Amazon Rain Forest in the world

The Amazon Rainforest (Portuguese: Amazonian Rainforest or Amazônia, Spanish: Amazonian Rainforest, Amazonia or usually Amazonia, French: Forêt amazonienne, Dutch: Amazoneregenwoud), also known in English as Amazonia or Amazon Jungle, is a broadleaf rain forest in the Amazon. Biome that covers most of the Amazon basin of South America. This basin covers 7,000,000 km2 (2,700,000 square miles), of which 5,500,000 km2 (2,100,000 square miles) are covered by tropical rainforest. This region includes territory belonging to nine nations. Most of the forest is within Brazil, with 60% of the rain forest, followed by Peru with 13%, Colombia with 10% and with smaller amounts in Venezuela, Ecuador, Bolivia, Guyana, Suriname and French Guiana . States or departments in four nations contain "Amazons" in their names. The Amazon represents more than half of the remaining rainforests on the planet, [1] and comprises the largest and most biodiverse stretch of tropical rainforest in the world, with an estimated 390 billion individual trees divided into 16,000 species

History

natural

The rain forest was probably formed during the Eocene era. It appeared after a global reduction in tropical temperatures when the Atlantic Ocean had widened enough to provide a warm and humid climate to the Amazon basin. The rainforest has existed for at least 55 million years, and most of the region remained free of savanna-type biomes at least until the current ice age, when the climate was drier and the savannah was more widespread. [Four. Five]

After the Cretaceous-Paleogene extinction event, the extinction of the dinosaurs and the more humid climate may have allowed the rainforest to spread throughout the continent. From 66 to 34 Mya, the tropical forest extended south to 45 °. Climatic fluctuations during the last 34 million years have allowed savanna regions to expand to the tropics. During the Oligocene, for example, the tropical forest encompassed a relatively narrow band. It expanded again during the Middle Miocene, and then retreated to a mostly interior formation at the last glacial peak. [6] However, the rainforest still managed to thrive during these glacial periods, allowing the survival and evolution of a wide diversity of species.

During the Middle Eocene, it is believed that the drainage basin of the Amazon was divided along the middle of the continent by the Purus Arch. The water on the east side flowed to the Atlantic, while to the west the water flowed into the Pacific through the Amazon Basin. However, as the mountains of the Andes rose, a large basin enclosing a lake was created; now known as the Solimões Basin. In the last 5-10 million years, this accumulation of water crossed the Purus Arch and joined the flow from the east to the Atlantic.

There is evidence that there have been significant changes in the vegetation of the Amazon rainforest in the last 21,000 years through the last glacial maximum (LGM) and the subsequent deglaciation. Analyzes of the sediment deposits of the Paleolac of the Amazon basin and of the Amazonian range indicate that rainfall in the basin during the LGM was lower than in the present, and this was almost certainly associated with reduced coverage of humid tropical vegetation in the basin.  There is a debate, however, about how extensive this reduction was. Some scientists argue that the rainforest was reduced to small isolated refuges separated by open forests and pastures;  other scientists argue that the rainforest remained largely intact but extended less to the north, south and east than is seen today. 12] This debate has been difficult to resolve because the practical limitations of working in the rainforest mean that data sampling deviates from the center of the Amazon basin, and both explanations are reasonably well supported by the available data.


The dust of the Sahara desert swept by the wind to the Amazon
More than 56% of the dust that fertilizes the Amazon rainforest comes from the Bodélé depression in northern Chad in the Sahara desert. The powder contains phosphorus, important for the growth of plants. The annual dust of the Sahara replaces the equivalent amount of phosphorus that is washed annually in the soil of the Amazon rain and flood.  Up to 50 million tons of Saharan dust are transported per year through the Atlantic Ocean.  NASA video.

NASA's CALIPSO satellite has measured the amount of dust transported by the wind from the Sahara to the Amazon: an average of 182 million