Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang, China

Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation. The Tianchi Bogda Peak Natural Reserve(TBPNR), located in Xinjiang Uygur Autonomous Region, China, is an important ecological barrier area in the temperate arid zone. The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve. In the present study, we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP), water yield, soil conservation, and habitat quality) in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(In VEST) model. In addition, the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis, and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector. During the study period, NPP and soil conservation values in the reserve increased by 48.20% and 25.56%, respectively; conversely, water yield decreased by 16.56%, and there was no significant change in habitat quality. Spatially, both NPP and habitat quality values were higher in the northern part and lower in the southern part, whereas water yield showed an opposite trend. Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation, and exhibited a trade-off relationship with water yield. Water yield and habitat quality also had a trade-off relationship. NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI), respectively, while water yield and soil conservation were more affected by digital elevation model(DEM). Therefore, attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management. The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China.