A recent study published in nature communications highlights the Amazon Rainforest, among other extremely important ecosystems on Earth, that could collapse much faster than previous estimates.
The study was led by Professor John Dearing from the University of Southampton, who said:
The messages here are stark. We need to prepare for changes in our planet’s ecosystems that are faster than we previously envisaged.
Even though the Amazon was their main example, they used a total of twelve ecological modeling experiments to try and determine what happens when a region reaches a “tipping point.” They chose some models to include reversible non-catastrophic shifts and ones that would cause catastrophic scenarios.
They looked at anthropogenic activities that are dependent on the persistence of various biophysical conditions. These included soil fertility, stable fish populations, and freshwater availability. The “tipping points” were explained as often unexpected changes in relatively stable ecosystems, causing the rapid breaking down of a once stable system.
The paper warns that the larger an ecosystem is the faster and harder it will fall. For one the size of the Amazon, which has been around for 55 million years, a collapse could happen as quickly as 50 years. The coral reefs in the Caribbean may collapse as quickly as 15 years once it is triggered.
Dearing explains further on the team’s findings:
What is new is that we are showing this is part of a wider story. The larger the system, the greater the fragility and the proportionately quicker collapses. What we are saying is don’t be taken in by the longevity of these systems just because they may have been around for thousands, if not millions, of years – they will collapse much more rapidly than we think.
This speaks to the importance of a recent decision by U.S. District Court Judge Sharon Gleason to protect the Tongass National Forest in Alaska from the Trump administration and loggers who were preparing to cut down hundreds of thousands of acres of old-growth national forest. The effects it would have on the entire forest system would be irreversible in our lifetime.
Ima Viera is an ecologist from the Museu Emílio Goeldi in Belém, Brazil, she was not involved in the study, however, she did comment on the results as reported in the Guardian:
This is a very important paper. For Brazil to avoid the ecosystem collapse modeled in this study, we need to strengthen governance associated to imposing heavy fines on companies with dirty supply chains, divestment strategies targeting key violators and enforcement of existing laws related to environmental crimes. And we have to be quick.
The researchers studied 42 previous cases and studied the ecosystem size and the rate at which they collapsed. From the bleaching of the coral reefs in Jamaica, death of vegetation in the Sahel, to the collapse of fisheries in Newfoundland. The point of this study was an overview of just how quickly these collapses can occur, and the destruction being done to the Amazon, is a major cause for concern.
The paper concludes by saying:
We must prepare for regime shifts in any natural system to occur over the ‘human’ timescales of years and decades, rather than multigenerational timescales of centuries and millennia. Humanity now needs to prepare for changes in ecosystems that are faster than we previously envisaged through our traditional linear view of the world, including across Earth’s largest and most iconic ecosystems, and the social-ecological systems that they support.
