By 2050, the global Earth population will reach 10 billion, leading to increased water, food, and energy needs. Availability of water in sufficient quantities and appropriate quality is a prerequisite for human societies and natural ecosystems. In many parts of the world, excessive water consumption and pollution by human activities put enormous pressure on this availability as well as on food and energy security, environmental quality, economic development, and social well-being. Water, food/materials, and energy are strongly interlinked, and the choices made in one area often have consequences on the others. This is commonly referred to as the “water-food-energy” nexus. These interconnections intensify as the demand for resources increases with population growth and changing consumption patterns, and Humanity continues using a linear economy model of ‘take-make-dispose’. The nexus makes it difficult for governments, public and private organizations, and the public, to set and follow a clear path towards a sustainable economy i.e., “meeting the needs of the present without compromising the ability of future generations to meet their own needs”. Humanity best chance at mitigating climate change, and shortage of resources is to harness the value of water as much as possible.This paper reviews the latest publications about the water-food-energy nexus and climate change, putting numbers into perspective, attempting to explain why water circularity is part of the key factors to accelerate the transition from a linear economy to a circular economy, and to meet the UN Sustainable Development Goals, and how circularity can be implemented in the water sector.

Today, scientific research on the types of Nexus, especially the water- energy- food Nexus as the driver of improving the welfare of society, is expanding. Since the Nexus approach is relatively new and requires the cooperation of several fields, explaining the concepts, its literature review, with a special focus on the water- energy- food Nexus is essential. This article aims to express Nexus approach simple and clear, by a detailed review of several related articles from 2011 to 2021. Articles were reviewed and categorized by year, source variety, and topic. So the outline of the formation of the Nexus approach, water- energy- food Nexus and the questions raised about this approach were codified in a way that provides a practical insight for policy making. In general, the Nexus approach, especially the water- energy- food Nexus which creates a very complex system and must be considered from a political, social and economic perspective, is difficult to implement. However, the Nexus approach is transitioning to an important component of development planning, and its success requires the guidance of strategic policies and institutional structures in multilevel governance. It seems that countries need to reform their governance structures in line with the Nexus approach. Another issue that has been considered in this article is the difference between the Water- Energy- Food Nexus approach with the approach of integrated water resources management. Due to the similarities, there are doubts about the need to move from integrated water resources management to Water- Energy- Food Nexus.

By 2050, the global Earth population will reach 10 billion, leading to increased water, food, and energy needs. Availability of water in sufficient quantities and appropriate quality is a prerequisite for human societies and natural ecosystems. In many parts of the world, excessive water consumption and pollution by human activities put enormous pressure on this availability as well as on food and energy security, environmental quality, economic development, and social well-being. Water, food/materials, and energy are strongly interlinked, and the choices made in one area often have consequences on the others. This is commonly referred to as the “water-food-energy” nexus. These interconnections intensify as the demand for resources increases with population growth and changing consumption patterns, and Humanity continues using a linear economy model of ‘take-make-dispose’. The nexus makes it difficult for governments, public and private organizations, and the public, to set and follow a clear path towards a sustainable economy i.e., “meeting the needs of the present without compromising the ability of future generations to meet their own needs”. Humanity best chance at mitigating climate change, and shortage of resources is to harness the value of water as much as possible. This paper reviews the latest publications about the water-food-energy nexus and climate change, putting numbers into perspective, attempting to explain why water circularity is part of the key factors to accelerate the transition from a linear economy to a circular economy, and to meet the UN Sustainable Development Goals, and how circularity can be implemented in the water sector.

Water competition is a key issue in the study of the water-food-energy nexus (WFEN), which can affect water, food, and energy security and can generate notable challenges in water resource management. Since Bayesian network can express parameter uncertainty with a certain probability distribution while reflecting the dependencies of each variable, this study used a Bayesian network to model the WFEN in the Pearl River Region (PRR). The network structure can intuitively represent complex causal relationships, and the form of the probability distribution can effectively reflect the variable uncertainty. The responses of the Bayesian network model under different scenarios were used to analyse the major influencing factors, and water competition relationships in various sectors were explored. The results indicated that water competition between the different sectors was very complex and could dynamically change under the different scenarios. For example, an increase in hydropower and flow to sea could lead to a decrease in irrigation water, but an increase in irrigation water did not necessarily reduce hydropower and flow to sea. Water for hydropower generation and salt tide alleviation were obviously affected by the total offstream water use, but there existed no obvious water competition between these aspects in general. However, when offstream water use remained stable, a competitive relationship was observed between hydropower and flow to sea. Overall, the outcomes of this study could be of great significance to further analyse the WFEN in other regions.

Abstract Efficient use of water and energy is crucial in food processing. One of the major problems in the food processing is the creation of food waste. Reducing food waste is essential to fill the global food gap and help reduce water and energy gaps around the world. Also, efficient use of water and energy in food processing is crucial. Examining scientific sources, it seems that Nexus thinking can be considered as the key to reducing food waste. Proper planning and management of limited water, energy, and food resources to meet society's economic and social needs for sustainable development is always a challenging issue. In this paper, considering the two thermal power plants with coal fuel and natural gas fuel in Baghdad, the relationship between food production, water consumption, energy production, and CO2 emissions has been investigated. Considering three periods (5 years) and estimating demand and forecasting energy and food production, Nexus has been studied between water, food, and energy parameters. During these three periods, the amount of natural gas consumption has increased by 13.13%, 25.7%, and 28.79% compared to the total energy. Also, in the optimal case, the cost of the system is $ 5.65 billion.

