A spatial mismatch in water and arable land availability results in large virtual water transfers through interprovincial food trade in China. Accurately identifying and measuring water-saving links in interprovincial food trade can help to relieve water resources pressure in main grain-producing areas. We use a multiregional input-output table combined with the CROPWAT model to build China's interprovincial virtual water transfer network embedded in food trade in 2012. Then, water saving and scarce water saving are measured. Both consider the difference in water productivity among provinces, but the latter also pays attention to the scarcity of water resources. Finally, we adopt a water footprint to recalculate the scarce water savings without precipitation (green water). Our results indicate that the amount of virtual water transfer embedded in food trade is 74.9 billion m³, which is equivalent to 12.22% of the total water use in 2012. We observe large variations in the relationship between water resources abundance and agricultural water-use efficiency across provinces. Especially, there is a virtual water transfer from provinces with high water productivity but a lack of water to provinces with low water productivity but an abundance of water. The scarce water saving can identify sustainable food trade links, which can alleviate water scarcity in consuming provinces without exacerbating water shortage in producing provinces. In addition, interprovincial food trade results in 15 billion m³ of scarce gray water saving, which is equivalent to 59.76% of the scarce blue water saving. Scarce water saving based on blue water and gray water provides a basis for establishing an interprovincial compensation mechanism to balance the cost of water redistribution caused by food trade.

The argument that economies that face acute water scarcity problems can and should meet their water demand for food through cereal imports from water-rich countries; and that virtual water trade can be used to achieve water securities has become dominant in global water discussions. Analysis of country level data on renewable freshwater availability and net virtual water trade of 146 nations across the world shows that a country's virtual water trade is not determined by its water situation. Some countries have the advantage of high "economic efficiency" in food production and have surplus water, but resort to food import, whereas some water scarce countries achieve high virtual water trade balances. Further analysis with a set of 131 countries showed that virtual water trade increased with increase in gross cropped area. This is because of two reasons: First, when access to arable land increases, the ability to utilize available blue water for irrigation increases. Second, increasing access to arable land improves the access to water held in the soil profile as "free good", a factor not taken into account in assessing water availability. Hence, many of the humid, water-rich countries will not be in a position to produce surplus food and feed the water scarce nations; and virtual water often flows out of water-poor, land rich countries to land-poor water-rich countries. This means that "distribution of scarcity" and "global water use efficiency", are goals that are difficult to achieve through virtual water trade in a practical sense. For a water-poor, but land rich country, virtual water import offer little scope as a sound water management strategy as what is often achieved through virtual water trade is improved "global land use efficiency". The important policy inferences emerging from the analyses are two: First, assessing the food security challenges posed to nations in future purely from a water resource perspective provides a distorted view of the food security scenario. National policies on food security should take into account "access to arable land" apart from water availability. Second, analysis of water challenges posed by nations purely from the point of view of renewable water availability and aggregate demands will be dangerous. Access to water in the soil profile, which is determined by access to arable land, would be an important determinant of effective water availability.

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.

This paper analyzes virtual water trade flows through food products between India and its trading partners. It relies on the gravity model of trade and estimates a panel data fixed effect regression to identify drivers of virtual water trade. Our results show that India was the net exporter of virtual water in food products during 1990–2013; however later it turned out to be its net importer. Further our analysis shows distance between trading partners as the primary driver of virtual water trade. India prefers trading with its neighbours to reduce transportation costs. The availability of arable land and water used in crop production are limiting factors for production of food crops and thus act as essential factors in deciding the virtual water trade flows. These findings indicate that resource endowment factors influence bilateral virtual water trade flows.

In recent years, several global issues related to food waste, increasing CO2 emissions, water pollution, over-fertilization, deforestation, loss of arable land, food security, and energy storage have emerged. Climate change urgently needs to be addressed from an ecological and social perspective. Implementing new indoor urban vertical farming (IUVF) operations is one way to combat the above-mentioned issues as well as foodborne illnesses, scarcity of drinking water, and more crop failure due to infection from plant pathogens and insect pests. A promising production mode is plant factories (PFs), which are indoor plant production systems completely isolated from outside environment. This paper mainly focuses on the comprehensive review of scientific papers in order to analyse the different applications of urban farming (UF) based on three different dimensions: a) the manufacturing techniques and equipment used; b) the energy that these systems require, the distribution of energy, and ways to minimize the energy-related cost; and c) the technological innovations applied in order to optimize the cultivation possibilities of IUVF.

Water, energy, and food are essential and strategic resources for human well-being and socio-economic development and form the water-energy-food (WEF) system with competition and synergy. The competitive and synergistic evolution model was developed to remedy the limitations in quantitatively analyzing the tradeoffs and synergies of the WEF system. Firstly, an assessment model was developed for measuring the synergy and competition of the WEF system based on the order degree of each subsystem (That is, the development degree of each subsystem) and synergy theory. Then the synergy evolution model (SEM), with the help of a logistic model and accelerated genetic algorithm (AGA) model, was developed to measure and identify the steady-state. Furthermore, an empirical study was conducted with 30 provinces in China as examples. The results indicated that the food subsystem had the highest average order degree (0.347), followed by the energy subsystem (0.305), and the water subsystem had the lowest (0.281). The degree of order of the three subsystems exhibited an upward trend in time and has differences in the spatial distribution. Also, the results showed that synergistic, restrictive, and competitive relationships exist within the WEF system. Areas with competitive and restrictive relationships are mainly located in South China and North China, respectively, within the relationship between the water and energy subsystems. The entire country showed a restrictive relationship between the water and food subsystems. The energy and food subsystems showed that the eastern regions with relationship, while the western regions with competitive and restrictive relationship. Finally, effective measures (e.g., optimize the industrial structure, continuing to implement the strategy of “storing grain in the land and technology”, and to hold the arable land minimum) are suggested to achieve the WEF system coordinated and sustainable development. We believe that the assessment model is also applicable to assess the other complex and dynamic system worldwide that involve multiple factors.

