as a result of factors including increased fertilizer runoff in major rivers such as the Amazon and Congo . 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, and that was called sargaço in Portuguese ( Portuguese pronunciation: [sɐɾˈɣasu] ) - from

196-497: 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. 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. Large, pelagic mats of Sargassum in

245-534: 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 . 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. Congo River Measured along with

294-531: 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. Decomposing Sargassum additionally creates hydrogen sulfide gas ( H 2 S ), which causes a range of health impacts in humans. During the Sargassum inundation event in 2018, 11,000 Acute Sargassum Toxicity cases were reported in an 8-month span on just

343-635: A relatively low level of phenolics and tannins occurs. In limited amounts, washed-ashore Sargassum plays an important role in maintaining Atlantic and Caribbean coastal ecosystems. 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. Additionally, it decreases coastal erosion . Beginning in 2011, unprecedented quantities of Sargassum began inundating coastal areas in record amounts. Coastlines in Brazil ,

392-464: 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

441-640: 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. Species of this genus of algae may grow to

490-3986: Is in the Ruwenzori Mountains , at an altitude of around 4,340 m (14,240 ft) above sea level. Distribution of the Congo basin area between countries: The most important hydrological stations along the Congo River are: Brazzaville The Congo River discharge at Kinshasa / Brazzaville stations since the start of measurements (1902 to 2021): 5°08′30.4″S 13°59′27.9″E  /  5.141778°S 13.991083°E  / -5.141778; 13.991083 5°02′57.3″S 13°59′28.2″E  /  5.049250°S 13.991167°E  / -5.049250; 13.991167 5°01′49.5″S 14°01′37.2″E  /  5.030417°S 14.027000°E  / -5.030417; 14.027000 5°2′20.6″S 14°02′09.2″E  /  5.039056°S 14.035889°E  / -5.039056; 14.035889 4°56′50.7″S 14°09′21.2″E  /  4.947417°S 14.155889°E  / -4.947417; 14.155889 4°55′38.5″S 14°15′16.5″E  /  4.927361°S 14.254583°E  / -4.927361; 14.254583 4°54′03.3″S 14°24′18.2″E  /  4.900917°S 14.405056°E  / -4.900917; 14.405056 Brazzaville 4°16′47.3″S 15°18′32.8″E  /  4.279806°S 15.309111°E  / -4.279806; 15.309111 4°05′24.4″S 15°30′39.1″E  /  4.090111°S 15.510861°E  / -4.090111; 15.510861 3°52′43.4″S 15°55′11.6″E  /  3.878722°S 15.919889°E  / -3.878722; 15.919889 3°33′18.7″S 16°05′32.2″E  /  3.555194°S 16.092278°E  / -3.555194; 16.092278 3°28′52.5″S 16°07′18.3″E  /  3.481250°S 16.121750°E  / -3.481250; 16.121750 3°11′23.7″S 16°11′09.6″E  /  3.189917°S 16.186000°E  / -3.189917; 16.186000 3°10′36.4″S 16°11′41.5″E  /  3.176778°S 16.194861°E  / -3.176778; 16.194861 3°09′59.7″S 16°10′51.7″E  /  3.166583°S 16.181028°E  / -3.166583; 16.181028 2°48′33.9″S 16°11′40.1″E  /  2.809417°S 16.194472°E  / -2.809417; 16.194472 2°12′22.9″S 16°10′49.0″E  /  2.206361°S 16.180278°E  / -2.206361; 16.180278 2°09′28.5″S 16°12′16.5″E  /  2.157917°S 16.204583°E  / -2.157917; 16.204583 1°52′15.5″S 16°30′43.4″E  /  1.870972°S 16.512056°E  / -1.870972; 16.512056 1°37′55.5″S 16°37′59.4″E  /  1.632083°S 16.633167°E  / -1.632083; 16.633167 1°14′22.2″S 16°47′44.5″E  /  1.239500°S 16.795694°E  / -1.239500; 16.795694 1°03′13.5″S 17°08′58.0″E  /  1.053750°S 17.149444°E  / -1.053750; 17.149444 0°54′39.2″S 17°23′27.1″E  /  0.910889°S 17.390861°E  / -0.910889; 17.390861 0°43′38.5″S 17°33′02.9″E  /  0.727361°S 17.550806°E  / -0.727361; 17.550806 0°41′00.4″S 17°36′43.7″E  /  0.683444°S 17.612139°E  / -0.683444; 17.612139 0°25′58.1″S 17°50′13.3″E  /  0.432806°S 17.837028°E  / -0.432806; 17.837028 0°01′17.4″N 18°13′10.9″E  /  0.021500°N 18.219694°E  / 0.021500; 18.219694 0°30′22.1″N 25°11′03.4″E  /  0.506139°N 25.184278°E  / 0.506139; 25.184278 The main river and tributaries are (sorted in order from

539-559: 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 methods to process and greatly reduce arsenic from this genus of seaweed, potentially making it

