Responses of spatial relationships between ecosystem services and the Sustainable Development Goals to urbanization.

Ecosystem services (ES) are the important component supporting the United Nations Sustainable Development Goals (SDGs) realization. In recent decades, rapid urbanization has strongly affected the relationship between ES and SDGs, resulting in the decoupling of ES and SDGs. However, the key urbanization factors dominating the relationship between ES and SDGs are still unclear. In this study, a structural equation model was constructed to explore the impact path and its change of urbanization structure and scale factors on the relationship between ES and SDGs. The results showed that the economic urbanization structure indicator (Engel coefficient) under the influence of technology import significantly impacted the relationship between ES and SDGs in different periods. Under the influence of changes in urban and rural population, population urbanization structure indicator (labor force population proportion) had significant impact on the relationship between ES and economic SDGs, which was significantly stronger in the period of 2010-2015 than in the period of 2000-2005. Land urbanization scale indicators (construction land proportion, and protected natural area proportion) also significantly impacted the relationship between ES and SDGs. Especially for ecological SDGs, the negative impact of construction land on protected natural area increased significantly in the period of 2010-2015, which might further weaken the ES's contribution to SDGs. This study highlighted that along with the continuous transformation of China's society, the key impacts on the relationship between ES and SDGs resulted from the urbanization indicators of scale as well as structure, which provided an extensive support for the sustainable development and social transformation of developing countries and regions.