E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "Insights on the Water–Energy–Food Nexus"

A special issue of Water (ISSN 2073-4441). This special issue belongs to the section "Water–Food–Energy Nexus".

Deadline for manuscript submissions: closed (31 July 2019).

Special Issue Editors

Guest Editor
Prof. Dr. Vasilis Kanakoudis

Head of the Civil Engineering Department, Civil Engineering Department, University of Thessaly, Greece
Website | E-Mail
Interests: drinking water netwroks management; simulation and optimization; water quality; water and energy; water cost; water pricing; water resources management
Guest Editor
Dr. Stavroula Tsitsifli

Civil Engineering Department, University of Thessaly, Greece
Website | E-Mail
Interests: drinking water networks management; water networks performance evaluation; water quality; non-revenue water management; water pricing; environmental impact assessment

Special Issue Information

Dear Colleagues,

The Water–Energy–Food (WEF) Nexus concept sheds light on important interactions between these systems, and on the fact that their integrated management is key to achieving the Sustainable Development Goals. Under the pressures of population growth and urbanization, economic development, international trade and climate change, projections indicate that the demand for fresh water, energy and food will increase significantly over the coming decades. The WEF Nexus has been established as a useful way to integrate the complex and interrelated nature of our global resource systems. The WEF Nexus is an approach that allows to better understand and analyze the interlinkages between the natural environment and socio-economic activities, and to work towards a more coordinated management and use of natural resources across sectors and scales. Identifying and managing trade-offs and building synergies through this analysis allows for more integrated and sustainable planning, decision-making, policy-making and implementation. In this context, this Special Issue aims at providing insights on the WEF Nexus, presenting international case studies to bring together theory and practice. Authors are invited to submit their papers to this Special Issue.

Additionally, selected papers from the Third Efficient Water Systems (EWaS) International Conference, entitled “Insights on the Water–Energy–Food Nexus” will be published in this Special Issue.

Prof. Dr. Vasilis Kanakoudis
Dr. Stavroula Tsitsifli
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Water is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • water
  • energy
  • food
  • water-energy-food (WEF) nexus
  • water supply
  • water treatment

Published Papers (22 papers)

