Assessing a mammal-based bioclimatic ecosystem resilience index (BERI) under climate change scenarios in South Korea

Climate change threatens global biodiversity, and quantitative assessment of ecosystem resilience is essential for climate-adaptive conservation. The Bioclimatic Ecosystem Resilience Index (BERI), a component indicator of Target 8 of the Kunming-Montreal Global Biodiversity Framework (KM-GBF), quantifies the capacity of terrestrial ecosystems to retain biodiversity under climate change by integrating habitat condition, connectivity, and compositional similarity. However, no study has independently calculated BERI for South Korea. This study assessed a nationwide BERI under multiple climate change scenarios using Korean species records and environmental variables. Records of 29 terrestrial mammal species from four national biodiversity surveys were compiled with topographic and bioclimatic variables. Habitat condition was assessed using the InVEST Habitat Quality model with parameters from ensemble species distribution models, compositional similarity using Generalized Dissimilarity Modeling (GDM), and connectivity using least-cost path analysis. BERI was calculated at 5-km resolution under four SSP scenarios across three future periods. The national-scale mammal-based BERI was 0.344, with higher values along the Baekdudaegan mountain range and in major national parks (Seoraksan and Jirisan) and lower values in coastal and urbanized lowlands. BERI generally declined with increasing emissions and longer time horizons, with spatial heterogeneity: central inland forests had the largest decreases, whereas some southern coastal areas showed relative increases. BERI correlated most strongly with slope (r = 0.45), roughness (r = 0.45), and elevation (r = 0.42). This study provides the first independent national-scale BERI assessment for South Korea, providing a scientific basis for implementing KM-GBF Target 8 and for strategically identifying other effective area-based conservation measures (OECMs).