Forests the size of France have regenerated over past 20 years

Study highlights forests’ capacity to regenerate themselves and will guide reforestation projects to help tackle climate crisis, researchers say

An area roughly the size of the Netherlands has regrown in Brazil’s Atlantic Forest since 2000 (Getty)

Over the past two decades, 59 million hectares of forest – an area equivalent to the size of France – have regenerated around the world with minimal human intervention, a new study shows.

Major hotspots where woodlands have recovered include parts of Brazil’s Atlantic Forest, areas of northern Canada, central Africa and the boreal forests in Mongolia’s northern wilderness.

This area of forest has the potential to store the equivalent of 5.9 gigatonnes of carbon dioxide – more than the annual emissions of the US.

The authors said forest regeneration is where “nature takes the lead”. Some areas require no human activity to help them regenerate, while others require invasive species or farm animals to be removed or fenced out of the area.

The research, which was based on satellite imaging and ground surveys, comes amid a growing awareness of the importance of tree cover in efforts to mitigate the worst impacts of the climate crisis.

The analysis was carried out by Trillion Trees, a joint venture between BirdLife International, the Wildlife Conservation Society and the WWF, which is aiming to “urgently speed up and scale up” forest regeneration, and is aiming to protect and restore one trillion trees by 2050.

As well as specific regeneration areas, the study’s authors said other reasons for forest expansion included more responsible industry practices and factors such as human migration towards cities.

The WWF’s William Baldwin-Cantello said allowing woodlands to naturally regenerate is often more effective than human efforts to bring back trees.

He said: “The science is clear: if we are to avoid dangerous climate change and turn around the loss of nature, we must both halt deforestation and restore natural forests.

“We’ve known for a long time that natural forest regeneration is often cheaper, richer in carbon and better for biodiversity than actively planted forests, and this research tells us where and why regeneration is happening, and how we can recreate those conditions elsewhere.”

But he warned that despite the good news the study highlighted, the rate of deforestation is still far outpacing that of regrowth, and called on the government to take action on supply lines which result in deforestation around the world.

He said: “We can’t take this regeneration for granted – deforestation still claims millions of hectares every year, vastly more than is regenerated.

“To realise the potential of forests as a climate solution, we need support for regeneration in climate delivery plans and must tackle the drivers of deforestation, which in the UK means strong domestic laws to prevent our food causing deforestation overseas.”

The researchers highlighted the Atlantic Forest in Brazil as one particular area which was seeing considerable regeneration. An estimated 4.2 million hectares – an area roughly the size of the Netherlands – has regrown since 2000.

In the boreal forests of Mongolia’s northern wilderness, the study suggests around 1.2 million hectares of forest have regenerated in the last 20 years. The study said this progress was partly due to the work of the WWF, as well as increased emphasis from the Mongolian government on protected areas.

The WWF warned that despite apparent momentum behind woodland restoration, in many cases, government plans “involve very limited expansion of natural forests, despite the strong climate and biodiversity benefits they offer”.

The authors of the study warn that encouraging signs of regeneration cannot be taken for granted. Forests across Brazil face significant threats today, even the Atlantic Forests – a recognised success story in restoration. Such is the extent of historic deforestation that the area of this unique forest still needs to more than double from currently 12 per cent of its original area to 30 per cent, in order to reach what scientists believe is a minimal threshold for its lasting conservation.

Naikoa Aguilar-Amuchastegui, senior director of forest carbon science at WWF, and who led the data analysis team said: “Even though this is an exploratory effort, it still highlights the potential that enabling and consolidating regeneration has for mitigating climate change and securing its biodiversity benefits. However, this remains difficult to map and a lot of additional work lies ahead.”

Trillion Trees said it is now planning to invite local groups and green funding organisations to work on new landscape restoration ventures, focusing on areas offering the maximum benefit for vulnerable ecosystems and local communities.