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83-780: The river is 786 kilometres (488 mi) long. The area of its basin is 27,300 square kilometres (10,500 sq mi). The Rassokha is formed by the confluence of the rivers Ilin-Yuryakh and Arga-Yuryakh in the Kolyma Lowland . The original sources of the uppermost river in the network are in the Ulakhan-Sis Range . The Rassokha flows across the Middle Kolyma District and the Lower Kolyma District in an area marked by permafrost , with numerous swamps and lakes. Finally it joins

166-427: A hierarchical pattern . Other terms for a drainage basin are catchment area , catchment basin , drainage area , river basin , water basin , and impluvium . In North America, they are commonly called a watershed , though in other English-speaking places, "watershed" is used only in its original sense, that of the drainage divide line. A drainage basin's boundaries are determined by watershed delineation ,

249-437: A common task in environmental engineering and science. In a closed drainage basin, or endorheic basin , rather than flowing to the ocean, water converges toward the interior of the basin, known as a sink , which may be a permanent lake, a dry lake , or a point where surface water is lost underground . Drainage basins are similar but not identical to hydrologic units , which are drainage areas delineated so as to nest into

332-454: A drainage basin, and there are different ways to interpret that data. In the unlikely event that the gauges are many and evenly distributed over an area of uniform precipitation, using the arithmetic mean method will give good results. In the Thiessen polygon method, the drainage basin is divided into polygons with the rain gauge in the middle of each polygon assumed to be representative for

415-540: A drainage boundary is referred to as watershed delineation . Finding the area and extent of a drainage basin is an important step in many areas of science and engineering. Most of the water that discharges from the basin outlet originated as precipitation falling on the basin. A portion of the water that enters the groundwater system beneath the drainage basin may flow towards the outlet of another drainage basin because groundwater flow directions do not always match those of their overlying drainage network. Measurement of

498-698: A fleet to reach Peru by sea, and sought the military support of various rebels from the Viceroyalty of Peru. In 1822 the two men met at the Guayaquil Conference in Ecuador, where they failed to agree on governance strategies for the liberated nations. Two years later Bolívar's forces beat the Spanish at the Battle of Ayacucho , securing the independence of Peru and the rest of South America. In

581-459: A long history of colonialism , the overwhelming majority of South Americans speak Spanish or Portuguese , and societies and states are rich in Western traditions . Relative to Africa, Asia, and Europe, post-1900 South America has been a peaceful continent with few wars, although high rates of violent crime remain a concern in some countries. South America occupies the southern portion of

664-602: A multi-level hierarchical drainage system . Hydrologic units are defined to allow multiple inlets, outlets, or sinks. In a strict sense, all drainage basins are hydrologic units but not all hydrologic units are drainage basins. About 48.71% of the world's land drains to the Atlantic Ocean . In North America , surface water drains to the Atlantic via the Saint Lawrence River and Great Lakes basins,

747-682: A part of Oceania, also administered by Chile), the Galápagos Islands (administered by Ecuador , sometimes considered part of Oceania), and Tierra del Fuego (split between Argentina and Chile). In the Atlantic Ocean, Brazil administers Fernando de Noronha , Trindade and Martim Vaz , and the Saint Peter and Saint Paul Archipelago , while the Falkland Islands (Spanish: Islas Malvinas ) and South Georgia and

830-481: A site called Chavín de Huantar in modern Peru at an elevation of 3,177 meters (10,423 ft). Chavín civilization spanned 900 BC to 300 BC. In the central coast of Peru, around the beginning of the 1st millennium AD, Moche (100 BC – 700 AD, at the northern coast of Peru), Paracas and Nazca (400 BC – 800 AD, Peru) cultures flourished with centralized states with permanent militia improving agriculture through irrigation and new styles of ceramic art. At

