Quantification of the food-water-energy nexus in urban green and blue infrastructure: A synthesis of the literature

Green and blue infrastructure (GBI) is an innovative strategy to tackle food-water-energy (FWE) nexus issues. GBI can provide the benefits of food production, energy saving and generation, waterlogging control, rainwater cleansing and harvesting. Significant efforts have been devoted to measuring the implications of GBI on FWE nexus. However, there is little research to simulate the multiple linkages between GBI and FWE nexus in urban areas, and the lack of a unified methodology framework also easily leads to an understanding bias of their connections and makes it challenging to compare the results. Focusing on the prior published literature, this study clarifies the interactions between GBI and FWE nexus and reviews the methods to quantify the implications of GBI on FWE nexus in cities, including FWE-related benefits, life cycle environmental impacts, and avoided upstream environmental footprints induced by FWE-related benefits. It is revealed that most studies focus on the FWE-related benefits or (and) life cycle environmental impacts of GBI from a silo perspective. Researchers pay little attention to the avoided trans-boundary environmental footprints by GBI, and carbon footprint is the greatest concern in the existing research. There is little evidence on comprehensive quantifications regarding multiple impacts of GBI on FWE nexus at the urban scale. The review outlines methods to simulate the linkages between GBI and FWE nexus and calls for a holistic methodological framework to apply at the urban scale. Such assessment practices would make sense for FWE-oriented resilience planning and governance for urban GBI implementation.