Assessment of the protective role of China's nature reserves based on GAP Analysis:An analysis of terrestrial mammals

Mammals hold crucial significance in the realm of biodiversity conservation. Nature reserves serve as vital zones that effectively mitigate the loss of species diversity. Based on equal-area grid, this study evaluates the abundance patterns of terrestrial mammals across different levels of threats, analyzes regions and species under protection gaps, considering both the broad scale of nature reserves and the finer scale of protective patches. However, there are limited traditional gap analyses that fully take into account the diversity of species and their spatial requirements. We integrate the concept of Minimum Area Requirement (MAR) of species populations as a new supplementary assessment metric to assess the sufficiency of nature reserve patches, and species with poorer compliance are considered as the candidate species under conservation gaps, replacing the single threshold division approach with a multispecies threshold estimation method. The results show that: (1) The richness of threatened terrestrial mammals decreases progressively from the biodiversity-rich southwest to the north, highlighting the importance of Southwest China, particularly Yunnan province, as a critical biodiversity hotspot. Additionally, seven key regions are identified as conservation gap areas, where nature reserves fail to provide sufficient coverage for the protection of threatened species. (2) The distribution ranges of a total of 92.06% of the threatened species overlap with existing nature reserves, however, the presence of the overlaps does not ensure the provision of sufficient conservation, as evidenced by the fact that seven mammal species classified as endangered and three mammal species categorized as vulnerable are subject to absence of protection coverage. (3) Half of the protected patches for each of twenty-two nationally important threatened species face area limitations under different population growth rate levels. The results hold significant implications for identifying priority conservation areas and optimizing the planning of nature reserves to safeguard mammalian biodiversity.