LiveScience.com wrote:
Trees in the Amazon grow slower and are older than scientists thought, a discovery that has implications for computer models of climate change.
Up to half of all trees greater than 4 inches (10 centimeters) in diameter in Amazon tropical forests are more than 300 years old, the study found. Some are 1,000 years old.
"Little was known about the age of tropical trees, because they do not have easily identified annual growth rings," said study team member Susan Trumbore of the University of California at Irvine. "No one had thought these tropical trees could be so old, or that they grow so slowly."
The conclusions result from radiocarbon dating methods. The results were reported last week in the online edition of the Proceedings of the National Academy of Sciences.
The finds have implications for the role the Amazon plays in determining global carbon dioxide levels. Carbon dioxide is a greenhouse gas, acting like a blanket to trap solar energy near the surface.
Trees and other plants soak up carbon dioxide, cleaning the air.
Because the trees are old and slow-growing, the Amazon forests, which contain about a third of all carbon found in land vegetation, have less capacity to absorb atmospheric carbon than previous studies predicted, Trumbore and her colleagues said.
"In the Central Amazon, where we found the slowest growing trees, the rates of carbon uptake are roughly half what is predicted by current global carbon cycle models," Trumbore said. "As a result, those models—which are used by scientists to understand how carbon flows through the Earth system—may be overestimating the forests’ capacity to remove carbon dioxide from the atmosphere."
The oldest known tree is a bristlecone pine in California. At an estimated age of 4,700 years, it is nicknamed Methuselah after a Biblical character purported to have reached the age of 969.
I hope this isn't used as an excuse to increase deforestation of the area.
"If one needed proof that a guitar was more than wood and string, that a song was more than notes and words, and that a man could be more than a name and a few faded pictures, then Robert Johnson’s recordings were all one could ask for."
drachefly wrote:Removing the trees still reintroduces the carbon just as fast as we thought it would... and it won't be taken back as quickly.
Overall, I can see no part of this that is good news.
The point is that the forest has only been absorbing half as much carbon as we thought it was, so that the environmental trends we've been suffering from lately are taking place with a world carbon sink at least 1/6th smaller than we thought it was. That means that our current models are off (since 1/6th of the world's carbon sink not existing is hardly a small matter in terms of simulation) and the current rate of carbon increase is happening in the context of a smaller world sink.
This means that either there is less carbon being released into the atmosphere than was previously thought, or else there is some other carbon sink somewhere else which we don't know about yet.
The threshold for inclusion in Wikipedia is verifiability, not truth. -- Wikipedia's No Original Research policy page.
I hope this isn't used as an excuse to increase deforestation of the area.
Brazilian politics did not even cared about it - in fact there 2 years that I heard this story about the caborn holes being smaller than we thought - and there is no difference at all.
There is simple no political will and too much economic pressure together with a super incapacity of the Brazilian governament to control the area (I know a park with the size of small countries that have just a single person to watch out for it for example) to any study change anything.
Muffin is food. Food is good. I am a Muffin. I am good.
