Virtual Flows Research Articles

Mitigating trade-driven water scarcity via water-saving irrigation in China: Different role of surface water and groundwater

Examining virtual water flows in China, we identified a crucial gap in differentiating between groundwater (GW) and surface water (SW). Understanding the unique roles of virtual GW and SW is vital for local sustainable water use. We firstly track virtual GW and SW flows via inter-provincial trade, using a comprehensive inventory that included GW and SW uses in China. Our findings show nearly two-thirds of Chinese provinces face GW or SW scarcity in 2017, with about 34 % of GW and 31 % of SW use driven by interprovincial trade. Water rich regions acted as virtual SW exporters, while water scarce regions served as virtual GW exporters. Targeted irrigation efficiency improvement strategies, considering regional surface and groundwater pressures, could notably reduce interprovincial trade-driven GW and SW use by 12 % and 7 %. It's crucial to manage GW and SW as single resources, recognizing both their physical and virtual distinctions in local water use.

Urban sector land use metabolism reveals inequalities across cities and inverse virtual land flows

Urban land is the primary scene for manufacturing and services providing, through which the economic activities and trade flows amplify and cascade, interacting the natural and human systems. However, our understanding of the spatial pattern, remote drivers, and coupled interwoven linkages of economic sectoral land use within and among cities remains inadequate. Here, we establish a novel sectoral urban land use inventory and a virtual land flow network for 13 cities in the Jing-Jin-Ji region in China to understand urban land use metabolism. Results show highly mixed distribution patterns of urban sectoral land use. Moreover, spatial heterogeneity exists among industries and across spatial scales. Urban virtual land flow presents inverse directions compared to agricultural land. Results also reveal inequalities in benefit-cost and supply chain networks across cities, and a wide range of control and exploitation relationships in the region. Our results suggest that Beijing and Tianjin, as main beneficiaries in the regional economic network, are responsible for collaborating intensively in Jing-Jin-Ji region and will be key in promoting sustainable development.

Assessing global agri-food system exceedance of national cropland limits for linking responsible consumption and production under SDG 12

Sustainable Development Goal (SDG) 12 requires countries to achieve responsible consumption and production patterns without exceeding safe environmental limits for natural resource use. This is particularly relevant to the global agri-food system, a major contributor to the exceedance of environmental limits such as cropland (a major component of the land-system change planetary boundary). However, little is known about how virtual cropland flows embedded in agri-food commodities jointly impact national consumption- and production-based environmental limits for cropland use in the context of responsible agri-food consumption and production. Using a multi-regional input-output model and cropland limits of agri-food consumption and production, we identified specific countries and commodity supply chains that contribute to the exceedance of production-based cropland limits of producer countries (both domestic and via trade), irrespective of whether their own consumption-based cropland limits are exceeded. For example, 86% of China's consumption-based cropland footprint originated from regions that exceeded their production-based cropland limits, even though China's per capita consumption footprint is within safe fair-share limits. This occurred mainly due to the consumption of domestically produced and imported commodities such as oilseeds, cereals, and fruit and vegetables. In addition, we identified patterns in international trade relationships that could inform national-level responsible agri-food consumption/production interventions across the global supply chain, thereby contributing to SDG 12. More stringent regulations and improved policies are required to reduce the exceedance of consumption-based and production-based environmental limits and avoid exceeding the global land-system change planetary boundary.

Virtual water flows of Turkey's agricultural products: A gravity approach

In this study, we use a gravity model to analyze virtual water flows due to the trade of agricultural products for Turkey. We calculate virtual water flows of agricultural trade for 326 products and 192 trade partners for 2002–2019. The empirical model of virtual water trade flows for Turkey is formed where the dependent variable is the total amount of water embedded in the trade of agricultural products. Besides the baseline equations, which include conventional explanatory variables like income, population, geographical distance, and affinity dummies, we estimate expanded models that include two measures of water availability and two measures of water pressure. Additionally, variables showing the size of agricultural activity and availability of agricultural land in the partner country are included in the analysis. Furthermore, the gravity models for total virtual water flows are disaggregated into intermediate and consumer goods, providing further insights.

