Biodiversity isn’t enough
Over the last few decades, the conservation community has quite rightly emphasised the importance of protecting biodiversity, both for its intrinsic value and because of its key role in maintaining ecosystem services. However, this story requires an important addition: the closer an ecosystem is to its natural condition (that is, the higher its ecosystem integrity), the more benefits it provides. In more technical terms, ecosystems that retain all or almost all of their biodiversity, including their natural species composition and vegetation structure, maximise many ecosystem services while minimising the risk of their loss.
Why ecosystem integrity matters
Primary forests, for example, have a high degree of ecosystem integrity and as a result protect more biodiversity and store more carbon than degraded forests and plantations. Primary forests are also more resistant to climate-related impacts like droughts, heatwaves and wildfire. Their ecosystem carbon stocks are also more stable and at lower risk of emitting CO2 into the atmosphere than a degraded forest. Moreover, the closer an ecosystem is to its natural condition, the more likely it will be able to adapt to changing climatic conditions.
The unique power of Primary Forests
The ecological integrity of primary forests, for example, is shaped by the complex web of life they support. Protecting all components of this biodiversity, including rare and endangered species and unique species assemblages is essential to maintaining ecosystem services. Primary forests grow huge old trees that create an optimal forest-interior microclimate with cooler temperatures and higher humidity for forest-dependent plants and animals. These forests sequester and store vast amounts of carbon and contain valuable genetic information that helps in resisting environmental stressors. They also develop a thick layer of leaf litter and dead wood which helps bacteria and fungi cycle nutrients, protects from soil erosion, and contributes to carbon storage.
Thus, the characteristic biodiversity and ecosystem structure of a primary forest, assembled gradually over eons, fundamentally underpins the ability of primary ecosystems to deliver superior ecosystem services. But primary forests are very quickly lost to industrial disturbance and only slowly recover – if recovery is possible at all. Their unique biodiversity and ecosystem structure is what makes them irreplaceable, and such a high priority for protection.
These unique characteristics are why we and a number of colleagues drafted Motion 015, which will be discussed at the IUCN World Conservation Congress 2025. The motion urges IUCN to prioritise ecosystem integrity in global conservation and climate agendas, and to recognise the critical role primary forests play in safeguarding biodiversity, stabilising climate, and upholding the rights of Indigenous Peoples.
Progress on the global stage
Significant progress was made in Montreal and later in Cali in affirming the importance of retaining and restoring ecosystem integrity in the Kunming-Montreal Global Biodiversity Framework (GBF). In particular, ecosystem integrity and the need for maximising synergistic action was strongly emphasised in the climate and biodiversity decision from Cali. This was a big step forward. It also supports the UN’s goal of halting both deforestation and forest degradation as noted in the UN's Strategic Plan for Forests 2017-2030, and echoed in the Glasgow Declaration on Forests and Land Use in 2021. However, more needs to be done in the UNFCCC to recognise the climate mitigation and adaptation benefits of protecting carbon dense ecosystems like primary forests. Close collaboration between the CBD and the UNFCCC is essential to ensure progress is not hindered by siloed approaches.