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96-636: Coxilha is a municipality in the state of Rio Grande do Sul , Brazil . As of 2020, the estimated population was 2,743. 28°07′37″S 52°17′45″W  /  28.12694°S 52.29583°W  / -28.12694; -52.29583 This geographical article relating to Rio Grande do Sul is a stub . You can help Misplaced Pages by expanding it . Rio Grande do Sul Rio Grande do Sul ( UK : / ˌ r iː uː ˌ ɡ r æ n d i d uː ˈ s ʊ l / , US : /- ˌ ɡ r ɑː n d i d uː ˈ s uː l / , Portuguese: [ˈʁi.u ˈɡɾɐ̃dʒ(i) du ˈsuw] ; lit. "Great River of

192-571: A gaucho culture with its neighbors Argentina and Uruguay. Before the arrival of Portuguese and Spanish settlers, it was inhabited mostly by the Guarani and Kaingang peoples (with smaller populations of Charrúa and Minuane ). The first Europeans there were Jesuits , followed by settlers from the Azores . In the 19th century it was the scene of conflicts including the Ragamuffin War and

288-535: A Province of Brazil (Província Cisplatina). This situation outlasted Brazil's independence from Portugal in 1822; in 1825, however, Juan Antonio Lavalleja proclaimed the independence of Uruguay; war followed, until in 1828 Brazil recognized Uruguayan independence. Populating Rio Grande do Sul was a constant concern of the Portuguese. To that end, the metropolitan Crown distributed land in the form of enormous latifundia . In those large latifundia, cattle raising

384-522: A genetic study from 2013, Brazilians in Rio Grande do Sul have an average of 73% European, 14% African and 13% Amerindian ancestry. Ethnicities of Rio Grande do Sul in 2022 People of Portuguese – mostly Azorean – background predominate in the coastal region. The Southwest, on the other hand, was originally populated by Pampeano Indians. Like the other Gauchos from the La Plata Basin

480-573: A harsh environment for organisms. Sediment often settles in intertidal mudflats which are extremely difficult to colonize. No points of attachment exist for algae , so vegetation based habitat is not established. Sediment can also clog feeding and respiratory structures of species, and special adaptations exist within mudflat species to cope with this problem. Lastly, dissolved oxygen variation can cause problems for life forms. Nutrient-rich sediment from human-made sources can promote primary production life cycles, perhaps leading to eventual decay removing

576-595: A hero in his native Italy). The Empire soon retook initiative, though, and from them on the rebels fought in the defensive. In 1842, the Empire assigned a new Provincial governor and military commander, the Baron, later Duke of Caxias . The inability of the rebels to secure contact with the world through a seaport, the dwindling economy of the Province, combined with Caxias' superior capabilities as military commander, led to

672-529: A number of coastal water bodies such as coastal lagoons and brackish seas. A more comprehensive definition of an estuary is "a semi-enclosed body of water connected to the sea as far as the tidal limit or the salt intrusion limit and receiving freshwater runoff; however the freshwater inflow may not be perennial, the connection to the sea may be closed for part of the year and tidal influence may be negligible". This broad definition also includes fjords , lagoons , river mouths , and tidal creeks . An estuary

768-589: A secondary front. But in 1865 a Paraguayan division invaded the state, occupying Uruguaiana by August 5. By August 16, troops of the Triple Alliance put siege to Uruguaiana, and by September 17, an ultimatum was delivered to General Estigarribia, commander of the Paraguayan division. Having no possibility of breaking the siege or defending the position, the Paraguayans surrendered, under conditions,

864-548: A similar position farther south, on the Uruguayan border, and is about 175 kilometres (109 mi) long by 10 to 35 km wide. It is more irregular in outline and discharges into Lagoa dos Patos through a navigable channel known as the São Gonçalo Channel . A part of the lake lies in Uruguayan territory, but its navigation, as determined by treaty, belongs exclusively to Brazil. Both of these lakes are evidently

960-408: A type of ecosystem in some estuaries that have been negatively impacted by eutrophication. Cordgrass vegetation dominates the salt marsh landscape. Excess nutrients allow the plants to grow at greater rates in above ground biomass, however less energy is allocated to the roots since nutrients is abundant. This leads to a lower biomass in the vegetation below ground which destabilizes the banks of

1056-407: A variety of factors including soil erosion , deforestation , overgrazing , overfishing and the filling of wetlands. Eutrophication may lead to excessive nutrients from sewage and animal wastes; pollutants including heavy metals , polychlorinated biphenyls , radionuclides and hydrocarbons from sewage inputs; and diking or damming for flood control or water diversion. The word "estuary"

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1152-563: A well-mixed water column and the disappearance of the vertical salinity gradient . The freshwater-seawater boundary is eliminated due to the intense turbulent mixing and eddy effects . The lower reaches of Delaware Bay and the Raritan River in New Jersey are examples of vertically homogeneous estuaries. Inverse estuaries occur in dry climates where evaporation greatly exceeds the inflow of freshwater. A salinity maximum zone

