Herein, we investigated the relationship between water, food, and energy (W–E–F) in different regions of China to provide suggestions for sustainable and stable regional development of these resources. Based on the system theory, we constructed three relevant subsystems and analyzed the action mechanism between them. Furthermore, we constructed a network based on the super-efficiency data envelopment analysis model for a W–E–F input–output index system. This model was applied to 30 areas in China from the year 2005 to 2015 for measuring W–E–F coupling efficiency. We conducted a spatial correlation analysis to measure the results. This study demonstrated that the overall regional and interprovincial W–E–F coupling efficiency was low, with food subsystem as the main reason for low efficiency in the entire system and key reason for regional differences. When comparing the three subsystems, the efficiency value of the water resources subsystem showed little change over time. In 2015, the water resource efficiency in most regions reached an effective and effective marginal state. The efficiency of the energy subsystem and the food subsystem is on the rise. Overall, the food subsystem's efficiency is low, and in 2015, the food efficiency of several regions in northwest China was between 0.2–0.4 Spatial agglomeration was detected in W–E–F coupling efficiency in various regions of China. From a local spatial differentiation perspective, the proportion of the low–low (LL) space-related agglomeration pattern and high–high (HH) agglomeration was substantial. The LL agglomeration was primarily concentrated in the western and central underdeveloped areas, and a relatively stable space distribution of HH agglomeration occurred mainly in the eastern region.

The water-food nexus in the Middle East and Northern African (MENA) region is characterized by resource depletion, import dependence and environmental degradation. This contribution proposes that consumption awareness and resource circularity can be seen as a pathway to alleviate environmental problems and achieve long-term supply security in the water and food sectors. The chapter introduces wastewater recycling as a salient and highly relevant development in the MENA region. Current directions in using treated wastewater are analyzed. Furthermore, forerunner countries from different MENA sub-regions are briefly introduced with the focus on the particular characteristics and policy challenges in each of presented cases of wastewater reuse. Furthermore, crosscutting issues are presented. These include the need for addressing the large consumption footprints in MENA countries, the existence of distorting subsidies for agricultural water, the lack of communities' participation, the inadequacy of existing strategies and the suboptimal coordination mechanisms between water and food sectors. We suggest at the end of the paper some recommendations to policy makers in the region. | Scopus

The Mediterranean is an area where the balance between water demand and abstractions vs. water availability is often under stress already, as demonstrated here with the Water Exploitation Index. In this work, model estimates on how different proposed measures for water resources management would affect different indicators. After a review of the current water resources status in the Mediterranean and the definition of indicators used in this study, aspects interlinked with water in the Water-Energy-Food-Ecosystems Nexus are briefly discussed, focusing on problems linked with water scarcity and depletion of groundwater resources as well as with climate change projections. Subsequently, the proposed measures for water efficiency are detailed—irrigation efficiency, urban water efficiency, water reuse and desalination—that might be effective to reduce the growing water scarcity problems in the Mediterranean. Their effects that result from the LISFLOOD model, show that wastewater reuse, desalination and water supply leakage reduction lead to decreased abstractions, but do not affect net water consumption. Increased irrigation efficiency does decrease consumption and reduces abstractions as well. We deduct however that the current envisaged water efficiency measures might not be sufficient to keep up with the pace of diminishing water availability due to climate change. More ambition is needed on water efficiency in the Mediterranean to keep water scarcity at bay.

The Water-Energy-Food (WEF) nexus approach should be promoted as a tool for sustainable management of resources through the interconnection of these three fundamental pillars. Particularly, food security must ensure healthy and balanced diets for everyone, but selecting individual indicators to assess all slants covered by this element is not an easy task. Hence, the objective of this paper is two-fold, to review nutrient profiling (NP) models that allow to categorize foods and evaluate diets based on their nutritional quality, and to choose the most appropriate model to be used within a WEF nexus index. To address this issue, a total of 159 documents were assessed, appraising the geographic distribution, and time evolution of the publications, as well as the characteristics and potential applications of the NP systems. The review concludes that the NRF9.3. model is the most liable option to be used in a WEF nexus index, presenting the best characteristics by means of the definition of scores and thresholds, and the use of an 'across-the-board' criteria and a reference quantity of 100 kcal, alongside offering higher ability to assess diets and foods than the other competitive model (HEI) through the evaluation of nutrients to encourage instead of foods. A secondary outcome of the review is the identification of the NP models as a useful tool to enable institutions with information to establish policies in the field of public health and facilitating the decision-making process according to the current healthy claims | The authors are grateful for the funding of the Spanish Ministry of Science and Innovation through the KAIROS-BIOCIR project (PID2019-104925RB) (AEO/FEDER, UE) and of the Interreg Atlantic Area through the NEPTUNUS project (EAPA_576/2018). Daniel Hoehn thanks the Ministry of Economy and Competitiveness of Spanish Government for their financial support via the research fellowship BES-2017-080296. Jorge Cristóbal acknowledges financial support from the Spanish Ministry of Science, Innovation and Universities through the “Beatriz Galindo” grant BEAGAL18/00035.

