China’s water resources are under increasing pressure from socioeconomic development, diet shifts, and climate change. Agriculture still concentrates most of the national water withdrawal. Moreover, a spatial mismatch in water and arable land availability—with abundant agricultural land and little water resources in the north—increases water scarcity and results in virtual water transfers from drier to wetter regions through agricultural trade. We use a general equilibrium welfare model and linear programming optimization to model interprovincial food trade in China. We combine these trade flows with province-level estimates of commodities’ virtual water content to build China’s domestic and foreign virtual water trade network. We observe large variations in agricultural water-use efficiency among provinces. In addition, some provinces particularly rely on irrigation vs. rainwater. We analyze the virtual water flow patterns and the corresponding water savings. We find that this interprovincial network is highly connected and the flow distribution is relatively homogeneous. A significant share of water flows is from international imports (20%), which are dominated by soy (93%). We find that China’s domestic food trade is efficient in terms of rainwater but inefficient regarding irrigation, meaning that dry, irrigation-intensive provinces tend to export to wetter, less irrigation-intensive ones. Importantly, when incorporating foreign imports, China’s soy trade switches from an inefficient system to a particularly efficient one for saving water resources (20 km ³/y irrigation water savings, 41 km ³/y total). Finally, we identify specific provinces (e.g., Inner Mongolia) and products (e.g., corn) that show high potential for irrigation productivity improvements.

Many countries are exposed to malnutrition within their population, either in the form of undernutrition or obesity leading to dire affects for human health. As a consequence, a ‘Decade of Action’ was certified by the UN in 2016 to promote the need to end all types of malnutrition. Within food security objectives, this study evaluates the possibility to maximise the nutritional value of agricultural output through the optimal allocation of water and energy resources. Using a hypothetical case study in Qatar, two complementary multi-objective mathematical models are developed to solve various scenarios. Firstly, the goal programming minimises the expected value of negative deviation from the desired target in food groups and nutrients. Secondly, the linear programming model increases the expected value of self-sufficiency percentage in food groups and nutrients. The results indicate the specific dependency of increasing the self-sufficiency of different nutrients on the increased production of dates group and fish group, implying that dates and fish can be considered strategic crops in terms of their contribution towards food security, owing to the fact that they require the least quantity of water and energy resources for production. As poultry and meat groups require the largest quantities of water and energy resources, optimal results do not favour their production. The optimal production mix that increases the satisfaction of nutrients at 40% of the food groups self-sufficiency satisfaction with the same amount of energy and water are as follows: 52378, 47085, 111303 tonnes of dates, milk and dairy products and fish groups respectively. This production mix will achieve 29.18%, 100%, 90.8%, and 2.5% satisfaction percentage of carbohydrates, protein, fats, and fibres respectively.

The issue of  water resources using which make the best using  stayed one of the most important issue  which Egyptian society suffer from on the two levels  individual  and national .  The research depended for a achieving his goals on the discriptive and statistical method which representative on linear programmar method and the researcher depended on the data which be published by research associations such as the central agency for the general mobilization and statistics and ministry of agriculture and  reclaimation the lands.  The research showed that the limitations of crops combination are (the agricultural land – the water resources) and the constraints which be used in linear programmar model are (crops area- feddan return net) and by the looking for the   actual crops combination we can observe that it consist of (42 crops divided into (17 winter crops – 13 summer crops- 6 nile  crops- 6 fruits) and from the research results showed that the gross water amount was (46271.5) million m3 and the water amount for the winter crops was (14870.7) million m3 and the water amount for the summer crops was (23552.6) million m3 whereas the nile crops was (1041) million m3 and the fruits was (6807.2) million m3 and which related to the crops area the results showed that the gross area was (13678254.7) feddan and the winter crops was (6613977.2) feddan whereas the summer crops was (5325536.7) feddan and the nile crops was (392740.8) and which related to the fruits was (1246000) feddan

