Food-energy-water (FEW) nexus for urban sustainability: A comprehensive review

The emerging popularity of the nexus discussion reflects the ongoing transition from a sectoral or silo approach to an integrative approach to address the global challenges pertinent to the three essential resources: food, energy, and water (FEW). Cities are critically important for advancing regional sustainable development and are thus placed at the center of the FEW nexus. This paper provides a comprehensive literature review to debate the current concepts and methods of the FEW nexus at different scales, with the aim of developing a conceptual knowledgebase framework for scientific analysis and policy making associated with the urban FEW nexus. Although the concept of nexus thinking has been widely accepted, a consistent and explicit cognition of the FEW nexus is still lacking, and a sophisticated methodological modeling framework is urgently required at various scales. As such, we proposed a three-dimensional conceptual framework of the urban FEW nexus from the perspective of resource interdependency, resource provision and system integration. This framework is useful in steering the systematic modeling and integrative management of the complex nexus issues of urban systems with different perspectives. Finally, the future directions of urban nexus research are identified from four aspects, including systematic characterization, cross-region tele-connection mechanisms, co-decision model development, and governance transition.