Complex feedback mechanisms and interdependencies exist among the water&ndash:energy&ndash:food&ndash:ecosystems (WEFE) nexus. In water-scarce regions, fluctuations in the supply or demand of any single subsystem can destabilize the others, with water shortages intensifying conflicts among food production, energy consumption, and ecological sustainability. Balancing the synergies and trade-offs within the WEFE system is therefore essential for achieving sustainable development. This study adopts the natural&ndash:social water cycle as the core process and develops a coupled simulation model of the WEFE (CSM-WEFE) system, integrating food production, ecological water replenishment, and energy consumption associated with water supply and use. Based on three performance indices&mdash:reliability, coupling coordination degree, and equilibrium&mdash:a coordinated sustainable development index (CSD) is constructed to quantify the performance of WEFE system under different scenarios. An integrated evaluation framework combining the CSM-WEFE and the CSD index is then proposed to assess the sustainability of WEFE systems. The framework is applied to the Beijing&ndash:Tianjin&ndash:Hebei (BTH) region, a representative water-scarce area in China. Results reveal that the current balance between water supply and socio-economic demand in the BTH region relies heavily on excessive groundwater extraction and the appropriation of ecological water resources. Pursuing food security goals further exacerbates groundwater overexploitation and ecological degradation, thereby undermining system coordination. In contrast, limiting groundwater use improves ecological conditions but increases regional water scarcity and reduces food self-sufficiency. Even with the full operation of the South-to-North Water Diversion Project (Middle Route), the region still experiences a 16.4% water shortage. By integrating the CSM-WEFE model with the CSD evaluation approach, the proposed framework not only provides a robust tool for assessing WEFE system sustainability but also offers practical guidance for alleviating water shortages, enhancing food security, and improving ecological health in water-scarce regions.

Complex feedback mechanisms and interdependencies exist among the water–energy–food–ecosystems (WEFE) nexus. In water-scarce regions, fluctuations in the supply or demand of any single subsystem can destabilize the others, with water shortages intensifying conflicts among food production, energy consumption, and ecological sustainability. Balancing the synergies and trade-offs within the WEFE system is therefore essential for achieving sustainable development. This study adopts the natural–social water cycle as the core process and develops a coupled simulation model of the WEFE (CSM-WEFE) system, integrating food production, ecological water replenishment, and energy consumption associated with water supply and use. Based on three performance indices—reliability, coupling coordination degree, and equilibrium—a coordinated sustainable development index (CSD) is constructed to quantify the performance of WEFE system under different scenarios. An integrated evaluation framework combining the CSM-WEFE and the CSD index is then proposed to assess the sustainability of WEFE systems. The framework is applied to the Beijing–Tianjin–Hebei (BTH) region, a representative water-scarce area in China. Results reveal that the current balance between water supply and socio-economic demand in the BTH region relies heavily on excessive groundwater extraction and the appropriation of ecological water resources. Pursuing food security goals further exacerbates groundwater overexploitation and ecological degradation, thereby undermining system coordination. In contrast, limiting groundwater use improves ecological conditions but increases regional water scarcity and reduces food self-sufficiency. Even with the full operation of the South-to-North Water Diversion Project (Middle Route), the region still experiences a 16.4% water shortage. By integrating the CSM-WEFE model with the CSD evaluation approach, the proposed framework not only provides a robust tool for assessing WEFE system sustainability but also offers practical guidance for alleviating water shortages, enhancing food security, and improving ecological health in water-scarce regions.

