Net Virtual Water Import Research Articles

Crop Water Use and a Gravity Model Exploration of Virtual Water Trade in Ghana’s Cereal Agriculture

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.

Understanding grain virtual water flux dynamics and drivers from a socio-ecohydrological perspective: A case study of landlocked developing countries of Africa

The virtual water (VW) approach offers a crucial heuristic tool to analyze water and food security by considering the water embedded in grain during the whole production process. African landlocked developing countries (LLDCs) continually suffer from an escalating food crisis and water resources and socioeconomic policy and water conservation strategy derived from the water-food nexus of virtual water trade (VWT) systems and resources may be the solution. Using a trade gravity model and multilateral data, this study evaluated grain VW flux patterns and 11 main drivers of VWT between 16 African LLDCs and their partners. Besides, the feedback path of VW flows corresponding to the socio-ecohydrological variability was studied using the impulse response function. The findings revealed that net virtual water import (VWI) varied across all 16 African LLDCs, ranging from 1.67 Bm3 to 10.28 Bm3 during 2000 and 2020, with an estimated yearly grain VWI of 105.61 Bm3. Green, blue, and grey water accounted for about 79.3%, 14.7%, and 5.98% of the total grain VWI, respectively. Ethiopia had the highest grain VWI among the African LLDCs. Grain VWI fluxes were significantly and positively driven by population growth and per capita GDP, which were expected to continue in the future. It was concluded that the quantitative analysis of grain VWT patterns and driving forces using the VW theory for LLDCs can be instrumental for guiding the socioeconomic policy and water conservation strategy. To effectively achieve sustainable water security and grain production, earmarked future VW strategy is required. Decision-makers should incorporate rational VW strategies and socio-ecohydrological factors into the monitoring system from a multidisciplinary perspective.

Assessment of Virtual Water Flows in Morocco’s Foreign Trade of Crop Products

As a semi-arid/arid country located in the northwest of Africa, Morocco is facing serious water scarcity driven by the dual stresses of decreasing availability of water resources and increasing water demands. Virtual water trade could be an effective tool to alleviate water scarcity. The paper presents an analysis of the relationships between agrarian productions, foreign trade, and the water sector in Morocco by deriving a comprehensive estimate of virtual water export and import in Morocco’s foreign trade of 40 crop products during the period from 2000 to 2017. Our objectives include determining the intensity of water consumption of exported and imported crop products and quantifying the water consumed and saved, respectively, by locally producing and importing these products. To this end, FAO’s Penman-Monteith climate model was used to estimate crop water requirements based on data on meteorological factors. The results show that Morocco was a net virtual water importer during the study period. The deficit was 595.74 Gm3. The tendency of total virtual water export was on a rising trend, while the total virtual water import was on a downward trend. The main exported virtual water was from vegetables (68.87 Gm3, 72.47%) and the main imported virtual water was from cereals (679.68 Gm3, 98.4%). Regarding crop product’s water intensity, we found that the exported crop products were excessively concentrated on water-intensive products such as mandarins and clementines, figs, oranges, apricots, plums, citrus fruits, olives, tomatoes, asparagus, peas, and artichokes. On the other hand, the agricultural policy of 2009–2020 increased the production of water-intensive products. This finding seems to be going against the virtual water trade theory, which states that water-poor countries should import water-intensive products and produce local products with lower water requirements.

A BPNN-based ecologically extended input-output model for virtual water metabolism network management of Kazakhstan.

