Ecosystem service bundle index construction, spatiotemporal dynamic display, and driving force analysis

Introduction: Existing studies on ecosystem service relationships are mainly qualitative or semi-quantitative assessments, but lack of quantitative exploration of aggregated ecosystem services and their influencing factors. We mapped the distributions of 12 ecosystem services of Zhejiang Province in 2000 and 2015 at the district and county level, analyzed their relationships using Spearman's correlation analysis, constructed ecosystem service bundle index (ESBI) for each district and county by structural equation model, and then through multiple linear regression, we explored factors associated with ESBI variations. Outcomes: Our results showed that (1) most ecosystem services were spatially clustered. There were synergies between individual ecosystem services in categories of provisioning and regulating services, respectively; (2) our proposed ESBI index system consists of overall index and sub-indices of provisioning, regulating, and cultural services. The higher the ESBI value, the more important the corresponding place for multiple aggregated ecosystem service provision. Compared to 2000, ESBI in 2015 distributed more unevenly, and the average dropped by 3.10%; and (3) the increase of ESBI was associated with its initial value, and four socioeconomic and natural factors; the decrease of ESBI was influenced by the initial value and six key socioeconomic factors. Discussion and Conclusion: Our proposed ESBI system has several advantages (e.g., scale free, flexible weighting, quantitative and continuous indices for further analyses, and alternative non-monetary solution) in understanding and managing relationships among multiple ecosystem services.