The Water-Energy-Food (WEF) nexus approach should be promoted as a tool for sustainable management of resources through the interconnection of these three fundamental pillars. Particularly, food security must ensure healthy and balanced diets for everyone, but selecting individual indicators to assess all slants covered by this element is not an easy task. Hence, the objective of this paper is two-fold, to review nutrient profiling (NP) models that allow to categorize foods and evaluate diets based on their nutritional quality, and to choose the most appropriate model to be used within a WEF nexus index. To address this issue, a total of 159 documents were assessed, appraising the geographic distribution, and time evolution of the publications, as well as the characteristics and potential applications of the NP systems. The review concludes that the NRF9.3. model is the most liable option to be used in a WEF nexus index, presenting the best characteristics by means of the definition of scores and thresholds, and the use of an ‘across-the-board’ criteria and a reference quantity of 100 kcal, alongside offering higher ability to assess diets and foods than the other competitive model (HEI) through the evaluation of nutrients to encourage instead of foods. A secondary outcome of the review is the identification of the NP models as a useful tool to enable institutions with information to establish policies in the field of public health and facilitating the decision-making process according to the current healthy claims.

Water-Energy-Food (WEF) Nexus and CO2 emissions for a farm in northwest Iran were analyzed to provide data support for decision-makers formulating national strategies in response to climate change. In the analysis, input–output energy in the production of seven crop species (alfalfa, barley, silage corn, potato, rapeseed, sugar beet, and wheat) was determined using six indicators, water, and energy consumption, mass productivity, and economic productivity. WEF Nexus index (WEFNI), calculated based on these indicators, showed the highest (best) value for silage corn and the lowest for potato. Nitrogen fertilizer and diesel fuel with an average of 36.8% and 30.6% of total input energy were the greatest contributors to energy demand. Because of the direct relationship between energy consumption and CO2 emissions, potato cropping, with the highest energy consumption, had the highest CO2 emissions with a value of 5166 kg CO2eq ha−1. A comparison of energy inputs and CO2 emissions revealed a direct relationship between input energy and global warming potential. A 1 MJ increase in input energy increased CO2 emissions by 0.047, 0.049, 0.047, 0.054, 0.046, 0.046, and 0.047 kg ha−1 for alfalfa, barley, silage corn, potato, rapeseed, sugar beet, and wheat, respectively. Optimization assessments to identify the optimal cultivation pattern, with emphasis on maximized WEFNI and minimized CO2 emissions, showed that barley, rapeseed, silage corn, and wheat performed best under the conditions studied. | publishedVersion

The efficacy of electrolyzed water (EW) to inactivate Listeria monocytogenes on stainless steel surfaces was evaluated and modelled in the present study. L. monocytogenes was inoculated on stainless steel coupons and subsequently subjected to Neutral EW (NEW, pH = 7.0) and Slightly Acid EW (SAEW, pH = 5.0) with different Available Chlorine Concentration (ACC, 50–200 mg/L) for different exposure times (0–6 min). The number of viable cells on coupons decreased as the exposure time increased at all ACC concentrations. Treatments with SAEW resulted in higher reductions of L. monocytogenes, i.e., 2.30 ± 0.16 to 5.64 ± 0.11 log cfu/cm², in comparison with NEW treatments (1.55 ± 0.11 to 5.22 ± 0.12 log cfu/cm²), probably due to the synergistic bactericidal effect between the acidic pH, higher oxidation-reduction potential and the effective form of chlorine, reported in previous studies. Since SAEW was the most effective against L. monocytogenes, two approaches were tested to model the survival data: the one- and two-step modelling procedures. The Weibull model was suitable to describe the survival data and both approaches produced suitable survival models (adj-R²>0.92 and MSE<0.2). EW is effective in reducing bacterial contamination on food-contact surfaces and the survival data and models derived from this study are relevant to optimize its use as an environment-friendly sanitizer in the food industry.

