Study calls for tree planting to tackle climate crisis
Trees store carbon dioxide with the research estimating that a global programme could remove two-thirds of all the emissions.
Urban trees both cool city streets and reduce air pollution. They can also boost wellbeing, with research showing two-hour “dose” of nature a week significantly improves health.
The analysis found there are 1.7 billion hectares of treeless land on which 1.2 trillion native tree saplings would naturally grow.
The researchers identified six countries where most of the reforestation could occur: Russia (151 million hectares), US (103 million), Canada (78 million), Australia (58 million), Brazil (50 million) and China (40 million).
Using Google Earth, the scientists were able to develop a predictive model to design the global potential for tree cover.
There are about 3 trillion trees on the planet, about half as many as existed before the start of human civilisation.
The area is about 11 per cent of all land and equivalent to the combined size of the US and China. Tropical areas could have 100 per cent tree cover, while others would be more sparsely covered, meaning about half the area would see tree coverage.
Today, an estimated 10 billion more trees are cut down than are planted each year.
The scientists included grazing land, on which the researchers said scattered trees could benefit livestock.
Forests are a rich habitat for wildlife with the Earth starting a sixth mass extinction of species and the razing of forests and other ecosystems is the biggest contributor.
Tropical rainforests host half of the known terrestrial species on only 6 per cent of the land. Trees also help control regional rainfall, as they evaporate water from their leaves.
“This new quantitative evaluation shows [forest] restoration isn’t just one of our climate change solutions, it is overwhelmingly the top one,” said Professor Tom Crowther at ETH Zurich university. “What blows my mind is the scale. I thought restoration would be in the top 10, but it is overwhelmingly more powerful than all of the other climate change solutions proposed.”
Tree planting was “a climate change solution that doesn’t require President Trump to immediately start believing in climate change, or scientists to come up with technological solutions to draw carbon dioxide out of the atmosphere”, Crowther said. “It is available now, it is the cheapest one possible and every one of us can get involved.”
Crown shyness stops the spread of disease. Picture credit: Wikimedia