By Conrad Duncan, The Independent
Large ecosystems like the Amazon rainforest could collapse in less than 50 years once a crucial tipping point is reached, a new study has claimed.
Researchers have argued some natural environments are collapsing at a “significantly faster rate” than previously thought and could transform into “alternative ecosystems” when put under stress.
The study was based on computer simulations using real-world data from more than 40 natural environments. It suggested that the Amazon could shift to “a savannah-type ecosystem with a mix of trees and grass” in just 49 years. (It might not take that long.)
Meanwhile, the Caribbean coral reefs, which are approximately 20,000 square kilometres in size, could become bleached and sparsely populated in just 15 years.
The researchers studied data on the transformations of four land, 25 marine and 13 freshwater ecosystems to come to their conclusions.
“Unfortunately, what our paper reveals is that humanity needs to prepare for changes far sooner than expected,” said Dr. Simon Willcock, a joint lead author on the study, from the Bangor University School of Natural Sciences.
The research, which included teams from Bangor University, Southampton University and the School of Oriental & African Studies, University of London, used computer modelling to find that while larger ecosystems took longer to collapse, their breakdown occurred relatively quickly compared with smaller systems.
“We intuitively knew that big systems would collapse more slowly than small ones – due to the time it takes for impacts to diffuse across large distances,” said John Dearing, a professor of physical geography at Southampton University.
“But what was unexpected was the finding that big systems collapse much faster than you might expect – even the largest on Earth only taking possibly a few decades.”
James Crabbe, a professor of biochemistry who was not involved in the study, described the research as “thorough and well-researched.”
However, Dr. Erika Berenguer, a senior research associate at the University of Oxford and Lancaster University, who was also not involved in the study, said its conclusions were not supported by the data analyzed.
Dr. Berenguer argued the claim that the Amazon could become a “savannah-type ecosystem” was not tested in the paper, which was published in Nature Communications.
“The authors use data from only four terrestrial systems, none of which is a tropical rainforest, but still claim that the Amazon, the largest rainforest on the planet, will experience a dieback in just 50 years,” she said. “While there is no doubt that the Amazon is at great risk and that a tipping point is likely, such inflated claims do not help either science or policy making.”
In 2019, South America saw a surge in wildfires across the Amazon within Brazil, Bolivia, Paraguay and Peru, leading to international concern about the future of the rainforest.
During the peak of the wildfire season in August, Brazil’s National Institute for Space Research reported more than 80,000 fires across the country – a 77 per cent year-on-year increase.
“It’s pretty clear that if you destroy forests, you will have an entirely different ecosystem–one that supports very little biodiversity,” said Gary Chandler, Director of Sacred Seedlings. “The type of proof that Berengeur calls for puts conservation on hold and promotes the tipping point toward collapse. To argue otherwise is reckless.”
Sacred Seedlings is a global initiative to support forest conservation, reforestation, urban forestry, carbon capture, sustainable agriculture and wildlife conservation. Sustainable land management is critical to the survival of entire ecosystems.