City‐Level Virtual Groundwater Flows in Northern China and the Effect of Agricultural Relocation on Alleviating Groundwater Scarcity

AbstractNorth China faces severe groundwater overdraft because of unsustainable groundwater use. However, consumers of local groundwater have rarely been precisely delineated. As such, identifying external consumers of groundwater‐intensive products may promote targeted policies from the consumption side, especially for the most water‐scarce Beijing‐Tianjin‐Hebei (BTH) metropolitan area, which has important links to food security and groundwater overdraft across North China. In this study, we revealed the prefecture city‐level virtual groundwater flows in the BTH region for, to our knowledge, the first time by compiling a nested multiregional input‐output table with 13 BTH cities and 28 Chinese provinces outside BTH in 2012. Our results showed that >50% of groundwater use in BTH cities was driven by agricultural supply for outside provinces, significantly exceeding the local demand of 38.8%. In addition, we simulated different scenarios that focused on redistributing the original agricultural production of the BTH region to other northern provinces. We found that these redistribution strategies would lead to 13%–67% groundwater savings relative to total groundwater use in the BTH region in 2012. Moreover, our results also indicated that BTH cities would save groundwater under higher stress in exchange for increased groundwater use in provinces under lower stress. These findings can be utilized to optimize the agricultural distribution and groundwater conservation policies in other regions or countries facing agriculture‐induced groundwater overdraft issues.

Large Virtual Transboundary Hazardous Waste Flows: The Case of China.

The Basel Convention and prior studies mainly focused on the physical transboundary movements of hazardous waste (transporting waste from one region to another for cheaper disposal). Here, we take China, the world's largest waste producer, as an example and reveal the virtual hazardous waste flows in trade (outsourcing waste by importing waste-intensive products) by developing a multiregional input-output model. Our model characterizes the impact of international trade between China and 140 economies and China's interprovincial trade on hazardous waste generated by 161,599 Chinese enterprises. We find that, in 2015, virtual hazardous waste flows in China's trade reached 26.6 million tons (67% of the national total), of which 31% were generated during the production of goods that were ultimately consumed abroad. Trade-related production is much dirtier than locally consumed production, generating 26% more hazardous waste per unit of GDP. Under the impact of virtual flows, 40% of the waste-intensive production and relevant disposal duty is unequally concentrated in three Chinese provinces (including two least-developed ones, Qinghai and Xinjiang). Our findings imply the importance of expanding the scope of transboundary waste regulations and provide a quantitative basis for introducing consumer responsibilities. This may help relieve waste management burdens in less-developed "waste havens".

Physical and virtual nutrient flows in global telecoupled agricultural trade networks

Global agricultural trade creates multiple telecoupled flows of nitrogen (N) and phosphorus (P). The flows of physical and virtual nutrients along with trade have discrepant effects on natural resources in different countries. However, existing literature has not quantified or analyzed such effects yet. Here we quantified the physical and virtual N and P flows embedded in the global agricultural trade networks from 1997 to 2016 and elaborated components of the telecoupling framework. The N and P flows both increased continuously and more than 25% of global consumption of nutrients in agricultural products were related to physical nutrient flows, while virtual nutrient flows were equivalent to one-third of the nutrients inputs into global agricultural system. These flows have positive telecoupling effects on saving N and P resources at the global scale. Reducing inefficient trade flows will enhance resource conservation, environmental sustainability in the hyper-globalized world.

Present and future perspectives of blockchain in supply chain management: a review of reviews and research agenda

A growing number of papers addressing blockchain to supply chain management has been found, extending the range for scholars and practitioners aiming to comprehend the state of the art is in this emerging field. Thus, we depict the current state of the art of blockchain in supply chain management and identify the main gaps to be explored in order to advance knowledge in this interplay. We employ the systematic literature review approach in a review of reviews to look into 103 review papers found in peer-reviewed scientific journals currently assigned to Scopus or Web of Science databases. Our results extend the discussion through an integrative approach that embraces blockchain technology in the context of supply chain management from multiple perspectives, encompassing the interface between physical and virtual flows beyond one-step-back and one-step-forward scope. We also consider disruptive aspects of blockchain technology as an alternative to integrate different supply chain stakeholders and provide information sharing to support both process-monitoring and decision-making in different industries and segments.

The inter-provincial trade inequality in China: An assessment of the impact of changes in built-up land and carbon storage

Inter-regional trade contributes to the expansion of built-up land and carbon storage loss, which results in inequality in unequal exchange. Revealing this inequality can help socio-environmental sustainability be better achieved. This paper uses a multi-regional input-output model to analyze the virtual built-up land flows embodied in the inter-provincial trade in China, and calculates the carbon storage loss caused by the expansion of built-up land. The inter-provincial trade inequality in China is discussed subsequently. The results show that regional unfair trade exists in China, and less developed regions are in an inferior position. Compared to less developed regions, developed regions obtain more benefits from inter-provincial trade, in both economic and environmental aspects. Regionally, the expansion of built-up land mainly occurs in the eastern and southern regions, which lost much carbon storage, especially Guangdong and Yunnan. Coastal regions had a high built-up land utilization efficiency, followed by the central regions. The built-up land interactions are mainly concentrated in the central and eastern regions, and the degree of trade participation in less developed regions is low.

3D U-Net Segmentation Improves Root System Reconstruction from 3D MRI Images in Automated and Manual Virtual Reality Work Flows.

Magnetic resonance imaging (MRI) is used to image root systems grown in opaque soil. However, reconstruction of root system architecture (RSA) from 3-dimensional (3D) MRI images is challenging. Low resolution and poor contrast-to-noise ratios (CNRs) hinder automated reconstruction. Hence, manual reconstruction is still widely used. Here, we evaluate a novel 2-step work flow for automated RSA reconstruction. In the first step, a 3D U-Net segments MRI images into root and soil in super-resolution. In the second step, an automated tracing algorithm reconstructs the root systems from the segmented images. We evaluated the merits of both steps for an MRI dataset of 8 lupine root systems, by comparing the automated reconstructions to manual reconstructions of unaltered and segmented MRI images derived with a novel virtual reality system. We found that the U-Net segmentation offers profound benefits in manual reconstruction: reconstruction speed was doubled (+97%) for images with low CNR and increased by 27% for images with high CNR. Reconstructed root lengths were increased by 20% and 3%, respectively. Therefore, we propose to use U-Net segmentation as a principal image preprocessing step in manual work flows. The root length derived by the tracing algorithm was lower than in both manual reconstruction methods, but segmentation allowed automated processing of otherwise not readily usable MRI images. Nonetheless, model-based functional root traits revealed similar hydraulic behavior of automated and manual reconstructions. Future studies will aim to establish a hybrid work flow that utilizes automated reconstructions as scaffolds that can be manually corrected.

The “Gravity” for global virtual water flows: From quantity and quality perspectives

The virtual water trade (VWT) has been proposed as a means of balancing national water budgets while also saving water globally. Since humans require both sufficient quantity and quality of water, the drivers of VWT flows should be thoroughly examined, including its three components. Multiregional input–output (MRIO) and gravity methods are used to investigate the influence of multiple factors on the green, blue, and grey water trading flows among 177 countries in 2014. Several factors were found to be strongly correlated with the grey water trade, offering valuable insight into water resource management, especially about water pollution. The findings verify the driving effects of socio-economic status and agricultural activities on virtual water trade. The study shows that the influence of water resources endowment on the virtual water trade flow is relatively small compared to economic structure in determining virtual water trade flows. The paper contributes to the research on the interaction between virtual water trade and various factors, which can assist decision-makers in optimizing economic structure by integrating water quantity and quality factors and realize sustainable management of water resources.

Virtual Carbon Flow in China’s Capital Economic Circle: A Multi-Regional Input–Output Approach

The Capital Economic Circle (CEC) is the area with the largest economic aggregate in northern China and has a strong status in driving the economic development of China. However, the industrial structure dominated by high energy consuming industries leads to a large number of carbon dioxide emissions, and the imbalance between economic development and carbon emissions in CEC is serious; therefore, it is necessary to explore how to solve the carbon imbalance problem of the CEC by relying on interregional cooperation. Based on China’s multi-regional input–output tables of 2012, 2015 and 2017, this paper proposes the CEC carbon-extended, multi-regional input–output model to measure virtual carbon flow and analyze how the industrial structure leads to the imbalance of carbon flow distribution in CEC. Indicators such as direct carbon emission coefficients, complete carbon emission coefficients and carbon emissions pull coefficients of the industrial sectors in CEC are calculated and the physical carbon emission and virtual carbon flows among the industrial sectors and the regions are evaluated. The results show that there are potential constraints from the uncoordinated configuration of industrial innovation chains among the CEC, and the “carbon imbalance” of CEC is mainly reflected in the backward production technology of Hebei and its inefficient connection with the industrial innovation chain of Beijing and Tianjin. It is suggested that policymakers should promote the low-carbon production system and strengthen green energy development and utilization to enhance green development in CEC. In future research, we should pay attention to the updating method of the input–output table and the development of carbon circular networks. This study has implications for some areas of China and developing countries in Asia, which also have an imbalance between industrial economy development and carbon emissions, and a similarity in space structure and industry layout with CEC.

Interregional flows of virtual cropland within China

Cropland is an essential resource for agricultural system and greatly impacts agricultural sustainability. Cropland can be embodied in the goods and transferred among regions. Managing cropland as a virtual resource, similar with virtual water strategy, is an effective measure to achieve sustainability. Therefore, it is of significance for policymakers to understand how virtual cropland transfers in the economic society. This study employed a Multi-Regional Input-Output model with high resolution in the agriculture sectors (nine categories of crops) to examine the interregional flows of virtual cropland within China in 2015. The results show that Heilongjiang, Inner Mongolia, and Jilin contributed the most virtual cropland, while Guangdong, Zhejiang, and Shandong were the largest receivers. The largest flow was from Heilongjiang to Guangdong embodied in cereals. Most of virtual flows were embodied in cereals, followed by sugar crops, other crops, legumes, and vegetables. Heilongjiang, Xinjiang, and Guangxi dominated the virtual outflows embodied in legumes, fruits, and oilseeds, respectively. This study is informative and implicative for policymakers to understand the spatial transfer pattern of virtual cropland, identify the key nodes, and design the effective measures to achieve sustainability.

RETRACTED: Hybrid neural networks with virtual flows in in medical risk classifiers

This article has been retracted. A retraction notice can be found at https://doi.org/10.3233/JIFS-219433.

The pattern of virtual water transfer in China: From the perspective of the virtual water hypothesis

Limited and uneven distributed water resources have become one of the main obstacles to China's sustainable development, and the “virtual water hypothesis” (VWH) is expected to help mitigate water stress. This study discusses the virtual water transfer pattern and water resources stress in China from the VWH perspective. Economic sectors in China are divided into land-dependent sectors and non-land-dependent sectors according to their dependence on specific local land types. Furthermore, the water resources withdrawal and utilization corresponding to these sectors are divided into land-dependent water resources (LDW) and non-land-dependent water resources (NLDW). Results show that the virtual LDW flows from economically poor to relatively developed regions, while the virtual NLDW flows in the opposite direction. LDW dominates Chinese water stress (78.2%) and virtual water flow (74.5%). Furthermore, the virtual water dominated by LDW ameliorates national water stress (the population under unsustainable water stress declined by 0.21 billion) but aggravates the imbalance of water resources between North and South. The transfer of virtual NLDW alleviates this imbalance slightly. Suitable land conditions play a decisive role in LDW withdrawal, which then cannot be replenished by virtual water. However, the withdrawal and transfer of NLDW are flexible, which should be a focus. The results point out that the possibility of water-rich regions as virtual water exporters is the key to alleviating the North–South water resource imbalance in China with VWH theory. Improvement of land productivity and water efficiency can be helpful to alleviate water stress. These findings may provide new insight into China's virtual water transfer pattern from the VWH perspective.

Volume versus value of crop-related water footprints and virtual water flows: A case study for the Yellow River Basin

Blue water (irrigation water) and green water (rainwater) constitute the indispensable inputs in crop production, and they virtually flow through crop trade. The valuation of water for crops is becoming essential for providing not only guidance in measuring both the biophysical and economic sustainability of agricultural water resources but also crucial information for investors and authorities engaged in water allocations. However, valuation of green water has been severely disregarded. Here, taking the Yellow River Basin as the study case, we show the feasibility of estimating the value of green water for crop production considering the costs in production processes in addition to blue water valuation. Thus, the volume versus value of blue and green water consumed in crop production as well as that of corresponding virtual water (VW) flows related to crop transfers within the basin are comparable. Fourteen major crops in current three typical years and four scenarios for the year 2050 under climate-socio-economic changes are examined. Results show that value of blue water was approximately 3 times that of green water for irrigated crops, whereas at similar level to the value of green water for rain-fed crops. Visible trade-offs between the regional volume and value of water used in crop production and that of the intra-national VW flows exist in terms of magnitude in time and space, as well as the structure by crops. The total volumes of the water footprint (WF), i.e., water consumption, in crop production and VW exports changed little over years, however the corresponding total water values was tripled and seven-folded, respectively, due to apple production expansions. Wheat was the biggest contributor in volume of VW export while apple accounted the most in value of VW export of the basin. The considered scenarios for 2050 suggested that the reduced values of crop-related WF and VW flows were more sensitive than the corresponding water quantity. This study implies the importance of managing the internal trade-offs or mutual effects between water resources and economic returns.

Pressure-Leak Duality for Leak Detection and Localization in Water Distribution Systems

Water utilities are challenged to reduce their water losses through detecting, localizing, and repairing leaks as quickly as possible in their aging distribution systems. In this work, we solve this challenging problem by detecting multiple leaks simultaneously in a water distribution network for the Battle of the Leak Detection and Isolation Methods. The performance of leak detection and localization depends on how well the system roughness and demand are calibrated. In addition, existing leaks affect the diagnosis performance unless they are identified and explicitly represented in the model. To circumvent this chicken-and-egg dilemma, we decompose the problem into multiple levels of decision-making (a hierarchical approach) where we iteratively improve the water distribution network model and so are able to solve the multileak diagnosis problem. First, a combination of time series and cluster analysis is used on smart meter data to build patterns for demand models. Second, point and interval estimates of pipe roughnesses are retrieved using least squares to calibrate the hydraulic model, utilizing the demand models from the first step. Finally, the calibrated primal model is transformed into a dual model that intrinsically combines sensor data and network hydraulics. This dual model automatically converts small pressure deviations caused by leaks into sharp and localized signals in the form of virtual leak flows. Analytical derivations of sensitivities with respect to these virtual leak flows are calculated and used to estimate the leakage impulse responses at candidate nodes. Subsequently, we use the dual network to (1) detect the start time of the leaks, and (2) compute the Pearson correlation of pressure residuals, which allows further localization of leaks. This novel dual modeling approach resulted in the highest true-positive rates for leak isolation among all participating teams in the competition.