1248-436: A wholly marine embayment to any of the other estuary types. The most important variable characteristics of estuary water are the concentration of dissolved oxygen, salinity and sediment load. There is extreme spatial variability in salinity, with a range of near-zero at the tidal limit of tributary rivers to 3.4% at the estuary mouth. At any one point, the salinity will vary considerably over time and seasons, making it

1344-477: A wide effect on the surrounding water bodies.  In turn, this can decrease fishing industry sales in one area and across the country. Production in 2016 from recreational and commercial fishing contributes billions of dollars to the United States' gross domestic product (GDP). A decrease in production within this industry can affect any of the 1.7 million people the fishing industry employs yearly across

1440-455: Is a dynamic ecosystem having a connection to the open sea through which the sea water enters with the rhythm of the tides . The effects of tides on estuaries can show nonlinear effects on the movement of water which can have important impacts on the ecosystem and waterflow. The seawater entering the estuary is diluted by the fresh water flowing from rivers and streams. The pattern of dilution varies between different estuaries and depends on

1536-513: Is derived from the Latin word aestuarium meaning tidal inlet of the sea, which in itself is derived from the term aestus , meaning tide. There have been many definitions proposed to describe an estuary. The most widely accepted definition is: "a semi-enclosed coastal body of water, which has a free connection with the open sea, and within which seawater is measurably diluted with freshwater derived from land drainage". However, this definition excludes

1632-411: Is formed, and both riverine and oceanic water flow close to the surface towards this zone. This water is pushed downward and spreads along the bottom in both the seaward and landward direction. Examples of an inverse estuary are Spencer Gulf , South Australia, Saloum River and Casamance River , Senegal. Estuary type varies dramatically depending on freshwater input, and is capable of changing from

1728-566: Is less restricted, and there is a slow but steady exchange of water between the estuary and the ocean. Fjord-type estuaries can be found along the coasts of Alaska , the Puget Sound region of western Washington state , British Columbia , eastern Canada, Greenland , Iceland , New Zealand, and Norway. These estuaries are formed by subsidence or land cut off from the ocean by land movement associated with faulting , volcanoes , and landslides . Inundation from eustatic sea-level rise during

1824-448: Is located in the state of Rio Grande do Sul. Riograndia , a cynodont from these deposits, was named after the state in 2001. Other animals from Caturrita Formation include a dicynodont Jachaleria , a traversodontid Exaeretodon and a rhynchosaur Scaphonyx . The presence of Exaeretodon and Scaphonyx shows the relationships with the fauna of Ischigualasto Formation of Argentina while Jachaleria better correlates with

1920-660: Is one of the most important rivers of the state, rising in the ranges of the Coxilha Grande of the north and flowing south and southeast to the Guaíba estuary, with a course of nearly 480 kilometres (300 mi) It has two large tributaries, the Vacacaí from the south and the Taquari from the north, and many small streams. The Jaguarão, which forms part of the boundary line with Uruguay, is navigable 42 km up to and beyond

2016-643: Is the participation of its servicemen in both the coup attempt of 1961 and the military coup in 1964. According to the IBGE of 2022, there were 10,882,965 people residing in the state. The population density was 38.63 inhabitants per square kilometre (100.1/sq mi). Urbanization: 81% (2004); population growth: 1.2% (1991–2000); houses: 3,464,544 (2005). The last 2022 census counted 8,534,229 white people (78.4%), 1,596,357 brown ( Multiracial ) people (14.7%), 709,837 black people (6.5%), 34,184 Amerindian people (0.3%), 8,158 Asian people (0.1%). According to

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2112-646: Is the whitefish species from the European Alps . Eutrophication reduced the oxygen levels in their habitats so greatly that whitefish eggs could not survive, causing local extinctions. However, some animals, such as carnivorous fish, tend to do well in nutrient-enriched environments and can benefit from eutrophication. This can be seen in populations of bass or pikes. Eutrophication can affect many marine habitats which can lead to economic consequences. The commercial fishing industry relies upon estuaries for approximately 68 percent of their catch by value because of

2208-521: Is well distributed throughout the year, but occasional droughts can occur. The winter months, June to September, are characterized by heavy rains and by a cold southwesterly wind, called minuano , which sometimes lowers the temperature to below freezing, especially in the mountainous municipalities , where snowfalls can occur. The lowest official temperature registered in the state was −9.8 °C (14 °F) in Bom Jesus , on August 1, 1955. In summer,

2304-748: The Holocene Epoch has also contributed to the formation of these estuaries. There are only a small number of tectonically produced estuaries; one example is the San Francisco Bay , which was formed by the crustal movements of the San Andreas Fault system causing the inundation of the lower reaches of the Sacramento and San Joaquin rivers . In this type of estuary, river output greatly exceeds marine input and tidal effects have minor importance. Freshwater floats on top of

