Systematic conservation planning considering ecosystem services can optimize the conservation system in the Qinling-Daba Mountains

Protected area are the cornerstone of biodiversity and ecosystem service conservation at the local, regional, and global levels. In 2019, China proposed the establishment of a nature reserve system (NRS)centered on national parks, integrating and improving various existing protected areas. This study focuses on the Qinling-Daba Mountains, an area crucial for both biodiversity and ecosystem services. Through assessments of carbon storage (CS), water yield (WY), soil conservation (SC), and habitat quality (HQ), different conservation scenarios are considered in the context of Systematic conservation planning (SCP). An optimization scheme for the NRS in the Qinling-Daba Mountains is proposed, incorporating ecosystem services and comparing them with the existing system. Research indicates that the main protected areas are concentrated in the Min Mountain-Motian Mountain-Longmen Mountain region, the central Qinling region, and the Shennongjia-Daba Mountain region. Compared with the original system, the area of protected regions in the NRS expanded by 52,000 km2 after the SCP scheme was incorporated. The number of patches decreased to 50, and the patch density reduced from 2.1 x 10-4(/100 ha) to 1.7 x 10-4(/100 ha), thereby reducing the fragmentation of the conservation system. Additionally, the optimized scheme achieved a conservation ratio of over 30% for CS, WY, SC, and HQ, with the conservation efficiency for WY and HQ increasing by 0.18 and 0.22, respectively. The study results provide support for optimizing the Qinling-Daba Mountains NRS and offer a reference for constructing NRSs in other regions. Considering ecosystem services in the optimization of the NRS helps enhance the supply capacity of ecological products, maintain national ecological security, and achieve harmonious coexistence and sustainable development between humans and nature.