2 October 2015 14:55

The number of trees on the planet is around 3.04 trillion – a much larger number than previously thought, according to researchers publishing in Nature.

Previous satellite-imagery based estimates of global tree numbers stood at around 400.25 billion, meaning for every person on the planet there were around 61 trees. This number had, however, been thrown into doubt by a recent study suggesting there were around 390 billion trees in the Amazon basin alone.

The new research paper ‘Mapping tree density at a global scale’ draws upon 429,775 ground-sourced measurements of tree density from every continent on Earth except Antarctica to generate a new global map of forest trees.

The new map reveals a more nuanced and accurate picture of forest ecosystems around the world and it seems there are far more individual trees in our forests than previously thought.

The international team, which included Lancaster University, also estimated global number of trees had fallen by approximately 46% since the start of human civilization with around 15 billion trees being cut down each year.

Writing in the report the researchers said: “Forest ecosystems harbour a large proportion of global biodiversity, contribute extensively to biogeochemical cycles, and provide countless ecosystem services, including water quality control, timber stocks and carbon sequestration.

“Our current understanding of the global forest extent has been generated using remote sensing approaches that provide spatially explicit values relating to forest area and canopy cover. Used in a wide variety of global models, these maps have enhanced our understanding of the Earth system but they do not currently address population numbers, densities or timber stocks.”