913-689: A subtropical climate of the dinaric type. At the highest points of the Andean region, climates are colder than the ones occurring at the highest point of the Norwegian fjords. In the Andean plateaus, the warm climate prevails, although it is tempered by the altitude, while in the coastal strip, there is an equatorial climate of the Guinean type. From this point until the north of the Chilean coast appear, successively, Mediterranean oceanic climate , temperate of

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996-418: Is an area of land in which all flowing surface water converges to a single point, such as a river mouth , or flows into another body of water , such as a lake or ocean . A basin is separated from adjacent basins by a perimeter, the drainage divide , made up of a succession of elevated features, such as ridges and hills . A basin may consist of smaller basins that merge at river confluences , forming

1079-526: Is because the most extensive part of the continent is in the equatorial zone (the region has more areas of equatorial plains than any other region), therefore giving the Southern Cone more oceanic influence, which moderates year round temperatures. The average annual temperatures in the Amazon basin oscillate around 27 °C (81 °F), with low thermal amplitudes and high rainfall indices. Between

1162-460: Is by far the most populous South American country, with almost half of the continent's population, followed by Colombia, Argentina, Venezuela, and Peru. In recent decades, Brazil has also generated half of the continent's GDP and has become the continent's first regional power. Most of the population lives near the continent's western or eastern coasts while the interior and the far south are sparsely populated. The geography of western South America

1245-605: Is dominated by the Andes mountains; in contrast, the eastern part contains both highland regions and vast lowlands where rivers such as the Amazon , Orinoco and Paraná flow. Most of the continent lies in the tropics, except for a large part of the Southern Cone located in the middle latitudes . The continent's cultural and ethnic outlook has its origin with the interaction of Indigenous peoples with European conquerors and immigrants and, more locally, with African slaves . Given

1328-614: Is now Colombia. They established the Muisca Confederation of many clans, or cacicazgos , that had a free trade network among themselves. Many were goldsmiths and farmers. Other important Pre-Columbian cultures include: the Cañaris (in south central Ecuador), Chimú Empire (1300–1470, Peruvian northern coast), Chachapoyas , and the Aymaran kingdoms (1000–1450, Western Bolivia and southern Peru). Holding their capital at

1411-480: Is one of the most biodiverse continents on Earth. It is home to many unique species of animals including the llama , anaconda , piranha , jaguar , vicuña , and tapir , and to one of the largest known insects in the world, the Titan beetle . The Amazon rainforests possess high biodiversity , with Brazil estimated to contain 10% of Earth's species . 83% of South America's large mammals ( megafauna ) became extinct at

1494-487: Is referred to as " watershed management ". In Brazil , the National Policy of Water Resources, regulated by Act n° 9.433 of 1997, establishes the drainage basin as the territorial division of Brazilian water management. When a river basin crosses at least one political border, either a border within a nation or an international boundary, it is identified as a transboundary river . Management of such basins becomes

1577-614: Is the Dead Sea . Drainage basins have been historically important for determining territorial boundaries, particularly in regions where trade by water has been important. For example, the English crown gave the Hudson's Bay Company a monopoly on the fur trade in the entire Hudson Bay basin, an area called Rupert's Land . Bioregional political organization today includes agreements of states (e.g., international treaties and, within

1660-582: Is the largest country in South America, covering a little less than half of the continent's land area and encompassing around half of the continent's population. The remaining countries and territories are divided among four subregions : the Andean states , Caribbean South America , The Guianas , and the Southern Cone . Physiographically, South America also includes some of the nearby islands. The Dutch ABC islands ( Aruba , Bonaire , and Curaçao ),

1743-662: The African Great Lakes , the interiors of Australia and the Arabian Peninsula , and parts in Mexico and the Andes . Some of these, such as the Great Basin, are not single drainage basins but collections of separate, adjacent closed basins. In endorheic bodies of water where evaporation is the primary means of water loss, the water is typically more saline than the oceans. An extreme example of this

