Comparing and Mapping Historical Extinction Debts of Different Groups of Amphibians in Different Suitable Habitat Classes of China.

China's rapid urbanization and industrialization have profoundly altered land-use patterns, posing significant threats to amphibian biodiversity. Using species-area relationship models, we assessed extinction debts across five habitat types (farmland, forestland, grassland, water habitats, and general habitable areas) for amphibian species. Results demonstrate that historical extinction debts were paid off during 1980-2000, whereas new debts accumulated in forestlands, grasslands, and particularly aquatic habitats over the following two decades. Spatial analyses reveal elevated extinction debt magnitudes in southern China due to intensive land-use changes, contrasting with lower impacts in northern regions. Notably, extinction debts for threatened species are concentrated in the Sichuan Basin, Yunnan-Guizhou Plateau, Hainan, and Taiwan Province, highlighting critical conservation gaps. These findings underscore the necessity of habitat-specific protection strategies to mitigate biodiversity loss in high-risk zones.