View options order results:
result details:
Displaying articles 1-22
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle
A Perception Study of an Integrated Water System Project in a Water Scarce Community in the Philippines
Water 2019, 11(8), 1593; https://doi.org/10.3390/w11081593
Received: 3 July 2019 / Revised: 27 July 2019 / Accepted: 30 July 2019 / Published: 31 July 2019
PDF Full-text (2344 KB) | HTML Full-text | XML Full-text
Abstract
The Integrated Water System (IWS) offers alternative water and sanitation services that can potentially benefit rural communities experiencing water scarcity. The IWS described in this study comprises three systems: The Rainwater Harvesting System (RWHS), Water Treatment System (WTS), and Eco-Toilet System (ETS). RWHS [...] Read more.
The Integrated Water System (IWS) offers alternative water and sanitation services that can potentially benefit rural communities experiencing water scarcity. The IWS described in this study comprises three systems: The Rainwater Harvesting System (RWHS), Water Treatment System (WTS), and Eco-Toilet System (ETS). RWHS and WTS make use of rainwater, which can be utilized for several domestic uses, especially during wet season. ETS has several benefits to users including promotion of environmental and public health, as well as food security. Despite the potential benefits of the IWS components, the perceived acceptance of its users threatens the success of its implementation. This study focuses on determining the significant factors that can influence the social acceptance of IWS in the Municipality of Mulanay, Quezon Province, Philippines. This study considers behavioral intention as an indicator of social acceptance of the IWS components. The framework of this study is based on the combined technology acceptance model and theory of planned behavior (C-TAM-TPB) concept. C-TAM-TPB was analyzed using Partial Least Square–Structural Equation Modeling (PLS–SEM). The result of the C-TAM-TPB evaluation reveals that the user’s attitude towards use (ATU), including its significant predictors, can promote behavioral intention towards use of the IWS components. This study can further improve the development of IWS projects. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Rice Cultivation without Synthetic Fertilizers and Performance of Microbial Fuel Cells (MFCs) under Continuous Irrigation with Treated Wastewater
Water 2019, 11(7), 1516; https://doi.org/10.3390/w11071516
Received: 14 June 2019 / Revised: 8 July 2019 / Accepted: 9 July 2019 / Published: 22 July 2019
PDF Full-text (1665 KB) | HTML Full-text | XML Full-text
Abstract
To obtain a high rice yield and quality for animal feed without synthetic fertilizers, an experiment with bench-scale apparatus was conducted by applying continuous irrigation with treated municipal wastewater (TWW). Uniform rice seedlings of a high-yield variety (Oryza sativa L., cv. Bekoaoba) [...] Read more.
To obtain a high rice yield and quality for animal feed without synthetic fertilizers, an experiment with bench-scale apparatus was conducted by applying continuous irrigation with treated municipal wastewater (TWW). Uniform rice seedlings of a high-yield variety (Oryza sativa L., cv. Bekoaoba) were transplanted in five treatments to examine different TWW irrigation directions (“bottom-to-top” and “top-to-top” irrigation) and fertilization practices (with and without P-synthetic fertilizers) as well as one control that simulated the irrigation and fertilization management of normal paddy fields. The highest rice yield (14.1 t ha−1), shoot dry mass (12.9 t ha−1), and protein content in brown rice (14.6%) were achieved using bottom-to-top irrigation, although synthetic fertilizers were not applied. In addition, this subsurface irrigation system could contribute to environmental protection by removing 85–90% of nitrogen from TWW more effectively than the top-to-top irrigation, which showed a removal efficiency of approximately 63%. No accumulation of heavy metals (Fe, Mn, Cu, Zn, Cd, Ni, Pb, Cr, and As) in the paddy soils was observed after TWW irrigation for five months, and the contents of these metals in the harvested brown rice were lower than the permissible limits recommended by international standards. A microbial fuel cell system (MFC) was installed in the cultivation system using graphite-felt electrodes to test the capacity of electricity generation; however, the electricity output was much lower than that reported in normal paddy fields. Bottom-to-top irrigation with TWW can be considered a potential practice to meet both water and nutrient demand for rice cultivation in order to achieve a very high yield and nutritional quality of cultivated rice without necessitating the application of synthetic fertilizers. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
MILP for Optimizing Water Allocation and Reservoir Location: A Case Study for the Machángara River Basin, Ecuador
Water 2019, 11(5), 1011; https://doi.org/10.3390/w11051011
Received: 16 April 2019 / Revised: 7 May 2019 / Accepted: 10 May 2019 / Published: 14 May 2019
PDF Full-text (7650 KB) | HTML Full-text | XML Full-text
Abstract
The allocation of water flowing through a river-with-reservoirs system to optimally meet spatially distributed and temporally variable demands can be conceived as a network flow optimization (NFO) problem and addressed by linear programming (LP). In this paper, we present an extension of the [...] Read more.
The allocation of water flowing through a river-with-reservoirs system to optimally meet spatially distributed and temporally variable demands can be conceived as a network flow optimization (NFO) problem and addressed by linear programming (LP). In this paper, we present an extension of the strategic NFO-LP model of our previous model to a mixed integer linear programming (MILP) model to simultaneously optimize the allocation of water and the location of one or more new reservoirs; the objective function to minimize only includes two components (floods and water demand), whereas the extended LP-model described in this paper, establishes boundaries for each node (reservoir and river segments) and can be considered closer to the reality. In the MILP model, each node is called a “candidate reservoir” and corresponds to a binary variable (zero or one) within the model with a predefined capacity. The applicability of the MILP model is illustrated for the Machángara river basin in the Ecuadorian Andes. The MILP shows that for this basin the water-energy-food nexus can be mitigated by adding one or more reservoirs. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Graphical abstract

