In a recent study Crowther, et. al. finds that scientists underestimate the number of trees on earth and that the new estimate, obtained using ground-based sensors rather than satellite imagery, is exceedingly higher than previously thought. Using over 400,000 ground-based measurements of tree density from every continent on Earth except Antarctica, the researchers estimate that there are approximately 3.04 trillion trees across the planet. This number is an order of magnitude higher than the previous global estimate of 400 billion trees. With a worldwide human population of 7.2 billion, the ratio of trees per person increases from 61:1 to 422:1.
The new measurement provides scientists with the opportunity to more accurately evaluate the effect of mankind on tree numbers. The data shows that as humans contend directly with forest ecosystems for available space, trees are often relegated to drier regions while moist, productive land is preferentially used for agriculture and infrastructure. They estimate that the global number of trees has declined 46% since the beginning of human civilization and that an astounding 15 billion trees are lost each year as a result of deforestation and land use.
Accurate measurement of regional and global tree density provides a baseline for establishing goals for the protection of trees and for targeted reforestation efforts. Public and private-sector decision makers are now armed with a more accurate picture of tree density on a global scale and it is hoped that this new information will help guide forest management practices that safeguards trees.
At Sapwood we champion sustainability efforts that preserve our valued forest ecosystems. Our goal is to inspire a sense of adventure and create an opportunity to connect with nature in everyday life, while also engaging society in a positive way that gives everyone the change to give back. Every purchase of a Sapwood Air Freshener plants a tree in a developing country. Will you join us as we try to make the world a better place, one tree at a time.
Reference: Crowther, T.W., et. al. Mapping tree density at a global scale. 2015. Nature 525: 201.