2400-610: The Mandovi estuary in Goa during the monsoon period. As tidal forcing increases, river output becomes less than the marine input. Here, current induced turbulence causes mixing of the whole water column such that salinity varies more longitudinally rather than vertically, leading to a moderately stratified condition. Examples include the Chesapeake Bay and Narragansett Bay . Tidal mixing forces exceed river output, resulting in

2496-640: The Mid-Atlantic coast, and Galveston Bay and Tampa Bay along the Gulf Coast . Bar-built estuaries are found in a place where the deposition of sediment has kept pace with rising sea levels so that the estuaries are shallow and separated from the sea by sand spits or barrier islands. They are relatively common in tropical and subtropical locations. These estuaries are semi-isolated from ocean waters by barrier beaches ( barrier islands and barrier spits ). Formation of barrier beaches partially encloses

2592-522: The Paraguayan War , known in Portuguese as Guerra do Paraguai. In the war against Rosas, 75% of the Brazilian troops were gaúchos . As the only Brazilian boundaries actually facing foreign armies able to project the Empire's power, Rio Grande do Sul and its gaúchos quickly developed a reputation as soldiers. During this long and bloody war against Paraguay, Rio Grande do Sul remained usually

2688-595: The Paraguayan War . Large waves of German and Italian migration have shaped the state as well. Rio Grande do Sul is bordered to the northeast by the Brazilian State of Santa Catarina , to the southeast by the Atlantic Ocean, on the southwest by Uruguay , and to the northwest by the Argentine provinces of Corrientes and Misiones . The northern part of the state lies on the southern slopes of

2784-741: The Serra do Mar on the Atlantic coast, and the Uruguay River forms the northern and western boundary line of the state down to the mouth of the Quaraí, on the Uruguayan frontier. Rio Grande do Sul lies within the south temperate zone and is predominantly humid subtropical ( Cfa , according to the Köppen climate classification ). The climate is subtropical highland ( Cfb ) in the highest areas. There are four relatively well-defined seasons and rainfall

2880-734: The Severn Estuary in the United Kingdom and the Ems Dollard along the Dutch-German border. The width-to-depth ratio of these estuaries is typically large, appearing wedge-shaped (in cross-section) in the inner part and broadening and deepening seaward. Water depths rarely exceed 30 m (100 ft). Examples of this type of estuary in the U.S. are the Hudson River , Chesapeake Bay , and Delaware Bay along

2976-478: The black-tailed godwit , rely on estuaries. Two of the main challenges of estuarine life are the variability in salinity and sedimentation . Many species of fish and invertebrates have various methods to control or conform to the shifts in salt concentrations and are termed osmoconformers and osmoregulators . Many animals also burrow to avoid predation and to live in a more stable sedimental environment. However, large numbers of bacteria are found within

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3072-687: The 19th and the early 20th centuries. According to the treaty of Tordesillas , the region was to be part of the Spanish possessions in South America. However, the Spanish were much more interested in the Pacific Coast, where gold, silver, and gems were quickly found. Even in the Atlantic coast, their attention was on the River Plate where they built the seaport of Buenos Aires, on its right bank. Consequently, Spanish settlement followed

3168-475: The Empire was able to control most of the coastal region, achieving decisive strategic advantage from this. However, in 1839, the rebels were still able to invade Santa Catarina, where they proclaimed a Juliana Republic , in a federal relationship with Rio Grande do Sul (during the Santa Catarina campaign, Giuseppe Garibaldi joined the rebels for a while before he returned to Europe and eventually became

3264-833: The Italians settled in the Serra Gaúcha, and most of the Germans in the valleys of the Jacuí, Sinos, and Caí, as small landed proprietors, and agricultural producers. In the area of German settlements, a messianic movement, the Muckers (German for False Saints) erupted in 1874, and was smashed by the Brazilian Army. Also during this period, the Liberal Party established its hegemony over the province, meaning control of

3360-597: The Jesuits were back in the region, having refounded seven reductions, the Misiones Orientales . The region remained under Spanish sovereignty, though in practice the Jesuits operated quite independently as consequence of the spanish laws, up to the late 17th century. But in 1680, the Portuguese founded Colônia do Sacramento on the northern bank of the River Plate, in what is now Uruguay . War ensued and

3456-790: The Lagoa dos Patos, and the Jaguarão which flows into the Lagoa Mirim. All of the first named, except the Camaquã, discharge into one of the two arms or estuaries opening into the northern end of Lagoa dos Patos, which is called the Guaíba River , though technically it is not a river but a lake. The Guaíba River is broad, comparatively deep and about 56 kilometres (35 mi) long, and with the rivers discharging into it affords upwards of 320 kilometres (200 mi) of fluvial navigation. The Jacuí

