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The virtual water strategy (VWS) is an effective tool to balance regional water resource endowments and guarantee water supply security. However, because of self‐interested games around VWS (human decision bias), there is a need for methods to maintain reliable cooperation between governments, virtual water (VW) enterprises and research institutions. This study builds a multi‐agent evolutionary game model to analyse the relationship of players and their impacts on VWS through changing decision mechanisms and the paths to enhance their confidence in cooperation. Considering differences in initial willingness to cooperate and changing factors affecting payoffs, an evolutionary game can produce changing stable equilibriums or stable cooperations, even if some players are reluctant to cooperate. Therefore, to promote the development of VWS, a multistep support mechanism can be built for the VW industry, which fosters model enterprises and optimizes the cooperation framework to stimulate research innovations at scientific institutions. Highlights: Traditional virtual water strategy (VWS) studies ignored the specific implementation and stakeholder game issues.A multi‐agent evolutionary game model is built to analyse the stable states and decision mechanisms for VWS.The payoffs of each game player will affect its strategy choice and the speed of model evolution.It is clearly possible for the stakeholders to form a stable equilibrium of long‐term cooperation around the VWS.Changing the factors of one game player may indirectly lead to changes in the strategies of other players. [ABSTRACT FROM AUTHOR]

Commodity exports have played a crucial role in driving global economic growth, but they have also led to increased flow and consumption of natural resources worldwide. To measure and analyse the inter‐regional virtual water consumption and value‐added benefits driven by exports, as well as the unequal exchange between regions, we utilised the global supply chain database of Eora to construct a multi‐regional input–output (MRIO) model of virtual water consumption and value‐added benefits among 189 countries and regions from 1991 to 2016. We also proposed a virtual water consumption uneven index. The results highlight that relatively less developed regions accounted for 27% of the world's total export value added and 56% of virtual water exports. In contrast, relatively developed regions contributed 73% of the global export value added but only 44% of virtual water exports. The export of high‐value‐added products, such as financial services, was concentrated in the relatively developed regions, while water‐intensive products, like agriculture, forestry, and animal husbandry, were mainly exported by relatively less developed regions. Economically developed regions enjoyed a beneficiary position in terms of virtual water consumption, with each unit of export‐driven added value requiring only 4–100 kg of virtual water. Conversely, economically less developed regions consumed 140–1800 kg of virtual water per unit of export‐driven added value. The disparities in virtual water exchanges across different regions primarily stem from the differences between developed and less developed regions. Therefore, less developed regions and countries should focus on improving water efficiency in water‐consuming industries, adjusting the structure of export industries, and striving to reduce or reverse the disadvantageous position of resource consumption, such as virtual water, in global trade exports. [ABSTRACT FROM AUTHOR]

"Invulnerability" of complex network was firstly introduced to virtual water (VW) research, aiming to broaden the scope of studies on water use and management. Beginning with the construction of China's virtual water trade networks (VWTNs) of major grain crops, Node Degree (K) and Betweenness Centrality (B) are employed to evaluate and rank the importance of China's 31 regions. Regions with high values for both indicators are identified as playing pivotal roles in the VWTNs: Jiangsu (ranking 1st for both K and B), Hubei (2nd for K, 3rd for B), Henan (3rd for K, 6th for B), Hebei (4th for K, 4th for B), Hunan (4th for K, 5th for B). Using this ranking to simulate the invulnerability of VWTNs under random and intentional attacks. The results reveal a rapid decrease in both Network Efficiency (E) and Maximum Connectivity (C) under intentional attack. In comparison to seven random attacks, E falls below 0.1 and C drops below 0.5 after only three intentional attacks, and the network completely collapsed after 10 intentional attacks. This highlights the VWTN's vulnerability in maintaining food supply and agricultural water security when key regions are subjected to man‐made destruction, such as military blockades or occupations. Future work should include integrating climate change models, crops yield models, and water resource allocation models to protect the key areas. Furthermore, interdisciplinary approaches are crucial for overcoming the limitations of VW research and these findings will provide valuable insights to enhance the optimal regulation of VWTNs. Key Points: "Invulnerability" was novelly introduced to the virtual water trade networks (VWTNs) to simulate its destruction resistanceNetwork efficiency and maximum connectivity of VWTNs decreased rapidly under intentional attacksWhen key regions subjected to man‐made attacks, China's VWTNs is unable to maintain food supply and agricultural water security [ABSTRACT FROM AUTHOR]

In this study, we examined the impact of climate change on the virtual water content of key crops in Kerman province for future periods. Specifically, we utilized the climatic data from the HadCM3 model under the RCP4.5 radiative forcing scenario. The model was calibrated and validated for the base period of 1991 -2011. We predicted the precipitation levels, as well as the maximum and minimum temperatures, for selected stations from 2011 to 2070 using data from LARS -WG. These predictions were then compared to the base period. The virtual water content was calculated for three selected crops: alfalfa, barley, and wheat. Our findings indicate that climate change has a significant impact on evapotranspiration and the performance of these crops, consequently affecting future agricultural water productivity. As we project an increase in average temperature during the growing season due to climate change, it is worth noting that the maximum temperature parameter will be more affected by this phenomenon than the minimum temperature. This, in turn, will lead to increased water requirements and plant evaporation - transpiration during this period. Our research also reveals a decrease in precipitation during hot seasons and an increase during cold seasons across all study stations. Notably, the virtual water content for all crops studied demonstrates an upward trend, with barley and wheat showing the greatest average increase in the future period. Specifically, the Kerman station exhibits a substantial increase in virtual water content for barley and alfalfa products, at a minimum of 30% higher than the base period. [ABSTRACT FROM AUTHOR]

The main challenges facing the agricultural sector in Sistan plain include scarcity of water resources, inadequate water rationing, and suboptimal cultivation patterns. Based on this, the main objective of this study was to determine the optimal cultivation pattern of agricultural crops by considering the virtual water and water footprint and assessing the impact on water consumption in this region. To achieve this objective, virtual water indicators and green, blue and gray water footprints of agricultural crops were calculated to quantify water consumption in the Sistan region. Then, considering the virtual water and water footprint, the optimal pattern of plant cultivation was determined using a fuzzy ideal programming model. The optimization model results were tested based on a system dynamics approach in the Vensim PLE8.3.5 software. The results showed that the virtual water content of agricultural products in this region was 2.69 m3/kg. The annual water requirement of agricultural crops was 1019 MCM, of which 62% is met. After optimizing the cultivation pattern, the water requirement reduced to 600 MCM per year, of which 89% is supplied. Additionally, the optimization of cultivation patterns increased water supply to the environmental sector from 138 to 240 MCM per year.

