Pantanal is a sedimentary plain, located on the central region of South America, covering, in Brazil, an area of 168.000 square kilometers, in the states of Mato Grosso and Mato Grosso do Sul. Between the slopes of the central plateau on its eastern, northern and southern sides and elevations pertaining to the Andean system to the west.

Geologically, Pantanal can be described as a depression located in the area of contact between the Brazilian shield and the Andean system, resulting, according to different authors, of the fragmentation or erosion of these structures during the formation of the local relief, begun during Superior Cretaceous period, about 80 millions of years ago. However, the most relevant facts that made possible the colonization of the Pantanal by the flora and fauna observed today happened in the last 30 thousand years, with the development of its relief, hydrography and increased humidity.

The relief presents nowadays modest elevations, round or elongated, and isolated mounts, temporary or permanent drainage channels, flooded plains and lakes.

The main rivers forming the Pantanal are the Paraguai, Cuiabá and São Lourenço on its northern part, and the Taquari, Negro and Miranda on the south

Rains can add up to around 1.400 millimeters a year, with higher concentration between October and March, and lower in August and September.

Average temperature ranges from 24°C to 28°C. The average of the highest temperatures is 32°C and of the lowest, 20°C.

Aaltitude varies from 80 to 110 meters above sea level.

Pantanal's vegetation is composed of hydrophyte (aquatic), hygrophilous (temporarily flooded), mesophyte (medium humidity) and xerophyte (adapted to strong drought) plants, showing a rich mosaic of forests, savannas and grasslands, presenting excellent conditions for local fauna observation, specially birds, of which we see hundreds of species.

The age of archeological sites are estimated in 8 thousand years located in tall banks of Paraguai river, around lakes or on mount slopes, and in 2 thousand years the occupation of floodable areas by indians. In the last 250 years the plain was occupied by cattle-raising farms, the most expressive cultural and economic feature in present days.

The greater risks to the integrity of the Pantanal ecosystems are found in the Paraguai river basin, outside the plain. Mechanized agriculture, through deforestation and erosion, silts the rivers, enlarging the environmental impacts of big floods and polluting the water with pesticides and sub-products of alcohol distilleries. Besides agriculture, gold mining is associated to devastation and contamination by mercury .