Biodiversity-driven spatial conservation planning to delineate temporally stable regions

The accelerating loss of biodiversity underscores the critical need for effective conservation strategies, particularly in the face of climate change and anthropogenic pressures. We devised a conservation planning framework that adopts a temporal stacking approach to species distribution models and landscape connectivity analyses. These models and analyses were derived from an integrated modeling and post-modeling GIS workflow and used to identify and propose conservation priority areas, also quantifying the proportion of these areas covered by existing protected areas (PAs). We applied the approach, as an example, to the genus Salamandrina, the oldest Salamandridae clade, because of its conservation and biogeographic importance. Our approach can be applied to any taxon. Specifically, we introduced and identified the steady core regions (i.e., areas predicted to remain ecologically suitable for the next 50 years) for Salamandrina. The geographic configuration of these areas, including their clustering and fragmentation degree, differed between distance-informed and distance-uninformed approaches along the Apennine chain. Those occurred in nationally designated PAs (few, large patches) and Natura 2000 sites (many and small patches), but steadiness values were generally low (often <5 out of 13), indicating scarce legal protection of temporally stable areas. We therefore propose 2 strategies to delineate areas currently unprotected that should be prioritized to reach the 30% of territories protected by 2030: increasing existing PA boundaries by estimating buffer distances and inferring stable areas outside current PAs, which we term half-century stable proposed protected areas (HCSPPAs). The buffering approach indicated a required 1-km expansion. The HCSPPAs clustered near existing PAs in northern and central Italy. In southern Italy, they were fewer and more dispersed, ranging from close to distant locations relative to current PAs. Our approach aligns with the European Union's 2030 Biodiversity Strategy and the global 30×30 conservation target because it provides a flexible and spatially informed framework to prioritize biodiversity conservation and strengthen long-term species' protection.