Agricultural water productivity is crucial for sustainability amidst the escalating demand for food. Cereals are pivotal in providing nutritious food at affordable prices. This study was based on Ghanaian data spanning from 1992 to 2021 to evaluate water usage in the cultivation of major cereals. It also examined the virtual water losses or gains in cereal trade alongside influencing factors. The analysis utilized secondary data encompassing the virtual water content, production quantity, export and import quantities, distance, GDP per capita, population, and land per capita of Ghana and its 75 trade partners. In the last 5 years, crop water use (CWU) reached an average of 7.08 billion m3/yr for maize, 3.48 billion m3/yr for rice, 1.08 billion m3/yr for sorghum, and 0.63 billion m3/yr for millet production. Ghana's major partners for exported virtual water (EVW) were Niger, Burkina Faso, South Africa, and Togo. Major partners for imported virtual water (IVW) were Argentina, South Africa, Ukraine, Togo, Russia, Burkina Faso, Canada, Senegal, Nigeria, Portugal, UK, Niger, and the USA. The Panel Least Squares Method of regression was used to apply the Gravity Model principle in assessing influencing factors. The findings indicate that Ghana is a net importer of virtual water in the cereal trade, with significant influences from geographical distance, GDP per capita, population, land per capita, and cereal water use. [ABSTRACT FROM AUTHOR]

Incorporating water footprints and virtual water into crop redistribution provides a new approach for efficient water resources utilization and synergistic development of water surplus and scarce regions. In this work, the absolute and comparative advantage of the production‐based blue and gray water footprint (PWFblue and PWFgray), the calorie‐based blue water footprint (CWFblue) and the net benefit‐based blue water footprint (NBWFblue) were used as coefficients to establish a bi‐level crop redistribution model. The mode considers upper‐level decision makers interested in maximizing food security and ecological security and lower‐level decision makers interested in water use efficiency, water use benefits and net benefits. The model was applied in the Hetao Irrigation District (HID), China. The results showed that after optimization, the PWFblue, CWFblue, NBWFblue, and gray water footprint (GWF) of the HID were reduced by 23.32%, 5.60%, 17.40%, and 6.67%, respectively. National benefits were improved, especially when considering synergistic optimization, although the net benefits of HID was affected. The calorie supply increased by 9.6 × 109 kcal, the GWF decreased by 8.29 × 106 m3, and water use efficiency and benefits were improved in China. In contrast, the calorie supply and the net benefits of the HID decreased, while the GWF increased. Moreover, multiple stakeholders were involved in crop redistribution and required national synergies. The bi‐level model proved more suitable than the multi‐objective model. The model proposed in this work considers synergies outside the region in crop redistribution within the region, and can provide new insight for water and soil resources management in arid and semi‐arid regions. Key Points: Virtual water flow embedded in optimization model reflecting comparative advantageAbsolute advantage and comparative advantage synergize interregional interestsBi‐level optimization model trade‐offs regional authority and sub‐regions [ABSTRACT FROM AUTHOR]

This article is an attempt to understand a mesh of complex relationships among tangible and intangible socio-economic factors that turned a desert city into the headquarters of one of the mighty polities in the Middle East in the fourteenth century CE. This paper argues that proto-industrialization led to the growth of 'virtual water' that helped the city of Yazd, in central Iran, to break free from its water limitation for the first time in its history. Yazd was almost absent in history until the twelfth century, as a peripheral oasis whose sparse population lived off subsistence agriculture irrigated by qanat systems (groundwater-mining subterranean channels). Following the Mongol invasion in the thirteenth century, the influx of landless refugees changed the relations of production and paved the way for proto-industrialization whose development hinged on skill and capital rather than water and land. Sufism and waqf (endowment tradition) contributed to the expansion of trading routes that facilitated the mobility of goods and people. The qanats were urbanized, and Yazd became an industrial hub where raw materials were processed into tradable products with considerable value added. This paper contributes to a broader understanding of the historical geography of the arid Middle East. • The Iranian city of Yazd rode out the Mongol invasion in the thirteenth century. • A surge of refugees upset the balance between population and agricultural resources. • Abundance of skilled workers led to a Middle Eastern mode of proto-industrialization. • Proto-industrialization engendered virtual water as an adaptation strategy. • Virtual water made a transition to a non-hydraulic society. [ABSTRACT FROM AUTHOR]

Civil infrastructure underpins urban receipts of food, energy, and water (FEW) produced in distant watersheds. In this study, we map flows of FEW goods from watersheds of the contiguous United States to major population centers and highlight the critical infrastructure that supports FEW flows. To do this, we draw upon detailed records of agriculture, electricity, and public water supply production and couple them with commodity flow and infrastructure information. We also compare the flows of virtual water embedded in food and energy commodity flows with physical water flows in inter‐basin water transfer projects around the country. We found that the virtual blue water transfers through crops and electricity to major US cities was 53 billion and 8 billion m3 in 2017, respectively, while physical interbasin water transfers for crops, electricity, and public supply water averaged 20.8 billion m3. Highways are the primary infrastructure used to import virtual water associated with food and fuel into cities, although waterways and railways are most utilized for long‐distance transport. All of the 204 watersheds in the contiguous US support the food, energy, and/or water supplies of major US cities, with dependencies stretching far beyond each city's borders. Still, most cities source the majority of their FEW and embedded water resources from nearby watersheds. Infrastructure such as water supply dams and inland ports serve as important buffers for both local and supply‐chain sourced water stress. These findings can inform efforts to reduce water resources and infrastructure risks in domestic supply chains. Key Points: Civil infrastructure enables US cities to access FEW resources from distant watershedsMost cities depend on nearby watersheds for FEW and embedded waterVirtual water transfers through food and energy exceed physical water transfers [ABSTRACT FROM AUTHOR]