The exchange of food commodities significantly contributes to alleviating the strain on land used for agricultural production by linking areas rich in land with those facing resource limitations. This study employs the entropy weight&ndash:TOPSIS method to measure the water&ndash:land&ndash:food system, utilizes a two-way fixed-effects model to examine the impact of food import competition on the coordination of the water&ndash:land&ndash:food system, and applies a spatial Durbin model to explore the spatial spillover effects of this impact. The findings indicate the following: (1) The average coordination level of the WLF system in China stands at 0.317, showing considerable variability. The WLF system coordination in all regions of China initially decreased and then increased in the period studied, with the northeast region exhibiting the highest level of coordination. (2) The competitive effect of domestic and foreign food costs driven by food imports has a positive impact on the coordination of the WLF system. For every 100,000 hectares of land saved through the competition effect, the coordination of China&rsquo:s WLF system increases by 0.002. However, once the saved land exceeds 1.5 million hectares, the impact of import competition on the importing country&rsquo:s food market becomes excessive and starts to have a negative effect. (3) Split-sample regression revealed that the positive effect of food import competition on the coordination of the WLF system is stronger in the southern region compared to the northern region. Additionally, the increase in the competition effect has a more pronounced impact on the coordination of the WLF system in major food production areas than in non-major production areas. (4) Based on the results of the spatial econometric model, the increase in the competitive effect of food imports in a region not only increases the coordination of the WLF system within that region but also positively impacts the coordination of the system in neighboring regions. (5) The land use efficiency of food imports acts as a conduit for the impact of food import competition on the coordination of the WLF system.

The exchange of food commodities significantly contributes to alleviating the strain on land used for agricultural production by linking areas rich in land with those facing resource limitations. This study employs the entropy weight–TOPSIS method to measure the water–land–food system, utilizes a two-way fixed-effects model to examine the impact of food import competition on the coordination of the water–land–food system, and applies a spatial Durbin model to explore the spatial spillover effects of this impact. The findings indicate the following: (1) The average coordination level of the WLF system in China stands at 0.317, showing considerable variability. The WLF system coordination in all regions of China initially decreased and then increased in the period studied, with the northeast region exhibiting the highest level of coordination. (2) The competitive effect of domestic and foreign food costs driven by food imports has a positive impact on the coordination of the WLF system. For every 100,000 hectares of land saved through the competition effect, the coordination of China’s WLF system increases by 0.002. However, once the saved land exceeds 1.5 million hectares, the impact of import competition on the importing country’s food market becomes excessive and starts to have a negative effect. (3) Split-sample regression revealed that the positive effect of food import competition on the coordination of the WLF system is stronger in the southern region compared to the northern region. Additionally, the increase in the competition effect has a more pronounced impact on the coordination of the WLF system in major food production areas than in non-major production areas. (4) Based on the results of the spatial econometric model, the increase in the competitive effect of food imports in a region not only increases the coordination of the WLF system within that region but also positively impacts the coordination of the system in neighboring regions. (5) The land use efficiency of food imports acts as a conduit for the impact of food import competition on the coordination of the WLF system.

The water–energy–land–food (WELF) nexus is an established framework that allows for a more holistic, systemic and integrated analysis of resources and territorial planning. The main objective of this study was to apply the WELF nexus approach to assess the environmental impacts from coal mining. Data on the water resource, electricity sector, food production and land occupation in the coal region of the Urussanga River basin (Brazil) were described and compared with the area without the coal industry (Canoas/Pelotas basin, Brazil). Indicators evaluating reliability, robustness, equilibrium and diversity (Shannon index-H) were used to evaluate the impacts of mining on the WELF system. The results indicate that coal provides socioeconomic development in the region; however, it has several negative environmental effects. WELF indicators showed that the Urussanga basin has less robustness in the subsystem of water consumption per capita (0.19), installed electrical capacity (0.01) and agricultural production per capita (0.22) compared to Canoas/Pelotas at 0.73, 1.0 and 1.0, respectively. The basin also presented lower diversity in the water consumption sector (H = 0.81) and in the variety of agricultural products (H = 1.58) compared to Canoas/Pelotas (H = 1.0; H = 1.69, respectively). It was concluded that coal mining can affect the WELF system globally, revealing the need to propose alternatives to prevent and mitigate its effects.