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1826-519: The Altiplano , Tiahuanaco or Tiwanaku (100 BC – 1200 AD, Bolivia) managed a large commercial network based on religion. Around the 7th century, both Tiahuanaco and Wari or Huari Empire (600–1200, Central and northern Peru) expanded its influence to all the Andean region, imposing the Huari urbanism and Tiahuanaco religious iconography. The Muisca were the main indigenous civilization in what

1909-586: The Archipelago of San Andrés, Providencia and Santa Catalina ( San Andrés Island , Providencia Island , and Santa Catalina Island etc., which are administered by Colombia ) are politically parts of South American countries but physiographically parts of North America. Other islands often associated with geopolitical South America are the Chiloé Archipelago and Robinson Crusoe Island (both administered by Chile), Easter Island (culturally

1992-820: The Atacama Desert ; the wettest place on earth, López de Micay in Colombia; the largest rainforest, the Amazon rainforest ; the highest capital city, La Paz , Bolivia ; the highest commercially navigable lake in the world, Lake Titicaca ; and, excluding research stations in Antarctica , the world's southernmost permanently inhabited community, Puerto Toro , Chile. South America's major mineral resources are gold, silver, copper, iron ore, tin , and petroleum. These resources have brought high income to its countries, especially in times of war or of rapid economic growth by industrialized countries elsewhere. However,

2075-717: The Bering Land Bridge (now the Bering Strait ) at least 15,000 years ago from the territory that is present-day Russia. They migrated south through North America, and eventually reached South America through the Isthmus of Panama . Amongst the oldest evidence for human presence in South America is the Monte Verde II site in Chile, suggested to date to around 14,500 years ago. From around 13,000 years ago,

2158-634: The Caribbean colonies and Brazil, as European nations built up economically slave-dependent colonies in the New World . Nearly 40% of all African slaves trafficked to the Americas went to Brazil. An estimated 4.9 million slaves from Africa came to Brazil during the period from 1501 to 1866. In contrast to other European colonies in the Americas which mainly used the labor of African slaves, Spanish colonists mainly enslaved indigenous Americans. In 1750,

2241-607: The Eastern Seaboard of the United States, the Canadian Maritimes , and most of Newfoundland and Labrador . Nearly all of South America east of the Andes also drains to the Atlantic, as does most of Western and Central Europe and the greatest portion of western Sub-Saharan Africa , as well as Western Sahara and part of Morocco . The two major mediterranean seas of the world also flow to

2324-1030: The Falkland Islands and South Georgia and the South Sandwich Islands ; and one internal territory : French Guiana . The ABC islands of the Dutch Caribbean (north of Venezuela in the Leeward Antilles ), Ascension Island (a part of Saint Helena, Ascension and Tristan da Cunha ), Bouvet Island (a dependency of Norway ), Panama , and the Caribbean island country of Trinidad and Tobago may also be considered parts of South America. South America has an area of 17,840,000 square kilometers (6,890,000 sq mi). Its population as of 2021 has been estimated at more than 434 million. South America ranks fourth in area (after Asia, Africa, and North America) and fifth in population (after Asia, Africa, Europe, and North America). Brazil

2407-470: The Fishtail projectile point style became widespread across South America, with its disappearance around 11,000 years ago coincident with the disappearance of South America's megafauna. Maize was present in northern South America by around 6,000 years ago. By 2000 BC, many agrarian communities had been settled throughout the Andes and the surrounding regions. Fishing became a widespread practice along

2490-472: The Fortaleza area, contemporaneous with the pyramids of Ancient Egypt , one of the oldest-known civilizations in the Americas and one of the six sites where civilization separately originated in the ancient world. Caral–Supe governing class established a trade network and developed agriculture then followed by Chavín by 900 BC, according to some estimates and archaeological finds. Artifacts were found at

2573-706: The Kondakov Plateau and the Suor Uyata and the Ulakhan-Tas, is part of the migration corridor of the Sundrun reindeer population. This Sakha Republic location article is a stub . You can help Misplaced Pages by expanding it . This article related to a river in the Russian Far East is a stub . You can help Misplaced Pages by expanding it . Drainage basin A drainage basin