Study region: The Yellow River Basin (a water-deficient region) in China. Study focus: The redistribution of virtual water through trade holds potential to enhance water security in the Yellow River Basin. We explored a virtual water tri-circulation model at the city level to mitigate water stress in the Yellow River Basin. The tri-circulation model includes internal, external and international virtual water flows. This research investigated the heterogeneity of virtual water trade between upstream and downstream regions, identified key regions and sectors to facilitate physical water redistribution and enhance regional cooperation. New hydrological insights for the region: This study revealed that the Yellow River Basin received virtual water amounting to 8.40 % of its total virtual water consumption, with external circulation being the key circulation. Upstream regions primarily exported water resources to downstream regions and developed regions outside through agricultural trade, while downstream regions received water from upstream regions and underdeveloped regions outside through trade in agri-food products and other service industries. International circulation exported virtual water through water-intensive agricultural products, contributing to increased local environmental burden. Increased attention should be paid to virtual water transfers of the external circulation, implementing compensation strategies, and fostering technical interaction between upstream and downstream regions, and safeguarding upstream agricultural and ecological water to promote the sustainable development of the Yellow River Basin.

The interprovincial circulation of goods and services has formed virtual water flows between regions, which can redistribute water resources. Based on previous virtual water trade research, this study further explored the multiple dependencies of virtual water, i.e., direct, indirect, and complete dependence. This study examined the direct, indirect, and complete dependence of virtual water between provinces in China by constructing multilayer dependence networks and identified the key regions and paths of virtual water trade network. The results showed direct dependence was the densest and had the largest overall dependence degree, but indirect dependence was the most stable and orderly. Second, the dominant provinces were Guangxi, Hunan, Sichuan, Xinjiang, and Anhui, referred to as "core‒five‒region," and the flow relevant to them accounted for approximately 30% of the virtual water. The seven provinces of Shanxi, Zhejiang, Shandong, Hubei, Guangdong, Shaanxi, and Gansu depend both directly and indirectly on the "core‒five‒region." Shanxi and Zhejiang have close direct and indirect dependence, with more than one of the "core‒five‒region." Guangdong was the province with the most direct and indirect input of virtual water from the "core‒five‒region." The study provides a scientific basis for multiregional identification for the collaborative management of water resources in China from the perspective of dependence. [ABSTRACT FROM AUTHOR]

Given the need for water use to be a crucial consideration in sustainable development, an adequate water allocation system across economic sectors is essential, especially in the face of increasing seasonal and perennial water scarcity. In an attempt to facilitate a socially and economically efficient adaptation to the climate emergency, we propose a set of eleven socio-economic indicators to analyze the current water management. This set of indicators could help to quantify the interrelationship between water use and its economic perspective, as well as its social perspective through its impact on employment. Any demand for water not only includes the direct use of water but also its indirect use, referred to as virtual water. This is the water indirectly used through the other inputs in the production process (input–output methodology). These indicators are evaluated in the South-West Europe territory where, in light of increasing water scarcity, there is a need to orientate water allocation toward employment with less intensive water use, to more water productivity and to less environmental impacts. The results at river basin scales show that water use is more productive in the tertiary than in the secondary and primary sectors. [ABSTRACT FROM AUTHOR]

In response to the growing disparity between the supply and demand of water resources, the Chinese government has piloted a more binding and reformed water resources tax to realize the sustainable utilization of water resources. However, reasonable tax standards and their water-saving effects and economic benefits are important and worthy of attention. Therefore, in this study, we combine the virtual water theory with the price input–output model to discuss the impact of water resources taxation on the economy and its water-saving effects. The results show the following: (1) A water resources tax has a significant water-saving effect, and is predicted to save 33.12 billion cubic meters of virtual water. (2) Consumers' expected reductions in spending on food and tobacco manufacturing and agriculture are predicted to save more virtual water at a lower economic cost. (3) The collection of water resources taxes can actively and simultaneously guide water savings in terms of consumption and production. The water consumption of the construction industry is worthy of attention. The expected output value reduction accounts for 67.2% of the total output value reduction, and its water savings account for 96% of the total water savings. Other service sectors also have ample room to optimize the utilization of their water resources. [ABSTRACT FROM AUTHOR]

Abstract Civil infrastructure underpins urban receipts of food, energy, and water (FEW) produced in distant watersheds. In this study, we map flows of FEW goods from watersheds of the contiguous United States to major population centers and highlight the critical infrastructure that supports FEW flows. To do this, we draw upon detailed records of agriculture, electricity, and public water supply production and couple them with commodity flow and infrastructure information. We also compare the flows of virtual water embedded in food and energy commodity flows with physical water flows in inter‐basin water transfer projects around the country. We found that the virtual blue water transfers through crops and electricity to major US cities was 53 billion and 8 billion m3 in 2017, respectively, while physical interbasin water transfers for crops, electricity, and public supply water averaged 20.8 billion m3. Highways are the primary infrastructure used to import virtual water associated with food and fuel into cities, although waterways and railways are most utilized for long‐distance transport. All of the 204 watersheds in the contiguous US support the food, energy, and/or water supplies of major US cities, with dependencies stretching far beyond each city's borders. Still, most cities source the majority of their FEW and embedded water resources from nearby watersheds. Infrastructure such as water supply dams and inland ports serve as important buffers for both local and supply‐chain sourced water stress. These findings can inform efforts to reduce water resources and infrastructure risks in domestic supply chains.

