Human activities have been responsible for the decline in biodiversity observed by scientists for several decades. So far, it has mainly been land use change that harms nature. However, the effects of climate change could overshadow this in the future.
The IPBES, the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, is akin to the IPCC for biodiversity. According to its experts, land use change is the primary factor in the observed decline of biodiversity in the 20th century. But to what extent? An international team of researchers is now providing figures. Land use change alone could be responsible for a 2 to 11% decrease in global biodiversity.
Scientists claim that this is the most comprehensive estimate to date of the impact of habitat reduction and fragmentation on biodiversity. It is based on thirteen models covering all regions of the world. This sets it apart from previous studies that relied on fragmented and potentially biased data.
Researchers have also calculated the simultaneous impact of land use change on what are known as ecosystem services. These are the benefits that nature provides to humans. Over the past century, there has been a massive increase in the provision of ecosystem services, such as food and timber production. However, ecosystem regulation services, such as pollination, nitrogen retention, or carbon sequestration, have moderately decreased.
Human Activities at the Heart of Biodiversity Decline
The models developed by the team also allow for some projections. These projections show that while land use has long been the primary factor in biodiversity loss, it could be surpassed by another human-induced factor by the middle of this century: climate change.
Researchers explain in the journal Science that, regardless of the scenario considered – from one that relies on true sustainable development to one where greenhouse gas emissions remain high – theCombined effects of land use change and climate change will lead to biodiversity loss. This will occur in all regions of the world, although significant variations are expected based on regions, models, and scenarios. Preserving biodiversity is seen as a solution to the climate crisis. The analysis emphasizes the need for an integrated approach to sustainability to reduce conflicts between policies and safeguard biodiversity in the future. For instance, while bioenergy deployment is crucial for most climate stabilization scenarios, it also poses a threat to species habitats. Given the synergistic negative effects of land use and climate change on biodiversity, conservation and restoration efforts should be prioritized globally as necessary natural climate solutions. Current policies are deemed insufficient to meet international biodiversity preservation goals, highlighting the necessity for increased efforts and ongoing evaluation of policy impacts to identify the most effective strategies.