Predicting habitat suitability of Korean Lindera as Tertiary relict plants under climate change scenarios

Climate change profoundly affects plant habitats and ecological niches, particularly among Tertiary relict flora-remnants of warm and humid climatic conditions that prevailed during the Tertiary period-which are recognized as highly climate-sensitive lineages. The genus Lindera (Lauraceae), a representative group of deciduous broad-leaved trees in East Asian temperate forests, provides an ideal model for examining shifts in habitat suitability and changes in predicted suitable environments under future climate change scenarios. In this study, we developed ensemble species distribution models (SDMs) using six algorithms to predict the distributions of four Lindera species-L. obtusiloba, L. glauca, L. erythrocarpa, and L. sericea-under three Shared Socioeconomic Pathway (SSP) scenarios (SSP1-2.6, SSP3-7.0, SSP5-8.5). Among the three categories of environmental variables, climatic factors exerted the greatest influence on habitat suitability, with temperature seasonality (bio4) and growing-season precipitation (gsp) identified as the primary determinants. With intensifying climate change, suitable habitats shifted northward and upward, accompanied by pronounced habitat losses across southern and central Korea. Despite its broad geographic range, L. obtusiloba exhibited an 81% reduction in suitable habitat, whereas L. sericea, due to its localized distribution, showed a 91% decrease and was identified as the most climate-vulnerable species. Ecological niche overlap (Schoener's D) declined across all scenarios, indicating increasing ecological differentiation among species. Although the four Lindera species exhibited distinct spatial responses, all consistently experienced range contractions and reduced overlap in predicted suitable environments, indicating high vulnerability to climate change. These results suggest that intrinsic ecological traits, climatic sensitivity, and niche stability-rather than current geographic range extent-are key determinants of species persistence. Accordingly, Lindera species in southern Korea should be considered climate-vulnerable taxa, and conservation strategies should integrate the protection of climatically stable refugia with complementary conservation measures beyond natural habitats to ensure long-term persistence under future climate change.