| Rio Negro | |
| Name Other: | Guainía River |
| Map: | Negroamazonrivermap.png |
| Map Size: | 270 |
| Pushpin Map Size: | 270 |
| Subdivision Type1: | Countries |
| Length: | Rio Negro–Guainía [1] |
| Width Avg: | [2] |
| Depth Avg: | (Serrinha); to (Manaus)[3] |
| Depth Max: | (Manaus)[4] |
| Discharge1 Location: | Manaus |
| Discharge1 Min: | [5] |
| Discharge1 Avg: | (Period: 2015–2019)[6] |
| Discharge1 Max: | [7] |
| Discharge2 Location: | Paricatuba (Anavilhanas) |
| Discharge2 Min: | (2009/10) |
| Discharge2 Avg: | (Period: 2008–2019) |
| Discharge2 Max: | (2014/06)[8] |
| Discharge3 Location: | Serrinha, -0.4826°N -64.8268°W |
| Discharge3 Min: | [9] |
| Discharge3 Avg: | (Period: 1997–2015)[10] |
| Discharge3 Max: | [11] |
| Discharge4 Location: | São Felipe, 0.3699°N -67.3119°W |
| Discharge4 Min: | [12] |
| Discharge4 Avg: | (Period: 1997–2014)[13] |
| Discharge4 Max: | [14] |
| Discharge5 Min: | [15] |
| Discharge5 Avg: | (Period: 1997–2014)[16] |
| Discharge5 Max: | [17] |
| Source1: | highlands of Colombia |
| Source1 Location: | Guainía Department, Amazon region, Colombia |
| Source1 Coordinates: | 1.9472°N -70.0319°W (approximately) |
| Source1 Elevation: | (approximately) |
| Mouth: | Amazon River |
| Mouth Location: | Manaus, Amazonas State, Brazil |
| Mouth Coordinates: | -3.1333°N -59.9083°W |
| Mouth Elevation: | [18] |
| Progression: | Amazon → Atlantic Ocean |
| River System: | Amazon River |
| Basin Size: | [19] |
| Tributaries Left: | Casiquiare, Cauaburi, Marauiá, Macucuaú, Padauari, Demini, Jufari, Branco, Jauaperi, Camanaú, Baependi, Apuaú, Cuieiras, Tarumã Mirim, Tarumã Açu |
| Tributaries Right: | Guainía (Upper Negro), Xié, Içana, Uaupés, Curicuriari, Marié, Tea, Uneiuxi, Aiuanã, Urubaxi, Ararirá, Cuiuni, Caurés, Unini, Jaú, Puduari |
The Rio Negro (Portuguese: Rio Negro|br pronounced as /pt/; Spanish; Castilian: Río Negro| pronounced as /es/ "Black River"), or Guainía as it is known in its upper part, is the largest left tributary of the Amazon River (accounting for about 14% of the water in the Amazon basin), the largest blackwater river in the world,[20] and one of the world's ten largest rivers by average discharge. Despite its high flow, the Rio Negro has a low sediment load (5.76 million tonnes per year on average in Manaus).[21]
The source of the Rio Negro lies in Colombia, in the Department of Guainía where the river is known as the Guainía River.[22] The young river generally flows in an east-northeasterly direction through the Puinawai National Reserve, passing several small indigenous settlements on its way, such as Cuarinuma, Brujas, Santa Rosa and Tabaquén. After roughly the river starts forming the border between Colombia's Department of Guainía and Venezuela's Amazonas State. After passing the Colombian community of Tonina and Macanal the river turns southwest. Maroa is the first Venezuelan town the river passes. further downstream the river receives the Casiquiare canal from the left (north), forming a unique link between the Orinoco and the Amazon river basin. Henceforth the river is called Rio Negro.
The river now continues in a southeastern direction passing the Venezuelan town of San Carlos de Río Negro, its largest settlement on the river, and Colombia's San Felipe.In this stretch the river is constantly fed with tributaries from both sides, and it quickly grows in size creating large river islands, a common feature for all rivers in the Amazon basin. After forming the border between Colombia and Venezuela for the Rio Negro reaches the Piedra del Cocuy, an igneous rock formation from the Precambrian era, belonging to the Guyana Shield. Here the Tripoint of Colombia, Venezuela and Brazil is found in the middle of the river and it now completely enters Amazonas State, Brazil. After passing Cucuí, the river continues south, only temporarily turning west for several kilometers. In Missão Boa Vista the Içana River joins the Rio Negro and in São Joaquim the Uaupes River, the largest tributary of the Rio Negro, also enters from the right hand side. The Rio Negro now turns markedly towards the east, forming several rapids and small islets on its way. It then passes Sao Gabriel da Cachoeira an important commercial city. After several more rapids and imposing views of the Adormecida mountain chain the river leaves the Guyana shield it traversed in its upper and middle course.