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588-613: 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. Trade winds additionally play a critical role in the annual hurricane season in the Western Atlantic. The Caribbean Current and Antilles branch of the Atlantic North Equatorial Current are the major current transporters of Sargassum in

637-423: Is not the point of origin of inundating Sargassum . Sargassum natans I and Sargassum fluitans III are the dominant Sargassum species found in the Sargasso Sea. 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. Unprecedented Sargassum inundation events cause

686-519: Is the preferred English name in 19th-century literature, although references to Zahir or Zaire as the name used by the inhabitants remained common. The Democratic Republic of the Congo and the Republic of the Congo are named after it, as was the previous Republic of the Congo which had gained independence in 1960 from the Belgian Congo . The Republic of Zaire during 1971–1997 was also named after

735-653: 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. 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

784-557: The Atlantic Ocean and an additional 6% of bedload . The river and its tributaries flow through the Congo rainforest , the second largest rainforest area in the world, after the Amazon rainforest in South America. The river also has the second-largest flow in the world, behind the Amazon ; the second-largest drainage basin of any river, behind the Amazon; and is one of the deepest rivers in

833-556: The Caribbean , Gulf of Mexico , and the east coast of Florida saw quantities of Sargassum wash ashore up to three feet deep. 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. 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

882-596: The Gulf Stream , to travel to the Sargasso Sea, where they use the Sargassum as cover from predators until they are mature. 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

931-481: The Gulf of Mexico . “I try to shy away from the term blob. That’s not really what it is,” says Barnes, who says that the Great Atlantic Sargassum Belt is really a series of many small blobs with individual patches that are as large as an acre. Smushed together, he adds, it would be roughly the size of Delaware . Due to the smell, the attracted insects, and the sheer amount of it piling up on beaches,

980-560: The Inga dams , about 200 kilometres (120 mi) southwest of Kinshasa. The project was launched in the early 1970s, when the first dam was completed. The plan (as originally conceived) called for the construction of five dams that would have had a total generating capacity of 34,500 megawatts (MW). To date only the Inga I and Inga II dams have been built, generating 1,776 MW. In February 2005, South Africa 's state-owned power company, Eskom , announced

1029-560: The Pool Malebo (Stanley Pool). Kinshasa (formerly Léopoldville) and Brazzaville are on opposite sides of the river at the Pool, where the river narrows and falls through a number of cataracts in deep canyons (collectively known as the Livingstone Falls ), running by Matadi and Boma , and into the sea at Muanda . Lower Congo constitutes the "lower" parts of the great river; that is

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1078-417: 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. 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. Other marine organisms, such as young sea turtles, will use the Sargassum as shelter and

1127-506: The Uíge Province in Angola to the confluence with the Congo at Zongo some 80 km (50 mi) downstream from the twin capitals. Because of the vast number of rapids, in particular the Livingstone Falls , this section of the river is not operated continuously by riverboats. The Congo basin covers ten countries and accounts for about 13% of Africa . The highest point in the Congo basin

1176-588: 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

1225-520: The Atlantic Ocean. Opportunities for the Congo River and its tributaries to generate hydropower are therefore enormous. Scientists have calculated that the entire Congo Basin accounts for 13 percent of global hydropower potential. This would provide sufficient power for all of Sub-Saharan Africa 's electricity needs. Currently, there are about 40 hydropower plants in the Congo Basin. The largest are

1274-570: The Caribbean islands of Guadeloupe and Martinique . 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. 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

1323-624: The Congo below Boyoma Falls . The Chambeshi River in Zambia is generally taken as the source of the Congo in line with the accepted practice worldwide of using the longest tributary, as with the Nile River. The Congo flows generally toward the northwest from Kisangani just below the Boyoma Falls, then gradually bends southwestward, passing by Mbandaka , joining with the Ubangi River and running into

1372-498: The Kongo people or Bakongo was introduced in the early 20th century. The name Zaire is from a Portuguese adaptation of a Kikongo word, nzere ("river"), a truncation of nzadi o nzere ("river swallowing rivers"). The river was known as Zaire during the 16th and 17th centuries; Congo seems to have replaced Zaire gradually in English usage during the 18th century, and Congo

1421-568: 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, it has since been found to occur only in drifts. Sargassum species are cultivated and cleaned for use as an herbal remedy. Many Chinese herbalists prescribe powdered Sargassum —either

1470-570: The Lualaba, the main tributary, the Congo River has a total length of 4,370 km (2,720 mi). It is the only major river to cross the Equator twice. The Congo Basin has a total area of about 4,000,000 km (1,500,000 sq mi), or 13% of the entire African landmass. The name Congo/Kongo originates from the Kingdom of Kongo once located on the southern bank of the river. The kingdom in turn

1519-439: The Sargasso Sea act as one of the only habitats available for ecosystem development; this is because the Sargasso Sea lacks any land boundaries. 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 . These endemic organisms have specialized patterns and colorations that mimic

