Planting trees in vast schemes to ‘offset’ carbon emissions is harming nature, an Oxford study has claimed.
Celebrities and tycoons including Prince Harry and Meghan Markle, Elton John, Emma Watson and Amazon founder Jeff Bezos have all said they have used offsetting to cancel out the greenhouse gases emitted by activities such as flying in private jets.
But when offsetting involves planting large numbers of a single types of tree, it can actually degrade the environment, the authors argued.
Single species plantations are harmful to biodiversity and put forests more at risk of fire, it is argued, while they do little to suck up greenhouse gases.
Instead, the authors said we should prioritise conserving and restoring intact ecosystems.
Planting trees in vast schemes to ‘offset’ carbon emissions is harming nature, a new Oxford study claims
READ MORE: Carbon off-setting scheme supported by Sir Elton John on behalf of Prince Harry and Meghan Markle has no ‘meaningful’ effect on climate change
Writing in the journal Trends in Ecology and Evolution, scientists from the Environmental Change Institute at Oxford University said the focus on offsetting carbon at all costs damages other aspects of the ecosystem.
Author Dr Jesús Aguirre-Gutiérrez said: ‘Despite the broad range of ecosystem functions and services provided by tropical ecosystems, society has reduced value of these ecosystems to just one metric – carbon.
‘Current and new policy should not promote ecosystem degradation via tree plantations with a narrow view on carbon capture.’
Although some projects reforest degraded land, most involve what is known as afforestation – planting forests in undegraded and previously unforested regions such as grasslands.
Tropical ecosystems are highly biodiverse, and provide multiple ecosystem services, such as maintaining water quality, soil health, and pollination.
In comparison, carbon-capture plantations are usually monocultures and are dominated by just five tree species, teak, mahogany, cedar, silk oak, and black wattle, grown for timber, pulp, or agroforestry.
The result is that these plantations usually support a lower level of biodiversity.
For example, in the Brazilian Cerrado savannah, a 40 per cent increase in woody cover reduced the diversity of plants and ants by approximately 30 per cent.
In fact tropical grasslands and savannahs are already carbon sinks and, unlike trees, are less susceptible to disturbances such as drought and fire.
These plantations can also directly degrade ecosystems by reducing stream flow, depleting groundwater, and acidifying soils.
Dr Aguirre-Gutiérrez said: ‘The current trend of carbon-focused tree planting’ is creating monocultures for ‘little carbon gain’.
He added: ‘An area equivalent to the total summed area of USA, UK, China, and Russia would have to be forested to sequester one year of emissions.’
READ MORE: Climate change is having a bigger impact on rainforest ecosystems than deforestation
Climate change is having a bigger impact on the rainforest than deforestation, a new study of mammals in South America claims.
Researchers at the Field Museum in Chicago say that while logging causes some local animal populations to die out, global warming wipes out entire species.
Previously, it was believed the multi-billion-dollar logging industry posed the biggest threat to ecosystems, but researchers now say climate change has a bigger impact.
Lead author Professor Noe de la Sancha said ‘Save the Rainforests’ is a snappy slogan but it doesn’t tell the full story of how complicated it is to do just that.
He said they’ve created a detailed measure of biodiversity by looking at the variety of species and their place in the ecosystem, rather than the total number of creatures.
By measuring characteristics like ear, foot, and tail size in species like Euryoryzomys russatus, researchers can quantify functional diversity in large rainforests