After the Marié River enters the Rio Negro the river continues its eastward course forming many large islands and becoming very wide at several locations. It passes local communities such as Santa Isabel do Rio Negro. During the wet season, the river floods the country far and wide here, sometimes to a width of, for long distances. During this season, from April until October, it is a succession of lagoons, full of long islands and intricate channels with a lot of water wildlife. Near Carvoeiro the last major tributary of the Rio Negro, the Branco River joins the Rio Negro and the river temporarily forms the border between the state of Roraima and Amazonas State, Brazil. The river now takes a more southeastern course, becoming again very wide in many stretches before reaching the biggest city on its course Manaus.
The Anavilhanas National Park, a conservation unit that was originally an ecological station created in 1981, protects part of the Anavilhanas river archipelago in this part of the river.Below the archipelago, it meets the Solimões River to form the Amazon River, creating a phenomenon known as the Meeting of Waters.
List of the major tributaries of the Rio Negro (from the mouth upwards)[23] [24] [25] [26]
| Left tributary | Right tributary | Length | Basin size | Average discharge | - !km | mi !km2 | sq mi !m3/s | cu ft/s | |||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Rio Negro | 2362disp=tableNaNdisp=table | 719216disp=tableNaNdisp=table | 30640.8disp=tableNaNdisp=table | ||||||||
| Lower Rio Negro | |||||||||||
| Taruma-Açu | 139disp=tableNaNdisp=table | 1372disp=tableNaNdisp=table | 52.3disp=tableNaNdisp=table | ||||||||
| Cuieiras | when adding a value--> | 3441disp=tableNaNdisp=table | 144.2disp=tableNaNdisp=table | ||||||||
| Apuaú | when adding a value--> | 3799.1disp=tableNaNdisp=table | 153.6disp=tableNaNdisp=table | ||||||||
| Puduari | when adding a value--> | 3411.5disp=tableNaNdisp=table | 128.6disp=tableNaNdisp=table | ||||||||
| Camanaú | when adding a value--> | 11832.2disp=tableNaNdisp=table | 408disp=tableNaNdisp=table | ||||||||
| Jaú | 400disp=tableNaNdisp=table | 18896.6disp=tableNaNdisp=table | 869.2disp=tableNaNdisp=table | ||||||||
| Jauaperi | 554disp=tableNaNdisp=table | 39823.5disp=tableNaNdisp=table | 1336.8disp=tableNaNdisp=table | ||||||||
| Unini | 530disp=tableNaNdisp=table | 27433disp=tableNaNdisp=table | 1501.4disp=tableNaNdisp=table | ||||||||
| Branco | 1430disp=tableNaNdisp=table | 190789.2disp=tableNaNdisp=table | 5400disp=tableNaNdisp=table | ||||||||
| Jufari | 311disp=tableNaNdisp=table | 12590.5disp=tableNaNdisp=table | 446.6disp=tableNaNdisp=table | ||||||||
| Cauarés | when adding a value--> | 7332.3disp=tableNaNdisp=table | 296disp=tableNaNdisp=table | ||||||||
| Demini | when adding a value--> | 39769.6disp=tableNaNdisp=table | 1357.9disp=tableNaNdisp=table | ||||||||
| Cuiuni | 400disp=tableNaNdisp=table | 11776.1disp=tableNaNdisp=table | 491.6disp=tableNaNdisp=table | ||||||||
| Igarapé Adairá | when adding a value--> | 3294.9disp=tableNaNdisp=table | 101.1disp=tableNaNdisp=table | ||||||||
| Ararirá | when adding a value--> | 3425disp=tableNaNdisp=table | 114.6disp=tableNaNdisp=table | ||||||||
| Ererê | when adding a value--> | 3251disp=tableNaNdisp=table | 115.7disp=tableNaNdisp=table | ||||||||
| Padauari | when adding a value--> | 17384disp=tableNaNdisp=table | 606.8disp=tableNaNdisp=table | ||||||||
| Daraá | when adding a value--> | 3053.3disp=tableNaNdisp=table | 114.9disp=tableNaNdisp=table | ||||||||
| Urubaxi | 250disp=tableNaNdisp=table | 6855.9disp=tableNaNdisp=table | 311.6disp=tableNaNdisp=table | ||||||||
| Aiuanã | when adding a value--> | 4590.7disp=tableNaNdisp=table | 185.2disp=tableNaNdisp=table | ||||||||
| Uneiuxi | when adding a value--> | 12474.7disp=tableNaNdisp=table | 488.3disp=tableNaNdisp=table | ||||||||
| Teá | when adding a value--> | 6365.9disp=tableNaNdisp=table | 201.4disp=tableNaNdisp=table | ||||||||