A key challenge for sustainability is protecting water-related ecosystems and the services (WESs) they provide while enhancing food security. Food production usually drives land use change, which results in ecosystem services provision being altered. However, the underlying mechanisms are still unclear and relevant research is scarce. In this study, a spatio-temporal assessment framework was developed to assess the impact of food production-driven land use change on WESs and to analyze tradeoffs between food production and WESs provision, taking Songhua River Basin (SRB) as a case study. The results showed that: 1) food production increased from 0.497×108tons to 0.798×108tons despite area of cultivated land decreasing from 23.61×104km2 to 23.40×104km2 during the study period (2000–2015). 2) Water yield and soil retention both showed a downward trend, while nitrogen and phosphorus exports showed an increasing trend, in 2000–2015.3) Food production showed a trade-off relationship with soil retention and water yield, but a synergistic relationship with nitrogen and phosphorus export. This is important empirical evidence of the impact of food production-driven land use change on WESs. For simultaneous development of food production and WESs, a form of sustainable agricultural production must be established, with intensification of existing land use and establishment of farmland shelterbelts. This critical knowledge can be applied in developing practical ecosystem protection measures and land management strategies for food security in China and beyond.

Demands for water, food, and energy are rising owing to increasing population and growing economy. Agriculture is the main source of food and is the largest consumer of water and has therefore the greatest impact on water security. It also greatly affects energy security and is also the main source of non-point source pollution. Changes in the availability of water, energy, and land are driven by uncertainties in nature and strongly affect food production, with severe implications for the security of water–food–energy nexus (WFEN). Thus, a coordinated and effective management of WFEN in the agricultural sector is needed. This paper therefore proposes an integrated modelling approach for the optimization of agricultural WFEN in a random environment. The approach quantifies the interactions and feedbacks within agricultural water, food and energy subsystems, making tradeoffs between agricultural benefit and environmental impacts, which will serve as sustainability indicators for agricultural systems, including crop farming and livestock farming. The incorporation of stochastic mathematical programming in the modeling framework aids in understanding how strategies and comprehensive benefits change under different scenarios. The approach was applied in a real-world case study in an irrigation district in northeast China. The development and implementation of such an integrated approach are anticipated to be applied in other agriculture-centered regions to guide policies of sustainable water, food, energy and land resources management.

Water security is a powerful concept that is still in its early days in the field of nutrition. Given the prevalence and severity of water issues and the many interconnections between water and nutrition, we argue that water security deserves attention commensurate with its importance to human nutrition and health. To this end, we first give a brief introduction to water insecurity and discuss its conceptualization in terms of availability, access, use, and stability. We then lay out the empirical grounding for its assessment. Parallels to the food-security literature are drawn throughout, both because the concepts are analogous and food security is familiar to the nutrition community. Specifically, we review the evolution of scales to measure water and food security and compare select characteristics. We then review the burgeoning evidence for the causes and consequences of water insecurity and conclude with 4 recommendations: 1) collect more water-insecurity data (i.e., on prevalence, causes, consequences, and intervention impacts); 2) collect better data on water insecurity (i.e., measure it concurrently with food security and other nutritional indicators, measure intrahousehold variation, and establish baseline indicators of both water and nutrition before interventions are implemented); 3) consider food and water issues jointly in policy and practice (e.g., establish linkages and possibilities for joint interventions, recognize the environmental footprint of nutritional guidelines, strengthen the nutrition sensitivity of water-management practices, and use experience-based scales for improving governance and regulation across food and water systems); and 4) make findings easily available so that they can be used by the media, community organizations, and other scientists for advocacy and in governance (e.g., tracking progress towards development goals and holding implementers accountable). As recognition of the importance of water security grows, we hope that so too will the prioritization of water in nutrition research, funding, and policy. © 2021 The Author(s) 2021. Published by Oxford University Press on behalf of the American Society for Nutrition.