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2656-715: The Maracaibo Lake and the mouth of the Orinoco, predominates an equatorial climate of the type Congolese, that also includes parts of the Brazilian territory. The east-central Brazilian plateau has a humid and warm tropical climate. The northern and eastern parts of the Argentine pampas have a humid subtropical climate with dry winters and humid summers of the Chinese type, while the western and eastern ranges have

2739-682: The Mississippi (3.22 million km ), and the Río de la Plata (3.17 million km ). The three rivers that drain the most water, from most to least, are the Amazon, Ganges , and Congo rivers. Endorheic basin are inland basins that do not drain to an ocean. Endorheic basins cover around 18% of the Earth's land. Some endorheic basins drain to an Endorheic lake or Inland sea . Many of these lakes are ephemeral or vary dramatically in size depending on climate and inflow. If water evaporates or infiltrates into

2822-809: The Nile River ), Southern , Central, and Eastern Europe , Turkey , and the coastal areas of Israel , Lebanon , and Syria . The Arctic Ocean drains most of Western Canada and Northern Canada east of the Continental Divide , northern Alaska and parts of North Dakota , South Dakota , Minnesota , and Montana in the United States, the north shore of the Scandinavian peninsula in Europe, central and northern Russia, and parts of Kazakhstan and Mongolia in Asia , which totals to about 17% of

2905-599: The Orinoco Llanos and in the Guianas Plateau , the precipitation levels go from moderate to high. The Pacific coast of Colombia and northern Ecuador are rainy regions, with Chocó in Colombia being the rainiest place in the world along with the northern slopes of Indian Himalayas. The Atacama Desert, along this stretch of coast, is one of the driest regions in the world. The central and southern parts of Chile are subject to extratropical cyclones , and most of

2988-547: The Portuguese Crown abolished the enslavement of indigenous peoples in colonial Brazil , under the belief that they were unfit for labor and less effective than enslaved Africans. Enslaved Africans were brought to the Americas on slave ships , under inhuman conditions and ill-treatment, and those who survived were sold in slave markets . After independence, all South American countries maintained slavery for some time. The first South American country to abolish slavery

3071-738: The Portuguese Kingdom of Brazil , Dom Pedro I (also Pedro IV of Portugal), son of the Portuguese King Dom João VI , proclaimed the independent Kingdom of Brazil in 1822, which later became the Empire of Brazil . Despite the Portuguese loyalties of garrisons in Bahia , Cisplatina and Pará , independence was diplomatically accepted by Portugal in 1825, on condition of a high compensation paid by Brazil mediated by

3154-665: The South American Plate . South America is home to several superlatives, including the world's highest uninterrupted waterfall , Angel Falls in Venezuela; the highest single-drop waterfall Kaieteur Falls in Guyana; the largest river by volume, the Amazon River ; the longest mountain range, the Andes (whose highest mountain is Aconcagua at 6,962 m or 22,841 ft); the driest non-polar place on earth,

3237-613: The Spanish American wars of independence between the patriots, who promoted such autonomy, and the royalists , who supported Spanish authority over the Americas. The Juntas, in both Spain and the Americas, promoted the ideas of the Enlightenment . Five years after the beginning of the war, Ferdinand VII returned to the throne and began the Absolutist Restoration , as the royalists got the upper hand in

3320-641: The groundwater . A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere , with a considerably smaller portion in the Northern Hemisphere . It can also be described as

3403-712: The native populations had no immune resistance – caused large-scale depopulation of the native population under Spanish control. Systems of forced labor, such as the haciendas and mining industry's mit'a also contributed to the depopulation. After this, enslaved Africans , who had developed immunities to these diseases, were quickly brought in to replace them. The Spaniards were committed to converting their native subjects to Christianity and were quick to purge any native cultural practices that hindered this end; however, many initial attempts at this were only partially successful, as native groups simply blended Catholicism with their established beliefs and practices. Furthermore,

