The Pantanal is a tropical wetland and the world's largest wetland of any kind. It lies mostly within the Brazilian state of Mato Grosso do Sul but extends into Mato Grosso as well as into portions of Bolivia and Paraguay
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 or marsh. By comparison, the Brazilian highlands are locally referred to as the planalto, plateau or, literally, high plain.
Geology, geography and ecology
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.
The Pantanal is bounded by the Chiquitano dry forests to the west and northwest, by the Arid Chaco dry forests to the southwest, and the Humid Chaco to the south. The Cerrado savannas lie to the north, east, and southeast. The Pantanal has an average yearly rainfall of 1,000–1,400 mm (39–55 in), but is fed by the upper Paraguay River . Its average temperature is 25 °C (77 °F), but temperatures can fluctuate from 0 to 40 °C (32 to 104 °F).
During the rainy season the water in the Pantanal basin rises between two and five meters. Just as the Nile delta is fertile farmable land, so too are the Pantanal plains. The dramatic increase of water during the rainy season nourishes the producers of Pantanal, which in turn nourishes all the other species as well. Humans have taken advantage of this so much that it has become a problem.
Hydrodynamics
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 to 1,500 mm (39 to 59 in) with most rainfall occurring between November and March. In the Paraguay River portion of the Pantanal water levels rise between two meters to five meters seasonally; water fluctuations in other parts of the Pantanal are less than this. Flood waters tend to flow slowly (2 to 10 cm (0.79 to 3.9 in) per second due to the low gradients and high resistance offered by the dense vegetation.
When rising river waters first contacts previously dry soil, the waters become oxygen-depleted, rendering the water environs anoxic. Many natural fish kills can occur if there are no oxygenated water refuges available (the reason for this remains speculative: it may be due to the growth of toxin-producing bacteria in the de-oxygenated water rather than as a direct result of lack of oxygen (McClain 2002).
Flora
The vegetation of the Pantanal is often referred to as the "Pantanal complex" and is a mixture of plant communities typical of a variety of surrounding biome regions: these include moist tropical Amazonian rainforest plants, semi-arid woodland plants typical of northeast Brazil, Brazilian cerrado savanna plants and plants of the Chaco savannas of Bolivia and Paraguay.Forests usually occur at higher altitudes of the region, while grasslands cover the seasonally inundated areas. The key limiting factors for growth are inundation and, even more importantly, water-stress during the dry season. The Pantanal ecosystem is home to 3500 known plant species.
Fauna
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). Parts of the Pantanal are also home to the following endangered or threatened species: the Hyacinth Macaw (Anodorhyncus hyacinthinus) (a bird endangered due to smuggling), the Crowned Solitary Eagle, the Jaguar (Panthera onca), the Maned Wolf (Chrysocyon brachyurus), the Bush Dog (Speothos venaticus), the Capybara (Hydrochoerus hydrochaeris), the South American Tapir (Tapirus terrestris), the Giant Anteater (Myrmecophaga tridactyla) and the Yacare Caiman (Caiman yacare). The Pantanal is home to one of the largest and healthiest Jaguar populations on Earth.
In addition to the caiman, the following reptiles inhabit the Pantanal: the yellow anaconda (Eunectes notaeus), the Gold tegu (Tupinambis teguixin), the red-footed tortoise (Geochelone carbonaria) and the Green Iguana (Iguana Iguana).
Threats to the Pantanal
The Pantanal region includes essential sanctuaries for migratory birds, critical nursery grounds for aquatic life, and refuges for such creatures as the yacare caiman, deer, and jaguar.
The main human activities which threaten the Pantanal ecosystems are:
Commercial fishing
Fishing is focused on only a few species and is probably not sustainable.
National and international sport fishing
The Paraguay river and its tributaries are the main focus for fishing activities.
Cattle-ranching
Approximately 99% of the land in the Pantanal is privately owned for the purpose of agriculture and ranching
There are 2500 fazendas in the region and up to eight million cattle.
Erosion and sedimentation caused by this activity alter the soil and hydrological characteristics of Pantanal flood-plain ecosystems with the consequence that native species are threatened by the change in ecosystem variables.
Hunting and smuggling of endangered species
Reptile, wild cat and parrot species are particularly at risk from the smuggling industry due to their high value on the black market.
Uncontrolled tourism and over use of natural resources.
Deforestation
Deforestation is more relevant to elevated areas of the Pantanal which contain forest stands than low-land grassy areas.
Silt run-off from deforested highlands alters soil hydrology and is a significant threat to the Pantanal.
Mercury pollution from gold mining operations
The Pantanal is a natural water treatment system as it removes chemicals, including pollutants, from water. However, over-pollution from industrial development (especially gold mining) can harm native flora and fauna.
Pollution from agro-industrial plants
However, water quality in the Pantanal was not significantly impacted as of 2002.
Recent high flooding has caused inundation of cultivated areas surrounding the park. The receding flood waters carried large amounts of pesticides back into the rivers and lakes, killing a great number of fish.
Pollution from sewage systems
Development of land for transport (shipping canals and raised roads)
The proposed plan to dredge the Paraguay and Parana Rivers to allow ocean-going ships to travel further inland is of particular concern and could affect the hydrology (flooding and drainage cycles) of the region, and therefore impact the ecosystem.
A portion of the Pantanal in Brazil has been protected as the Pantanal Matogrossense National Park municipality of Poconé in the State of Mato Grosso , between the mouths of the Baía de São Marcos and the Gurupi River
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 Pantanal National Park
Main cities located within the Pantanal region
Miranda, MS
In fiction
John Grisham's novel The Testament largely takes place in the Pantanal.
Pantanal is the title of a Brazilian-produced telenovela whose setting is the Brazilian Pantanal.
The Jack McKinney Robotech novel Before the Invid Storm makes reference to former soldiers of The Army of the Southern Cross called The Pantanal Brigade by the character Major Alice Harper Argus.
The Twilight Saga: The Amazon Coven. "The Amazon coven consists of three sisters, Kachiri, Zafrina, and Senna, all natives of the Pantanal wetlands" - The Twilight Saga: The Official Illustrated Guide p.185.
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