3552-406: The Portuguese. The capture of Rio Grande in 1763 caused the removal of the seat of government to Viamão at the head of Lagoa dos Patos; in 1773, Porto dos Cazaes, renamed Porto Alegre , became the capital. These historic acts were planned and directed by Manuel Sepúlveda, who used the pseudonym José Marcelino de Figueiredo, to hide his identity. In 1801, news of war between Spain and Portugal led to

3648-881: The Provincial President (appointed by the Regency on behalf of the Emperor, who was a minor). Rebellion broke out in the province on September 20, 1835; giving up hope of redress of the situation by the Imperial Government, the gaúchos proclaimed independence of the Riograndense Republic on September 11, 1836. The ensuing Farroupilha Revolution (known locally as Guerra dos Farrapos ) lasted ten years. The rebels stormed Porto Alegre, but were driven out from there in June 1836. From then on,

3744-628: The Serra do Mar is occupied by the Araucaria moist forests , a subtropical forests characterized by evergreen, laurel-leaved forests interspersed with emergent Brazilian Pines (Araucaria angustifolia) . The Alto Paraná Atlantic forests lie on the lower slopes of the plateau south and east of the Araucaria forests, including much of the lower basin of the Jacuí and its tributaries. These forests are semi-deciduous, with many trees losing their leaves in

3840-454: The South") is a state in the southern region of Brazil . It is the fifth-most populous state and the ninth-largest by area . Located in the southernmost part of the country, Rio Grande do Sul is bordered clockwise by Santa Catarina to the north and northeast, the Atlantic Ocean to the east, the Uruguayan departments of Rocha , Treinta y Tres , Cerro Largo , Rivera , and Artigas to

3936-516: The State also have significant numbers of people of both Italian and German descent. There are sizeable communities of Poles and Ukrainians across the state, notably in the northwest. People of African ancestry are concentrated in the capital city and in some cities in the litoral, such as Pelotas and Rio Grande . Estuary Most existing estuaries formed during the Holocene epoch with

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4032-400: The United States. Estuaries are incredibly dynamic systems, where temperature, salinity, turbidity, depth and flow all change daily in response to the tides. This dynamism makes estuaries highly productive habitats, but also make it difficult for many species to survive year-round. As a result, estuaries large and small experience strong seasonal variation in their fish communities. In winter,

4128-687: The Uruguay, the largest are the Ijuí of the plateau region, the Ibicuí , which has its source near Santa Maria in the central part of the state and flows westward to the Uruguay a short distance above Uruguaiana , and the Quaraí River which forms part of the boundary line with Uruguay. The Uruguay River itself is formed by the confluence of the Canoas and Pelotas rivers. The Pelotas, which has its source in

4224-679: The Vargas dictatorship in 1937 and the period known as the Estado Novo . What is now the Rio Grande do Sul Military Brigade fought on the side of the state leadership and, as a result, was never reformed. In fact, the Brigade remains the only state militia in Brazil. (The Military Police is the federal force that polices in the other states.) A poignant example of the Brigade's quasi-autonomy

4320-614: The beginning of the 19th century, wheat was the main export product of Rio Grande do Sul. However, the introduction of charqueadas in the Southern coast, following the 1777 drought in Ceará , opened new opportunities to husbandry, as from them on, instead of moving herds by land to São Paulo, cattle could be sold in the relatively nearby region of Pelotas, to be slaughtered and processed there, and further transported by sea to Santos, Rio de Janeiro, and other Brazilian harbours. The cheap jerky

4416-452: The bottom where they are harmless. Historically the oysters filtered the estuary's entire water volume of excess nutrients every three or four days. Today that process takes almost a year, and sediment, nutrients, and algae can cause problems in local waters. Some major rivers that run through deserts historically had vast, expansive estuaries that have been reduced to a fraction of their former size, because of dams and diversions. One example

4512-817: The capture of the Sete Povos and some frontier posts. In 1777, the Santo Ildefonso Treaty granted the coastal region to Portugal, and the Missões to Spain; but, in practice, both regions were populated by Portuguese and Brazilian settlers. In 1801, the Badajoz treaty handed the Misiones (Missões) to the Portuguese; only the borders between modern Uruguay and Rio Grande do Sul remained in dispute. The districts of Santa Catarina and Rio Grande had been separated in 1760 for military convenience, and in 1807

4608-405: The coastline, northeast and southwest, and is about 214 kilometres (133 mi) long exclusive of the two arms at its northern end, 40 58 km long respectively, and of its outlet, the Rio Grande, about 39 km long. Its width varies from 35 to 58 km. The lake is comparatively shallow and filled with sand banks, making its navigable channels tortuous and difficult. The Lagoa Mirim occupies

