The vicious circle drought-deforestation-drought

There are plenty of ridiculous arguments out there from the climate change sceptical Brigade.
The silliest one is that it makes no difference to our planet Earth if we cut more trees or if we increase our carbon dioxide emissions.
The idea here is that carbon dioxide is good for trees and plants, because they feed on it [carbon dioxide].
Therefore, if fewer trees and plants absorb more carbon monoxide, these trees and plants will grow healthier.
Of course, according to them, environmental concerns should never obstruct economic development.

Thank God, these people are not scientists!

However, the real scientists after a long research (spanning about two decades), predictably reached a completely different conclusion, which was published in Nature on 18 March.
According to a team of about one hundred scientists, in the 1990s the Amazon has removed from the atmosphere about 2 billion tons of CO2 each year.
This rate has fallen by a third in the 2000s and today rarely exceed one billion tonnes of CO2.
In those two decades, the efficiency of “carbon sinks” in the Amazon has halved, which means that the Amazon forest absorbs less and less man-made carbon dioxide (CO2).
Therefore, the first bad news is that there is a limit to the capacity of the Amazon forest to absorb carbon dioxide -without mentioning all the other toxic gases released into the atmosphere!

The second bad news is a consequence of the first: excess carbon dioxide is actually killing trees and plants.
Indeed, those scientists observed that during the period of 30 years that they have observed the Amazon rainforest, the mortality rate of vegetation increased by 30%.
Damien Bonal, a researcher at the Biology Laboratory and Forest Ecophysiology of Institut National de la Recherche Agronomique (National Institute for Agricultural Research) and co-author of the study, believes that the exceptional drought that occurred in 2005 and 2010 also had a influence this increased mortality rate.

Lars Hedin (Princeton University, USA) believes that, in all probability, the limited availability availability of water and nutrients, as wel as “heat stress”, do play a role.
A similar conclusion was reached by Dr. Geraldo Wilson Fernandez, researcher at the Institute of Biological Sciences (ICB) at the Federal University of Minas Gerais (UFMG).
Leading expert on the subject, Dr Fernandez goes even further than the first survey.
He was the first in the country to demonstrate that stressed environments by excessive heat, lack of water and lack of nutrients and minerals cause tumors in plants, similar to those that develop in humans!
So it seems that Brazil (and, or that matter, other areas covered by tropical forests, such as Africa and Indonesia) are in the middle of a very nasty vicious circle.
Deforestation along with the excess carbon dioxide, environmental stress, lack of water and lack of nutrients and minerals contributes to the destruction of tropical forests.
But trees are ‘finishing touch’ biological machine that produces rain.
The Amazon pumps into the atmosphere moisture that will turn into rain in the Midwest, Southeast and South of Brazil.
The higher deforestation, less moisture and therefore less rain.
And without rain, the reservoirs are empty and taps dry.

Sources: Nature, Globo, Em, Lemonde

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