By Carlos A. Moreno |
Rio de Janeiro (EFE).- The mangroves on the Brazilian Amazon coast are not only the largest in the world, with an area of 7,820 square kilometers, but also the best preserved, which guarantees their important role in maintaining the region’s biodiversity and in combating climate change.
The high degree of preservation of Amazonian mangroves was confirmed by a study carried out by researchers from the Vale Technological Institute (ITV) and published this Friday in the journal “Annals of the Brazilian Academy of Science”.
According to the study, which used satellite images captured between 2011 and 2015 and compared them with those that existed years before, 92% of the area of Amazonian mangroves is still covered by forests, 7% by salt flats common in mangrove areas, and only 1% was affected by road construction or urban expansion.
His natural exuberance
The areas most affected by human activity are the salt flats, which in a small part have been adapted for the breeding of shrimp, crabs and other marine species.
The greatest degradation was caused by the construction in the 1970s and 1980s of the PA-458 regional highway, which cut through the mangrove swamp for 26 kilometers.
“Those of the Brazilian Amazon are the largest mangroves in the world and the best preserved thanks precisely to their natural exuberance, since their flooded plains and slime deposits are up to 40 kilometers wide and trees up to 30 meters high,” biologist Pedro Walfir Souza Filho, ITV researcher and lead author of the study, told EFE.
The specialist also attributed the preservation to the absence of large cities in its vicinity, the low population density, the difficulties of access and the lack of infrastructure such as electricity transmission lines.
“It is also important to highlight that various conservation units have been created in the last 20 years along the coast with the intention of avoiding the degradation of this important ecosystem,” explained Souza Filho, who estimates that environmental reserves protect about 80% of the area.
The Amazon is home to 80% of Brazil’s mangroves
This coastal biome in the Amazon corresponds to about 80% of all the mangroves in Brazil and extends along 678 kilometers of the northern coast of Brazil over the Atlantic and south of the mouth of the Amazon.
Souza Filho rules out that the possibility that Brazil approves the exploitation of oil in the promising reserves of the so-called Equatorial Margin, in very deep waters of the Atlantic and in front of the mouth of the Amazon, threatens the mangroves.
“The exploration areas are in deep sea in an area with a strong action of the North Oceanic Current of Brazil, which flows at speeds greater than one meter per second in a northwesterly direction. That way, in the event of a possible spill, the spilled crude will not head south,” he said.
“In my opinion, the daily transport of fuels through the rivers of the Amazon represents a much higher risk of contamination than the exploitation of oil deposits more than 150 kilometers from the coast and at depths of more than 2,000 meters,” he added.
Its conservation is essential
The specialist considers that one of the main threats to the ecosystem is global warming because the rise in sea level has caused mangroves to migrate upstream due to the salinization of river channels.
He affirmed that it is a threat to an important ecosystem to help combat climate change itself, because studies have shown that mangroves have a capacity to capture carbon dioxide twice that of the Amazon rainforest itself.
“Their conservation is essential so that these sequestered gases are not released into the atmosphere,” he said.
He also highlighted the important role of mangroves in conserving biodiversity, since they are the cradle of various species and a source of food for many others.
The region is habitat for numerous species of birds, especially herons and scarlet ibis, and mammals such as crab-eating raccoons, anteaters, and corn monkeys.