Open AccessArticle
Avoiding Conflicts between Future Freshwater Algae Production and Water Scarcity in the United States at the Energy-Water Nexus
Water 2019, 11(4), 836; https://doi.org/10.3390/w11040836
Received: 2 March 2019 / Revised: 8 April 2019 / Accepted: 12 April 2019 / Published: 20 April 2019
PDF Full-text (6266 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Sustainable production of algae will depend on understanding trade-offs at the energy-water nexus. Algal biofuels promise to improve the environmental sustainability profile of renewable energy along most dimensions. In this assessment of potential US freshwater production, we assumed sustainable production along the carbon [...] Read more.
Sustainable production of algae will depend on understanding trade-offs at the energy-water nexus. Algal biofuels promise to improve the environmental sustainability profile of renewable energy along most dimensions. In this assessment of potential US freshwater production, we assumed sustainable production along the carbon dimension by simulating placement of open ponds away from high-carbon-stock lands (forest, grassland, and wetland) and near sources of waste CO 2 . Along the water dimension, we quantified trade-offs between water scarcity and production for an ‘upstream’ indicator (measuring minimum water supply) and a ‘downstream’ indicator (measuring impacts on rivers). For the upstream indicator, we developed a visualization tool to evaluate algae production for different thresholds for water surplus. We hypothesized that maintaining a minimum seasonal water surplus would also protect river habitat for aquatic biota. Our study confirmed that ensuring surplus water also reduced the duration of low-flow events, but only above a threshold. We also observed a trade-off between algal production and the duration of low-flow events in streams. These results can help to guide the choice of basin-specific sustainability targets to avoid conflicts with competing water users at this energy-water nexus. Where conflicts emerge, alternative water sources or enclosed photobioreactors may be needed for algae cultivation. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Different Approaches to Estimation of Drainage Density and Their Effect on the Erosion Potential Method
Water 2019, 11(3), 593; https://doi.org/10.3390/w11030593
Received: 28 January 2019 / Revised: 15 March 2019 / Accepted: 18 March 2019 / Published: 21 March 2019
PDF Full-text (21075 KB) | HTML Full-text | XML Full-text
Abstract
This paper analyses the possibilities of improving the precision of, and obtaining better, drainage density (Dd) input data for the Erosion Potential Method (EPM). This method is used for erosion assessments in karst areas that are characterised by torrential watercourses. The analysis is [...] Read more.
This paper analyses the possibilities of improving the precision of, and obtaining better, drainage density (Dd) input data for the Erosion Potential Method (EPM). This method is used for erosion assessments in karst areas that are characterised by torrential watercourses. The analysis is conducted in the Dubračina catchment in Croatia. Four different methodologies are used to derive a Dd map. The approaches use different assumptions and allow different spatial variability. The first two are commonly applied in the EPM. The Dd in the first case scenario corresponds to very low Dd and is homogenous throughout the entire catchment. In the second case, Dd is calculated on the sub-catchment level and varies from very low to medium. The third and fourth case scenarios provide the most spatially variant maps. The output of the third case is the actual Dd based on a topographic map, and the fourth potential Dd is based on a river network map derived from a Lidar digital elevation model. The third and fourth case scenarios provide better spatial variability for the Dd parameter, and both case scenarios are considered appropriate input data for the EPM and an improvement of the accuracy and precision of the EPM. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Slip Factor Correction in 1-D Performance Prediction Model for PaTs
Water 2019, 11(3), 565; https://doi.org/10.3390/w11030565
Received: 29 December 2018 / Revised: 12 March 2019 / Accepted: 13 March 2019 / Published: 19 March 2019
PDF Full-text (12331 KB) | HTML Full-text | XML Full-text
Abstract
