Mega-city region sustainability assessment and obstacles identification with GIS–entropy–TOPSIS model: A case in Yangtze River Delta urban agglomeration, China

Sustainability is related to support the huge population and improve the residents’ well-being in the Mega-city regions. Sustainability assessment is necessary under the context of implementing the Sustainable Development Goals in 2030. Refer to SDG 11, this study constructed an index system, assessed the sustainability level based on the theory of ‘‘weak’’ and ‘‘strong’’ sustainability and screened obstacles of 26 cities in the Yangtze River...