Transition

In the name of climate #13: the importance of grasslands for the climate

22/10/2021 2 minutes

We try, every month, to dispel some widespread beliefs about the environment, climate change and ecological transition. In this edition: grasslands absorb carbon dioxide like forests, but emit less in the event of fires.

Forests absorb large amounts of carbon dioxide from the atmosphere and store it as organic matter, mainly in tree trunks, but a recent study published in the British journal Nature Reviews Earth & Environment highlights that grasslands also play a part in this cycle and to help combat the climate crisis it would be in our best interest to preserve them.

Grasslands, ecosystems with low growing plants or various types of grasses, with few trees and shrubs, occupy about 40% of the world’s land area but according to some estimates they have been gradually reduced due to human activity: for example only 4% of grassland in North America has remained unchanged, and even the surface of the Cerrado in Brazil has been more than halved in the last fifty years, with major consequences for both the flora and fauna that inhabit them.

It is estimated that about a third of the carbon present on the planet is stored in the grasslands, and it is retained more effectively than by trees. In the event of a fire, in fact, the carbon stored in the trees is released in the form of carbon dioxide, while that present in the grasslands, being stored underground, is not actually dispersed.

8263 — Grasslands absorb carbon dioxide like forests, but emit less in the event of fires, which is why they are important for the climate (Brett Sayles/Pexels.com)

Furthermore, forests take many years to regrow after a fire, while the vegetation in grasslands regenerates much faster, in fact fires foster regrowth.

The initiatives to plant new trees or safeguard existing forests, with the idea that they can contribute to reducing the amount of carbon dioxide in the atmosphere, should be accompanied - according to the authors of the Nature Reviews Earth & Environment study - by projects to preserve even, and especially, the grasslands.

Richard Bardgett, Professor of Ecology at the University of Manchester, said in this regard that protecting grasslands that are still intact and restoring part of those degraded by human activities should be a priority aspect of international plans for sustainable development. The fact remains that these initiatives alone do not make it possible to completely combat climate change, although they can make an important contribution: the most important strategy, capable of making a difference in this crisis, continues to be reducing the use of fossil fuels.