4704-477: The course of the River Plate and its tributaries, especially the Paraná and Uruguay rivers, largely ignoring the Rio Grande do Sul area. The Spanish introduced livestock which escaped into the plains and attracted gauchos to the area. The first Spanish to settle in the region that is now Paraguay , northwestern Argentina ( Corrientes , Misiones ), and Rio Grande do Sul were Jesuit missionary priests who came with

4800-409: The dissolved oxygen from the water; thus hypoxic or anoxic zones can develop. Nitrogen is often the lead cause of eutrophication in estuaries in temperate zones. During a eutrophication event, biogeochemical feedback decreases the amount of available silica . These feedbacks also increase the supply of nitrogen and phosphorus, creating conditions where harmful algal blooms can persist. Given

4896-401: The effects of modifying the estuarine circulation. Fjord -type estuaries are formed in deeply eroded valleys formed by glaciers . These U-shaped estuaries typically have steep sides, rock bottoms, and underwater sills contoured by glacial movement. The estuary is shallowest at its mouth, where terminal glacial moraines or rock bars form sills that restrict water flow. In the upper reaches of

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4992-452: The elevated plateau extending southward from São Paulo across the states of Paraná and Santa Catarina, and is much broken by low mountain ranges whose general direction across the trend of the slope gives them the appearance of escarpments. A range of low mountains extends southward from the Serra do Mar of Santa Catarina and crosses the state into Uruguay. West of this range is a vast grassy plain devoted principally to stock-raising –

5088-442: The end of the conflict. In 1923, civil war again exploded between supporters of State President Borges de Medeiros and opposition linked to the Partido Libertador and Assis Brasil . In 1930, State President Getúlio Vargas , after unsuccessfully running in the presidential elections against the candidate of São Paulo, Júlio Prestes, led a revolt against the Federal government, and succeeded in overthrowing it. This eventually led to

5184-543: The estuary impacted by human activities, and over time may shift the basic composition of the ecosystem, and the reversible or irreversible changes in the abiotic and biotic parts of the systems from the bottom up. For example, Chinese and Russian industrial pollution, such as phenols and heavy metals, has devastated fish stocks in the Amur River and damaged its estuary soil. Estuaries tend to be naturally eutrophic because land runoff discharges nutrients into estuaries. With human activities, land run-off also now includes

5280-424: The estuary, the depth can exceed 300 m (1,000 ft). The width-to-depth ratio is generally small. In estuaries with very shallow sills, tidal oscillations only affect the water down to the depth of the sill, and the waters deeper than that may remain stagnant for a very long time, so there is only an occasional exchange of the deep water of the estuary with the ocean. If the sill depth is deep, water circulation

5376-720: The estuary, with only narrow inlets allowing contact with the ocean waters. Bar-built estuaries typically develop on gently sloping plains located along tectonically stable edges of continents and marginal sea coasts. They are extensive along the Atlantic and Gulf coasts of the U.S. in areas with active coastal deposition of sediments and where tidal ranges are less than 4 m (13 ft). The barrier beaches that enclose bar-built estuaries have been developed in several ways: Fjords were formed where Pleistocene glaciers deepened and widened existing river valleys so that they become U-shaped in cross-sections. At their mouths there are typically rocks, bars or sills of glacial deposits , which have

5472-439: The fall, in 1843, of important rebel strongholds, Caçapava do Sul , Bagé , and Alegrete . Economically exhausted and militarily defeated, the rebels accepted Caxias' terms of surrender. A general amnesty was declared, the rebellious officials were incorporated into the Imperial Army, slaves enrolled in the rebel Army were freed. Additionally, the Empire imposed a 25% tax on foreign jerky imports. The province suffered greatly in

5568-609: The fish community is dominated by hardy marine residents, and in summer a variety of marine and anadromous fishes move into and out of estuaries, capitalizing on their high productivity. Estuaries provide a critical habitat to a variety of species that rely on estuaries for life-cycle completion. Pacific Herring ( Clupea pallasii ) are known to lay their eggs in estuaries and bays, surfperch give birth in estuaries, juvenile flatfish and rockfish migrate to estuaries to rear, and anadromous salmonids and lampreys use estuaries as migration corridors. Also, migratory bird populations, such as

5664-498: The flooding of river-eroded or glacially scoured valleys when the sea level began to rise about 10,000–12,000 years ago. Estuaries are typically classified according to their geomorphological features or to water-circulation patterns. They can have many different names, such as bays , harbors , lagoons , inlets , or sounds , although some of these water bodies do not strictly meet the above definition of an estuary and could be fully saline. Many estuaries suffer degeneration from

5760-401: The following day. But if the territory of Rio Grande do Sul was spared most action, its dwellers provided a very significant part of the Brazilian troops: about 34,000 soldiers, more than 25% of the Brazilian army. This military characteristic of Rio Grande do Sul lasted long after the Paraguayan War: In 1879, of a standing army of less than 15,000, more than 5,000 were in Rio Grande do Sul. On

