Some forests store more carbon than previously thought

A new study published in the journal Ecological Solutions and Evidence has found that UK forests could store nearly double the amount of carbon than previous models estimated. These findings have major consequences for our understanding of carbon stocks and could more efficiently guide humanity’s response to climate change.

The scientists used a 3D scanning technique and analysis called “terrestrial laser scanning” (TLS) to assess the amount of aboveground biomass (AGB) – used to derive carbon storage – of 815 trees in a 1.4 ha section of Wytham Woods in Oxfordshire. The analysis revealed that UK woodlands could in fact store 77 percent more carbon than previously thought.

“Forests currently act as a carbon sink in the UK. However, whilst our finding that the carbon storage capacity of typical UK woodland could be nearly double what we previously thought might seem like a purely positive outcome, in practice this means that for every ha of woodland lost, we’re potentially losing almost twice the carbon sink capacity we thought,” said study senior author Mathias Disney, a professor of Remote Sensing at the University College London (UCL). “This has serious implications for our understanding of the benefits of protecting trees in terms of climate mitigation – and deforestation and afforestation targets more broadly.”

These findings bring into question the certainty of previous estimates of forest carbon storage across the UK, especially for the largest and most carbon-heavy trees, which are based on models estimating tree mass from the trunk diameter.

“Currently, most estimates of forest carbon stocks are based on simple allometric models that assume that a tree’s size and mass increase at a steady rate. Our findings show that relying on these models is problematic, as they are not representative of UK forests,” explained study lead author Kim Calders, a professor of Earth Observation and Terrestrial Ecology at Ghent University.

“While the models work well for trees smaller than around 50 cm in diameter, which are fairly uniform in terms of their size and volume, this isn’t what we see for larger, heavier trees. These are far more complex when it comes to structure – and they vary hugely across place and species.”

“It’s vital that we’re able to reduce uncertainty in forest carbon estimates, given that land use, and forest protection and restoration in particular, constitute a quarter of countries’ current commitments to their Paris Agreement targets.”

—

By Andrei Ionescu, Earth.com Staff Writer

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.