Accelerating decline of habitat quality in Chinese border areas

Borderlands frequently intersect with areas of biodiversity, encapsulating a variety of critical ecosystems and serving as indispensable habitats for numerous cross-border species. With the development of geoeconomic collaboration and competition among neighboring countries, borderlands have been subjected to progressive acute threats to biodiversity, such as habitat quality (HQ). However, dynamic changes and driving factors of HQ in border areas have not been adequately examined. Here, take Chinese borderlands as an example, applying the InVEST model to meticulously analyze the spatio-temporal dynamics of HQ during 1985-2020 and further projecting potential trends over the next five years while identifying the predominant factors with the geo-detector method. The results show that a marked decline in HQ within a 60-km buffer zone of the Chinese borderlands and its four sub-regions (i.e., borderlands of northeast, northwest, southwest, and Tibet) since 1985, affecting about 30% of the total land area, a trend projected to escalate by 2025, especially in the biodiversity-rich southwestern border areas. Notably, natural factors such as vegetation cover, mean annual temperature, and precipitation have been identified as significant contributors to degradation of HQ, while socio-economic aspects, including road construction, are also increasingly impacting. Our findings about dynamic changes of HQ provides a scientific foundation and crucial insights for improving comprehensive biodiversity monitoring in the borderlands or cross-border areas.