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3486-462: The Americas. The continent is generally delimited on the northwest by the Darién watershed along the Colombia–Panama border , although some may consider the border instead to be the Panama Canal . Geopolitically and geographically, all of Panama – including the segment east of the Panama Canal in the isthmus – is typically included in North America alone and among the countries of Central America . Almost all of mainland South America sits on

3569-418: The Andes. The Indian Ocean 's drainage basin also comprises about 13% of Earth's land. It drains the eastern coast of Africa, the coasts of the Red Sea and the Persian Gulf , the Indian subcontinent , Burma, and most parts of Australia . The five largest river basins (by area), from largest to smallest, are those of the Amazon (7 million km ), the Congo (4 million km ), the Nile (3.4 million km ),

3652-446: The Argentine Patagonia is desert . In the Pampas of Argentina, Uruguay and South of Brazil the rainfall is moderate, with rains well distributed during the year. The moderately dry conditions of the Chaco oppose the intense rainfall of the eastern region of Paraguay. In the semiarid coast of the Brazilian Northeast the rains are linked to a monsoon regime. Important factors in the determination of climates are sea currents, such as

3735-447: The Atlantic. The Caribbean Sea and Gulf of Mexico basin includes most of the U.S. interior between the Appalachian and Rocky Mountains , a small part of the Canadian provinces of Alberta and Saskatchewan , eastern Central America , the islands of the Caribbean and the Gulf, and a small part of northern South America. The Mediterranean Sea basin, with the Black Sea , includes much of North Africa , east-central Africa (through

3818-479: The Breton type and, already in Tierra del Fuego , cold climate of the Siberian type. The distribution of rainfall is related to the regime of winds and air masses. In most of the tropical region east of the Andes, winds blowing from the northeast, east and southeast carry moisture from the Atlantic, causing abundant rainfall. However, due to a consistently strong wind shear and a weak Intertropical Convergence Zone , South Atlantic tropical cyclones are rare. In

3901-447: The South Sandwich Islands ( biogeographically and hydrologically associated with Antarctica) have been administered as two British Overseas Territories under the Crown , whose sovereignty over the islands is disputed by Argentina . An isolated volcanic island on the South American Plate , Ascension Island is geologically a part of South America. Administered as a dependency of Saint Helena, Ascension and Tristan da Cunha ,

3984-830: The Spaniards brought their language to the degree they did with their religion, although the Roman Catholic Church 's evangelization in Quechua , Aymara , and Guaraní actually contributed to the continuous use of these native languages albeit only in the oral form. Eventually, the natives and the Spaniards interbred, forming a mestizo class. At the beginning, many mestizos of the Andean region were offspring of Amerindian mothers and Spanish fathers. After independence, most mestizos had native fathers and European or mestizo mothers. Many native artworks were considered pagan idols and destroyed by Spanish explorers; this included many gold and silver sculptures and other artifacts found in South America, which were melted down before their transport to Spain or Portugal. Spaniards and Portuguese brought

4067-483: The Spanish and Portuguese colonies. First, Napoleon invaded Portugal, but the House of Braganza avoided capture by escaping to Brazil . Napoleon captured King Ferdinand VII of Spain, and appointed his own brother instead. This appointment provoked popular resistance, which created Juntas to rule in the name of the captured king. Many cities in the Spanish colonies, however, considered themselves equally authorized to appoint local Juntas like those of Spain. This began

4150-417: The US, interstate compacts ) or other political entities in a particular drainage basin to manage the body or bodies of water into which it drains. Examples of such interstate compacts are the Great Lakes Commission and the Tahoe Regional Planning Agency . In hydrology , the drainage basin is a logical unit of focus for studying the movement of water within the hydrological cycle . The process of finding

