A new study has found that the carbon sink potential of forests recovering from deforestation does not align with the current rate of deforestation.
The global study, led by the University of Bristol, has revealed the carbon sink vulnerability of recovering forests. Tropical forests are vital in the fight against climate change and have great potential as a carbon sink. However, the new data shows that new tropical deforestation and forest degradation are outstripping current rates of forest regrowth.
The research, ‘The carbon sink of secondary and degraded humid tropical forests,’ published in the journal Nature, demonstrates the potential of these ecosystems as a carbon sink and outlines the current limits of forest regrowth to address climate change and ecological emergencies.
The results underscore the importance of sustainable forest management
The findings revealed that degraded forests recovering from human and environmental damage, such as fire and logging, are removing at least 107 million tonnes of carbon from the atmosphere annually. The team used satellite data across the world’s three largest tropical forests to quantify the rates of aboveground carbon stock recovery.
Although the results show that recovering forests have the potential as a carbon sink, the amount of carbon being taken up in aboveground forest growth only counterbalanced around a quarter (26%) of the current carbon emissions from tropical deforestation and degradation.
Dr Viola Heinrich, lead author of the study, said: “Our study provides the first pan-tropical estimates of aboveground carbon absorption in tropical forests recovering from degradation and deforestation.
“While protecting ancient tropical forests remains the priority, we demonstrate the value in sustainably managing forest areas that can recover from human disturbances.”
Analysing the vulnerability of the carbon sink in recovering forests
The team used satellite datasets that can distinguish between different types of human disturbances, such as logging, fire, and deforestation, to determine the types of forests regrowing. They modelled the spatial patterns of forest regrowth in the Amazon, Central Africa, and Borneo by combining the satellite data with information on aboveground carbon from the European Space Agency.
The type of human disturbances in Borneo resulted in the greatest carbon reductions in degraded forests, due to the high-intensity logging of economically valuable trees, compared to the Amazon and Central Africa. As well as this, Borneo’s climate and environment also result in carbon accumulating about 50% faster than in the other regions.
“The carbon recovery models we developed can inform scientists and policymakers on the carbon storage potential of secondary and degraded forests if they are protected and allowed to recover,” said Heinrich.
Co-author Dr Jo House, Reader in Environmental Science and Policy at the University of Bristol, said: “Countries have repeatedly made pledges to reduce deforestation and forest degradation and restore deforested areas.
“This is the most cost-effective and immediately available way to remove carbon from the atmosphere, alongside many co-benefits such as biodiversity, flood control and protection of indigenous peoples’ livelihoods. Yet targets are repeatedly missed due to a lack of serious international co-ordinated support and political will. Our research demonstrates that time is running out.”
Co-author Dr Luiz Aragão, Head of Earth Observation and Geoinformatics Division at the National Institute for Space Research (INPE) in Brazil, added: “Focusing on the protection and restoration of degraded and secondary tropical forests is an efficient solution for building robust mechanisms for sustainable development of tropical countries. This aggregates monetary value for the local to global environmental services provided by these forests, in turn benefiting local populations economically and socially.”
Now, the team will build on this research to further understand the carbon sink potential of forests, improving the estimates of carbon losses and gains from different types and intensities of forest disturbance across the tropics.
