At the University of Birmingham in the UK and Bergen, Norway, scientists have shown that atmospheric carbon dioxide pumped into a mature forest at levels predicted to be the norm by 2050 will cause trees to produce more and longer roots, thus absorbing and storing more carbon. Researcher Angeliki Kourmouli says, “We usually take soil for granted, but it forms a crucial part of many ecosystems and plays a significant role in carbon storage.”

The study team gathered thousands of images of tiny tree roots assembled over two years at the Birmingham Institute of Forest Research Free-Air CO2 Enrichment. The images were used to build a mathematical picture of the birth, growth and death of roots in an oak forest. Some images were taken of roots in situ using a high-resolution camera sent under the forest floor in a set of transparent tubes, and others came from soil cores.

Professor Iain Johnston, who led the study, says, “It’s obviously hard to view these processes going on beneath the ground. But a combination of innovative engineering and careful field and lab work from our team have helped us shed new light on this behavior and on how confident we can be in our findings.”