The regional comprehensive economic partnership (RCEP) is today the largest free trade area in the world. This paper examines agricultural trade in the RCEP from 2010 to 2019 through the perspective of virtual water. And the drivers of the virtual water flow between China and the RCEP are also explored. The results are as follows: the virtual water flow during the study period was 2,576.51 billion m3. From a temporal perspective, the annual virtual water flow over the study period is characterized by a slow rise–significant fall–slow rise. It has the characteristics of concentration in spatial distribution and water resources and product structure. However, the concentration degree showed a downward trend during the study period. Then, we have divided the major trading into four categories based on whether there is a shortage of water on both sides of the trade. In terms of the drivers of virtual water flows between China and the RCEP, we have used the gravity model to arrive at the following findings: crop yields, bilateral economic scale, and agricultural labor resources are the main drivers. Our research results have reference values for adjusting bilateral agricultural trade and water conservation. HIGHLIGHTS The virtual water flow has the characteristics of spatial concentration.; The virtual water trade relations are divided into four categories.; The structure of the virtual water flows is relatively concentrated.; The driving factors are analyzed by using the gravity model.;

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Agricultural production is considered the main cause of water use and water pressure. Gray water footprint has provided new research perspectives for studying water pollution of agricultural production. Scholars have gained abundant research achievements in agricultural gray water footprint, which is still updating and developing, and lacks systematic accounting methods, spatial distribution patterns, and influencing factors. Firstly, the development process of the agricultural gray water footprint accounting model was reviewed. Then, the current research of the spatial patterns of gray water footprint was analyzed from perspectives of crop types, gray water footprint accounting scales, and accounting allowable limits. Finally, the impacts of factors such as the application of pesticides and fertilizers, the depth of economic and capital development, urban-rural structure, technological and industrial structure, population, and social welfare on the total change of agricultural gray water footprint were summarized, and the shortcomings in the assessment of gray water footprints and the breakthrough points for future research were presented. The comprehensive results can provide new research perspectives for subsequent scientific accounting of agricultural gray water footprint and, at the same time, offer theoretical support for regional agricultural sustainable development. [ABSTRACT FROM AUTHOR]

This study utilizes a system dynamics approach (SD) to assess the effects of water productivity improvement strategies on the Qazvin plain, Iran, and the uncertainty of the individual and interactive effects. The key indicators included in the important strategies are cropping pattern scenarios (CPS), deficit irrigation (DI), and modern irrigation systems development (MISD). Plain-scale results show that CPS 7, CPS 4, and CPS 8 had the highest physical water productivity (WPp) at 2.11, 1.99, and 1.95 kg/m3, respectively, representing a 21, 14, and 12 percent increase over CPS 1. Compared with CPS 1, CPS 4, CPS 6, and CPS 8 showed the highest values of WPe (5678, 5568, and 5503 Rials/m3, respectively). At the field scale, under DI, WPp increased for all crops (except corn, which was the most sensitive), but WPe is only increased for tomato, canola, pea, and barley and reduced for corn, potato, beans, lentils, and sugar beet. The WPe was affected by the DI, the irrigation system type, and the CPS. CPS 7 and CPS 6 had the highest and lowest water requirements, respectively, with 11,699 and 8207 m3/ha. Volume decline in aquifers is significantly affected by both CPS and DI. The CPS6, CPS8, and CPS2 were better than other scenarios. By modifying the cropping pattern, it is possible to prevent aquifer decline, thus improving the aquifer status (CPS5). MISD increased both field and plain WPp for all crops. The MISD improved groundwater resources and reduced demand by increasing efficiency to improve aquifer condition. [ABSTRACT FROM AUTHOR]

Abstract This study utilizes a system dynamics approach (SD) to assess the effects of water productivity improvement strategies on the Qazvin plain, Iran, and the uncertainty of the individual and interactive effects. The key indicators included in the important strategies are cropping pattern scenarios (CPS), deficit irrigation (DI), and modern irrigation systems development (MISD). Plain-scale results show that CPS 7, CPS 4, and CPS 8 had the highest physical water productivity (WPp) at 2.11, 1.99, and 1.95 kg/m3, respectively, representing a 21, 14, and 12 percent increase over CPS 1. Compared with CPS 1, CPS 4, CPS 6, and CPS 8 showed the highest values of WPe (5678, 5568, and 5503 Rials/m3, respectively). At the field scale, under DI, WPp increased for all crops (except corn, which was the most sensitive), but WPe is only increased for tomato, canola, pea, and barley and reduced for corn, potato, beans, lentils, and sugar beet. The WPe was affected by the DI, the irrigation system type, and the CPS. CPS 7 and CPS 6 had the highest and lowest water requirements, respectively, with 11,699 and 8207 m3/ha. Volume decline in aquifers is significantly affected by both CPS and DI. The CPS6, CPS8, and CPS2 were better than other scenarios. By modifying the cropping pattern, it is possible to prevent aquifer decline, thus improving the aquifer status (CPS5). MISD increased both field and plain WPp for all crops. The MISD improved groundwater resources and reduced demand by increasing efficiency to improve aquifer condition.

【Objective】 This paper aims to assess the indirect influence of virtual water flow on metropolitan-scale agricultural water stress in Sichuan province. It investigates the spatiotemporal variation in this context, elucidating how persistent growth in agricultural water use and the movement of virtual water through agricultural products across the province indirectly impacts regional water stress. 【Method】 The AquaCrop model was employed to calculate the water footprint of 16 different crops from 2000 to 2018 in all metropolitan cities within the province. The calculation of inter-province virtual water flow was based on annual balance between crop production and food demand, by considering the minimum transportation costs cross the province. These calculated results were then used to analyze the influence of virtual water flow on agricultural water stress. 【Result】 From 2000 to 2018, the average water footprint of crop production in Sichuan was estimated to be 28.4 billion cubic meters per year. The total water footprint of crop production in the province exhibited a fluctuation during the studied period, with the most notable change observed in Leshan. The province experienced a net increase in virtual water inflow, with the Western areas receiving more inflow than the Eastern regions. The continuous influx of virtual water has contributed to the alleviation of agricultural water stress in the province, reducing the number of cities experiencing increased water stress due to virtual water outflows from four in 2000 to one in 2018. 【Conclusion】 The analysis of physical and virtual water highlights the need for Sichuan province to enhance the regulation and optimization of virtual water trade as a means to mitigate agricultural water stress.