In recent years, pumps operated as turbines (PaTs) have been gaining the interest of industry and academia. For instance, PaTs can be effectively used in micro hydropower plants (MHP) and water distribution systems (WDS). Therefore, further efforts are necessary to investigate their fluid [...] Read more.
In recent years, pumps operated as turbines (PaTs) have been gaining the interest of industry and academia. For instance, PaTs can be effectively used in micro hydropower plants (MHP) and water distribution systems (WDS). Therefore, further efforts are necessary to investigate their fluid dynamic behavior. Compared to conventional turbines, a lower number of blades is employed in PaTs, lowering their capability to correctly guide the flow, hence reducing the Euler’s work; thus, the slip phenomenon cannot be neglected at the outlet section of the runner. In the first part of the paper, the slip phenomenon is numerically investigated on a simplified geometry, evidencing the dependency of the lack in guiding the flow on the number of blades. Then, a commercial double suction centrifugal pump, characterized by the same specific speed, is considered, evaluating the dependency of the slip on the flow rate. In the last part, a slip factor correlation is introduced based on those CFD simulations. It is shown how the inclusion of this parameter in a 1-D performance prediction model allows us to reduce the performance prediction errors with respect to experiments on a pump with a similar specific speed by 5.5% at design point, compared to no slip model, and by 8% at part-loads, rather than using Busemann and Stodola formulas. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Ultrasound-Assisted Treatment of Landfill Leachate in a Sequencing Batch Reactor
Water 2019, 11(3), 516; https://doi.org/10.3390/w11030516
Received: 8 January 2019 / Revised: 5 March 2019 / Accepted: 7 March 2019 / Published: 12 March 2019
PDF Full-text (3947 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Purification of leachates is currently a big challenge due to their high variability in composition and amount. The complexity of the medium, namely leachates, makes new solutions highly sought after and finds the existing ones in need of optimization. The effects of ultrasound [...] Read more.
Purification of leachates is currently a big challenge due to their high variability in composition and amount. The complexity of the medium, namely leachates, makes new solutions highly sought after and finds the existing ones in need of optimization. The effects of ultrasound pretreatment (20 kHz, 12 µm) on biological treatment of landfill leachates in the form of processes carried out in two sequencing batch reactors were investigated. The experiment was divided into two stages. In the first stage, leachate was treated by an ultrasonic field at different sonication times (0.5, 1, 3, 5, 10 and 15 min). Next, leachates with and without conditioning were combined with municipal wastewater in the following ratios: 5, 10, 15 and 25% v/v. For optimal processing time (3 min), 16% removal of COD was achieved. In turn, the BOD5/COD ratio was 0.3, which is higher by approximately 270% than that of the non-conditioned sample. Further elongation of sonication time did not significantly affect both parameters. Also, pretreatment of leachate resulted in a maximum increase noted in the study of specific oxygen uptake rate and dehydrogenase activity of approximately 21 and 2 times compared to the non-conditioned sample. The implementation of a pretreatment step prior to the biological treatment was shown to result in higher pollutant removal efficiency. Depending on the share of leachates in the mixture, the removal enhancements of BOD, COD, and ammonium nitrogen for conditioned samples ranged from 6–48.5%, 4–48% and 11–42%, respectively. Furthermore, pretreatment of leachate allows for an increased (by up to 20%) share of leachate volume in the influent stream entering the reactor, while maintaining the quality of effluents in accordance with national regulation requirements. However, in scenarios without pretreatment, the leachate ratio cannot exceed 5% of the total wastewater due to poor quality of the effluents. The operational cost of ultrasound pretreatment of leachate was 22.58 €/(m3·g removed COD). Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
The Application of Multi-Criteria Analysis Methods for the Determination of Priorities in the Implementation of Irrigation Plans
