Rainforests are Recovering Faster Than Expected

As the work to restore the damage to natural ecosystems gains steam, people are discovering that nature itself also fights back. Given the chance, a rainforest, one of the planet’s most important ecosystems, can mostly restore itself within a human generation. This is very encouraging news.

A new study published in Nature, showed that rainforests can restore themselves nearly completely in thirty years, even after they have undergone intense damage. The forest is not as fragile as it seems. 

Ecuadorian Recovery
In order to test rainforest recovery, the researchers set their sites on the Chocó region of Ecuador, according to Earth.com. This region is home to untouched rainforests as well as plots of land that had been cleared for agriculture use, and are now abandoned. This was the perfect mix to study how a rainforest regenerates itself. 

The study focused on 62 different areas, and followed the fates of 10,000 different types of living things from soil bacteria, to animals, and plant life. What they discovered was that the forest was a lot more resilient than they had thought. 

“Rainforests, as complex ecosystems and species-rich communities, demonstrate remarkable resilience and the ability to return to their original state,” the study’s lead author Dr. Timo Metz told Earth.com. 

Resistance and Return Rate
Mongabay reports that secondary forests — that is to say forests that regrow in areas that had been previously cleared — are able to recover in terms of abundance and species diversity within a few decades. Full recovery, which is when the recovered forest resembles the composition of an undisturbed forest, can take many more decades.

The study focused on two components of recovery — resistance and return rate. Resistance measures how much a living community persists during disturbance. Return rate refers to how quickly a species recovers after. These two measures do not necessarily go together. Some species persist doggedly during a disturbance, but once gone, take a long time to return. While other species disappear fairly quickly but also return fairly quickly. 

An exception to this phenomenon is mobile animals such as birds, bats, and insects. They have both a high resistance and return rate. They also have an outsized effect on their environment by dispersing seeds and pollinating plants. Once the vegetation returns, thanks to these animals, other species can begin returning as well. 

Soil bacteria, on the other hand, though it shows high resistance, takes quite a long time to recover, as do leaf-litter arthropods, and of course, long-lived trees. In addition, the ways the land had been used prior to regrowth is also a factor. Land that had been used to grow cacao, for instance, tends to recover more quickly than land that had been used for pasture. This is because cacao plantations retain more resources and structure than open pasture. 

The study in Nature gives a jolt of hope that the devastation of the rainforests in previous generations can be rectified in less time than expected. On the other hand, it is important to note that new growth cannot truly replace old-growth forests for many many years, and it is incumbent upon humanity to preserve those forests for as long as possible.