In this study, a back-propagation-neural-network-based ecologically extended input-output model (abbreviated as BPNN-EIOM) is developed for virtual water metabolism network (VWMN) management. BPNN-EIOM can identify key consumption sectors, simulate performance of VWMN, and predict water consumption. BPNN-EIOM is then applied to analyzing VWMN of Kazakhstan, where multiple scenarios under different gross domestic production (GDP) growth rates, sectoral added values, and final demands are designed for determining the optimal management strategies. The major findings are (i) Kazakhstan typically relies on net virtual water import (reaching 1497.9 × 106 m3 in 2015); (ii) agriculture is the major exporter and advanced manufacture is the major importer; (iii) by 2025, Kazakhstan's water consumption would increase to [19322, 22016] × 106 m3 under multiple scenarios; (iv) when Kazakhstan's GDP growth rate, manufacturing's added value, and final demand are scheduled to 5.5%, 8.5%, and 5.8%, its VWMN can reach the optimum. The findings are useful for decision makers to optimize Kazakhstan's industrial structure, mitigate the national water scarcity, and promote its socio-economic sustainable development.

Revisiting the Concept of 'Virtual Water' in Light of the Impact of the Great Ethiopian Renaissance Dam on Egypt's Water Interests

Revisiting the Concept of 'Virtual Water' in Light of the Impact of the Great Ethiopian Renaissance Dam on Egypt's Water Interests Marwa Mamdouh-Salem (bio) Introduction Virtual water is one of the few concepts that serious disagreements have not been raised on its definition. Simply, it is the amount of water that is embedded in food or other products needed for its production. It also refers to the hidden flow of water if food or other commodities are traded from one place to another.1 Virtual water allows some countries to support other countries in their water needs. Instead of producing these goods themselves, the importing country can utilize this water for other purposes that else would have been necessary for its production. So, a water scarce country can import products that require a lot of water for their production rather than producing them domestically. By doing so, real water savings can be attained relieving the pressure on the water resources worldwide. Accordingly, several countries – such as Jordan, Israel, and the Gulf States – have consciously formulated policies to enable water saving by [End Page 12] reducing export of water-intensive products, notably crops. It is important to mention that the virtual water content of a product may inform about the environmental impact of consuming this product. By knowing the virtual water content of products, an awareness of the amount of water needed to produce a specific commodity is created. This informs us of the impact that some goods have on the water system. Moreover, the water volume results from the country's import of virtual water should be added to the total water use of the country, thus getting a picture of a nation's real call on the global water resources. Similarly, virtual water export should be subtracted from the volume of the country's water use. The sum of national water use and net virtual water import is known by the 'water footprint' of a country. This 'water footprint' can be a strong tool to show people their impact on the natural resources. The awareness of one's 'individual water footprint' aims to stimulate a more careful use of water. It may also be included in agricultural and industrial production plans and leads to more environment friendly trade policies.2 Ever since Tony Allan introduced an updated version of the concept 'embedded water' in the mid-1990s,3 virtual water trade has been subject to strong academic and scientific debate. This debate produced two main trends: The first trend – which is adopted by the majority – views virtual water as a fact of life exercised by the people since ancient times. The Old Testament tells us about the prophecy of Joseph on how "the seven years of plenty which were in the land of Egypt ended, and the seven years of famine began to come."4 Egyptians stored big quantities of food crops that they cultivated during the time of water abundance to compensate for the food shortage that will happen because of the seven years of drought. This is simply a 'water storing technique' based on the concept of virtual water. In this context, the logic of virtual water is: if the country does not have enough water to cultivate the needed food crops, then it can "import water." This can be done through the importing of crops and other food products from other countries that have water abundance.5 Therefore, this trend endorses the view that since virtual water is a reality, it is necessary to acknowledge [End Page 13] its existence and to start incorporating it – in a scientific way – into the state's national agricultural, economic, and trade strategies. The second trend is an attempt to think outside the virtual water's box as it tends to consider the political, economic, and social factors related to the cultivation of crops. Among the significant works that demonstrate this vision is Jessica Barnes who believes that water is not only limited to agricultural production; rather it should be seen as a more comprehensive process that involves people's lives. Rural environment is characterized by unique social and economic traditions and customs that control the peasants' lifestyle...