The water&ndash:energy&ndash:land&ndash:food (WELF) nexus is an established framework that allows for a more holistic, systemic and integrated analysis of resources and territorial planning. The main objective of this study was to apply the WELF nexus approach to assess the environmental impacts from coal mining. Data on the water resource, electricity sector, food production and land occupation in the coal region of the Urussanga River basin (Brazil) were described and compared with the area without the coal industry (Canoas/Pelotas basin, Brazil). Indicators evaluating reliability, robustness, equilibrium and diversity (Shannon index-H) were used to evaluate the impacts of mining on the WELF system. The results indicate that coal provides socioeconomic development in the region: however, it has several negative environmental effects. WELF indicators showed that the Urussanga basin has less robustness in the subsystem of water consumption per capita (0.19), installed electrical capacity (0.01) and agricultural production per capita (0.22) compared to Canoas/Pelotas at 0.73, 1.0 and 1.0, respectively. The basin also presented lower diversity in the water consumption sector (H = 0.81) and in the variety of agricultural products (H = 1.58) compared to Canoas/Pelotas (H = 1.0: H = 1.69, respectively). It was concluded that coal mining can affect the WELF system globally, revealing the need to propose alternatives to prevent and mitigate its effects.

This paper introduces and applies iGain4Gains, an Excel-based model, to reveal how changes to water conservation and allocation, and irrigation technology, can produce four nexus gains. These gains are; reduced aggregate water consumption, sustained crop production, lower carbon emissions, and enhanced water availability for nature. We developed the model with limited data and hypothetical future scenarios from the Amman–Zarqa basin in Jordan. Given its significant irrigation and urban water demands and difficult decisions regarding future water allocation and nexus choices, this basin is a highly appropriate case study. The paper’s primary aim is to demonstrate the iGains4Gains nexus model rather than to build an accurate hydrological model of the basin’s water resources. The model addresses two critical questions regarding increased irrigation efficiency. First, can irrigation efficiency and other factors, such as irrigated area, be applied to achieve real water savings while maintaining crop production, ensuring greenhouse gas emission reductions, and ‘freeing’ water for nature? Second, with the insight that water conservation is a distributive/allocative act, we ask who between four paracommoners (the proprietor irrigation system, neighbouring irrigation systems, society, and nature) benefits hydrologically from changes in irrigation efficiency? Recognising nexus gains are not always linear, positive and predictable, the model reveals that achieving all four gains simultaneously is difficult, likely leading to trade-offs such as water consumption rebounds or increased carbon emissions. Demonstrated by its use at a workshop in Jordan in February 2024, iGains4Gains can be used by students, scientists and decision-makers, to explore and understand nexus trade-offs connected to changes in irrigation management. The paper concludes with recommendations for governing water and irrigated agriculture in basins where large volumes of water are withdrawn and depleted by irrigation.

This paper introduces and applies iGain4Gains, an Excel-based model, to reveal how changes to water conservation and allocation, and irrigation technology, can produce four nexus gains. These gains are; reduced aggregate water consumption, sustained crop production, lower carbon emissions, and enhanced water availability for nature. We developed the model with limited data and hypothetical future scenarios from the Amman–Zarqa basin in Jordan. Given its significant irrigation and urban water demands and difficult decisions regarding future water allocation and nexus choices, this basin is a highly appropriate case study. The paper’s primary aim is to demonstrate the iGains4Gains nexus model rather than to build an accurate hydrological model of the basin’s water resources. The model addresses two critical questions regarding increased irrigation efficiency. First, can irrigation efficiency and other factors, such as irrigated area, be applied to achieve real water savings while maintaining crop production, ensuring greenhouse gas emission reductions, and ‘freeing’ water for nature? Second, with the insight that water conservation is a distributive/allocative act, we ask who between four paracommoners (the proprietor irrigation system, neighbouring irrigation systems, society, and nature) benefits hydrologically from changes in irrigation efficiency? Recognising nexus gains are not always linear, positive and predictable, the model reveals that achieving all four gains simultaneously is difficult, likely leading to trade-offs such as water consumption rebounds or increased carbon emissions. Demonstrated by its use at a workshop in Jordan in February 2024, iGains4Gains can be used by students, scientists and decision-makers, to explore and understand nexus trade-offs connected to changes in irrigation management. The paper concludes with recommendations for governing water and irrigated agriculture in basins where large volumes of water are withdrawn and depleted by irrigation.