That’s more than previous estimates. But the number of trees has dropped by 46% since the start of human civilization, says the study.

https://www.youtube.com/watch?v=jqdOkXQngw8


A study by an international team of researchers says that there are 3.04 trillion trees on Earth, roughly 422 trees per person. That number is about 7 times greater than previous estimates.

But according to the study, published in the journal Nature on September 2, the number of trees has dropped by 46% almost half since the onset of agriculture about 12,000 years ago.



Trees] store huge amounts of carbon, are essential for the cycling of nutrients, for water and air quality, and for countless human services. Yet you ask people to estimate, within an order of magnitude, how many trees there are and they don’t know where to begin. I don’t know what I would have guessed, but I was certainly surprised to find that we were talking about trillions.



Using a combination of satellite imagery, forest inventories, and supercomputer technologies, the researchers were able to produce a global map of tree density at the square-kilometer pixel scale. Image credit: Image courtesy of Yale School of Forestry & Environmental Studies
The team used a combination of satellite imagery, forest inventories, and supercomputer technologies to map tree populations worldwide at the square-kilometer level.

The highest densities of trees were found in the boreal forests in the sub-arctic regions of Russia, Scandinavia, and North America. But the largest forest areas, by far, are in the tropics, which are home to about 43% of the world’s trees. (Only 24% are in the dense boreal regions, while another 22% exist in temperate zones.)

Around 15 billion trees are cut down each year, the researchers estimate.
In fact, human activity is the largest driver of tree numbers worldwide, said Crowther. He said:

The scale of human impact is astonishing.Obviously we expected humans would have a prominent role, but I didn’t expect that it would come out as the as the strongest control on tree density.

The researchers found that climate can help predict tree density in most biomes. In wetter areas, for instance, more trees are able to grow. However, the positive effects of moisture were reversed in some regions because humans typically prefer the moist, productive areas for agriculture.

While the negative impact of human activity on natural ecosystems is clearly visible in small areas, the study provides a new measure of the scale of anthropogenic effects, highlighting how historical land use decisions have shaped natural ecosystems on a global scale. In short, tree densities usually plummet as the human population increases. Deforestation, land-use change, and forest management are responsible for a gross loss of over 15 billion trees each year. Crowther said:

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. This study highlights how much more effort is needed if we are to restore healthy forests worldwide.

The study was inspired by a request by Plant for the Planet, a global youth initiative that leads the United Nations Environment Programme’s “Billion Tree Campaign.” Two years ago the group approached Crowther asking for baseline estimates of tree numbers at regional and global scales so they could better evaluate the contribution of their efforts and set targets for future tree-planting initiatives.

At the time, the only global estimate was just over 400 billion trees worldwide, or about 61 trees for every person on Earth. That prediction was generated using satellite imagery and estimates of forest area, but did not incorporate any information from the ground.



Bottom line: A study published Nature on September 2, 2015 says that there are 3.04 trillion trees on Earth, about 7 times greater than previous estimates. According to the study, the number of trees has dropped by 46% almost half since the onset of agriculture about 12,000 years ago.



http://earthsky.org/earth/earth-has-3-trillion-trees-says-study?utm_content=buffer286e1&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

We need more!!


#stay green

johnydon22:
We need much more because we are growing in number. Our oxygen depends on these green friends and so we should try as much as possible to preserve them.

Cut down a tree, replace it by planting another because both plants and animals depend on each other to survive.

If the plants die off, we die....

#StayGreen

The funny part of it is that the study estimated that 1 person is to 400 trees. The rate at which human population is increasing and deforestation is at high rate thus endangering our existence here.

OP I would've guessed quadrillion or more sef , I mean have you been to a forest before? I'm honestly surprised they are in trillions.

I agree with you johnydon22, green should be the new cool but I doubt that's achievable, people never build houses to rent finish and you are talking of planting trees.

na you count am?
just read what happen to a fan that brought a Drake Sign to a Meek mills concept
http://sweetnoisenaija.com/dont-bring-a-drake-sign-to-a-meek-mill-concert/

freecocoa:
OP I would've guessed quadrillion or more sef , I mean have you been to a forest before? I'm honestly surprised they are in trillions.

I agree with you johnydon22, green should be the new cool but I doubt that's achievable, people never build houses to rent finish and you are talking of planting trees.

The methodology they applied to conducted the study is there. I may not have been to any forest but it has nothing to do with the research. have you been to any? especially government reserved ones?