Virtual water transfers in Africa: Assessing topical condition of water scarcity, water savings, and policy implications

Africa is facing an increasing challenge with respect to water scarcity (WS), which is driven by climate change, population growth, and socioeconomic growth combined with inadequate water resources management. In particular, there is significant concern of virtual water (VW) trade, which plays the key role in water resource management and food security sustainability. Using bilateral trade data, this study consistently evaluated the change and balanced trade of major grains, the VW flows, WS status, water dependency (WD), water self-sufficiency (WSS), and water savings/losses within5 African sub-regions and their partners from 2000 to 2020. The ratio of water use to water availability was used to estimate the WS. The WD was quantified by the ratio of the net VW import to the regional water appropriation and the regional water savings/losses were also quantified by multiplying the inter-regional trade by the virtual water content of the imported/exported grains. The overall average trade deficit of African regions was found to increase to −1364.22 × 106 tons and Africa imported 41,359.07 Bm3 of VW from grain products. Green water contributed 79.33% of the total VWI. The WS values for East African countries were >100, indicating overexploitation. Besides, the overall WD in Africa was 465.5% for the studied period. The trade of main grains between Africa and the rest of the planet corresponded to a global water loss of 2820.7 Bm3·yr−1. However, the inter-continental cereal VW trade pattern and high trend will continue in the future. In view of the rising tension of WS, some African countries need to revise international crop trade and water resources conservation policies to promote a more balanced ecosystem. This study exemplifies that decision makers would consider VW flows and water savings/losses for enhancing water use efficiency and fair trading, thus increasing food production in Africa.

Identifying optimal virtual water management strategy for Kazakhstan: A factorial ecologically-extended input-output model

Virtual water is an important indicator measuring the amount of water needed from the perspective of consumption, which can help decision makers to identify desired system design and optimal management strategy against water resources shortage. In this study, a novel model named as factorial ecologically-extended input-output model (abbreviated as FEIOM) is developed for virtual water management. FEIOM integrates techniques of input-output model (IOM), ecological network analysis (ENA) and factorial analysis (FA) into a general framework. It is effective to evaluate the virtual water flows, reveal ecological inter-connections in virtual water system (VWS), and identify key water consumption sectors that have significant individual and interactive effects on VWS's performance. FEIOM is then applied to identifying optimal virtual water management strategies for Kazakhstan in Central Asia. The main findings are: (i) Kazakhstan is a net importer of virtual water (reaching up to 46.0 × 109 m3), demonstrating that the national economic structure is reasonable, which can abate the national water scarcity and improve its eco-environmental protection; (ii) the virtual water of agricultural sector is net exporter, where vegetables, fruits and nuts occupy 86% of the total agricultural exports; the massive export of water-intensive products further squeezes the water for other users; (iii) the key factors affecting the national VWS are agriculture > primary manufacturing > advanced manufacturing > services. Therefore, from solving water resources shortage and facilitating sustainable development perspectives, Kazakhstan should stimulate the domestic primary manufacturing productions and improve agriculture and advanced manufacturing water-use efficiencies.

Analysis of Virtual Water Trade Flow and Driving Factors in the European Union

The inefficient application of water resources has become an urgent problem restricting the world’s sustainable development. Virtual Water Trade opens a new perspective on improving water resource utilization efficiency. Based on a multi-regional input–output model and the logarithmic mean Divisia index, the virtual water flows between 2000–2014 in 43 countries and regions have been evaluated, and the driving forces of changes in virtual water flows for the European Union were revealed. During the study period, the total amount of virtual water flow continued to increase. The United Kingdom is a net virtual water importer that depends on the European Union significantly. There was a large amount of virtual water flow from the European Union to the United States during 2000–2012. However, China gradually seized the share of virtual water from European Union exports after 2012. Economic effects and virtual water intensity effects are the most significant drivers of virtual water flows. The difference is that the economic effect positively drives virtual water flows, while the virtual water intensity effect negatively influences. The results reveal the nature of the United Kingdom in the virtual water trade and can provide post-Brexit recommendations.

