| 21 Dec 2025
Towards an ideal water-energy-food nexus model: moving beyond silos to integrated resource governance
Abstract. The water-energy-food (WEF) nexus applies systems thinking to transcend siloed sectoral perspectives and foster integrated resource governance. This study identifies six key objectives that an ideal model for the WEF nexus should achieve: ensuring resource security; promoting resource circularity; enabling transferability across spatial and temporal scales and geographic scopes; facilitating comprehensive identification and quantification of resource interactions; integrating economic, environmental, and societal considerations; and ensuring theoretical rigor and empirical solvability. No existing WEF nexus model simultaneously fulfils all six objectives. To address this gap, we develop the first transparent and comprehensive WEF nexus model that achieves all six objectives. The proposed model links water quantity and quality – including pollutants and temperature – with energy and food systems to analyse system-wide water dynamics. The model explicitly represents water-energy interactions, capturing how thermoelectric generation alters water thermal regimes and, in turn, affects hydrological processes. It also accounts for human-water interactions by incorporating return flows of water after human consumption, emphasizing water circularity. The model's applicability is illustrated through an example of the Beijing-Tianjin-Hebei region in China, and its broader empirical and policy relevance is demonstrated through a set of potential scenarios. These advances provide a systems foundation for understanding hydrological science and for developing sustainable, efficient, and equitable resource strategies.
Review egusphere-2025-4663 “Towards an ideal water-energy-food nexus model: moving beyond silos to integrated resource governance”
General comments
The paper presents a purely theoretical WEF nexus model that is rigorous in theoretical development but lacking in applicability and demonstration. The claim that the model is ‘ideal’ being generally applicable is, in my opinion, overstating things substantially as there is absolutely no evidence to support the claim. This wording should be tempered considerably as the claim is not backed up. There are no results to support any such claims, nor indeed to show that the model is even functional. For this reason, I also find the claims that the ‘model’ achieves six objectives set out in the paper rather a stretch. In principle perhaps it does, but until there is empirical support, I feel the claims should be significantly reduced.
I also feel that there is no such thing as an ‘ideal’ nexus model that is generally applicable across spatial and temporal scales. Over 15 years of nexus research have taught me that for any nexus model to have any practical value beyond an academic exercise, the model must be developed contextually, and often in collaboration with local experts and stakeholders. For this reason, I again suggest that the authors temper their claims of the applicability, generalisability, and indeed usefulness of the purely theoretical mode developed in the paper. I would also suggest that the authors consider this a bit more deeply rather than overstating the ability of a model that as yet has no results to support it.
How is the model proposed to be calibrated and validated? At the moment there are no results, yet no procedure for this aspect is considered.
Although data is mentioned in one line near the end of the paper, much more should be made of the actual feasibility of applying the theoretical model developed. It contains a vast amount of parameters, some being very specific. No note is made on where data could come from, data reliability, uncertainty, or the consequences to the model as a whole if large data are not available. Again, over 15 years experience tell me that often much compromise must be made in nexus modelling efforts as a result of data constraints. Reality is far from theoretical idealism.
While I appreciate the theoretical development, the model runs the real risk of being just that – a theoretical construct with little to no practical, real-world relevance. This would only add to criticisms of the nexus.
The claim that the model was illustrated through the example of the Beijing-Tianjin-Hebei region should be removed. There is no evidence to support this claim. It is a theoretical construct only.
Specific comments
The introduction lacks any real mention of the criticisms levelled at “the nexus”. There is a wide body of literature on this topic, which should be included to give a more balanced perspective.
The term ‘ideal model’ is used throughout the paper yet never properly defined. This should be addressed.
Line 34: “a model should achieve resource security…”. No model can achieve this. It can merely suggest possible pathways towards it. Please rephrase.
Line 40: water quality in addition to temperature and heavy metals has been studied in a WEF nexus context. See Amorocho-Daza H., Sušnik J., Slinger J.H., van der Zaag P. 2026. A participatory system dynamics approach to assess transboundary nutrient pollution: modelling the water-energy-food-ecosystems nexus in the Lielupe River Basin, Lithuania and Latvia. Ecological Modelling. 513: 111417.
Line 45-46: the note on a model having to be transferable. Please see my general comment above.
Line 65: the fact that the model developed here builds on a model developed for the Jordan River seems to be in contradiction of it being generally applicable. This discrepancy needs to be addressed. For example, how could such a specific model be extended to be widely applicable across time, space, and contexts? Also, the JRB model is said to exclusively represent water, thus contradicting its ability to model nexus interactions. Does taking a water-centric model represent a good starting place for an alleged ‘ideal’ nexus model? If so why? I feel this argument is not yet made to an adequate degree
There is multiple mention on ‘pure water’, but this is not defined. Even ‘pure water’ contains nutrients, minerals, suspended material.
Food quality à what does this actually measure/mean in practice? What is/are the variables being tracked here? Food access? Cost? Nutritional value? Calories? Against what benchmark(s)? As with other variables, this need expanding to have any practical meaning. How is food quality (however measured) affected in the model?
Following from the above comment – a diagram showing causal impacts in the model would be of great value to the reader to understand nexus interactions.
Line 265: what is ‘homogeneous energy’? And as with the food comment, what is meant by energy quality? Is it access? Hours of access? Reliability? Fuel source? Cooking fuel? Source of power? How is it affected in the model?
Line 290-295, but throughout the paper: where does one get all these coefficients and fractions? How are they verified and validated? Are they done on a per-case basis? In which case the model is not generally applicable…This again represents a major data challenge.
Line 301: mention is made here of ‘cells’. So is the model an agent-based model/cellular automata? If so, this needs to be explicitly mentioned.
Line 325: What about food waste, energy waste? Are these considered? Food and energy can be lost from a system (degraded food, waste heat, transmission losses).
Line 332: ‘no resources will disappear’. This is unrealistic and should be addressed.
Line 345: e.g. reduced water quality and elevated temperature. How are these changes estimated in the model? There is a lot of ambiguity here. As mentioned above, a conceptual figure showing model interactions would significantly help. I know there are some figures like this in the appendix, but I feel some more specific examples to illustrate key processes should be included.
Line 350: the technology-specific matrix à this again alludes to my comment on the data-intensiveness of the model and how feasible it would be to implement it in any meaningful way. More must be made of this issue.
The social welfare metric is relatively poor. There are far better indicators of social progress and benefit. Why was this specific metric chosen over others? For example nothing is mentioned of equity, access, distribution, or the sustainability of consumption of finite resources.
Appendix C: how are changes in crop yield estimated?
Water-for-energy, line 598: hydropower does consume water – rather a lot. See e.g. https://www.sciencedirect.com/science/article/pii/S0960148116306176, https://onlinelibrary.wiley.com/doi/full/10.1002/gch2.201600018, and https://hess.copernicus.org/articles/17/3983/2013/ as just a few examples
Due to the nature of the comments above, no technical/typographical comments are included at this stage.