Massive amounts of water and land embodied in crops are transferred via food trade. This study established a network-based framework for the water–land nexus in food trade to investigate the spatial linkages of water, land, and food. Based on the gravity model and linear programming optimization, the food trade model was first built to simulate crop trade. Then water consumption and land use for various crops in different regions were inventoried to establish the food-related virtual water network and food-related virtual land network. Grey water related to water quality, blue and green water related to water quantity, were incorporated into the food-related virtual water accounting framework to identify the role of food trade in the spatial reallocation of water. Similarly, the food-related virtual land network was built based on the land use for different crops and the food trade model. Finally, a case study was conducted using ecological network analysis to analyze the properties and connections within the food-related virtual water/land networks of China. The results showed that the green and grey water consumption associated with food production, the effects of which have previously been neglected, account for a huge proportion of the total water consumption, especially in water-scarce provinces. The controllers/dependents in the networks that have strong control relationships with other provinces were identified. The proposed network-based framework for the water–land nexus may help boost synergies associated with spatial reallocation of water and land via food trade and explore pathways for sustainable management of water, land, and food resources.

Activities in the food-energy-water nexus require ecosystem services to maintain productivity and prevent ecological degradation. This work applies techno-ecological synergy concepts in an optimization formulation to design a system for co-producing food and energy under constraints on ecological sustainability. The system includes land use activities and biomass conversion processes for the production of energy carriers, as well as supporting ecosystems that increase the supply of key ecosystem services. The co-production system was linearized and reduced to a mixed-integer linear program, which was optimized for single objectives under a variety of production and sustainability constraints. Results indicate that for the system considered to achieve high food and energy co-production, land use options should be balanced between food-producing crops and electricity-producing wind turbines and solar panels. Results also show that ecological sustainability can be achieved for this system with relatively small changes in land use patterns. The inclusion of nature in the design enables the system as a whole to achieve ecological sustainability for multiple ecosystem services with moderate sacrifices of food and energy productivity.

Since the Bonn 2011 Conference, the Food-Energy-Water (FEW) nexus has become one of the most popular global research topics. Understanding and addressing the complex interactions between the FEW components is essential for sustainable development. This study proposes an environmental impact minimization model, which considers the FEW nexus under four climate change scenarios, to optimize the spatial distribution of three energy crops (rice, corn, and sugarcane). Life cycle assessment (LCA), linear programming, and a climate change simulation model are integrated to analyze appropriate bioenergy production rates while comparing the benefits of bioenergy with the current renewable energy policy in Taiwan. The major findings of LCA in this study indicate that electricity generation using bio-coal produced from rice straw is very beneficial to the environment. Considering the spatial characteristics of Taiwan, simulations from the spatial optimization model suggested that (a) the rice and corn cultivation areas should be increased in southern Taiwan for bio-coal and bioethanol production, in accordance with the “food and feed priority policy”; and (b) the rice cultivation area should be decreased across Taiwan, based on the “water conservation policy”. In addition, compared to solar power, the development of bioenergy can simultaneously enhance food and energy self-sufficiency.

The energy-water nexus is a concept widely established but rarely applied to product and, in particular, to food and beverage products, which have a great influence on greenhouse gases emissions. The proposed method considers the main nexus aspects in addition to other relevant aspects such as climate change, which is deeply linked with energy and water systems, and assessing process as well as product. In this framework, this study develops an integrated index (IWECN) that combines life cycle assessment (LCA) and linear programming (LP) to assess energetic, water and climate systems, enabling the identification of those products with minors energetic and water intensity and climate change effects and helping to the decision-making process and to the development of eco-innovation measures. In this case, the product assessed was one bottle (70 cl) of gin and two main hotspots were identified: the production of the glass bottle and the energy requirements of the distillation stage. Based on that, several eco-innovation strategies were proposed: the use of photovoltaic solar energy as energy source and the substitution of the glass bottle by a plastic one and by a tetra brick. The nexus results indicated that the use of solar photovoltaic energy and plastic as bottle material was the best alternative decreasing 58% the IWECN value of the production of one bottle of gin. The sensitivity analysis presented a strong preference for photovoltaic solar energy in comparison with electric power and for the reduction of the glass bottle weight or its substitution by a plastic bottle. The use of the IWECN index is extendable to any product with the aim of facilitating the decision-making process in the development of more sustainable products to introduce them in new green markets.

