Modelling the paths ahead: Predicting future global biodiversity intactness under Nature Future Framework scenarios

Global biodiversity targets can be tackled through a variety of policy and implementation pathways. Understanding the potential implications of these alternate strategies is vital to navigating the tensions and synergies between biodiversity, land use, climate and socio-economic factors. The Nature Futures Framework (NFF) facilitates the development of scenarios that differ in how nature is valued – how the human-nature relationship is perceived. Whether we value nature for nature’s sake, for its utility to humans or for its cultural significance influences how land systems are managed towards achieving the 2030 targets of the Kunming-Montreal Global Biodiversity Framework (KM-GBF). For instance, where protected areas are established, how strictly they are managed, and the extent to which land-sharing versus land-sparing approaches are adopted when implementing targets 1–3 on conservation and restoration. Such decisions directly affect the biodiversity these systems can sustain, particularly given that land-use change is the predominant driver of terrestrial biodiversity shifts globally. Because biodiversity is at the core of the framework, the expectation is that NFF scenarios will be more nature-positive than those developed under the Shared Socioeconomic Pathways. However, so far, there have been few global biodiversity projections under alternative NFF scenarios. Here, we present a modelling framework that couples the PREDICTS database with the PLUM land-use model to produce global, 1-km resolution projections of the Biodiversity Intactness Index (BII) under four NFF scenarios and a business-as-usual future.  We show that these scenarios differ markedly from each other. Some regions exhibit far greater variability between scenarios than others, highlighting where policy choices may have the greatest impact for biodiversity. We also identify unintended consequences of interventions when implemented within broader socio-economic contexts, such as the displacement of timber extraction to previously unmanaged, but unprotected forests, when protected areas are managed strictly in a less globalised world. Across all NFF scenarios, achieving the 2030 targets of the KM-GBF leads to short-term biodiversity gains. However, long-term trends still point toward continued decline. These findings suggest that while current targets can deliver near-term benefits, they may fall short of the ambition required to meet 2050 goals to halt and reverse biodiversity loss.