More than a quarter of forests lost worldwide in the last 15 years were permanently destroyed by commercial agriculture, mining and energy infrastructure, and there's no sign that polices are slowing such commodity-driven destruction, according to new research from the Department of Geographical Sciences.

Alongside colleagues from the University of Arkansas-based Sustainability Consortium and the World Resources Institute, the University of Maryland researchers used satellite imagery to classify forest loss and assign a cause of forest loss for each 10 x 10 kilometer parcel of land globally between 2001 and 2015.

Their findings, published today in Science, attribute 27 percent of global forest loss to permanent conversion of the land for the production of commodities such as palm oil and other agricultural products, mining or energy infrastructure. The remainder of the forests were lost to things like shifting cultivation, forestry and wildfire—scenarios in which eventual forest regrowth remains possible. (Urbanization is another form of semi-permanent forest conversion, but it accounted for less than 1 percent of global forest loss.)Map

“It’s important to note that not all forest loss is necessarily permanent,” said Alexandra Tyukavina, a postdoctoral associate with the UMD Department of Geographical Sciences and a co-author on the study. “However, our work reveals the stark reality that more than a quarter of the forests lost in the last 15 years or so represent deforestation—meaning they are not re-growing any time soon.”

Results also indicate that, despite recent commitments from nearly 450 companies worldwide to end deforestation in their supply chains by 2020, the rate of commodity-driven deforestation did not decline between 2001 and 2015.

“Our findings clearly show that policies designed to achieve zero-deforestation commitments are not being adopted or implemented at the pace necessary to meet 2020 goals,” said UMD Professor Matt Hansen, a co-author in the research. “However, we hope our analysis can help international policymakers better understand what is creating changes to forest cover around the world so that we can stop or, at the very least, slow the loss of ecologically important forests in the future.”

The research team is currently working on a more detailed map of forest disturbance drivers to provide better analysis at the national, regional and local levels.