The water-energy-food (WEF) nexus concept has emerged over the last decade as a way of thinking about and analysing natural resources. Each WEF sector has intimate feedback relationships with the other sectors, forming a coherent, complex system. Through analysis of these relationships and of the impact of policy on the system, more integrated and sustainable resources management is aimed for. The nexus concept is not without criticism, and a concern is that one sector would come to be seen as ‘more important’ than the others. This paper attempts to break such ideas, describing how each WEF sector is equally essential for the functioning of the other two, and that the WEF nexus is more than the sum of its parts. Going further, the paper shows how the WEF nexus is supported/enabled by ‘ecosystems’. Without good ecosystems functioning, the WEF sectors could be compromised with significant consequences. At the same time, ecosystems are degraded by WEF demand and exploitation. Society depends upon ecosystems and the proper quantity, quality, timing, and spatial availability of WEF resources. Societal demand impacts on WEF resources availability and security, and on ecosystems integrity. The paper concludes by stating that the integrity of this WEF-ecosystems system is under significant threat as planetary boundaries are exceeded, ecological overexploitation is accelerating, and global warming impacts become acute. Nothing short of a wholesale societal behavioural and conceptual shift towards WEF sectors, their use, exploitation, and management is required, and that a systems-thinking mentality is central to such a shift.

Integrated approaches for managing natural resources are said to meet increasing demand for water, energy, and food, while maintaining the integrity of ecosystems, and ensuring equitable access to resources. The Water-Energy-Food (WEF) Nexus has been proposed as a cross-sectoral approach to manage trade-offs and exploit synergies that arise among these sectors. Although not initially included as a component of the Nexus, the role of nature in sustaining the water, energy, and food sectors and in regulating their interrelationships is increasingly recognised by Nexus researchers and practitioners. To converge existing approaches that integrate nature into the WEF Nexus and suggest a common framework, we – an interdisciplinary group of natural resources management researchers and systems thinkers from the European research network NEXUSNET COST Action – followed a collaborative process of knowledge creation combining literature review, elicitation of expert opinion and collaborative writing. Our results reveal a multiplicity of concepts utilised in the literature to represent, partially or fully, “nature” in the Nexus, such as “environment”, “ecosystems”, “ecosystem services”, “social-ecological systems”, and “biodiversity”. Disparity was also found in the role attributed to nature, represented by three key paradigms: (1) ecosystems as the fourth component of an expanded Nexus, i.e., the WEF-Ecosystems (WEFE) Nexus; (2) ecosystems as a foundational layer to the Nexus; and (3) the WEF Nexus as a central component of social-ecological systems (SES). By creating a hybrid approach that brings together the benefits of the respective paradigms, we present a forward-looking WEFE Nexus conceptualisation. This paradigm expands the mutual interlinkages among water, energy and food to the entirety of SES, thus acknowledging the social-ecological processes that are affected by and affect the WEF Nexus. The results of this collaborative research effort intend to provide researchers and stakeholders with means to better understand and ultimately manage Nexus issues towards a transformative change.

The authors regret that there were two formatting mistakes: 1. Definitions of key “Nexus” and “ecosystems” terms appear as a paragraph on page 4 rather than within Box 1. The revised Box 1 is [Table presented] Box 1. Glossary of key terms. 2. The caption for Fig. 7 is separated from the figure and appears as a paragraph on page 15. The revised caption of Fig. 7 is[Figure presented] Fig. 7. Proposed hybrid WEFE Nexus paradigm – elements and interlinkages. Examples for some of the interlinkages are provided. Connection 4: the provisioning ecosystem service of wild foods, but also the expected trends due to planning and strategic conservation efforts that can lead to an increase in their availability and use (Sajeev et al., 2023). Connection 5: the provisioning ecosystem service of wood and biomass, as well as the influence of the energy sector on the use and management of land resources. Connection 6: provisioning of fresh water and water purification as ecosystem services, on one hand, and policy and governance measures for protection and preservation of aquatic habitats and biodiversity, prevention of overexploitation of freshwater, sustaining environmental flows from reservoirs, on the other. Connection 7: the social and governance processes involved in setting aside land and resources for new sectoral developments (e.g., a new reservoir), as well as constraints to such new developments arising from policy (e.g., the EU biodiversity strategy for 2030) and social dynamics; sectoral activities providing livelihoods; global and national agreements setting targets on emissions reductions, as well the socio-economic implications of decarbonization plans (Plazas-Niño et al., 2022), just transition plans (Wang and Lo, 2021), and the economic transformation towards net-zero economies, job creation in emerging sectors, innovation and investment, and social adjustments (Krishnan et al., 2022). Connection 8: the impact of infrastructure development in the water sector (e.g., a new reservoir) on freshwater ecosystems; the impact of agricultural expansion on terrestrial ecosystems; the influence of biotic and abiotic components of ecosystems on the WEF Nexus sectors: pests and diseases, invasive species, pollination, river flow regimes, including floods and low flows. The authors would like to apologise for any inconvenience caused.