What future impacts will drought have on the Amazon rainforest due to climate change? This is something that a team of approximately 80 researchers from South America and Europe hope to figure out in a recent study published in Nature where they examine how drier conditions in the Amazon rainforest could lead to dying trees in the future.
Image from a Peru forest canopy. (Credit: Francisco Diniz)
For the study, the researchers not only examined future impacts of climate change on the Amazon, most notably drier conditions due to increased temperatures, but also investigated previous estimates regarding drought impact in the Amazon, as well.
“The Amazon is threatened by multiple stressors, including deforestation and climate,” said Dr. David Galbraith, who is an Associate Professor in Earth System Dynamics at the University of Leeds, and a co-author on the study. “Understanding the stress limits that these forests can withstand is a major scientific challenge. Our study provides new insights into the limits of forest resistance to one major stressor - drought.”
The study’s findings not only indicated an increased risk of death among trees in the southern and western Amazon, but they also emphasize that previous studies underestimate the impact of drought on the Amazon since those studies primarily focused on the central-eastern areas of the Amazon.
It was also found that the southern Amazon has been particularly hit hard by drought, which is noted by longer dry seasons from decreased rainfall and increased temperatures. It is currently hypothesized that these drastic environmental changes have come from the vast deforestation taking place there. While trees in the southern Amazon were shown to have adapted to the decreased rainfall and increased drought, the researchers still stress these trees face the greatest risk of dying in the future due to the current environmental conditions.
Study co-author, Dr Julia Tavares. (Credit: Francisco Diniz)
“A lot of people think of the Amazon as one large forest,” said Dr. Julia Tavares, who is a postdoctoral researcher at Uppsala University but conducted the research while a PhD student at Leeds and is a co-author on the study. “But it is not. It is made up of numerous forest regions that span different climate zones, from locations that are already very dry to those that are extremely wet, and we wanted to see how these different forest ecosystems are coping so we could begin to identify regions that are at particular risk of drought and drier conditions.”
Selfie from tree climber, Martin Acosta. (Credit: Martin Acosta)
According to the study, between 10 to 15 percent of the world's vegetation-stored carbon is housed in the Amazon Forest, which indicates the Amazon Forest plays a vital part in naturally sequestering carbon from the atmosphere. This would be substantially decreased if the plant drought increases tree deaths, according to the study's models.
In conclusion, the researchers stress that current models of the Amazon Forest's future should be re-examined and updated based on their findings.
What new discoveries will scientists make about how climate change is impacting the Amazon rainforest in the coming years and decades? Only time will tell, and this is why we science!
Sources: Nature, EurekAlert!
As always, keep doing science & keep looking up!