This article aims to find out the impact of water in the process of sustainable agricultural development in Iraq, by presenting the reality of water resources in Iraq and water sources with reference to water sources globally and at the level of the Arab world, the low efficiency of the use of water resources in Iraq, which was considered one of the biggest challenges that led to the depletion of this important and vital resource, as it did not exceed in the best cases 40%, which is a small percentage if compared to neighboring countries and the Arab homeland. Moreover, the study did not indicate any trend to use virtual water as a more rational alternative to importing water between the high costs of water and its transportation, and it was also shown through the study that there are many challenges that affected water management in Iraq, including water share and water security, as well as shared water with neighboring and upstream countries. The study recommended supporting and encouraging the use of modern irrigation systems (sprinklers) to raise the efficiency of water use and link water security with food security because of their major role in raising the process of sustainable agricultural development in Iraq As well Aa activating the rule aquatic Agricultural extension because of its role in guiding and guiding farmers in rationalizing the use of water resources and urging them to adopt modern irrigation technologies.

Agricultural water productivity is crucial for sustainability amidst the escalating demand for food. Cereals are pivotal in providing nutritious food at affordable prices. This study was based on Ghanaian data spanning from 1992 to 2021 to evaluate water usage in the cultivation of major cereals. It also examined the virtual water losses or gains in cereal trade alongside influencing factors. The analysis utilized secondary data encompassing the virtual water content, production quantity, export and import quantities, distance, GDP per capita, population, and land per capita of Ghana and its 75 trade partners. In the last 5 years, crop water use (CWU) reached an average of 7.08 billion m3/yr for maize, 3.48 billion m3/yr for rice, 1.08 billion m3/yr for sorghum, and 0.63 billion m3/yr for millet production. Ghana’s major partners for exported virtual water (EVW) were Niger, Burkina Faso, South Africa, and Togo. Major partners for imported virtual water (IVW) were Argentina, South Africa, Ukraine, Togo, Russia, Burkina Faso, Canada, Senegal, Nigeria, Portugal, UK, Niger, and the USA. The Panel Least Squares Method of regression was used to apply the Gravity Model principle in assessing influencing factors. The findings indicate that Ghana is a net importer of virtual water in the cereal trade, with significant influences from geographical distance, GDP per capita, population, land per capita, and cereal water use.

The management of water resources requires a correct understanding of the simultaneous management of food and energy resources. The framework of water–food–energy correlation with the approach of sustainability of resources and uses analyzes the combined management and exploitation of water, food, and energy resources with the help of scenario planning. In addition to sustainability concepts, environmental costs such as the emission of carbon dioxide from fossil fuels and its impact on the environment are also discussed. In this research, according to the five defined indicators and based on the potential of using solar energy and the possibility of exploiting renewable energy sources such as solar energy, various management scenarios have been developed. After examining the virtual water management model developed in the Hunan basin as a case study, the development of the water–food–energy nexus model and its calibration, and four scenarios including improving water use efficiency, energy saving, increasing food productivity, and nexus sustainability were developed. The results showed that the nexus strategy can provide sustainability goals according to the weight of each component. After the combined scenario, improving the efficiency of water consumption can be the component with the highest priority in the decision-making model in dry areas. HIGHLIGHTS The water–food–energy nexus is evaluated as a conceptual approach for achieving sustainable management.; Improving water use efficiency, energy saving, increasing food productivity, and nexus sustainability were considered.; The developed approach provides a significant contribution to achieving regional sustainable development goals.;

The escalating challenges regarding the sustainable utilization of coupled energy and water resources require the implementation of synergistic management. Electricity-related virtual water flows could result in the transfer of freshwater vulnerability and environmental inequalities. Aiming to systematically characterize its holistic patterns, network structure and formation mechanisms, we constructed a virtual water network for electricity trade in China based on provincial lifecycle water footprints; portrayed the statistical features, structural stability and interregional equilibrium using Complex Network Analysis (CNA); and introduced the Quadratic Assignment Procedure (QAP) to gain socio-environmental insights into the driving factors. The results show that the virtual water transferred with China's interprovincial electricity trade increased from 851.24 million m3 to 3441.58 million m3 from 2006–2020. Eastern, developed provinces with a high electricity demand have effectively relieved their water stress by expanding import sources, but the transfer of water resource benefits from western exporting regions (especially in the arid northern provinces) is irreversible. The current electricity market forces reflect the scarcity of energy and capital factors in the context of China's interprovincial trade, but not the scarcity of water resources. Consequently, we proposed integrated management strategies including strengthening sectoral collaboration, optimizing energy-use structures and establishing ecological compensation mechanisms to build a more water-efficient future power system. [ABSTRACT FROM AUTHOR]

Traditional methods of irrigation and resource utilization lack an organized strategy for managing water resources. There are often inefficiencies in the way irrigation water is used in fields and plains, leading to irrigation waste and inefficient water utilization. Considering the size and dispersion of the land, the variety of crops, the time and location at which they are planted, and the distance between the source of water and the point where it is consumed, irrigation and drainage networks are essential for the best management of water resources. Therefore, in the present study, we have attempted to optimize the use of water in the agricultural sector by taking into account both the virtual water of plant cultivation and growth as well as the environmental conditions relevant to it, both geographically and temporally. Based on the calculations presented in this research and comparisons with the existing traditional method, the amount of water consumed in agriculture in the study area, which is part of Isfahan Province's southern part in the Gavkhoni lagoon, is estimated to be approximately 70 percent reduced if the solution presented in this study is implemented. It would be equivalent to using about 30% of the amount of water currently consumed and something equivalent to about 300 thousand cubic meters of water consumption reduction, which is a significant amount. [ABSTRACT FROM AUTHOR]

