We need to count every tree on the planet - here’s why

By Jingjing Liang.

Since the 13th century, forests have been managed as sources of trees that can be processed into timber. They are often studied as potential carbon sinks because of their ability to sequester greenhouse gas emissions. The relationship between a forest and trees is largely unknown. There is a lack of knowledge about forests that makes it difficult to make effective decisions.

The Million Tree Initiative, the Plant a Billion Trees scheme and the Trillion Tree Campaign have emerged as highly publicised strategies to increase the number of trees. 10 million hectares of forests worldwide are degraded each year.

Many of the trees we are losing are in primary forests, which are a type of pristine environment that offers a number of benefits, such as harbouring threatened flora and fauna, as well as underpinning the unique cultures and customs of Indigenous communities. Some have survived earthquakes, hurricanes, fires and other natural disasters over thousands of years, but have been wiped off the face of the Earth due to adverse human impacts. We can plant millions, billions or even trillions of trees, but they can't replace the forests we are losing, and very few of these trees will ever grow into a primary forest.

When a forest is seen as a collection of trees, we don't see the full value of its diversity. They are the most important repository of species in the world. When a forest is cut down, we lose other living organisms which can be used to make new materials, processes, designs and inspiration to confront environmental, medical and engineering challenges in a world full of crises. Scientists discovered a new antibiotic in a Mexican tropical forest, and hundreds of other potential pharmaceuticals are still waiting to be found.

We compiled a ground-sourced forest database to address the lack of knowledge about tree populations. It is a snapshot of the forest environment and allows us to estimate important attributes of forest biodiversity at a global level. The total number of tree species is an attribute. More than 12 percent of the 73,000 tree species on Earth haven't been documented yet, according to our estimate. These findings remind us how little we know about our planet.

The number of tree species at a local level and how evenly trees are distributed are unknown. It's important to map them across the global forest range for a number of reasons.

More than 90 percent of the most diverse forests are in low-income nations, so international communities must work together to protect them. We can begin to see the forest for the trees together.

The Global Forest Biodiversity Initiative is co-founded by Jingjing.