Fresh water and arable land are essential for agricultural production and food processing. However, managing conflicting demands over water and land can be challenging for business leaders, environmentalists and other stakeholders. This paper characterizes these challenges as wicked problems. Wicked problems are ill-formed, fuzzy, and messy, because they involve many clients and decisions makers with conflicting values. They are also not solvable, but rather must be managed. How can agribusiness leaders effectively manage wicked problems, especially if they have little practice in doing so? This paper argues that a Community of Practice (CoP) and its tripartite elements of domain, community and practice can be effective in helping businesses manage wicked problems by focusing on the positive links between environmental stewardship and economic performance. Empirically, the paper examines three agribusinesses to assess the extent in which CoP is used as a strategy for sustainable water management.

A copula bi-level fractional programming (CBFP) method is developed for planning the water–food–energy–ecology (WFEE) nexus system. CBFP has advantages in (i) dealing with ratio-objective problems, (ii) balancing the conflicts between hierarchical decision levels, and (iii) reflecting joint risks of correlated uncertain variables. Then, a CBFP–WFEE model is formulated to the Ili-Balkhash basin in Central Asia, in which 108 scenarios associated with different irrigation efficiencies, ecological-flow demands (EBW), and water–land resources have been examined. Solutions of water allocation, hydropower generation, and land-use pattern are obtained. Our major findings are as follows: (i) from 2021 to 2050, water allocation to livestock in East Kazakhstan would remarkably increase (by 40.9%) when water allocation to food is satisfied; (ii) hydropower generation would increase with the rising ecological flows and arable land resources; (iii) EBW is the key factor influencing the water inflow to the Balkhash Lake; (iv) the share of ecosystem water allocation would exceed 17.5% by 2050, and grassland area would rank in the first place of the ecosystem. Compared with conventional bi-level stochastic programming and single-level fractional programming models, the CBFP–WFEE model can achieve a higher ecosystem service value and higher efficiency of water–land resources, which can provide more feasible and sustainable alternatives for the WFEE nexus system. The obtained results can help balance the contradictions among water shortage, economic development, and ecology protection, as well as provide synergic management strategies for regional sustainability.

Research on water cooperation in the Eastern Nile Basin has focused on expanding policy and diplomacy tools for a better allocation of transboundary water resources confined to the river. Regional cooperation on water and related sectors such as energy and land expands the bargaining and areas for mutual gain, and thus enhances cooperation perspectives. This paper looks at the contribution and the potential benefits of a regional cooperation approach to addressing the underlying challenges of water diplomacy, such as complexity and distrust. It also promotes the understanding of river basins as a “resource basin” of integrated and linked resource-use issues, not always related to the river flow. The paper provides an analysis of priority issues for water–energy–food nexus in regional cooperation in the Eastern Nile Basin. This basin represents an illustrative case for regional cooperation and increased integration due to multiple comparative advantages inherent in the uneven endowments of water, energy and arable land resources, and to varying levels of economic and technological advancement among the three riparian countries: Egypt, Sudan and Ethiopia. The paper also analyzes institutional arrangements on a regional scale, and elaborates on the inherent trade-offs associated with them.

Since the adoption of the open-door policy, the Chinese dietary pattern has changed greatly. Based on the dietary changes, this study analyzed the arable land and water footprints (WFs) for the food consumption of urban and rural residents in China. The results showed that the arable land demand and WFs for meat, vegetable oil, soybeans and liquor exceeded those for other foods, and the per capita arable land and WFs for food consumption of urban residents were higher than those of rural residents. The total arable land and WFs for the food consumption of residents increased by 16.9 million ha (from 91.1 to 108 million ha) and 214.5 billion m³ (from 457.9 to 672.4 billion m³), respectively, from 1983 to 2017. Specifically, the total arable land and WFs for the food consumption of urban residents increased by 45.9 million hm² (from 22.6 to 68.5 million hm²) and 318.3 billion m³ (from 113.2 to 431.5 billion m³), respectively. Additionally, those of rural residents decreased by 29.7 million hm² (from 69.2 to 39.5 million hm²) and 103.9 billion m³ (344.8 to 240.9 billion m³), respectively, mainly due to the migration of the rural population to cities and the reductions in per capita arable land and WFs due to increased crop yields. The arable land and blue WFs required for food consumption will reach 127.7 million hm² and 221.1 billion m³, respectively, in 2030. However, these values will be reduced by approximately 23% and 20%, respectively, to 98.9 million hm² and 177.8 billion m³ under a balanced dietary pattern. Measures such as improving the investment in agricultural research and development, advocating a balanced diet, and increasing the import of resource-intensive foods could alleviate the pressure on land and water resources.