Sustainability of an economy from the water-energy-food nexus perspective

In this paper we study the usefulness of the water-energy-food nexus in assessing the sustainability of an economy. All economic activity depends on its surrounding physical environment, and especially on the interconnection between these three essential resources. As a result, the nexus is a useful tool for detecting the economic risk of resource scarcity, optimising investments or resource use, and assessing the effects of economic policies or shocks such as climate change. The nexus approach is also useful for guiding policies towards achieving the United Nations Sustainable Development Goals (SDGs). We show that both the objective of each study and the scale on which it is conducted are factors worth considering when choosing the most suitable research methodology. We detected important challenges relating to the heterogeneity of the methods, scales and variables used, and therefore necessary measures nare suggested in order to homogenise the studies for their comparability and/or integration, both horizontally and vertically, or over time.[Graphical Abstract]