Chlorogenic acid (CQA), the ester of caffeic acid with quinic acid, has been one of the most studied polyphenols due to its potential biological activity and usefulness in pharmaceutical treatment. We found that in an aqueous solution of each chlorogenic acid isomer, 3-, 4- and 5-CQA, its two complexes with water are formed. In the RP chromatographic system, these CQA-water derivatives differ in retention data from that of their precursors and do not decompose, which indicates their considerable stability. The formation of CQA-water complexes has not been reported yet. Comprehensive NMR research of CQA-water derivatives complexes shows that their significant stability results from the formation of hydrogen bonds between water and CQA isomer – e.g., between water and OH3, OH4 and ester groups of CQA molecule in the case of 5-CQA-water derivative. The existence of CQA-water derivatives in CQA containing food products was in the paper shown. It should be noted that the stable CQA-water complexes may exhibit a different biological activity than CQA. This issue requires separate biomedical research.

Establishing cooperation in transboundary rivers is challenging especially with the weak or non-existent river basin institutions. A nexus-based approach is developed to explore cooperation opportunities in transboundary river basins while considering system operation and coordination under uncertain hydrologic river regimes. The proposed approach is applied to the Nile river basin with a special focus on the Grand Ethiopian Renaissance Dam (GERD), assuming two possible governance positions: with or without cooperation. A cooperation mechanism is developed to allocate additional releases from the GERD when necessary, while a unilateral position assumes that the GERD is operated to maximize hydropower generation regardless of downstream users' needs. The GERD operation modes were analysed considering operation of downstream reservoirs and varying demands in Egypt. Results show that average basin-wide hydropower generation is likely to increase by about 547 GWh/year (1%) if cooperation is adopted when compared to the unilateral position. In Sudan, hydropower generation and water supply are expected to enhance in the unilateral position and would improve further with cooperation. Furthermore, elevated low flows by the GERD are likely to improve the WFE nexus outcomes in Egypt under full cooperation governance scenario with a small reduction in GERD hydropower generation (2,000 GWh/year (19%)). HIGHLIGHTS Water-Food-Energy Nexus framework is applied to explore cooperation opportunities in shared rivers.; Cooperation is likely to increase total average hydropower generation compared to the unilateral mode.; Downstream drought-related risks could be reduced with negligible impacts on upstream objectives if countries agree to share the risk.; A high level of coordination among countries is required to achieve the cooperation benefits.;

Ensuring resilient food systems and sustainable healthy diets for all requires much higher water use, however, water resources are finite, geographically dispersed, volatile under climate change, and required for other vital functions including ecosystems and the services they provide. Good governance for resilient water resources is a necessary precursor to deciding on solutions, sourcing finance, and delivering infrastructure. Six attributes that together provide a foundation for good governance to reduce future water risks to food systems are proposed. These attributes dovetail in their dual focus on incorporating adaptive learning and new knowledge, and adopting the types of governance systems required for water resilient food systems. The attributes are also founded in the need to greater recognise the role natural, healthy ecosystems play in food systems. The attributes are listed below and are grounded in scientific evidence and the diverse collective experience and expertise of stakeholders working across the science-policy interface: Adopting interconnected systems thinking that embraces the complexity of how we produce, distribute, and add value to food including harnessing the experience and expertise of stakeholders s; adopting multi-level inclusive governance and supporting inclusive participation; enabling continual innovation, new knowledge and learning, and information dissemination; incorporating diversity and redundancy for resilience to shocks; ensuring system preparedness to shocks; and planning for the long term. This will require food and water systems to pro-actively work together toward a socially and environmentally just space that considers the water and food needs of people, the ecosystems that underpin our food systems, and broader energy and equity concerns. | PR | 1 Fostering Climate-Resilient and Sustainable Food Supply; IFPRI3 | EPTD

Water, energy and food are three essential resources for the socio-economic system, and they are interlinked. The coordination of their internal relations is worth studying. We conduct a coordination evaluation method to assess the water-energy-food nexus (WEF Nexus) in China’s provinces. By combining the coupling model and the coupling coordination model, we measure the comprehensive evaluation index and coupling coordination degree of China’s 30 provinces from 2005 to 2017. First, the results show the provincial comprehensive evaluation index had a slow upward trend. The comprehensive evaluation index of the southern region was higher than that of the north, and the eastern was higher than the west. Second, the coordination degree of WEF Nexus in China’s 30 provinces has reached high level in the horizontal coupling stage, and the overall degree of coupling coordination was on the rise. In 2017, the WEF Nexus coupling coordination degree of most provinces reached 0.700 or more, which was intermediate-coordinated. In the six years, the 30 provinces have experienced five types of coupling coordination degree: near coordinated, barely coordinated, primary coordinated, intermediate-coordinated, and well-coordinated.