Post by Andrei Tchentchik on Jan 23, 2020 13:23:49 GMT 2
(.#A.021).- Tropical forests, a lung that is running out of steam.
Tropical forests, a lung that is running out of steam.
Monday, August 10, 2019.
Warming limits their ability to absorb CO2.
PARIS - (AFP) Particularly vulnerable to climate change and victims of massive deforestation, forests in the tropics are showing signs of slowing down, raising fears that they may no longer play their full role as carbon sinks, vital to curbing global warming.
Forests, the lungs of the planet with the oceans, absorb between 25 and 30% of greenhouse gases emitted by man, a proportion that is maintained despite the increase in emissions in recent decades. Clearly, without them, climate change would be much worse.
The increase of CO2 in the atmosphere is supposed to stimulate photosynthesis. In principle, good news for the climate: more trees and leaves that in turn absorb more CO2 responsible for warming.
But in tropical forests, which account for about a third of the world's 3,000 billion trees, other factors, from rising temperatures to lack of nutrients, limit photosynthesis, according to a series of studies released this summer.
"For a long time, we talked about tropical forests as carbon sinks: biomass stocks were steadily increasing," says Jean-Pierre Wigneron, from the French National Institute for Agricultural Research. May "today the situation has changed: stocks are stable".
Based on satellite data, the researcher and his colleagues estimated that the aerial plant biomass in the tropics has remained stable since 2010, according to a study published in Nature Plants.
A CONTRIBUTOR
Another Nature Communication publication this week, which also took into account emissions from the ground, goes further: the tropics have become a net CO2 contributor.
"Extensive drought and significant changes in land use in an area with high carbon soils are conditions that could release soil carbon," says lead author Paul Palmer.
F I N.
Tropical forests, a lung that is running out of steam.
Monday, August 10, 2019.
Warming limits their ability to absorb CO2.
PARIS - (AFP) Particularly vulnerable to climate change and victims of massive deforestation, forests in the tropics are showing signs of slowing down, raising fears that they may no longer play their full role as carbon sinks, vital to curbing global warming.
Forests, the lungs of the planet with the oceans, absorb between 25 and 30% of greenhouse gases emitted by man, a proportion that is maintained despite the increase in emissions in recent decades. Clearly, without them, climate change would be much worse.
The increase of CO2 in the atmosphere is supposed to stimulate photosynthesis. In principle, good news for the climate: more trees and leaves that in turn absorb more CO2 responsible for warming.
But in tropical forests, which account for about a third of the world's 3,000 billion trees, other factors, from rising temperatures to lack of nutrients, limit photosynthesis, according to a series of studies released this summer.
"For a long time, we talked about tropical forests as carbon sinks: biomass stocks were steadily increasing," says Jean-Pierre Wigneron, from the French National Institute for Agricultural Research. May "today the situation has changed: stocks are stable".
Based on satellite data, the researcher and his colleagues estimated that the aerial plant biomass in the tropics has remained stable since 2010, according to a study published in Nature Plants.
A CONTRIBUTOR
Another Nature Communication publication this week, which also took into account emissions from the ground, goes further: the tropics have become a net CO2 contributor.
"Extensive drought and significant changes in land use in an area with high carbon soils are conditions that could release soil carbon," says lead author Paul Palmer.
F I N.