Understanding the two-way virtual water transfer in urban agglomeration: A new perspective from spillover-feedback effects

Interregional trade not only contributes to economic growth but also causes a large amount of virtual water transfer. The virtual water transfer brings about two-way impact of environmental stress between regions. It is essential to examine the two-way impact mechanism to achieve water sustainability. Interregional virtual water transfer includes three aspects of effects: multiplier, spillover and feedback effects. Among them, multiplier effect is the interaction in a single region. Spillover effect generally refers to the one-way impact of former region's economic development on latter region, while the feedback effect refers to the economic change of latter region in turn has an impact on the former region on the basis of the spillover effect. However, most studies have been focusing only on the one-way impact of virtual water transfer, which are the multiplier and spillover effects. This paper introduces a new spillover-feedback effects model to measure the two-way impact of virtual water transfer in urban agglomerations, and takes the Beijing, Tianjin and Hebei capital agglomerations in China as a specific case. The results illustrate that the spillover-feedback effects had significant contributions to virtual water transfer. From the perspective of regional scale, Beijing was a net importer of virtual water, with a net import volume of 1.019 × 108 m3. Tianjin and Hebei were net exporters of virtual water, with net exports of 0.069 × 108 m3 and 0.950 × 108 m3 respectively. The values of the feedback effect were large and should not be ignored, which accounted for up to 40% of the spillover effect. Furthermore, at the sectoral scale, the sectors with large ratios of spillover-feedback effects to total effects in regions included mining, agriculture, manufacturing and transportation. In Beijing, this ratio of mining exceeded 50%. Additionally, the effect intensity patterns were different from the effect patterns, which prove that the regional ability to stimulate water consumption was not consistent with the actual impacts. Finally, regions should pay more attention to managing the industries and enterprises with high virtual water export, adjust the trade structure, strengthen inter-regional cooperation and clarify regional responsibilities for water-saving. In a word, understanding interregional two-way impact mechanism is essential for the sustainable and collaborative development of the economy and environment in urban agglomerations.

A two-stage factorial-analysis-based input-output model for virtual-water quantification and metabolic-network identification in Kyrgyzstan

In this study, a two-stage factorial-analysis-based input-output model (TFA-IOM) is advanced for virtual water assessment, which integrates techniques of factorial analysis (FA) and ecological network analysis (ENA) into input-output model (IOM). TFA-IOM can not only identify the crucial water transaction sectors and the associated integral utility relationships, but also investigate the individual and interactive effects of multiple factors on virtual water metabolic network (VWMN) through measuring water consumptions of different sectors. The developed TFA-IOM is applied to Kyrgyzstan in Central Asia to quantify its virtual water and identify its metabolic network, where agricultural and animal husbandry sectors are the main water consumers. Our major findings are: (i) Kyrgyzstan is a country relying on net virtual water import (reaching up to 3,242 × 106 m3); (ii) WHT (wheat) is the main virtual water supplier (with 349 × 106 m3 virtual water to others); (iii) WHT, VGF (vegetables, fruit, and nuts), PFB (plant-based fibers), CTL (bovine cattle) and RMK (raw milk) are the main sectors affecting the VWMN (e.g., utility relationship and integral virtual water recycling index). From a long-term and sustainable development point view, stimulating Kyrgyzstan’s domestic WHT and RMK productions and improving VGF, PFB and CTL water-use efficiencies can facilitate reducing net virtual water import and promoting the mutualism degree of the national VWMN.

The Paradox of the Virtual Water Trade Balance in the Mediterranean Region

Climate change, water shortages and desertification threaten the economic and environmental sustainability in the Mediterranean. Limited rainfall and higher temperatures put agricultural production, which relies on water availability, in jeopardy. Thereupon, Mediterranean countries pursue agri-food resilience and water preservation through efficient water policies. Hence, water-deprived areas ought to import rather than produce water-intensive products to maintain water inventories and sustainability consequently. As this study examines the water sustainability for a Mediterranean water-scarce region with a particular focus on agriculture, the virtual water trade balance explores this hypothesis. A regional input–output model is constructed, and then total water consumption and the virtual water flows for each economic sector are estimated to determine the virtual water trade balance of the economy. Results indicate that the study area has a trade deficit and struggles economically but is a net importer of virtual water and secures water sustainability. As this virtual water deficit relies heavily on agriculture and originates in vast total water consumption rather than a large trade deficit, a paradox occurs; water-intensive cultivations and animals that consume 91.75% of water resources end up appearing to be water-saving. Further research is needed to strike a balance between economic growth and environmental protection.

