The Pantanal is a tropical wetland. It is one of the world's largest wetlands of any kind. Most of it lies within the Brazilian state of Mato Grosso do Sul, but it extends into Mato Grosso and portions of Bolivia and Paraguay, sprawling over an area estimated at between 140,000 square kilometres (54,000 sq mi) and 195,000 square kilometres (75,000 sq mi). Various subregional ecosystems exist, each with distinct hydrological, geological and ecological characteristics; up to 12 of them have been defined (RADAMBRASIL 1982).
About 80% of the Pantanal floodplains are submerged during the rainy seasons, nurturing an astonishing biologically diverse collection of aquatic plants and helping support a dense array of animal species. The name "Pantanal" comes from the Portuguese word pântano, meaning wetland, bog, swamp, quagmire or marsh. By comparison, the Brazilian highlands are locally referred to as the planalto, plateau or, literally, high plain.
Geology, Geography and Ecology
The Pantanal is a huge, gently-sloped basin that receives runoff from the upland areas (the Planalto highlands) and slowly releases the water through the Paraguay River and tributaries. The formation is a result of the large, concave pre-Andean depression of the earth's crust, related to the Andean orogeny of the Tertiary. It constitutes an enormous internal river delta, in which several rivers flowing from the surrounding plateau merge, depositing their sediments and erosion residues, which have been filling, throughout the years, the large depression area of the Pantanal. This area is also one of the distinct physiographic provinces of the larger Parana-Paraguay Plain area.
Floodplain ecosystems such as the Pantanal are defined by their seasonal inundation and desiccation. They shift between phases of standing water and phases of dry soil, when the water table can be well below the root region. Soils range from high levels of sand in higher areas to higher amounts of clay and silt in riverine areas. Elevation of the Pantanal ranges from 80 to 150 m (260 to 490 ft) above sea level. Annual rainfall over the flood basin is between 1,000 and 1,500 mm (39 and 59 in), with most rainfall occurring between November and March.
The vegetation of the Pantanal, often referred to as the "Pantanal complex", is a mixture of plant communities typical of a variety of surrounding biome regions: these include moist tropical Amazonian rainforest plants, semiarid woodland plants typical of northeast Brazil, Brazilian cerrado savanna plants and plants of the Chaco savannas of Bolivia and Paraguay.
The Pantanal ecosystem is also thought to be home to 1000 bird species, 400 fish species, 300 mammalian species, 480 reptile species and over 9000 different subspecies of invertebrates. Among the rarest animals to inhabit the wetland of the Pantanal are the marsh deer (Blastocerus dichotomus) and the giant river otter (Pteroneura brasiliensis).
Pantanal Matogrossense National Park
A portion of the Pantanal in Brazil has been protected as the Pantanal Matogrossense National Park. This 1,350 square kilometres (520 sq mi) park, established in September 1981, is located in the municipality of Poconé in the State of Mato Grosso, between the mouths of the Baía de São Marcos and the Gurupi Rivers. This park has been designated a Ramsar Site of International Importance under the Ramsar Convention since May 24, 1993.
SESC Pantanal Private Natural Heritage Reserve
The SESC Pantanal Private Natural Heritage Reserve (Reserva Particular do Patrimonio Natural SESC Pantanal) is a privately owned reserve in Brazil, established in 1998 and 878.7 sq km (339.3 sq mi) in size. It is located in the north-eastern portion, known as "Poconé" Pantanal, not far from the Pantanal National Park. It is a mix of permanent rivers, seasonal streams, permanent and seasonal floodplain freshwater lakes, shrub-dominated wetlands and seasonally flooded forests, all dedicated to nature preservation, and was designated a Ramsar Site of International Importance under the Ramsar Convention.