5856-400: The great biodiversity of this ecosystem. During an algal bloom , fishermen have noticed a significant increase in the quantity of fish. A sudden increase in primary productivity causes spikes in fish populations which leads to more oxygen being utilized. It is the continued deoxygenation of the water that then causes a decline in fish populations. These effects can begin in estuaries and have

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5952-460: The historical knowledge about the region. In fact, there was always some Spanish colonial presence there, however in practice restricted to Jesuit religious initiatives towards the Amerindian populations, which had limited genetic impact in the demographic composition of aboriginal populations. On the other hand, it is broadly accepted that it is northern Uruguay that always has had an important Luso-Brazilian influence, which in fact impacts to this day

6048-494: The idea of converting the indigenous population to Catholic Christianity . To that end, they founded missionary villages known in Spanish as misiones or reducciones , populated by Guarani Indians . In the early 17th century, the Jesuits founded missions to the east of the Uruguay river, and in the northwest of modern Rio Grande do Sul. The missions were destroyed and their Guarani inhabitants were enslaved in large raids by bandeirantes between 1636 and 1638; however, in 1687,

6144-420: The impacts do not end there. Plant death alters the entire food web structure which can result in the death of animals within the afflicted biome . Estuaries are hotspots for biodiversity , containing a majority of commercial fish catch, making the impacts of eutrophication that much greater within estuaries. Some specific estuarine animals feel the effects of eutrophication more strongly than others. One example

6240-421: The latter was elevated to the category of a "capitania-geral", with the designation of "Sao Pedro do Rio Grande", independent of Rio de Janeiro, and with Santa Catarina as a dependency. In 1812 Rio Grande and Santa Catarina were organized into two distinct comarcas , the latter becoming an independent province in 1822 when the Empire of Brazil was organized. In 1816, the Portuguese captured Uruguay, which became

6336-438: The lower part of Los Colorados Formation . All three genera confirm the Late Triassic age of the deposits, older than the upper section of Los Colorados Formation. During the Brazilian Colonial period, the province of South Rio Grande was the scene of small wars and border skirmishes between Portugal and Spain for the region, the Sacramento Colony , and the Guarani Missions . It was also a focal point for internal rebellions in

6432-525: The many chemicals used as fertilizers in agriculture as well as waste from livestock and humans. Excess oxygen-depleting chemicals in the water can lead to hypoxia and the creation of dead zones . This can result in reductions in water quality, fish, and other animal populations. Overfishing also occurs. Chesapeake Bay once had a flourishing oyster population that has been almost wiped out by overfishing. Oysters filter these pollutants, and either eat them or shape them into small packets that are deposited on

6528-422: The marine environment, such as plastics , pesticides , furans , dioxins , phenols and heavy metals . Such toxins can accumulate in the tissues of many species of aquatic life in a process called bioaccumulation . They also accumulate in benthic environments, such as estuaries and bay muds : a geological record of human activities of the last century. The elemental composition of biofilm reflect areas of

6624-575: The marsh causing increased rates of erosion . A similar phenomenon occurs in mangrove swamps , which are another potential ecosystem in estuaries. An increase in nitrogen causes an increase in shoot growth and a decrease in root growth. Weaker root systems cause a mangrove tree to be less resilient in seasons of drought, which can lead to the death of the mangrove. This shift in above ground and below ground biomass caused by eutrophication could hindered plant success in these ecosystems. Across all biomes, eutrophication often results in plant death but

6720-493: The mixed Spanish-Portuguese language of northern Uruguay along the border with Brazil (borderlands). People of German descent predominate in the Sinos Valley ( Novo Hamburgo , São Leopoldo , Nova Hartz, Dois Irmãos, Morro Reuter, etc.) and in the center-eastern part of the State ( Santa Cruz do Sul ). People of Italian descent predominate in the mountains ( Serra Gaúcha : Caxias do Sul , Bento Gonçalves , Farroupilha , Garibaldi , etc.). The Northern and Northwestern parts of

6816-401: The northern and most elevated part being suitable in pasturage and climate for sheep, and the southern for cattle. East of it is a wide coastal zone only slightly elevated above the sea; within it are two great estuarine lagoons, the Lagoa dos Patos and Lagoa Mirim , which are separated from the ocean by two sandy, partially barren peninsulas. The coast is one great sand beach, broken only by

6912-440: The now off-balance nitrogen cycle , estuaries can be driven to phosphorus limitation instead of nitrogen limitation. Estuaries can be severely impacted by an unbalanced phosphorus cycle, as phosphorus interacts with nitrogen and silica availability. With an abundance of nutrients in the ecosystem, plants and algae overgrow and eventually decompose, which produce a significant amount of carbon dioxide. While releasing CO 2 into

