Urbanization is a key factor that threatens the stability of ecosystem services (ESs), which are crucial for maintaining ecological security and enhancing human quality of life. Gaining insight into the spatiotemporal differentiation of the ecosystem service value (ESV) and its coupling relationship with urbanization is a key issue in promoting sustainable regional development. We employed various algorithms, including the improved equivalence factor method, random forest model, mixed geographically and temporally weighted regression model, and coupling coordination degree (CCD) model, to reveal the spatiotemporal evolution of the ESV and its driving mechanisms in the Lanzhou-Xining urban agglomeration (LXUA) from 1980 to 2020. In addition, we explored the coupling relationship between ESV and the combined urbanization index (CUI). The results showed the following: (1) From 1980 to 2020, the interannual variation in ESV first decreased and then increased, with an increase of 230 million yuan/annum in 2020 compared to that of 1980. Spatially, the ESV exhibits a distribution pattern of high in the south and low in the north, and high in the west and low in the east. (2) Land use intensity (LUI) and elevation contributed degree values exceeding 20% to the ESV and were the most important drivers of the ESV. (3) From 1980 to 2020, the average CCD values of the ESV and CUI transitioned from being severely unbalanced (0.19) to being slightly balanced (0.42). There was a negative spatial correlation between the ESV and CUI, with each cluster type was distributed discretely in space. Our study emphasizes that in areas characterized by robust ecosystem integrity and a high ESV, the increase in LUI was constitutes the main reason for the decline in the ESV. The findings of this study can provide a scientific basis for the coordinated development of ESVs and urbanization in the LXUA and other cities.

中文翻译：

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生态系统服务价值时空分异及其与城市化的耦合关系——以兰西城市群为例

城市化是威胁生态系统服务稳定性的关键因素，而生态系统服务对于维护生态安全和提高人类生活质量至关重要。深入了解生态系统服务价值（ESV）的时空分异及其与城市化的耦合关系是促进区域可持续发展的关键问题。采用改进的等价因子法、随机森林模型、时空混合加权回归模型、耦合协调度模型等多种算法，揭示了兰州至西宁地区ESV的时空演化及其驱动机制。 1980年至2020年城市群（LXUA）。此外，我们探讨了ESV与综合城市化指数（CUI）之间的耦合关系。结果表明：（1）1980-2020年ESV年际变化先减小后增大，2020年比1980年增加2.3亿元/年。空间上ESV呈现出分布规律南高北低，西高东低。 （2）土地利用强度（LUI）和海拔对ESV的贡献度值超过20%，是ESV最重要的驱动因素。 （3）从1980年到2020年，ESV和CUI的CCD平均值从严重不平衡（0.19）转变为轻微平衡（0.42）。 ESV和CUI之间存在负空间相关性，各簇类型在空间上离散分布。我们的研究强调，在生态系统完整性强且ESV较高的地区，LUI的增加是ESV下降的主要原因。本研究结果可为LXUA及其他城市ESV与城镇化协调发展提供科学依据。