Virtual Water Trade as a creative water-saving technique

Understanding the idea and strategy of virtual water trade is critical for formulating informed policies to increase water usage efficiency at various levels. The implementation of the concept of virtual water as a creative water-saving technique in Egypt, however, is still in need of comprehensive testing, research, and feasibility evaluation. Egypt also requires extensive investigations, surveys, and feasibility evaluations. At present, as a percentage of water supplies, Egypt's net virtual water import has risen to 23.55 percent. The primary concern here is to apply virtual water as a strategy that meets the interests and goals set out in Egypt's National Water Management Plan. The key concern of this paper is investigating the general use of virtual water as a water-saving technique in Egypt. It outlines the water scarcity problem and its indicators, supply and demand for water resources in Egypt, and water scarcity forces in Egypt. Going to virtual water in economic ideas history, the definitions of virtual water and water footprint, then virtual water as an analytical instrument and a political strategy. Finally, water saving from virtual water trade and its advantages and disadvantages in Egypt. In order to follow the introduction of the virtual water definition in the national water management policy of Egypt, A clear vision and understanding of its advantages and disadvantages according to the conditions of Egypt is required. Further analysis and a thorough understanding of the impacts and experiences on the local social, economic, environmental, cultural, natural and political situation is needed for this new definition as a policy choice in Egypt.

Non-negligible regional differences in the driving forces of crop-related water footprint and virtual water flows: A case study for the Beijing-Tianjin-Hebei region

Water scarcity is a significant risk for meeting increasing food demand around the world. The importance of identifying the driving forces behind water consumption in agriculture and relative virtual water (VW) flows has been widely reported in order to provide practical advice for regional sustainable agricultural water resource management. However, the differences of regional driving forces behind both water consumption and VW flows were largely ignored. To fill the crucial gap, taking nine major crops grown in the Beijing-Tianjin-Hebei (BTH) region in China over 2000–2013 as the study case, we investigated the regional differences in socio-economic driving forces on both the estimated water footprint (WF) in crop production and relative inter-city VW flows for each crop per year. Results show that although there is little change in total WFs in crop production (∼43.3 billion m3/y on annual average), the WF per unit mass of crop decreased and the crop structure in the total WFs changed greatly. The BTH region was a VW importer with net VW import of 11.7 billion m3/y by 2013 but the roles of each cities were different. Inter-city VW was predominantly exported from the southern regions. The per capita GDP was the main positive driver of both total WFs and relative VW flows. Whereas economic productivity and consumption capacity were inhibiting factors for the WFs and VW flows, respectively. The levels of total crop WFs in agricultural cities were more sensitive to the effects of the main driving factors. The intensity of driving factors behind the inter-regional crop-related VW flows was shown to be directly related to regional role as an importer or exporter. Aiming for a balance between water sustainability, food security and economic developments, the current analysis suggests characteristic-based agriculture in terms of regional differences in water consumption and local roles in relative inter-regional VW flows. Especially for agricultural cities which are VW exporters, reducing water consumption per unit agricultural product and increasing economic production value per drop of water used in all sectors are equally important.

Virtual water flows, water footprint and water savings from the trade of crop and livestock products of Germany

AbstractComprehensive assessment of the virtual water trade of Germany with the world is performed and the national water footprint through the trade of crop and livestock products from 1991 to 2016 is assessed. Virtual water flows based on 328 products with more than 200 countries indicate Germany as a net virtual water importer. Average virtual water import was 100.5 Bm3/y, virtual water export was 60.2 Bm3/y and net virtual water import was 40.3 Bm3/y. Trade patterns of virtual water transfer differ for the various commodity types. Trade between Germany and the world implies a global water loss of 5.9 Bm3/y. This study portrays that trade between countries is not only related to the economics but interlinked with the agricultural water use and management practices of the respective nations. Sustainable management of the resources will require a collective consideration of the agricultural, water and economic sectors while developing strategies.

Analysis of Water Resources Carrying Capacity of the “Belt and Road” Initiative Countries Based on Virtual Water Theory

Most countries along the route of the “Belt and Road” initiative are faced with a shortage of water resources. However, successful implementation of the initiative depends on water availability to support economic and social development. We designed a water resources carrying capacity evaluation index system, assigned grades and weights to each evaluation index and calculated a water resources carrying index for the 65 countries along the route. We used virtual water theory to analyze China's net virtual water import from key bulk agricultural products through international trade. For more than half of the countries along the route, their water resources will be unable to support the economic development that will be necessary for fulfilling the goals of the Initiative. As a country with insufficient water resources carrying capacity, China is a net virtual water importer in the virtual water trade. This virtual water trade can improve China's water resources support capacity, and ensure China's water and food security for the future.

Virtual Water Flow and Water Footprint Assessment of an Arid Region: A Case Study of South Khorasan Province, Iran

Water challenges—especially in developing countries—are set to be strained by population explosion, growing technology, climate change and a shift in consumption pattern toward more water-intensive products. In these situations, water transfer in virtual form can play an important role in alleviating the pressure exerted on the limited water resources—especially in arid and semi-arid regions. This study aims to quantify the 10-year average of virtual water trade and the water footprint within South Khorasan—the third largest province in Iran—for both crops and livestock products. The virtual water content of 37 crops and five livestock is first estimated and the water footprint of each county is consequently measured using a top-down approach. The sustainability of the current agricultural productions is then assessed using the water scarcity (WS) indicator. Results of the study show that in spite of the aridity of the study area, eight out of 11 counties are net virtual water exporters. Birjand—the most populous county—is a net virtual water importer. The 10-year average water footprint of the region is measured as 2.341 Gm3 per year, which accounts for 2.28% of national water footprint. The region’s average per capita water footprint however, with 3486 m3, is 115% higher than the national ones. Crop production and livestock production are responsible for 82.16% and 17.84% of the total water footprint. The current intensive agricultural practices in such an arid region have resulted in a water scarcity of 206%—which is far beyond the sustainability criteria. This study gives the water authorities and decision-makers of the region a picture of how and where local water resources are used through the food trade network. The generated information can be applied by the regional policymakers to establish effective and applicable approaches to alleviate water scarcity, guarantee sustainable use of water supplies, and provide food security

Measuring and Analyzing the Specific Water Demand for Agricultural Products and the Position of Iran in Trade with other Countries

Water resources management and use in agriculture are important due to the scarcity of water and soil resources and the increasing demand for food because of population growth. Therefore, the purpose of this study is to evaluate the volume of water exported and imported in the form of agricultural products trade. For this purpose, the technical-baseline approach has been used to measure virtual water and special water demand of trade for 36 crops and garden products has been calculated for the period 2001-2015. The results showed that Iran was a virtual net water importer in the agronomy crops in the mentioned years and a virtual net water exporter in the garden products. In general, iran was net virtual water importer. On average, Iran exported 4.3 billion cubic meters of annual crops and 15.8 billion cubic meters of imported water annually through trade in crops and garden products. Among crops and garden products, legumes and pulses are the most widely consumed crops based on their estimated specific water demand. The results provide some information that can be used to optimize the commercial mix of agricultural products to conserve water resources and ensure food security.

