Tree-planting schemes threaten tropical biodiversity for “little carbon gain,” argue ecologists from the University of Oxford.
While there has been an increase in tree-planting schemes to offset carbon emissions, the researchers argue the plantations might come with costs for biodiversity and other ecosystem functions.
Additionally, the paper argues that while the tree-planting schemes are economically viable, they usually support a lower level of biodiversity.
For example, in the Brazilian Cerrado savannah, a 40% increase in woody cover reduced the diversity of plants and ants by approximately 30%.
These plantations can also directly degrade ecosystems by reducing stream flow, depleting groundwater, and acidifying soils.
Instead, the authors say companies should prioritise conserving and restoring intact ecosystems.
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“The current trend of carbon-focused tree planting is taking us along the path of large-scale biotic and functional homogenisation for little carbon gain,” the authors wrote in their paper.
“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,” they added.
Author 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,” he added.
