I have good news and not-so-good news. The not-so-good news is that recent research has found that the number of trees on Earth has fallen 46% since human showed up on the scene. The good news is that the research has also provided, with 95% accuracy, that there are still 3.04 trillion trees in the world! That’s 8 times more than previously thought.
The research, conducted by a group of international researchers lead by Yale University, has been published in the journal Nature. Researches used a combination of over 400,000 ground measurements and satellite images to perform the tree count. For their research, they defined a tree as, “a plant with woody stems larger than 10 centimeters [four inches] diameter at breast height.”
In previous studies, researchers only counted plants larger than 50 centimeters (20 inches) in diameter. This new research will also help show how water is being recycled, how much carbon dioxide the atmosphere is absorbing and map endangered species. But, of most significance is just how much humans are impacting our environment. As lead author, Thomas Crowther, notes:
“We’ve nearly halved the number of trees on the planet, and we’ve seen the impacts on climate and human health as a result,” Crowther said in a statement. “This study highlights how much more effort is needed if we are to restore healthy forests worldwide.”
The research’s data will be of great use in discovering how much carbon dioxide is being stored in the Earth’s vegetation. As Crowther told IFLScience, “In the study, we show that there is a positive relationship between the amount of trees in an area and the amount of carbon storage. This relationship was not strong because the highest densities of trees are often dominated by a large number of small trees that don’t store much carbon.”
The research found that .74 trillion trees can be found in boreal regions and .61 trillion in temperate regions, while 1.39 trillion trees live in subtopical and tropical forests. Researches came to these figures on tree density throughout the Earth based on ground data.
One important finding of the study is that much more effort is needed to manage the Earth’s environment. While the UN’s Billion Trees Campaign is a start, planting one billion trees is only 1/3000th of Earth’s tree population.
Another important finding is that, over the last 12 years, there was a gross loss of over 15 billion trees per year. When re-growth is taken into consideration, there is a net loss of 10 billion trees per year. According to Crowther, humans, “are one of the dominant regulators of trees. The one consistent factor is the negative impact of humans.”
The research has made clear that humanity is having a disastrous impact on our environment. Right now there are 422 trees per person on Earth. If things continue as they are now, that number will fall to 214 trees per person in 150 years.
We cannot continue acting as though the Earth will always be as it is now. We have to change the way we are negatively impacting our environment!