Human activities are responsible for the decline in biodiversity observed by scientists for several decades. So far, it has been mainly the change in land use that harms nature. But in the future, the effects of climate change could take precedence.
Ipbes, the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, is a bit like the IPCC of biodiversity. According to its experts, land use change is the main factor in the decline of biodiversity observed in the 20th century. But to what extent? An international team of researchers is now providing numbers. Land use change alone is said to be responsible for a decrease of 2 to 11% in global biodiversity.
Scientists claim that this is the most comprehensive estimate to date of the impact of habitat reduction and fragmentation on biodiversity evolution. It is based on thirteen models covering all regions of the world. This sets it apart from previous studies that worked 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 show that while land use has long been the main 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 – the combined effects of land use change are responsible for the biodiversity loss.Concerning lands and climate change will lead to biodiversity loss worldwide. Although significant variations exist between regions, models, and scenarios. Preserving biodiversity is seen as a solution to the climate crisis. The goal is not to make predictions but to implement policies that help avoid undesirable outcomes. An integrated approach is necessary 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 negative synergistic effects of land use and climate change on biodiversity, conservation and restoration efforts should be a global priority as essential natural climate solutions. Scientists warn that current policies are insufficient to meet international biodiversity preservation goals. Greater efforts and ongoing evaluation of policy impacts to identify the most effective approaches are recommended.