Understanding the water requirement of electricity generation is critical to the development of both electricity and water systems, while the water consumption of the whole electric power system remains unrevealed. Here, we examine the water consumption driven by electricity generation, transmission, and consumption in China, finding that 14 billion m3 of freshwater is consumed by electricity generation in 2019 and that 2.5 billion m3 of freshwater was virtually transferred via electricity transmission. Nationally, the freshwater consumption per unit of electricity generation was 1.9 m3/MWh. Based on the state-of-the-art electricity transmission data, we find that 59% of the transported electric power was from water-scarce provinces and 0.7 billion m3 of freshwater was lost due to the electricity loss in transmission lines in China. It is essential to link water resources with the whole electric power system (production, transmission, and consumption) rather than only part of the power system as in previous research. [ABSTRACT FROM AUTHOR]

The virtual water trade in a region is affected by both natural factors and human activities. In order to quantitatively study the influence of human activities to the virtual water trade, a new quantitative comparative analysis method was proposed in this paper. By adjusting the natural climate factors into a uniform standard, this paper quantitatively analyzed the impact of the increase and decrease of external water diversion and the strictest water resources management policies on the virtual water trade in agricultural and industrial sectors by year and inter-year. Taking Shandong Province as an example, this study applied this method to make a quantitative analysis of virtual water trade in Shandong Province in the past 20 years. The results show that with the development of economy, the net output curves of agricultural and industrial virtual water are U-shaped and irregular inverted U-shaped, respectively. Virtual net water output can adversely affect the local water environment. In 1997, when the Yellow River stopped flowing, the decrease of water diversion reduced the net virtual water output of agriculture and industry by 20.13% and 49.67%, respectively. In 2017, the input of the South-to-North Water Diversion Project increased the net virtual water output of agriculture and industry by 1.32% and 41.99%, respectively, compared with that without the diversion, while the implementation of the strictest water resources management policy reduced it by 10.01% and 20.39%, respectively. [ABSTRACT FROM AUTHOR]

Virtual water exerts an indispensable influence on water resources, yet the existing studies on the water rights allocation of transboundary rivers hardly consider virtual water transfer (VWT). Therefore, in this paper, we used Taihu Lake as an example with data collected in 2017 that described both physical and virtual water use. We used these data to evaluate water rights allocation schemes by coupling virtual and physical water use. In order to achieve this goal, we first determined the physical water rights allocated for the four regions connected to the Basin. Next, we employed the multi-regional input–output (MRIO) approach to calculate the VWT among the four regions; then, we converted the VWT to the riparian level via the water efficiency coefficient. Finally, with virtual water included in the physical water rights allocation, we formulated a final water rights allocation for Taihu Lake. The results showed the following findings: (1) The ranking of the amount of physical water rights allocation is: Jiangsu > Zhejiang > Shanghai > Anhui. (2) Anhui and Jiangsu produce a net export of virtual water (2.259 billion m3 and 1.78 billion m3, respectively), while Zhejiang and Shanghai have a net import of virtual water (2.344 billion m3 and 1.695 billion m3, respectively), indicating that Anhui houses more water-consuming industries and is in greater need of economic restructuring. (3) The integration of virtual water makes a difference: Jiangsu achieved 16.208 billion m3 in terms of the amount of water rights allocated, Zhejiang achieved 6.606 billion m3, Shanghai achieved 3.040 billion m3, and Anhui achieved 4.319 billion m3, with a ranking of Jiangsu > Zhejiang > Anhui > Shanghai. The results detailed above prove that virtual water exerts an indispensable influence, and integrating virtual water can make the physical water rights allocation of transboundary rivers more equal and reasonable. [ABSTRACT FROM AUTHOR]

China is facing serious water scarcity, and the effects of international trade on its water resources have been widely examined. Processing exports account for nearly half of China's gross exports. Adopting China's multi-regional input–output table that captures processing exports, we enrich the literature on virtual water exports by accounting for trade heterogeneity. The results show that China's virtual water exports show a significant trade heterogeneity. Normal and processing exports are attributed to 86.7% and 13.3% of the Agriculture sector's water use induced by exports respectively. Conversely, normal and processing exports are attributed to 31.8% and 68.3% of the Communications Equipment, Computers sector's water use induced by exports respectively. In addition, a cross-regional compensation is needed to deal with the unequal regional distribution of water uses and economic benefits related to exports. [ABSTRACT FROM AUTHOR]

