|Tocantins-Araguaia-Maranhão moist forests
Açailândia in the south of the ecoregion
Ecoregion territory (in purple)
|Tropical and subtropical moist broadleaf forests – Amazon
The Tocantins-Araguaia-Maranhão moist forests (NT0170), also called the Tocantins/Pindaré moist forests, is an ecoregion in the north of Brazil to the south of the mouth of the Amazon River. It is part of the Amazon biome. The ecoregion contains the city of Belém, capital of the state of Pará. It is the most developed part of the Amazon region, and is one of the most severely degraded natural habitats of the region.
The Tocantins-Araguaia-Maranhão Moist Forests ecoregion is the most eastern of the Amazon region. It covers the east of the state of Pará and the north of Maranhão. The main cities are Belém, Paragominas and Bragança.Its western border is the Tocantins River, a tributary of the Amazon River. It is bordered by the mouth of the Amazon to the northwest and the Atlantic Ocean to the northeast. The southern border is defined by the Mearim River. To the east it is bounded by the Pindaré River and the Baía de São Marcos.
The Marajó várzea at the mouth of the Amazon lies to the north. There is a belt of Amazon-Orinoco-Southern Caribbean mangroves along the Atlantic coast to the northeast. To the southeast the ecoregion adjoins the Maranhão Babaçu forests. In the south it meets the cerrado ecoregion and elements of the Mato Grosso seasonal forests. To the west it adjoins the Xingu-Tocantins-Araguaia moist forests on the other side of the Tocantins River.
Most of the region is an alluvial plain formed by the Amazon river. The Serra do Tiracambu and Serra do Gurupi in the southwest are low hills less than 200 metres (660 ft) high. The Gurupí, Capim, and the whitewater Guamá rivers flow into the mouth of the Amazon and are affected by the daily tides, which force water from the Amazon upstream. The Mearim and Pindaré empty into the Atlantic Ocean. Soils are mainly low in nutrients and consist of deeply weathered clay.
The ecoregion is in the Neotropical realm and the tropical and subtropical moist broadleaf forests biome.
The Köppen climate classification is "Am": equatorial, monsoonal. Temperatures are fairly steady throughout the year, slightly cooler in August and slightly warmer in April. Average temperatures range from 22 °C (72 °F) to 32 °C (90 °F) with a mean temperature of 27.5 °C (81.5 °F). The ecoregion experiences a dry season for five months of each year, with monthly rainfall of less than 100 millimetres (3.9 in). This is most marked in the northwest of Maranhão. Rainfall is lowest in September, with less than 50 millimetres (2.0 in), and greatest in March, with over 375 millimetres (14.8 in). During the wet season the streams and rivers expand and flood the low lying regions. Annual rainfall is about 2,500 millimetres (98 in) in the north, and 1,500 millimetres (59 in) in the drier south where the moist forest merges into cerrado shrubland.
The ecoregion may be a diversification center for many taxa of trees, and in the past the west of the region may have been a refugium. There is a wide variety of species in the dense evergreen rainforest due to the many rivers and to the transitional nature of the flora between the Amazon basin and the drier southern vegetation. The ecoregion contains flooded forests and terra firme forests.
The flooded forests are either igapó, flooded daily by clear blackwater rivers, or várzea, flooded daily by whitewater rivers that take their color from suspended soil and organic matter. The igapó forests are adapted to acidic white sand soils that are poor in nutrients. The trees are lower and less diverse than in the terra firme forests. Common species in the igapó and várzea include Caraipa grandiflora , Virola surinamensis , Euterpe oleraceae , Ficus pulchella , Mauritia martiana , Symphonia globulifera , and members of the Tovomita and Clusia genera.
The most common families in the terra firme forests are Lecythidaceae, Chrysobalanaceae, Burseraceae, Fabaceae, Lauraceae and Sapotaceae. Tree species include Lecythis odora , Lecythis turbinata , Cenostigma tocantina , Bombax tocantinum , and Bauhinia bombaciflora , a large liana. The legume Vouacapoua americana is the most important timber tree, growing only in the east of the Amazon region. Brazil nut (Bertholletia excelsa) is uncommon in the region and there are few orchids. The threatened mahogany ( Swietenia macrophylla ) may be found along the upper Capim and Guamá rivers. Other rare or threatened trees include Pilocarpus microphyllus and Dicypellium caryophyllatum .