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1568-592: The Sargasso Sea and is mainly composed of more highly nutrient-efficient organisms. The Sargassum Belt forms in the North Atlantic Gyre as currents push the material into one mass, similar to the North Atlantic garbage patch . Sargassum See list Sargassum is a genus of brown macroalgae ( seaweed ) in the order Fucales of the Phaeophyceae class. Numerous species are distributed throughout

1617-458: The Sargassum Belt has a negative impact on communities in the Caribbean, and West Africa. When the Sargassum dies after about 48 hours on land, it releases hydrogen sulfide , a toxic gas. The sulfide can irritate eyes, nose and throat and has a smell akin to that of rotting eggs. The sulfide also can affect people with respiratory problems, including asthma. In 2022, the largest bloom on record

1666-401: The algae, risking both wildlife and humans. The buildup of Sargassum is caused by nutrients flowing into the Atlantic from water discharged by the Amazon and upwelling currents off West Africa. The Sargassum Belt, while in the Sargasso Sea , is different, composed of different morphological types of Sargassum . The Sargassum Belt has also been found to possess lower biodiversity than

1715-411: The average size. 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

1764-670: The causes and drivers of Sargassum inundations is critical as they become more commonplace. The Sargasso Sea, a known source area for Sargassum blooms, is classified as an oligotrophic region. With warm, oxygen-poor waters and low nutrient contents, biomass production is limited by what little nutrients are present. 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. Recent studies have found three likely drivers of nutrient influx linked to increasing Sargassum biomass: an increase in nutrient output from

1813-472: 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. In tropical Sargassum species that are often preferentially consumed by herbivorous fishes and echinoids ,

1862-597: The mouth heading upstream): Lower Congo (river mouth to Kinshasa ) Downstream of Kinshasa, from the river mouth at Banana , there are a few major tributaries. Middle Congo ( Kinshasa to the Boyoma Falls ) Upper Congo ( Lualaba ; upstream from the Boyoma Falls ) Although the Livingstone Falls prevent access from the sea, nearly the entire Congo above them is readily navigable in sections, especially between Kinshasa and Kisangani. Large river steamers worked

1911-558: The region. 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. 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 . Since detrimental Sargassum inundation events did not begin until 2011, it

1960-506: The river until quite recently. The Congo River still is a lifeline in a land with few roads or railways. Railways now bypass the three major falls, and much of the trade of Central Africa passes along the river, including copper , palm oil (as kernels), sugar , coffee , and cotton . The Congo River is the most powerful river in Africa. During the rainy season over 50,000 cubic metres (1,800,000 cu ft) of water per second flows into

2009-552: The river's name in French and Portuguese . The Congo's drainage basin covers 4,014,500 km (1,550,000 sq mi), an area nearly equal to that of the European Union . The Congo's discharge at its mouth ranges from 23,000 to 75,000 m /s (810,000 to 2,650,000 cu ft/s), with an average of 41,000 m /s (1,400,000 cu ft/s). The river transports annually 86 million tonnes of suspended sediment to

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2058-421: The seaweed and fixing nitrogen, specialized swimming strokes, and serrated, grinding mouthparts. Organisms found in the pelagic Sargassum patches, 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

2107-576: The section of the river from the river mouth at the Atlantic coast to the twin capitals of Brazzaville and Kinshasa. In this section of the river, there are two significant tributaries, both on the left or south side. The Kwilu River originates in the hills near the Angolan border and enters the Congo some 100 km upstream from Matadi . The other is the Inkisi River , that flows in a northerly direction from

2156-457: 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 海藻 ; hǎizǎo in traditional Chinese medicine , where it is used to resolve "heat phlegm". 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

2205-416: The temperate and tropical oceans of the world, where they generally inhabit shallow water and coral reefs, and the genus is widely known for its planktonic (free-floating) species. Most species within the class Phaeophyceae are predominantly cold-water organisms that benefit from nutrients upwelling, but the genus Sargassum appears to be an exception. Any number of the normally benthic species may take on

2254-524: 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. The Caribbean

2303-546: The world, at depths greater than 220 m (720 ft). Because its drainage basin includes areas both north and south of the Equator , its flow is stable, as there is always at least one part of the river experiencing a rainy season . The sources of the Congo are in the highlands and mountains of the East African Rift , as well as Lake Tanganyika and Lake Mweru , which feed the Lualaba River , which then becomes

2352-513: Was named after the indigenous Bantu Kongo people , known in the 17th century as "Esikongo". South of the Kingdom of Kongo proper lay the similarly named Kakongo kingdom, mentioned in 1535. Abraham Ortelius labelled "Manicongo" as the city at the mouth of the river in his world map of 1564. The tribal names in Kongo possibly derive from a word for a public gathering or tribal assembly. The modern name of

2401-630: Was recorded, causing Guadeloupe to issue a health alert, as well as the US Virgin Islands issuing a state of emergency, requesting help from FEMA . By June 2023 clumps of Sargassum had begun reaching Florida , prompting marine biologists at the Florida Atlantic University Harbor Branch Oceanographic Institute to issue a warning against the presence of Vibrio bacteria on the algae. The bacteria stick to plastic debris that gets tangled in

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