4233-423: The United Kingdom. The newly independent nations began a process of fragmentation, with several civil and international wars. However, it was not as strong as in Central America. Some countries created from provinces of larger countries stayed as such up to modern times (such as Paraguay or Uruguay), while others were reconquered and reincorporated into their former countries (such as the Republic of Entre Ríos and

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4316-406: The basin, it can form tributaries that change the structure of the land. There are three different main types, which are affected by the rocks and ground underneath. Rock that is quick to erode forms dendritic patterns, and these are seen most often. The two other types of patterns that form are trellis patterns and rectangular patterns. Rain gauge data is used to measure total precipitation over

4399-437: The coast, helping establish fish as a primary source of food. Irrigation systems were also developed at this time, which aided in the rise of an agrarian society . South American cultures began domesticating llamas , vicuñas , guanacos , and alpacas in the highlands of the Andes circa 3500 BC. Besides their use as sources of meat and wool, these animals were used for transportation of goods. The rise of plant growing and

4482-461: The concentration in producing one, or few, major export commodities has often hindered the development and diversification of its economies. The fluctuation in the price of commodities in international markets has led historically to major highs and lows, booms and busts, in the economies of South American states, often causing political instability. This has led for calls to diversify production and increase trade within South America itself. Brazil

4565-424: The conflict. The independence of South America was secured by Simón Bolívar (Venezuela) and José de San Martín (Argentina), the two most important Libertadores . Bolívar led a great uprising in the north, then led his army south towards Lima , the capital of the Viceroyalty of Peru . Meanwhile, San Martín led an army across the Andes Mountains, along with Chilean expatriates, and liberated Chile. He organized

4648-405: The current Humboldt and Falklands . The equatorial current of the South Atlantic strikes the coast of the Northeast and there is divided into two others: the current of Brazil and a coastal current that flows to the northwest towards the Antilles , where there it moves towards northeast course thus forming the most Important and famous ocean current in the world, the Gulf Stream . South America

4731-430: The discharge of water from a basin may be made by a stream gauge located at the basin's outlet. Depending on the conditions of the drainage basin, as rainfall occurs some of it seeps directly into the ground. This water will either remain underground, slowly making its way downhill and eventually reaching the basin, or it will permeate deeper into the soil and consolidate into groundwater aquifers. As water flows through

4814-441: The drainage area is dependent on the soil type. Certain soil types such as sandy soils are very free-draining, and rainfall on sandy soil is likely to be absorbed by the ground. However, soils containing clay can be almost impermeable and therefore rainfall on clay soils will run off and contribute to flood volumes. After prolonged rainfall even free-draining soils can become saturated , meaning that any further rainfall will reach

4897-642: The drainage basin to the mouth, and may accumulate there, disturbing the natural mineral balance. This can cause eutrophication where plant growth is accelerated by the additional material. Because drainage basins are coherent entities in a hydrological sense, it has become common to manage water resources on the basis of individual basins. In the U.S. state of Minnesota , governmental entities that perform this function are called " watershed districts ". In New Zealand, they are called catchment boards. Comparable community groups based in Ontario, Canada, are called conservation authorities . In North America, this function

4980-427: The end of the Pleistocene around 11,000 years ago as part of the Quaternary extinction event , among the highest of any continent, with the casualties including saber-toothed cats , ground sloths , glyptodonts , gomphotheres , the equines Hippidion and Equus neogeus , and all remaining South American native ungulates . South America is thought to have been first inhabited by humans when people were crossing

5063-502: The great city of Cusco , the Inca civilization dominated the Andes region from 1438 to 1533. Known as Tawantin suyu , and "the land of the four regions", in Quechua , the Inca Empire was highly distinct and developed. Inca rule extended to nearly a hundred linguistic or ethnic communities, some nine to fourteen million people connected by a 25,000 kilometer road system . Cities were built with precise, unmatched stonework, constructed over many levels of mountain terrain. Terrace farming

