savejungle / shutterstock
The Pantanal is the largest floodplain of the entire planet at an average altitude of 100 meters above sea level. His area of over 210 square kilometers covers territories of Mato Grosso, Mato Grosso do Sul, Bolivia and Paraguay, and has one of the richest biodiversity in the world.
The Pantanal characteristics with respect to temperature, humidity, altitude, ground and presence of life qualify it as a more natural biome that may form on earth. And this unique paradise exists because of a specific series of geological episodes.
Pantanal: how it formed?
Andrea Danti / Shutterstock
The most accepted theory among geologists is that the Pantanal is a side result of the formation of the Andes. Professor Mario Sign of the Institute of Geosciences and Exact Sciences Unesp, explains in his article "Pantanal Mato Grosso: a geological gift" this thesis argues that the compression movement and strain of the Andes would have interfered with the establishment of the high plain - the area would have suffered an overload and then rose.
The alternative hypothesis the Andes is that the magmatic mantle beneath the Earth's surface would have experienced an anomaly. This anomaly would have caused the uplift of the upper crust, forming the Pantanal as we know it.
No one knows for sure how the phenomenon occurred, but there is consensus that occurred in the Cenozoic geological period. "We do not know exactly when it started, but it [training] active today. The Pantanal wetland has undergone many changes in the tens of thousands of years, because the weather changed. It was not always as it is today. There were times when there was so much water, "explains Mario Sign.
Why Pantanal floods?
FCG / Shutterstock
The Pantanal is part of what geologists call the geomorphological unit of the Upper Paraguay Depression, a soil sedimentation and complex river basin located in the middle of América do Sul.
The Upper Paraguay Depression consists of several units. Among them all, the Pantanal is one of the newest and lower, which creates conditions for the famous seasonal floods for which the region is.
"The Pantanal is a great natural system, made up of different sub-basins. It has been divided into different wetlands, especially because different areas have unique characteristics, especially regarding the nature and flood period, "he wrote Professor Mario Luis Subscribe in their study.
These various wetland cutouts are composed of alluvial fans, which are sedimentary formations with irregular formation in a format similar to that range. The greatest of them all is the megafan the Taquri, approximately 50,000 km²m, equivalent to 37% of the entire biome. What gives unity to all of them is exactly the main water source: the trunk of the Paraguay River.
Uwe Bergwitz / Shutterstock
The wetland biodiversity is huge. The flora has at least 3500 species of plants and wildlife is also extremely complex: are cataloged 124 species of mammals, 463 of birds and 325 of fish, and thousands of insects.
Two factors explain this diversity. First the geological nature of the biome, allowing large tracts of wetlands, sites conducive to various forms of plant and animal life. And also by the geographical position, since the Pantanal is located at the meeting of three major biomes: Amazon to the north, east and northeast Cerrado and Steppe Chaqueña southwest.
Ondrej Prosicky / Shutterstock
alluvial systems, such as the Pantanal, has a surface structure which, on its own sediment composition, change constantly. Particularly in areas close to rivers, after their periods of drought and flood fill or empty the sediments that make up the Pantanal soil.
"These changes are induced by cyclical processes, such as tectonic movements and climate change. Therefore, the landscape of the Pantanal is continually changing, "concluded the geologist.
Nature of Brazil
- How did the Iguaçu Falls: meeting of volcanic lava and river
- Maranhenses: why the dunes move with the wind?
- Guarani Aquifer: how it formed the huge ocean under our feet?