7008-505: The other hand, during the late Empire, more Brazilian generals were from Rio Grande do Sul than from any other province. In 1889, of 25 generals born in Brazil, four were from Rio Grande do Sul; and of the three born abroad, two were born in Uruguay but made their careers in Rio Grande do Sul. Political agitation was frequent in Rio Grande do Sul, but no important revolution occurred after the Ponche Verde Treaty in 1845 until

7104-598: The outlet of the two lakes, called the Rio Grande, which affords an entrance to navigable inland waters and several ports. There are two distinct river systems in Rio Grande do Sul – that of the eastern slope draining to the lagoons, and that of the Río de la Plata basin draining westward to the Uruguay River . The larger rivers of the eastern group are the Jacuí , Sinos , Caí , Gravataí and Camaquã , which flow into

7200-400: The population there was a result from the mixture of Spanish and Portuguese men with Amerindian women with a possible predominant Spanish ancestry and also a significant African contribution, resulting in a population that is 81.20% White. These theoretical speculations about Spanish predominance among the population of Southwestern Rio Grande do Sul are widely presumed, but they contradict

7296-452: The presidency at Rio de Janeiro of General Floriano Peixoto , whose ill-considered interference with state governments led to the revolt of 1892–94, under Gumercindo Saraiva . After the Paraguayan War , Rio Grande do Sul underwent important changes in its economy. Railways connected the countryside to Porto Alegre and Rio Grande. Together with the introduction of steam ships, this reduced the costs and duration of transportation, facilitating

7392-401: The province's exports. New cattle breeds were introduced, and barbed wire was used to demarcate properties. As a consequence, the population of the province doubled between 1872 and 1890, from 434,813 inhabitants to 897,455. This was partly due to immigration: about 60,000 immigrants, mostly from Italy, and, in lesser numbers, from Germany, came to Rio Grande do Sul during this period. Most of

7488-736: The provincial legislature, the National Guard in Rio Grande do Sul, and most of the municipal governments. Before the War of the Triple Alliance, the Conservative and Liberal parties had alternated in local power, following the national tendency. But, from 1872 on, the Liberals, under the leadership of Gaspar da Silveira Martins , were able to retain provincial power, even when the Conservatives won at national level. In this struggle

7584-538: The region came definitely into Portuguese hegemony. In 1738, the territory (which included the present state of Santa Catarina) became the Capitania d'el Rei and was made a dependency of Rio de Janeiro. Territorial disputes between Spain and Portugal led to the occupation by the Spaniards of the town of Rio Grande (then the capital of the capitania) and neighboring districts from 1763 to 1776, when they reverted to

7680-721: The regional elites soon started to demand customs protection for the gaúcho jerky against the product of the Rio de la Plata; on the failure of the Imperial government to address those concerns, political demands of greater autonomy, and ideas of a federal relationship towards the rest of Brazil were put forth. These escalated into full rebellion in 1835. In 1834, the Imperial government issued an " Ato Adicional ", allowing for elected Provincial legislative assemblies. The first gaúcha Legislative Assembly, inaugurated in April 1835, quickly confronted

7776-466: The remains of an ancient depression in the coastline shut in by sand beaches built up by the combined action of wind and current. They are of the same level as the ocean, but their waters are affected by the tides and are brackish only a short distance above the Rio Grande outlet. Fully one-third of the state belongs to the Río de la Plata drainage basin. Of the many streams flowing northward and westward to

7872-406: The revolutionaries occupied Santa Catarina and Paraná, capturing Curitiba , but were eventually overthrown through their inability to obtain munitions of war. An incident in this struggle was the death of Admiral Saldanha da Gama , one of the most brilliant officers of the Brazilian navy and one of the chiefs of the naval revolt of 1893–94, who was killed in a skirmish on the Uruguayan border towards

7968-427: The seawater in a layer that gradually thins as it moves seaward. The denser seawater moves landward along the bottom of the estuary, forming a wedge-shaped layer that is thinner as it approaches land. As a velocity difference develops between the two layers, shear forces generate internal waves at the interface, mixing the seawater upward with the freshwater. An examples of a salt wedge estuary is Mississippi River and

8064-411: The sediment which has a very high oxygen demand. This reduces the levels of oxygen within the sediment often resulting in partially anoxic conditions, which can be further exacerbated by limited water flow. Phytoplankton are key primary producers in estuaries. They move with the water bodies and can be flushed in and out with the tides . Their productivity is largely dependent upon the turbidity of

8160-481: The south and southwest, and the Argentine provinces of Corrientes and Misiones to the west and northwest. The capital and largest city is Porto Alegre . The state has the highest life expectancy in Brazil, and the crime rate is relatively low compared to the Brazilian national average. The state has 5.4% of the Brazilian population and it is responsible for 6.6% of the Brazilian GDP. The state shares