The energy-water nexus is a concept widely established but rarely applied to product and, in particular, to food and beverage products, which have a great influence on greenhouse gases emissions. The proposed method considers the main nexus aspects in addition to other relevant aspects such as climate change, which is deeply linked with energy and water systems, and assessing process as well as product. In this framework, this study develops an integrated index (IWECN) that combines life cycle assessment (LCA) and linear programming (LP) to assess energetic, water and climate systems, enabling the identification of those products with minors energetic and water intensity and climate change effects and helping to the decision-making process and to the development of eco-innovation measures. In this case, the product assessed was one bottle (70 cl) of gin and two main hotspots were identified: the production of the glass bottle and the energy requirements of the distillation stage. Based on that, several eco-innovation strategies were proposed: the use of photovoltaic solar energy as energy source and the substitution of the glass bottle by a plastic one and by a tetra brick. The nexus results indicated that the use of solar photovoltaic energy and plastic as bottle material was the best alternative decreasing 58% the IWECN value of the production of one bottle of gin. The sensitivity analysis presented a strong preference for photovoltaic solar energy in comparison with electric power and for the reduction of the glass bottle weight or its substitution by a plastic bottle. The use of the IWECN index is extendable to any product with the aim of facilitating the decision-making process in the development of more sustainable products to introduce them in new green markets. | Rubén Leivas thanks the Industrial Doctorates Program of the Cantabria University, the Santander Bank and the Ministry of Education, Culture and Sport by means of the Campus of International Excellence Program for the financial support. Jara Laso thanks the University of Cantabria for its financial support via the postdoctoral grant “Augusto Gonzalez Linares”. The authors are grateful for the funding of the Spanish Ministry of Economy and Competitiveness through the Ceres-Procom: Food production and consumption strategies for climate change mitigation (CTM2016-76176-C2-1-R).

While the water–energy–food nexus approach is becoming increasingly important for more efficient resource utilization and economic development, limited quantitative tools are available to incorporate the approach in decision-making. We propose a spatially explicit framework that couples two well-established water and power system models to develop a decision support tool combining multiple nexus objectives in a linear objective function. To demonstrate our framework, we compare eight Nepalese power development scenarios based on five nexus objectives: minimization of power deficit, maintenance of water availability for irrigation to support food self-sufficiency, reduction in flood risk, maintenance of environmental flows, and maximization of power export. The deterministic multi-objective optimization model is spatially resolved to enable realistic representation of the nexus linkages and accounts for power transmission constraints using an optimal power flow approach. Basin inflows, hydropower plant specifications, reservoir characteristics, reservoir rules, irrigation water demand, environmental flow requirements, power demand, and transmission line properties are provided as model inputs. The trade-offs and synergies among these objectives were visualized for each scenario under multiple environmental flow and power demand requirements. Spatially disaggregated model outputs allowed for the comparison of scenarios not only based on fulfillment of nexus objectives but also scenario compatibility with existing infrastructure, supporting the identification of projects that enhance overall system efficiency. Though the model is applied to the Nepalese nexus from a power development perspective here, it can be extended and adapted for other problems.

While the water–energy–food nexus approach is becoming increasingly important for more efficient resource utilization and economic development, limited quantitative tools are available to incorporate the approach in decision-making. We propose a spatially explicit framework that couples two well-established water and power system models to develop a decision support tool combining multiple nexus objectives in a linear objective function. To demonstrate our framework, we compare eight Nepalese power development scenarios based on five nexus objectives: minimization of power deficit, maintenance of water availability for irrigation to support food self-sufficiency, reduction in flood risk, maintenance of environmental flows, and maximization of power export. The deterministic multi-objective optimization model is spatially resolved to enable realistic representation of the nexus linkages and accounts for power transmission constraints using an optimal power flow approach. Basin inflows, hydropower plant specifications, reservoir characteristics, reservoir rules, irrigation water demand, environmental flow requirements, power demand, and transmission line properties are provided as model inputs. The trade-offs and synergies among these objectives were visualized for each scenario under multiple environmental flow and power demand requirements. Spatially disaggregated model outputs allowed for the comparison of scenarios not only based on fulfillment of nexus objectives but also scenario compatibility with existing infrastructure, supporting the identification of projects that enhance overall system efficiency. Though the model is applied to the Nepalese nexus from a power development perspective here, it can be extended and adapted for other problems.