Multivariate assessment of metropolitan sustainability with a focus on demand and supply food aspects: Insights into the metropolitan city of Venice

According to the United Nations "World Urbanization Prospects 2018", more than half of the population lives in metropolises and estimates that in 2050 almost 70 % of the world's population will live in urban areas. The unstoppable growth, the complexity, and the challenges in promoting the sustainable growth of metropolitan areas have thus attracted increasing attention from researchers and policy makers in recent years. At the EU level, the relationship between metropolitan cities and food has also become a focus. Despite often being neglected, food has a significant impact on the sustainability of metropolitan cities development. Thus, the aim of this work is to assess the sustainability of metropolitan areas, with a specific focus on the metropolitan city of Venice (Italy), using socio-demographic, economic, and environmental indicators/attributes, as well as local food demand and supply proxies. To achieve this objective a multi-step procedure based on Rough Set Theory and Dominance-Based Rough Set has been implemented. The results show that food attributes seem not to play a major role in shaping the metropolitan area's sustainability. However, when demand and supply food aspects are considered as a decision attribute, their connections with other sustainability indicators become apparent, particularly population density and tourism intensity in the socio-demographic pillar, and land consumption in the environmental one.