Water 2019, 11(3), 501; https://doi.org/10.3390/w11030501
Received: 27 December 2018 / Revised: 8 February 2019 / Accepted: 5 March 2019 / Published: 10 March 2019
PDF Full-text (3328 KB) | HTML Full-text | XML Full-text
Abstract
Irrigated agriculture has considerable impacts on the environment. To minimize negative effects and maximize positive effects, it is necessary to provide comprehensive analyses beyond the strictly technical domain. In this study, we apply a methodology for determining priorities in implementing irrigation plans using [...] Read more.
Irrigated agriculture has considerable impacts on the environment. To minimize negative effects and maximize positive effects, it is necessary to provide comprehensive analyses beyond the strictly technical domain. In this study, we apply a methodology for determining priorities in implementing irrigation plans using multi-criteria analysis methods on a specific case study area in the sub-catchment area of the Orljava River in Požega–Slavonia County, Croatia. Five potential irrigation areas (Orljava–Londža, Pleternica, Ovčare, Treštanovci, and Venje–Hrnjevac) were analyzed according to five selected criteria: environmental protection, water-related (four sub-criteria), social, economic, and time criteria with different criteria importance (weight). The aim of this study was to confirm the adequacy of using six multi-criteria analysis (MCA) methods (mostly used: PROMETHEE, AHP, ELECTRE TRI, and the less used: DEXi, PRIME, and PCA) in determining priorities for fulfilling irrigation plans, present models for preparation of the input data, apply certain methods, and compare the results on the selected case study area. The methods’ adequacy was confirmed during the research. Five of the six MCA methods identified the Ovčare area as the most appropriate for irrigation development (i.e., it has priority in implementing the irrigation plan). According to one (AHP) of the six methods, Orljava–Londža has more advantages over other areas. All MCA methods, except PCA, chose Venje–Hrnjevac as the least advisable (last to be implemented) alternative. Conclusions from this research confirm findings from recently published research regarding the application of MCA on water management problems. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Sustainability Analysis of Alternative Long-Term Management Strategies for Water Supply Systems: A Case Study in Reggio Emilia (Italy)
Water 2019, 11(3), 450; https://doi.org/10.3390/w11030450
Received: 21 December 2018 / Revised: 15 February 2019 / Accepted: 26 February 2019 / Published: 3 March 2019
PDF Full-text (8676 KB) | HTML Full-text | XML Full-text
Abstract
Increasing urban water demand and water stress conditions due to population growth, combined with climate change and a non-uniform distribution of water resources in space and time, represent major concerns for water companies. As such, long-term management strategies need to improve the resilience [...] Read more.
Increasing urban water demand and water stress conditions due to population growth, combined with climate change and a non-uniform distribution of water resources in space and time, represent major concerns for water companies. As such, long-term management strategies need to improve the resilience of water supply systems and account for the sustainability of water withdrawals. In this context, metabolic modelling may provide a support to decision-making in the medium-long term, based on sustainability criteria. This approach enables mimicking a water supply network (WSN) based on a set of material and energy fluxes that interact and influence each other. By analyzing these fluxes, a suite of key performance indicators (KPIs) is evaluated in order to identify which kind of interventions may be applied to increase the sustainability of the system. Here, we apply a metabolic model, WaterMet2, to a WSN in the Reggio Emilia Province (Italy), combined with hydraulic simulations conducted with EPANET. Different alternative strategies are compared, including a reduction of water withdrawals from the main well field due to a possible future decrease in water availability. Based on KPIs, sustainable long-term strategies are evaluated in order to identify the most suitable solution for dynamic sustainable management of the water supply system. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Graphical abstract

