Blue-green infrastructure provides a variety of ecosystem services and is becoming an increasingly vital part of urban ecosystem protection. It is an ecological facility for ecological conservation and environmental protection, and a foundation for realizing people's needs for a better life. This study selects indicators from four dimensions: social, economic, environmental, and ecological, and the demand for blue-green infrastructure is assessed comprehensively. The results show that: (1) the demand for blue-green infrastructure varies spatially with the development of the city; (2) the total demand for blue-green infrastructure in Nanjing from 2000 to 2020 shows a pattern of "high in the center and low in the periphery"; (3) the level of economic development, urban spatial pattern, and decision management orientation have different degrees of influence on the demand for blue-green infrastructure, with the urban spatial pattern having the greatest impact. Therefore, in the future, blue-green infrastructure should be optimized by taking into account the spatial characteristics of demand in Nanjing.
Keywords: Nanjing; blue–green infrastructure; influencing factors; measurement of demand; spatial and temporal differences.