You may have heard the tired argument that if carbon dioxide levels are going up, it’s going to be great for boosting the growth of trees. It’s true – to an extent. But there’s a really important detail we must not miss.

Plants, including trees, are growing faster thanks to what is known as the carbon fertilisation effect, but past studies have already suggested that this phenomenon may only be temporary.

A new study has now revealed the potential limits of carbon fertilisation – specifically whether plants are likely to reach a tipping point: when we can no longer expect increasing CO2 to mean increasing plant growth.

“A large part of that gain has been because of carbon dioxide fertilisation (carbon dioxide as plant food). Will this extra growth continue?”

The researchers looked at 138 past experiments which focussed on elevating carbon dioxide levels in a small area – everything from grassland, shrubland, and cropland to forest systems.  […]