8256-874: The struggle, but recovered quickly, not only due to the import tax protection, but mainly due to renewed instability in Argentina and Uruguay: Rosas' government in Argentina continually interfered in Uruguayan affairs until 1851, and Buenos Aires was blockaded by the French and the English from 1845 to 1848. At mid-19th century, Rio Grande do Sul was repeatedly involved in war between Brazil and its neighbours. Those included war against Argentina and Uruguay (deposal of Juan Manuel Rosas , Argentinian dictator, and Manuel Ceferino Oribe y Viana , Uruguayan president, 1852) and intervention in Uruguay (deposal of Atanasio Cruz Aguirre , 1864). This, in turn, led to Paraguayan intervention, and

8352-453: The temperature rises to 37 °C (99 °F), and heat related injuries are not uncommon. Several ecoregions cover portions of the state. In the northeastern corner of the state, between the Serra do Mar /Serra Geral and the Atlantic, lies the southern extension of the Serra do Mar coastal forests , a belt of evergreen tropical moist forests that extend north along the coastal strip as far as Rio de Janeiro state . The high plateau behind

8448-479: The town of Jaguarão . In addition to the Lagoa dos Patos and Lagoa Mirim there are a number of small lakes on the sandy, swampy peninsulas that lie between the coast and these two, and there are others of a similar character along the northern coast. The largest lake is the Lagoa dos Patos (Lake of the Patos ;– an Indian tribe inhabiting its shores at the time of European discovery), which lies parallel with

8544-456: The volume of freshwater, the tidal range, and the extent of evaporation of the water in the estuary. Drowned river valleys are also known as coastal plain estuaries. In places where the sea level is rising relative to the land, sea water progressively penetrates into river valleys and the topography of the estuary remains similar to that of a river valley. This is the most common type of estuary in temperate climates. Well-studied estuaries include

8640-453: The water and atmosphere, these organisms are also intaking all or nearly all of the available oxygen creating a hypoxic environment and unbalanced oxygen cycle . The excess carbon in the form of CO 2 can lead to low pH levels and ocean acidification , which is more harmful for vulnerable coastal regions like estuaries. Eutrophication has been seen to negatively impact many plant communities in estuarine ecosystems . Salt marshes are

8736-835: The water. The main phytoplankton present are diatoms and dinoflagellates which are abundant in the sediment. A primary source of food for many organisms on estuaries, including bacteria , is detritus from the settlement of the sedimentation. Of the thirty-two largest cities in the world in the early 1990s, twenty-two were located on estuaries. As ecosystems, estuaries are under threat from human activities such as pollution and overfishing . They are also threatened by sewage, coastal settlement, land clearance and much more. Estuaries are affected by events far upstream, and concentrate materials such as pollutants and sediments. Land run-off and industrial, agricultural, and domestic waste enter rivers and are discharged into estuaries. Contaminants can be introduced which do not disintegrate rapidly in

8832-467: The west, Rio Pardo was also founded. Towards the middle of the century, Brazilians and Portuguese arrived to the west of the region, clashing with the Jesuits and the Guaranis. Up to 1756, the Guaranis fought back, under the leadership of Sepé Tiaraju , who was popularly canonized as São Sepé (Saint Sepé). However, the Portuguese and Brazilians eventually crushed the resistance, destroyed the missions, and

8928-567: The winter dry season. The Atlantic Coast restingas , distinctive forests which grow on nutrient-poor coastal dunes, extend along the coast, as far as the Uruguayan border. The southeastern portion of the state is covered by the Pampas , which extends south into Uruguay , in a plateau named Serras de Sudeste (Southeastern Mountain Ranges). The Caturrita Formation , rich in Triassic fossils,

9024-547: Was commonly used as food for the enslaved laborers in other parts of Brazil. Up to 1830, political unrest in Argentina and Uruguay favoured the jerky producers of Pelotas. But with order restored in these countries, competition by Argentinian and Uruguayan jerky producers became a concern. The jerky industry of the Plata was favored by the superior quality of Argentinian and Uruguayan pastures, by their better seaports, and by their use of free labor, instead of slavery. Consequently,

9120-405: Was intermittent until the independence of Uruguay in 1828. The logistics of defending Colônia against the Spanish resulted in a government effort to settle Rio Grande do Sul's coastal region with Brazilian and Portuguese colonists. In 1737, a fortified village (today the city of Rio Grande) was built at the entrance of Lagoa dos Patos. In 1752, a group of Azorean settlers founded Porto Alegre; to

9216-419: Was the predominant economic activity. The Guaranis, under Jesuit rule, had started raising cattle in the Missões. The destruction of the Missões left astray immense herds, which went feral. Thus the newcomers from São Paulo and Santa Catarina settled by re-domesticating these feral herds, called "gado xucro". The Azorean settlers, on the other hand, mainly introduced wheat crops in much smaller properties. Up to

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