| Marauiá | when adding a value--> | 6712disp=tableNaNdisp=table | 255.3disp=tableNaNdisp=table | ||||||||
| Igarapé Inambu | when adding a value--> | 4618.8disp=tableNaNdisp=table | 140.6disp=tableNaNdisp=table | ||||||||
| Cauaburi | when adding a value--> | 12139.3disp=tableNaNdisp=table | 442.9disp=tableNaNdisp=table | ||||||||
| Middle Rio Negro | |||||||||||
| Marié | 800disp=tableNaNdisp=table | 25378disp=tableNaNdisp=table | 1226.8disp=tableNaNdisp=table | ||||||||
| Curicuriari | when adding a value--> | 14202.2disp=tableNaNdisp=table | 916.8disp=tableNaNdisp=table | ||||||||
| Uaupés | 1375disp=tableNaNdisp=table | 64370.4disp=tableNaNdisp=table | 4344.9disp=tableNaNdisp=table | ||||||||
| Içana | 696disp=tableNaNdisp=table | 35675.3disp=tableNaNdisp=table | 2278.9disp=tableNaNdisp=table | ||||||||
| Xié | when adding a value--> | 8222disp=tableNaNdisp=table | 488.1disp=tableNaNdisp=table | ||||||||
| Upper Rio Negro | |||||||||||
| Casiquiare | 354disp=tableNaNdisp=table | 42478disp=tableNaNdisp=table | 2575.8disp=tableNaNdisp=table | ||||||||
| Guainía | 617disp=tableNaNdisp=table | 28899.5disp=tableNaNdisp=table | 2432.7disp=tableNaNdisp=table | ||||||||
Average discharge
| Period ! Discharge | Ref. | ||
|---|---|---|---|
| Encontro das Águas | |||
| 1979–2015 | [27] | ||
| 1971–2000 | [28] | ||
| Manaus-3.1387°N -60.0276°W | |||
| 2015–2019 | [29] | ||
| 1980–2006 | [30] | ||
| 1973–1992 | [31] | ||
| 1971–2000 | [32] | ||
| Paricatuba-3.0815°N -60.2335°W | |||
| 2008–2019 | |||
| 1971–2000 | [33] | ||
| Barcelos-0.9832°N -62.859°W | |||
| 1971–2000 | [34] | ||
| Serrinha-0.4826°N -64.8268°W | |||
| 1997–2015 | [35] | ||
| 1980–2006 | [36] | ||
| 1971–2000 | [37] | ||
| São Gabriel da Cachoeira-0.1342°N -67.094°W | |||
| 1971–2000 | [38] | ||
| São Felipe0.3699°N -67.3119°W | |||
| 1997–2014 | [39] | ||
| 1980–2006 | [40] | ||
| 1971–2000 | [41] | ||
| Cucuí-1.188°N -66.8399°W | |||
| 1997–2014 | [42] | ||
| 1980–2006 | [43] | ||
| 1971–2000 | [44] | ||
The river was named by the Spanish explorer Francisco de Orellana, who first came upon it in 1541. By the middle of the 17th century, Jesuits had settled along its banks in the midst of numerous tribes: Manau, Aruák, and Trumá Indians. After 1700 slaving along the river was common, and Native American populations were greatly diminished after contact with Eurasian diseases.[22] This area was the filming location for Survivor:The Amazon in 2003.
While the name Rio Negro means Black River, its waters are similar in colour to strong tea, which is typical of blackwater rivers. The dark color comes from humic acid due to an incomplete breakdown of phenol-containing vegetation from sandy clearings. The river was named because it looks black from a distance.
Much has been written on the productivity of the Rio Negro and other blackwater rivers. The older idea that these are "hunger rivers" is giving way, with new research, to the recognition that the Rio Negro, for example, supports a large fishing industry and has numerous turtle beaches. If explorers did not find many Indigenous peoples along the Rio Negro during the 17th century, it is likely that their populations were reduced because of new infectious diseases and warfare rather than low river productivity.
Rio Negro has a very high species richness. About 700 fish species have been documented in the river basin, and it is estimated that the total is 800–900 fish species, including almost 100 endemics and several undescribed species.[45] Among these are many that are important in the aquarium trade, including the cardinal tetra.[45] As a result of the Casiquiare canal, many aquatic species are found both in the Rio Negro and Orinoco. Because the Casiquiare includes both blackwater and clear- to whitewater sections, only relatively adaptable species are able to pass through it between the two river systems.[46]
The sixth season of Survivor, was filmed in Rio Negro in 2003.