An increasing world population is projected to increase water, energy and food requirements, three vital resources for humankind. Projected climate change impacts will aggravate water availability, as well as flood risks, especially in urban areas. Nature-based solutions (NBS) have been identified as key concepts to defuse the expected tensions within the Water-Energy-Food (W-E-F) nexus due to their multiple benefits. In this paper, the authors outlined the theories and concepts, analyzed real-life case studies, and discussed the potential of NBS to address the future W-E-F nexus. For this purpose, we performed a systematic literature review on the theories of NBS that address the W-E-F nexus, and we summarized 19 representative real-life case studies to identify the current knowledge gaps and challenges. The quantitative and qualitative data was used to differentiate and discuss the direct and indirect potential benefits of NBS to the W-E-F nexus. The study further expanded on the challenges for the implementation of NBS and highlighted the growing possibilities in the context of circularity and the implementation of NBS in urban planning. It was concluded that the potential impacts of NBS on the W-E-F nexus have been identified, but the quantitative effects have not been analyzed in-depth. Moreover, indicators are mostly single-purpose and not multipurpose, as required to fully characterize the W-E-F nexus and circularity holistically. Overall, there is a need to adopt systemic thinking and promote the multipurpose design of NBS.

There is limited focus on the water-energy-food (WEF) nexus approach at the local scale, particularly considering the social contexts of neglected territories. To contribute to this debate, we propose a framework to address this topic in an area in Angra dos Reis, Rio de Janeiro State, Brazil, as a case study. A survey was conducted regarding residents’ perceptions, choices, practices and access to water, energy, and food. The interviews highlighted important topics on the WEF nexus. As a result, a set of 12 indicators with data available on official datasets was proposed, reflecting residents’ perceptions of WEF safety. For each indicator, thresholds were established based mainly on the goals defined by Brazilian policies across different spheres—federal, state, or municipal. Thus, each indicator is multi-scale and integrative, since it comprises a local perspective (from the interview results), an official perspective (from the official databases), and a threshold. The results showed problems with energy and water supply, and the presence of home cropping, contrasting with residents who do not have access to basic food and experience extreme poverty. All these elements drew attention to the possibility of applying the WEF nexus approach, searching for feasible solutions which can support better decisions and governance in neglected territories.

There is limited focus on the water-energy-food (WEF) nexus approach at the local scale, particularly considering the social contexts of neglected territories. To contribute to this debate, we propose a framework to address this topic in an area in Angra dos Reis, Rio de Janeiro State, Brazil, as a case study. A survey was conducted regarding residents&rsquo: perceptions, choices, practices and access to water, energy, and food. The interviews highlighted important topics on the WEF nexus. As a result, a set of 12 indicators with data available on official datasets was proposed, reflecting residents&rsquo: perceptions of WEF safety. For each indicator, thresholds were established based mainly on the goals defined by Brazilian policies across different spheres&mdash:federal, state, or municipal. Thus, each indicator is multi-scale and integrative, since it comprises a local perspective (from the interview results), an official perspective (from the official databases), and a threshold. The results showed problems with energy and water supply, and the presence of home cropping, contrasting with residents who do not have access to basic food and experience extreme poverty. All these elements drew attention to the possibility of applying the WEF nexus approach, searching for feasible solutions which can support better decisions and governance in neglected territories.

There is limited focus on the water-energy-food (WEF) nexus approach at the local scale, particularly considering the social contexts of neglected territories. To contribute to this debate, we propose a framework to address this topic in an area in Angra dos Reis, Rio de Janeiro State, Brazil, as a case study. A survey was conducted regarding residents' perceptions, choices, practices and access to water, energy, and food. The interviews highlighted important topics on the WEF nexus. As a result, a set of 12 indicators with data available on official datasets was proposed, reflecting residents' perceptions of WEF safety. For each indicator, thresholds were established based mainly on the goals defined by Brazilian policies across different spheres-federal, state, or municipal. Thus, each indicator is multi-scale and integrative, since it comprises a local perspective (from the interview results), an official perspective (from the official databases), and a threshold. The results showed problems with energy and water supply, and the presence of home cropping, contrasting with residents who do not have access to basic food and experience extreme poverty. All these elements drew attention to the possibility of applying the WEF nexus approach, searching for feasible solutions which can support better decisions and governance in neglected territories.