UK trees catch double the carbon

Climate change mitigation is just one of the many environmental benefits provided by trees and woods, but it is a key reason why trees are so vital in the fight against climate change. Here AWA Tree Consultant Lucy Garbutt details new research using laser scanning of woodlands to reveal potential significant underestimations of biomass carbon in our temperate forests:

Trees and forests can help limit rising levels of carbon dioxide in the atmosphere. Trees capture and sequester carbon, ‘locking in’ lots of the carbon emissions that human activities release, preventing it from being trapped in the atmosphere and causing global warming.

It has recently been uncovered that UK trees could actually sequester twice as much carbon as previously thought.

Previously, the only way to calculate carbon content of trees was to cut the trees down and weigh their trunks and branches (which of course is detrimental to the trees!), so most carbon calculations were estimates performed based on physical measurements. As of 2022, new advances in technology, including 3D scanning techniques and lasers, meant that research scientists were able to scan trees in Wytham Wood, Oxfordshire, and use this new technology to create maps of each tree and convert these into a model that could then be used to calculate their carbon storage.

The models demonstrate that many of the older trees in the wood could potentially have been historically underestimated in the amount of carbon they are able to store. It is suggested that much of the discrepancy may have come from heavy reliance on smaller trees when the original models were constructed. The original allometric models used to calculate the ‘weight’ of trees were based on trees measured in the lake district in the 60’s, which were typically smaller in stem diameter than those that are found in Wytham Woods. In fact much of the trees in Wytham Woods have a larger stem diameter than the typical ‘cut off’ diameter used in the previous allometric models. These larger and older trees make up the majority of the biomass within the forest, but therefore were not included to their full extent in historical models used for estimating carbon. The new models, which arise from the latest advances in technology, mean that older and larger trees in the UK may be even more vital to the battle against climate change than previously thought.

Wytham Wood is a typical example of UK deciduous woodland, and is one of the most scientifically studied forests in the world, meaning the results from these new models are extendible and could afford accurate estimates for the carbon storage potential of forests across the UK. Scientific researchers argue that the value of forests in the UK as carbon sinks is ‘’incalculable’’ and that whilst these measurements bring positive news for those forests remaining in the UK, for those that have already been cut down it suggests that twice the carbon we thought was released from this destruction may have actually been released.

This research has implications for tree replacement policies, which should account for the differences between trees age, as well as other factors like species and condition, in carbon sequestration potential.

To read more about this topic, see the original article here: