The ecological conservation of nature reserves has garnered considerable attention and is subject to stringent management in China. However, the majority of these areas have a history of underdeveloped economies and require urgent improvements in the well-being of local communities. Effectively coupling and harmonizing the dynamic relationship between ecosystem services and socio-economic development has emerged as a crucial concern for nature reserves. Therefore, further exploration is needed to achieve a spatio-temporal balance and alignment between the supply and demand of ESs in nature reserves in China. Utilizing multiple datasets, RULSE, and bivariate autocorrelation methods, this study investigated the spatio-temporal evolution of the ecosystem services supply–demand ratio (ESDR) and supply–demand spatial matches for soil conservation services (SCSs) in the Qinling Mountains (QMs) from 2000 to 2020. The results indicated the following: (1) Over the years, the supply of SCSs exhibited a consistently high level, with an upward trend observed in 63.10% of the QMs, while the demand for SCSs is generally low, with a decreasing trend observed in 82.68% of the QMs. (2) The supply and demand of SCSs remained favorable, with a positive ESDR reaching 82.19% of the QMs. From 2000 to 2010, there was a significant decline in ESDR; however, a substantial rebound was observed in the ESDR across the region from 2010 to 2020. (3) Over years, the majority of counties and districts exhibited positive values in ESDR. When examining cities, Weinan, Xi’an, and Ankang demonstrated relatively consistent patterns with higher ESDR values over time. In 2000, the ESDR on the northern slope exhibited lower values than that on the southern slope; however, this situation subsequently underwent a reversal. (4) The spatial distribution of SCS supply and demand was predominantly characterized by matching regions exhibiting either High Supply–High Demand or Low Supply–Low Demand for years. This study suggests that the supply and demand dynamics of SCSs in the Qinling Mountains have been favorable in recent years, with consistent spatial supply–demand matches. These findings can provide valuable insights for similar nature reserves aiming to implement ecological environmental protection and achieve sustainable development. The future research endeavors, however, should strive to expand upon these findings by exploring the supply and demand patterns associated with other ESs across diverse nature reserves, while considering their unique geographical characteristics, in order to promote more rational ecological management strategies.