149 species of mammals have been recorded, of which over 80 are bats. Mammals include red-handed howler (Alouatta belzebul), red-handed tamarin (Saguinus midas), brown-throated sloth (Bradypus variegatus), Linnaeus's two-toed sloth (Choloepus didactylus) and nine-banded armadillo (Dasypus novemcinctus).Endangered mammals include white-cheeked spider monkey (Ateles marginatus), black bearded saki (Chiropotes satanas) and giant otter (Pteronura brasiliensis).
There are more than 76 species of snakes. The rivers have many fish and aquatic reptiles.Endangered reptiles include green sea turtle (Chelonia mydas), hawksbill sea turtle (Eretmochelys imbricata) and Maranhão slider (Trachemys adiutrix).
517 species of birds have been recorded, including two species of heron that are uncommon in other parts of the Amazon region, tricolored heron (Egretta tricolor) and yellow-crowned night heron (Nyctanassa violacea). Other birds include toucans (genus Ramphastos ), red-throated piping guan (Pipile cujubi), white-crested guan (Penelope pileata), parrots, parakeets and many migrant birds from the Nearctic realm.Endangered birds include green-thighed parrot (Pionites leucogaster), red-necked aracari (Pteroglossus bitorquatus) and yellow-bellied seedeater (Sporophila nigricollis).
The Tapajós-Xingu, Xingu-Tocantins-Araguaia and Tocantins/Pindare moist forests ecoregions on the eastern edge of the Amazon basin have all been badly affected by human settlement and deforestation. 2,430 square kilometres (940 sq mi) of low-lying forest. Over a third of the forests have been cleared, often leaving degraded land.The Xingu-Tocantins-Araguaia ecoregion is one of the most developed in the Amazon region, with most of the habitat threatened by cities and highways. There are large industrial and agricultural developments along the roads and colonization along the rivers. The Tucuruí Dam on the Tocantins below Marabá flooded
The result is a patchwork of forest remnants, secondary forests, fields, pastures and urban sprawl. Fires are often used to clear land, threatening the remaining forest ecosystems with their many rare species. Seedlings of rainforest trees cannot grow in the dry and eroded pastures, so forest regeneration is difficult.During the period from 2004 to 2011 the ecoregion experienced an annual rate of habitat loss of 0.51%. Global warming will force tropical species to migrate uphill to find areas with suitable temperature and rainfall. Low, flat and deforested ecoregions such as the Tocantins/Pindare moist forests are extremely vulnerable.
There are a number of small protected areas. The Caxiuanã National Forest covers 2,000 square kilometres (770 sq mi) and offers a degree of protection.
The Tocantins River is a river in Brazil, the central fluvial artery of the country. In the Tupi language, its name means "toucan's beak". It runs from south to north for about 2,450 km. It is not really a branch of the Amazon River, since its waters flow into the Atlantic Ocean alongside those of the Amazon. It flows through four Brazilian states and gives its name to one of Brazil's newest states, formed in 1988 from what was until then the northern portion of Goiás.
The Pindaré River is a river in Maranhão state of north-central Brazil.
The Mearim River is a river in Maranhão state of northern Brazil. The river originates in the southern part of Maranhão, and drains north into the Baía de São Marcos, an estuary that also receives the Pindaré and Grajaú rivers, which are sometimes considered tributaries of the Mearim. The lower Mearim is known for its pororoca, or tidal bore.
Caxiuanã National Forest is a national forest located in lower Amazon region the state of Pará in the North Region of Brazil. It is located on the west banks of the Baía de Caxiuanã between the Xingu River and downstream from the Anapu River. The forest is located southeast of the Ilha do Marajó. Caxiuanã National Forest covers two municipalities in Pará, Portel and Melgaço, but the forest itself is sparsely inhabited. It is located 400 kilometres (250 mi) from the state capitol of Belém.
The Amazon biome contains the Amazon rainforest, an area of tropical rainforest, and other ecoregions that cover most of the Amazon basin and some adjacent areas to the north and east. The biome contains blackwater and whitewater flooded forest, lowland and montane terra firme forest, bamboo and palm forest, savanna, sandy heath and alpine tundra. Some areas are threatened by deforestation for timber and to make way for pasture or soybean plantations.
The Negro-Branco moist forests (NT0143) is an ecoregion of tropical moist broadleaf forest to the east of the Andes in southern Venezuela, eastern Colombia and northern Brazil, in the Amazon biome. It lies on the watershed between the Orinoco and Rio Negro basins. It includes both blackwater and whitewater rivers, creating different types of seasonally flooded forest. The vegetation is more typical of the Guiana region than the Amazon.