A dynamic view on agricultural trade patterns and virtual water flows in Peru

Increasing integration in global markets can foster economic growth, but also impacts the use of water resources for the production of traded goods. This is particularly critical for low-and middle-income countries where increasing agricultural exports, especially of high-value horticultural products such as fresh fruits and vegetables is promoted as a pro-poor development strategy. The aim of this paper is to quantify the contribution of agricultural trade to virtual water flows and economic gains. The focus is on Peru and trade flows since 1986, as this represents a case of rapidly increasing trade flows and a rapidly changing product composition of trade. We consider long-term trade trends and changes in the product composition of trade, using a product classification, and analyze the implications for trade revenues, VW flows, blue and green water use, and economic water use efficiency. We use an innovative decomposition analysis to disentangle the drivers behind increased virtual water exports. We find that despite sharp increase in agricultural exports Peru is a net importer of virtual water, which implies that participation in international trade has been conducive for both economic growth and saving water resources at national level. We find agricultural exports to have a high economic water efficiency but to increase water scarcity and the use of blue water in producing regions. Our results imply that a focus on high-value export sectors is a valid development strategy for low- and middle-income countries from both an economic and a water perspective but that the strategic location of export production with respect to the availability of water is important for policy-makers to consider. Our approach confirms the importance of considering long-term dynamics and regional differences in research on virtual water trade.

ECONOMIC AND ENVIRONMENTAL STUDY FOR OPTIMAL CROP PATTERN IN THE LIGHT OF THE EXPECTED WATER RESTRECTIONS

The agricultural area in Egypt is the largest consumer of water and still requires more water to expand. Any changes in Nile water supply due to climate change would threaten the agricultural water productivities, both physical productivity and economic productivity, and the food security in Egypt. The objective of the current paper is to investigate the impacts of Nile supply reduction on the agricultural water productivities and food security in Egypt using the Agriculture Sector Model in Egypt (ASME). The results showed that the reduction in Nile supply will either increase or decrease the areas of different crops, and generally will decrease the total cropped area. Regarding the food security, all indicators refer to a slight decline in the food security progress in terms of reduction of water availability, self-sufficiency of strategic food crops, and net virtual water import. The reduction in Nile supply will also deteriorate the economic situation, which can be confirmed by the reduction in agricultural productivity, consumer-producer surplus, and number of jobs as well as the increase in net imports’ value and water marginal value. The current study recommends implementing adaptation measures to efficiently use the available water resources and to increase the agricultural productivity per unit area.

Assessment of Water Footprints of Consumption and Production in Transboundary River Basins at Country-Basin Mesh-Based Spatial Resolution.

Water is unevenly distributed globally. This uneven distribution is the reason behind the differences among geographical areas in terms of their water footprint of consumption and production. This gives the global trade of goods a unique feature. This characteristic of the water footprint might be used to address water scarcity and conflicts because water availability also has the same trend. Transboundary river basins are freshwater resources with a high probability of water scarcity and conflict because the water is claimed by multiple sovereign countries. In order to design sharing mechanisms for transboundary river basins that incorporate virtual water concept, it is key to identify the virtual water balance of country-basin units. A study addressing this research gap is not yet available. This article identified and discussed net virtual water importer and exporter sub-basins of transboundary rivers at a country-basin mesh based spatial resolution. The results of our study show that out of the 565 country-basin units surveyed in this article 391, 369, and 461 are net gray, green, and blue virtual water importers respectively. These sub-basins covers 58.37%, 47.52% and 57.52% of the total area covered by transboundary river basins and includes 0.65, 1.9, and around 2 billion people, respectively. The results depict that not only the water endowment of sub-basins is a determining factor for their water footprint of consumption and production, but also their social, economic, and demographic profiles. Furthermore, the water footprint of consumption and production within most of the country-basin units have a global feature. Hence, sustainable water management schemes within border-crossing basins should take into account not only the local but also the global water footprints of consumption and production. This can offer more options for sharing transboundary river basins water capital, thereby minimizing the probability of water scarcity and water conflicts.