IntroductionThe increase in demand for water resources due to population growth and economic development along with water wastage and a decrease in rainfall, on the other hand, has made it significant to pay attention to water demand and make sound policies. Our country is facing the risk of a water crisis in the coming years, mainly due to its location in a dry and semi-arid climate, as well as the ever-increasing growth of water consumption. To alleviate the water crisis, international trade in agricultural products can play a significant role in redistributing water resources because traded goods contain a large amount of virtual water. Water restriction in Iran is an undeniable fact, for this purpose, trading based on virtual water can be a solution to reduce the effects of water restriction. Due to being located in a dry and semi-arid climate, Iran is facing the risk of a water crisis in the coming years. Therefore, in order to deal with it, it is necessary to be more sensitive to the types of water consumption. Among these uses is virtual water. The water used in the production process of goods is called virtual water, a part of which is kept in the product. Virtual water trade occurs when goods are imported into global markets. Virtual water trading is expected to reduce water consumption at the national and international levels due to more efficient and specialized use of water. Today, the concept of virtual water is one of the most critical issues in water resources management. Today, the problem of water shortage has become a serious concern due to climate changes and uneven distribution of rainfall in most regions and countries, including Iran, and is considered the most important obstacle to the economic development of these countries. Trade as a tool to prevent the unnecessary withdrawal of water resources, focusing on the strategy of virtual water trade, can play an essential role in achieving the economic development of countries. Materials and Methods The study area of the research is the Shiblo-Poldasht plain in the northwest of Iran. This area is located in the east of the Poldasht study area and in the north of the Qara Ziauddin study area. The aim of this research was to investigate the statistical status of the cultivated area, the production performance, and the evaluation of the productivity and virtual water of agricultural crops in the Poldasht plain. The time frame of the research is from 2011 to 2021 in an 11-years period. Accurate calculation and determination of water requirement (m3 ha-1). The amount of water required by a plant for its proper growth, taking into account the loss of evaporation and transpiration of the plant, is called the water requirement of the plant. Therefore, the water requirement of the plant depends on the amount of evaporation and transpiration of the plant. It is worth noting that due to different climates and weather conditions, plant growth conditions and as a result, the amount of water needed by plants are also different. In the present research, the various productivity indicators and virtual water of the crops of Dasht-Poldasht have been examined. Moreover, according to the objectives of the research, the physical and financial indicators of water productivity, including the performance index per unit of water volume (CDP), income per unit of water volume (BPD), and net return per unit of water volume (NBPD) have been calculated. Results and Discussion In this research, the amount of virtual water and the productivity index as well as the net and gross economic value of the major crops grown in Poldasht city in West Azarbaijan province were investigated. In this regard, first, data and information related to crops were collected through relevant organizations and institutions, and NETWAT, CROPWAT, and CLIMWAT programs and Excel programs were used to draw graphs and graphical results. Then the yield of crops was calculated by dividing the amount of crops produced by the area of ​​planting crops and the productivity index and virtual water. The results of this research show that the watermelon crop with a harvesting area of ​​5789 ha and a production rate of 237951000 kg and a production yield of 41103.99 kg ha-1 with a water requirement of 2760 m3 ha-1 has a productivity of 14.89 kg m-3 and has The highest level of productivity is also the results show that the alfalfa product is the lowest level of productivity. It is worth noting that despite the fact that the watermelon product has high production and productivity at a very low harvest level, it is also a very water-loving product that has a relatively high water requirement, and generally experts are looking for an alternative product due to the lack of water resources. Finally, it is suggested that traditional (submerged) irrigation methods should be replaced by modern pressurized irrigation methods so that in addition to increasing efficiency and productivity, we can see a reduction in water consumption and its wastage. It is also suggested that the water requirements of agricultural crops be compared with each other using the data of the Agricultural Jihad Organization and the aforementioned programs, and its effect on the amount of water consumed and its savings, as well as the net and gross values ​​of the production of crops, and the final results It is compared with the national water document to fully verify the amount of water needed. Conclusion Despite the fact that the watermelon product has high production and productivity at a very low harvest level, it is also a very water consuming product possessing a relatively high water requirement, and generally experts are looking for an alternative product, due to the lack of water resources. Finally, it is suggested that traditional flood irrigation methods should be replaced by modern pressurized irrigation methods, so that in addition to increasing efficiency and productivity, we can encounter with a reduction in water consumption and its wastage. It is also suggested that the water requirement of agricultural crops should be compared with each other using the data of the Agricultural Jihad Organization and the aforementioned programs, and its effect on the amount of water consumed and its saving, as well as the net and gross values of crop production, should be evaluated. Finally, the results have been compared with the national water document so that the amount of water needed can be fully verified.

Given the need for water use to be a crucial consideration in sustainable development, an adequate water allocation system across economic sectors is essential, especially in the face of increasing seasonal and perennial water scarcity. In an attempt to facilitate a socially and economically efficient adaptation to the climate emergency, we propose a set of eleven socio-economic indicators to analyze the current water management. This set of indicators could help to quantify the interrelationship between water use and its economic perspective, as well as its social perspective through its impact on employment. Any demand for water not only includes the direct use of water but also its indirect use, referred to as virtual water. This is the water indirectly used through the other inputs in the production process (input–output methodology). These indicators are evaluated in the South-West Europe territory where, in light of increasing water scarcity, there is a need to orientate water allocation toward employment with less intensive water use, to more water productivity and to less environmental impacts. The results at river basin scales show that water use is more productive in the tertiary than in the secondary and primary sectors.

Agricultural trade, which involves the exchange of virtual water and land resources, can effectively regulate the allocation of resources among countries while enhancing the well-being of resource-rich and resource-poor nations. China's animal products trade market concentration is greater, and the livestock industry consumes more water than other agricultural sectors. In order to alleviate the pressure on China's domestic water and land resources and to ensure that Chinese residents have access to animal products, this article examines the trade situation and drivers of virtual water and land resources related to Chinese animal products trade. This study used the heat equivalent method to measure the virtual water and land flows of the import and export of beef, pork, and mutton from 1992 to 2018, which is followed by the gravity model to investigate the factors impacting China's flow of virtual land and water related to livestock products trade. We found that the economic development and the agricultural resources of exporters, as well as China's agricultural employment rates, have a stable beneficial impact on China's livestock imports. The population of importing nations, China's cultivated land area, and the livestock production index of importers and exporters have a positive impact on the export of livestock products from China. Our results remain robust following a series of additional tests. [ABSTRACT FROM AUTHOR]

Copyright of Water Conservancy Science & Techonlogy & Economy is the property of Water Conservancy Science & Technology & Economy Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Virtual water exerts an essential effect on water resources, yet such effect is rarely considered in current studies on water rights allocation in transboundary rivers. Hence, this paper ran a case study on Taihu Lake Basin, collecting data from 2017 to make clear the physical water rights of four regions—Jiangsu Province, Zhejiang Province, Anhui Province, and Shanghai City—in the Basin. After that, the multiregional input–output (MRIO) approach was utilized to measure the trade in value-added (TiVA) transfer and virtual water transfer (VWT) and construct an inequality index of VWT (VWI). Next, water efficiency coefficient was employed to convert the VWT into riparian level. Finally, VWT and VWI were incorporated into the water rights allocation model to form up a water rights allocation scheme for Taihu Lake Basin. Results showed: (1) Jiangsu enjoys the most allocated physical water rights, followed by Zhejiang, and Anhui ranks the lowest; (2) Anhui and Jiangsu are net virtual water exporters (2.259 billion m3 and 1.78 billion m3, respectively), while Zhejiang and Shanghai are net importers (2.344 billion m3 and 1.695 billion m3, respectively); (3) Anhui suffers the most inequality—0.4401—followed by 0.5076 of Jiangsu, while Zhejiang has the most equal environment—0.7012; (4) after the inclusion of virtual water, the quantity of water rights allocation changes, whereas Anhui experiences the largest growth—144 million m3—due to the dual effects from the highest VWT and inequality. In conclusion, the effect of virtual water is indispensable, so VWT and VWI should both be considered in the physical water rights allocation of transboundary rivers. [ABSTRACT FROM AUTHOR]