The Japurá-Solimões-Negro moist forests (NT0132) is an ecoregion of tropical moist broad leaf forest in the Amazon biome.
The Marajó várzea (NT0138) is an ecoregion of seasonally and tidally flooded várzea forest in the Amazon biome. It covers a region of sedimentary islands and floodplains at the mouth of the Amazon that is flooded twice daily as the ocean tides push the river waters onto the land. The flooded forests provide food for a wide variety of fruit-eating fish, aquatic mammals, birds and other fauna. It has no protected areas and is threatened by cattle and water-buffalo ranching, logging and fruit plantations.
The Gurupa várzea (NT0126) is an ecoregion of seasonally and tidally flooded várzea forest along the Amazon River in the Amazon biome.
The Monte Alegre várzea (NT0141) is an ecoregion of seasonally flooded várzea forest along the Amazon River in the Amazon biome.
The Purus várzea (NT0156) is an ecoregion of seasonally flooded várzea forest in the central Amazon basin. It is part of the Amazon biome. The ecoregion is home to a vegetation adapted to floods of up to 12 metres (39 ft) that may last for eight months. There is a great variety of fish and birds, but relatively fewer mammals. Ground-dwelling mammals must migrate to higher ground during the flood season. Threats include logging, cattle farming, over-fishing and mercury pollution from gold mining.
The Purus-Madeira moist forests (NT0157) is an ecoregion in the central Amazon basin. It is part of the Amazon biome. The ecoregion covers a stretch of flat and relatively infertile land between the Purus and Madeira rivers, extending to the Solimões River in the north. It is isolated from other regions by the seasonally flooded várzea forest along these rivers, and has a high degree of endemism among its flora and fauna. The natural environment is relatively intact. The BR-319 highway was built along the length of the ecoregion in the early 1970s, but rapidly deteriorated and is now closed.
The Madeira-Tapajós moist forests (NT0135) is an ecoregion in the Amazon basin. It is part of the Amazon biome. The ecoregion extends southwest from the Amazon River between its large Madeira and Tapajós tributaries, and crosses the border into Bolivia. In the south it transitions into the cerrado biome of Mato Grosso. In the state of Rondônia it contains some of the most degraded land of the Amazon basin.
The Tapajós-Xingu moist forests (NT0168) is an ecoregion in the eastern Amazon basin. It is part of the Amazon biome. The ecoregion extends southwest from the Amazon River between its large Tapajós and Xingu tributaries.
The Xingu-Tocantins-Araguaia moist forests (NT0180) is an ecoregion in the eastern Amazon basin. It is part of the Amazon biome. The ecoregion is one of the most severely degraded of the Amazon region, suffering from large-scale deforestation and selective extraction of timber, particularly along the Trans-Amazonian Highway and in the higher and more populated southern portions.
The Mato Grosso tropical dry forests (NT0140), also called the Mato Grosso seasonal forests, is an ecoregion in central Brazil to the south of the Amazon region. It contains vegetation in the transition between the Amazon rainforest to the north and the cerrado savanna to the south. The opening of highways through the region has caused rapid population growth, deforestation and pollution.
The Solimões-Japurá moist forests (NT0163) is an ecoregion in northwest Brazil and eastern Peru and Colombia in the Amazon biome. It has a hot climate with high rainforest throughout the year, and holds one of the most diverse collections of fauna and flora in the world. The ecoregion is relatively intact.
The Iquitos várzea (NT0128) is an ecoregion of flooded forest along rivers in Brazil, Peru and Bolivia in the west of the Amazon biome. The forest is seasonally flooded up to 7 metres (23 ft) by whitewater rivers carrying nutrient-rich sediment from the Andes. The meandering rivers often shift course, creating a complex landscape of oxbow lakes, marshes, levees and bars, with grasslands, shrubs and forests in different stages of succession. During the extended flood periods fish enter the forest in search of fruit. The várzea is accessible by the navigable rivers that run through it, and has suffered from extensive deforestation to extract timber and create pasture for livestock.
The Juruá-Purus moist forests (NT0133) is an ecoregion in northwest Brazil in the Amazon biome. The terrain is very flat and soils are poor. The rivers flood annually. There are no roads in the region, and the dense rainforest is relatively intact, although plans to extend the Trans-Amazonian Highway through the region would presumably cause widespread damage to the habitat.
The Amazon-Orinoco-Southern Caribbean mangroves (NT1401) is an ecoregion along the coasts of Colombia, Venezuela, Guyana, Suriname, French Guiana and Brazil.