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5146-435: The ground and along rivers it can pick up nutrients , sediment , and pollutants . With the water, they are transported towards the outlet of the basin, and can affect the ecological processes along the way as well as in the receiving water body . Modern use of artificial fertilizers , containing nitrogen (as nitrates ), phosphorus , and potassium , has affected the mouths of drainage basins. The minerals are carried by

5229-422: The ground at its terminus, the area can go by several names, such playa, salt flat, dry lake , or alkali sink . The largest endorheic basins are in Central Asia , including the Caspian Sea , the Aral Sea , and numerous smaller lakes. Other endorheic regions include the Great Basin in the United States, much of the Sahara Desert , the drainage basin of the Okavango River ( Kalahari Basin ), highlands near

5312-417: The island is geopolitically a part of Africa. All of the world's major climate zones are present in South America. The distribution of the average temperatures in the region presents a constant regularity from the 30° of latitude south , when the isotherms tend, more and more, to be confused with the degrees of latitude. In temperate latitudes, winters and summers are milder than in North America. This

5395-487: The islands of Trinidad and Tobago ( Trinidad Island and Tobago Island etc.), the State of Nueva Esparta , and the Federal Dependencies of Venezuela sit on the northern portion of the South American continental shelf and are sometimes considered parts of the continent. Geopolitically, all the island countries and territories in the Caribbean have generally been grouped as a subregion of North America instead. By contrast, Aves Island (administered by Venezuela ) and

5478-466: The land outside Europe should be an exclusive duopoly between the two countries. The treaty established an imaginary line along a north–south meridian 370 leagues west of the Cape Verde Islands , roughly 46° 37' W. In terms of the treaty, all land to the west of the line (known to comprise most of the South American soil) would belong to Spain, and all land to the east, to Portugal. As accurate measurements of longitude were impossible at that time,

5561-410: The left bank of the Alazeya 383 km (238 mi) from its mouth. The Rassokha has 145 tributaries that are longer than 10 km (6.2 mi) and in its basin there are 7,442 lakes with a total area of 3,240 km (1,250 sq mi). The river freezes in late September through early October and stays icebound until the end of May. The forest tundra of the Rassokha basin, together with

5644-476: The line was not strictly enforced, resulting in a Portuguese expansion of Brazil across the meridian. Beginning in the 1530s, the people and natural resources of South America were repeatedly exploited by foreign conquistadors , first from Spain and later from Portugal. These competing colonial nations claimed the land and resources as their own and divided it into colonies. European infectious diseases ( smallpox , influenza , measles , and typhus ) – to which

5727-402: The mid-17th century. It became a Dutch colony in 1667. The indigenous peoples of the Americas in various European colonies were forced to work in European plantations and mines; along with enslaved Africans who were also introduced in the proceeding centuries via the slave trade . European colonists were heavily dependent on indigenous labor during the initial phases of settlement to maintain

5810-418: The rainfall on the area of land included in its polygon. These polygons are made by drawing lines between gauges, then making perpendicular bisectors of those lines form the polygons. The isohyetal method involves contours of equal precipitation are drawn over the gauges on a map. Calculating the area between these curves and adding up the volume of water is time-consuming. Isochrone maps can be used to show

5893-572: The responsibility of the countries sharing it. Nile Basin Initiative , OMVS for Senegal River , Mekong River Commission are a few examples of arrangements involving management of shared river basins. Management of shared drainage basins is also seen as a way to build lasting peaceful relationships among countries. The catchment is the most significant factor determining the amount or likelihood of flooding . Catchment factors are: topography , shape, size, soil type, and land use (paved or roofed areas). Catchment topography and shape determine

5976-461: The river rather than being absorbed by the ground. If the surface is impermeable the precipitation will create surface run-off which will lead to higher risk of flooding; if the ground is permeable, the precipitation will infiltrate the soil. Land use can contribute to the volume of water reaching the river, in a similar way to clay soils. For example, rainfall on roofs, pavements , and roads will be collected by rivers with almost no absorption into