Uncovering the patterns and driving forces of virtual forestland flows in China

Nowadays, virtual land use related to consumption and trade flows has become an important part of land use. However, there has been little discussion about virtual forestland use. Therefore, this study performs the multi-regional input-output model on virtual forestland use and its changes in thirty provinces in China. And the influencing factors behind the dynamics of virtual forestland have been explored through the structural decomposition analysis. The results show that the area of virtual forestland embodied in trade was 673,277 km2 and 566,791 km2 in 2007 and 2012, equivalent to 32.14% and 27.03% of the total forestland area in China, respectively. There was north to east coast virtual forestland trade mode in China. The developed provinces or cities in China such as Shanghai, Beijing, Tianjin and Guangdong have a disproportionate share of virtual forestland imports (over 90%) from least developed provinces and forest-rich provinces. In addition, 11.06% and 7.47% of China's total forestland in 2007 and 2012 was used to supply consumption of foreign countries and regions. In addition, forestland use intensity and consumption volume were the main reasons for the dynamic changes of virtual forestland in most provinces. Through the exploration of the virtual forestland flow pattern helps to develop forestland conservation and restoration policies from the consumer side and achieve sustainable development of China's forest land.

РОЗВИТОК ІНФРАСТРУКТУРНОГО ЗАБЕЗПЕЧЕННЯ СВІТОВОГО РИНКУ ЕЛЕКТРОННОЇ ЛОГІСТИКИ

The article states that the priority features of the current stage of globalization are informatization, electronicization and logistics of international business, which acts as the latest stage of integration of the world economy, the content of which is to expand virtual flows of resources, resulting in intensified competition in global electronic markets, deepening of interconnections between national economies at the level of social reproduction processes, formation of integrated logistics and electronic networks and their infrastructure. On the basis of the conducted generalizations the state establishments (ministries, departments, etc.), subjects of economic activity forming public infrastructure of the international market of electronic logistics, at cotton enterprises, TNCs, FIGs, etc.), consumers of products / services (individuals), partners (intermediaries), and in its structure the most priority segments are “business business” (B2B) “business consumer” (B2C). On the basis of certain patterns of development of the global e-logistics market, scientific and methodological approaches to the study of the development of infrastructure of national e-logistics markets are substantiated by the criteria: perfection of regulatory support, development of e-business; the state of development of the IT sector; optimality of the segment structure of outsourcing of the electronic logistics market; efficiency of the existing state of infrastructural support of development of the national market of electronic logistics. This allows you to create an information and analytical base to adjust the priorities of the national e-logistics business at the state level.)

Future virtual water flows under climate and population change scenarios: focusing on its determinants

Abstract Water resources are under increasing pressure from population growth, socio-economic development, and climate change. The main user of freshwater is the agriculture sector, accounting for 70–80% of global water use. Consequently, increasing water productivity and reducing water use in this sector are vital for alleviating water scarcity. It has been alleged that domestic or international trade of water-consumed products from wet-provinces or countries to arid and semi-arid provinces or countries is one possible path to mitigate water shortage. In this regard, virtual water flows and their determinants in Iran are investigated in this paper. This study examines the main determinants of bilateral virtual water flows associated with international trade in agricultural goods among Iran and other countries using a gravity model of trade. The impacts of climate change and socio-economic change scenarios on the virtual water trade are simulated. The result of the gravity model indicated that bilateral virtual water trade flows are influenced by the classical determinants and all the mass-related variables (gross domestic product and population) are significant with expected signs. Finally, the result obtained from the simulation of climate and socio-economic change scenarios showed that under the pessimistic scenario of climate change and population growth rate of 0.98 and 0.44%, VW trade between Iran and other countries would increase by 41 and 66% in the periods of 2016–2045 and 2070–2099, respectively. As a consequence, identifying the appropriate countries for business interactions and adopting effective trade policies are very important and need attention soon.