It is necessary to use the correct methods of water economic valuation. Proper use of the virtual water concept and the crop pattern can play a significant role in increasing water productivity and sustainable development. In this paper, the economic value of agricultural water, once without considering virtual water and once again with virtual water for four crops including wheat, barley, alfalfa and fodder maize was calculated, using a native-exclusive mathematical model, in Isfahan province, counties of Shahinshahr-Meymeh and Borkhar, Iran. Three weighting methods based on cultivated area, volume of net water consumption and product income were considered for water valuation. The input data for the mathematical model includes crop parameters, meteorological data, the amount of water consumed for each plant and the amount of expenses and incomes from each product for the crop year 2020-2021. The obtained results showed that by all the three weighting methods and in the both studied areas, the economic value of agricultural water increased by considering the virtual water of crops and changing the crop pattern accordingly; the water economic value by three weighting methods based on cultivated area, the amount of water consumed, and crop income increased by 22%, 44%, and 23% in Shahinshahr-Meymeh county and by 17%, 15%, and 15% in Borkhar county, respectively. This research showed that considering virtual water and changing the crop pattern accordingly can increase the economic value of water, reduce water consumption and help achieve sustainable development. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Kirkuk University for Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Because of severe water scarcity, it is crucial to quantify water use in China's water-scarce regions and to analyze the factors driving its use. In this paper, we analyze the driving factors behind the water footprint from 2007 to 2017 in the mildly water-scarce region of Anhui Province, using regional input–output models and structural decomposition analysis. The results show the following: (1) Although the average virtual water intensity of Anhui Province decreased by 52.58% from 2007 to 2017, the water-use efficiency was still low; (2) During the study period, the total water footprint of Anhui Province increased by 25.06%, with an obvious upward trend; (3) From 2012 to 2017, the net export volume of virtual water in Anhui Province was positive, and the flow volume decreased by 78.87%; (4) Technological progress contributed the most to reducing the water footprint of Anhui Province, followed by the increased counter-urbanization rate as the second-largest driving force. The expansion of the scale effect, including the size of the economy and the size of the population, was the main negative driving force for the increase in Anhui's water footprint. However, the proportion of economic scale in the water footprint drivers gradually decreased. [ABSTRACT FROM AUTHOR]

As a water-scarce country and the world's largest trader of industrial products, China's industrial virtual water (VW) flow may exacerbate its water scarcity problem. Thus, industrial VW flows' spatial and temporal evolution in international trade should be analyzed, and influencing factors must be identified. This study developed the multiregional input–output (MRIO) model, combined with the Leontief inverse matrix, to measure and decompose the industrial VW flows between China and other economies from 2000 to 2014. This extended MRIO model considers intermediate production water consumption and indirect water use, which technically distinguishes the sources of pressure on water use more accurately, thus enabling a new elaboration of the composition of China's industrial water use. Then, the evolution of China's industrial VW trade is analyzed spatiotemporally, and the structural decomposition analysis (SDA) method is invoked to identify the endogenous drivers further. The results indicate the following. (1) China was a net exporter of industrial VW trade. The main VW export sectors in China were the manufacture of textiles and wearing apparel, paper products, and chemical products, which had the characteristics of high water consumption, high pollution, and low added value, respectively. (2) The net exports of industrial VW from China mainly went to the US, EU, ROW (rest of the world), and Japan. China's VW exports to the US and Japan are declining, while exports to the EU and Russia are increasing. (3) The decrease in the water-use coefficient in all industrial sectors in China was the most critical reason for inhibiting the increase in the country's industrial VW exports. The export structure effect of intermediate products, product structure effect of foreign final demand, and scale effect of foreign final demand were the primary reasons for the rise in VW exports, but all gradually diminished. Moreover, the structural effects of China on the use of domestic intermediate products had a significant positive effect on the increase in VW exports. In contrast, those of foreign products had an extremely weak effect. [ABSTRACT FROM AUTHOR]

To achieve food security goals, water accounting seems to be one of the most powerful tools to deal with water scarcity management. Thus, indicators, such as virtual water and water productivity, can be considered complementary rather than competing indicators to assess water demand efficiency use. Water computation is, therefore, a crucial tool to understand the overall tendency of water consumption and to assist the decision makers in their decisional process about water efficiency use in different phases of production. In this perspective, this paper aims to evaluate water use throughout the value chain of the olive oil sector, which is the first strategic agro-industrial sector in Tunisia. This evaluation will be undertaken while taking into account various crucial issues concerning the main two production phases in terms of the importance of water consumption (agriculture and processing phase). In the agriculture phase, the rainfed and irrigated modes will be compared, and in the processing phase, three different processing systems will be evaluated. Thirty surveys with farmers and nine surveys with olive oil mill owners were undertaken in the arid region of Sfax: one of the most important olive oil producers in Tunisia. The results show the importance of the theoretical framework adopted in clarifying the state of water consumption in a strategic sector, such as the Tunisian olive oil sector. In addition, the different calculated indicators highlight the importance of the application of a whole technical package and a controlled and efficient use of water to improve the economic profitability and the necessity to revise the irrigated olive growing extensions' policies under arid conditions. In addition, in the processing phase, the continuous-two phase system is emphasized as the most relevant system in terms of water efficiency use. This system is proposed to be encouraged by policy makers in future olive mill installations. [ABSTRACT FROM AUTHOR]