6059-615: The southern subregion of the Americas . South America is bordered on the west by the Pacific Ocean and on the north and east by the Atlantic Ocean ; North America and the Caribbean Sea lie to the northwest. The continent includes twelve sovereign states : Argentina , Bolivia , Brazil , Chile , Colombia , Ecuador , Guyana , Paraguay , Peru , Suriname , Uruguay , and Venezuela ; two dependent territories :

6142-418: The speed with which the runoff reaches a river. A long thin catchment will take longer to drain than a circular catchment. Size will help determine the amount of water reaching the river, as the larger the catchment the greater the potential for flooding. It is also determined on the basis of length and width of the drainage basin. Soil type will help determine how much water reaches the river. The runoff from

6225-421: The subsequent appearance of permanent human settlements allowed for the multiple and overlapping beginnings of civilizations in South America. One of the earliest known South American civilizations was Caral–Supe , on the central Peruvian coast. Though a pre-ceramic culture, the monumental architecture of Caral–Supe created one of the first cities of the world, generally dated to around 3500 BC, at Huaricanga in

6308-411: The subsistence economy, and natives were often captured by expeditions. The importation of African slaves began midway through the 16th century, but the enslavement of indigenous peoples continued well into the 17th and 18th centuries. The Atlantic slave trade brought enslaved Africans primarily to South American colonies, beginning with the Portuguese since 1502. The main destinations of this phase were

6391-415: The time taken for rain to reach the river, while catchment size, soil type, and development determine the amount of water to reach the river. Generally, topography plays a big part in how fast runoff will reach a river. Rain that falls in steep mountainous areas will reach the primary river in the drainage basin faster than flat or lightly sloping areas (e.g., > 1% gradient). Shape will contribute to

6474-477: The time taken for runoff water within a drainage basin to reach a lake, reservoir or outlet, assuming constant and uniform effective rainfall. Drainage basins are the principal hydrologic unit considered in fluvial geomorphology . A drainage basin is the source for water and sediment that moves from higher elevation through the river system to lower elevations as they reshape the channel forms. Drainage basins are important in ecology . As water flows over

6557-573: The western European architectural style to the continent, and helped to improve infrastructures like bridges, roads, and the sewer system of the cities they discovered or conquered. They also significantly increased economic and trade relations, not just between the old and new world but between the different South American regions and peoples. Finally, with the expansion of the Portuguese and Spanish languages, many cultures that were previously separated became united through that of Latin American. Guyana

6640-727: The world's land. Just over 13% of the land in the world drains to the Pacific Ocean . Its basin includes much of China, eastern and southeastern Russia, Japan, the Korean Peninsula , most of Indochina, Indonesia and Malaysia, the Philippines, all of the Pacific Islands , the northeast coast of Australia , and Canada and the United States west of the Continental Divide (including most of Alaska), as well as western Central America and South America west of

6723-472: Was Chile in 1823, Uruguay in 1830, Bolivia in 1831, Guyana in 1833, Colombia and Ecuador in 1851, Argentina in 1853, Peru and Venezuela in 1854, Suriname in 1863, Paraguay in 1869, and in 1888 Brazil was the last South American nation and the last country in western world to abolish slavery. The European Peninsular War (1807–14), a theater of the Napoleonic Wars , changed the political situation of

6806-689: Was a useful form of agriculture. The Mapuche in Central and Southern Chile resisted the European and Chilean settlers, waging the Arauco War for more than 300 years. In 1494, Portugal and Spain, the two great maritime European powers of that time, on the expectation of new lands being discovered in the west, signed the Treaty of Tordesillas , by which they agreed, with the support of the Pope, that all

6889-562: Was initially colonized by the Dutch before coming under British control , though there was a brief period during the Napoleonic Wars when it was occupied by the French . The region was initially partitioned between the Dutch, French and British before fully coming under the control of Britain. Suriname was first explored by the Spanish in the 16th century and then settled by the English in

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