Open AccessArticle
Synergistic Approach of Remote Sensing and GIS Techniques for Flash-Flood Monitoring and Damage Assessment in Thessaly Plain Area, Greece
Water 2019, 11(3), 448; https://doi.org/10.3390/w11030448
Received: 18 December 2018 / Revised: 16 February 2019 / Accepted: 26 February 2019 / Published: 3 March 2019
PDF Full-text (23861 KB) | HTML Full-text | XML Full-text
Abstract
This paper describes the synergetic use of earth observation satellites optical and radar data with a high-resolution digital elevation model (DEM) to detect flooded areas and explore the impacts of a flood event. A flash flood episode took place in May 2016, in [...] Read more.
This paper describes the synergetic use of earth observation satellites optical and radar data with a high-resolution digital elevation model (DEM) to detect flooded areas and explore the impacts of a flood event. A flash flood episode took place in May 2016, in the central-eastern part of West Thessaly (Central Greece). Landsat-7 ETM+ and a Sentinel-1 SAR images were acquired. For Landsat-7, several water indices were applied and for the Sentinel-1 a threshold method was implemented. Elevation data were also used to improve the delineation of the inundated areas, and to estimate flood water depth. Furthermore, Sentinel-2 images were utilized so as to record the land use/cover of the flooded area. The inundated areas and the affected cultivations were delineated with high precision, and the financial effects were evaluated. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Green Smart Technology for Water (GST4Water): Water Loss Identification at User Level by Using Smart Metering Systems
Water 2019, 11(3), 405; https://doi.org/10.3390/w11030405
Received: 28 December 2018 / Revised: 18 February 2019 / Accepted: 20 February 2019 / Published: 26 February 2019
Cited by 1 | PDF Full-text (13194 KB) | HTML Full-text | XML Full-text
Abstract
A real-time household water consumption monitoring and processing system aimed at leakage identification at user level is presented here. The system, developed within the GST4Water project, allows consumption data sent by a generic smart meter installed in a user’s house to be received [...] Read more.
A real-time household water consumption monitoring and processing system aimed at leakage identification at user level is presented here. The system, developed within the GST4Water project, allows consumption data sent by a generic smart meter installed in a user’s house to be received and transferred to a cloud platform. Here, the consumption data are stored and processed through an empirical algorithm able to automatically identify leakage at the individual user level by looking for non-consumption in certain periods of the day. With reference to a real-life case study, the results obtained show that the algorithm enables leakages on users’ properties to be identified with an accuracy of more than 90%. Therefore, the implementation of this algorithm within a highly innovative smart metering system can represent an efficient tool for reducing water losses at user level. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Green Smart Technology for Water (GST4Water): Life Cycle Analysis of Urban Water Consumption
Water 2019, 11(2), 389; https://doi.org/10.3390/w11020389
Received: 30 December 2018 / Revised: 11 February 2019 / Accepted: 16 February 2019 / Published: 23 February 2019
PDF Full-text (1853 KB) | HTML Full-text | XML Full-text
Abstract
The increasing scarcity of water is encouraging strategies in water saving and urban water management systems devoted to reducing natural resource consumption and environmental impact. At household and urban scales, there is an increasing interest in onsite greywater and non-potable water reuse systems [...] Read more.
The increasing scarcity of water is encouraging strategies in water saving and urban water management systems devoted to reducing natural resource consumption and environmental impact. At household and urban scales, there is an increasing interest in onsite greywater and non-potable water reuse systems in order to improve water availability. In this framework, the project GST4Water funded by the European Union (EU) under the POR-FESR 2014–2020 Program of Emilia-Romagna Region, has been developed with the aim to implement water consumption monitoring systems, to define solutions for greywater reuse, and to develop tools for environmental sustainability evaluation applied to water systems. The present study focuses on this last goal, performing a life cycle assessment of the solutions optimized at a district level. In particular, six different scenarios are compared, starting from two models considering traditional water supply together with or without energy consumption related to hot water generation, and five additional models related with different assumptions in terms of greywater recovery systems, and energy and hot water production, at varying percentages of renewable and photovoltaic energy supply. Finally, an evaluation of the return time of environmental investment is carried out, based on the results obtained through the scenario analysis. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Towards Ranking the Water–Energy–Food–Land Use–Climate Nexus Interlinkages for Building a Nexus Conceptual Model with a Heuristic Algorithm
Water 2019, 11(2), 306; https://doi.org/10.3390/w11020306
Received: 28 December 2018 / Revised: 7 February 2019 / Accepted: 10 February 2019 / Published: 12 February 2019
PDF Full-text (5174 KB) | HTML Full-text | XML Full-text
Abstract
The concept of the Water–Energy–Food nexus (WEF), as documented by the United Nations Food and Agriculture Organization (FAO), suggests that the three resources are thoroughly interrelated, shaping a complicated web of interlinkages. Perceiving the three commodities as an interdependent variable system, rather than [...] Read more.
The concept of the Water–Energy–Food nexus (WEF), as documented by the United Nations Food and Agriculture Organization (FAO), suggests that the three resources are thoroughly interrelated, shaping a complicated web of interlinkages. Perceiving the three commodities as an interdependent variable system, rather than isolated subsystems is a step towards a more holistic approach, and thus a prerequisite to introducing a sustainable scheme for better managing resources. In this work, the well-documented WEF nexus is broadened to a five-dimensional nexus, also involving land use and climate. A methodology for drawing the interrelations among the five dimensions and unreeling the complicated system of direct and indirect interlinkages is given. The intensity of interlinkages among nexus components is initially assessed through a three-point typology with interlinkage scoring corresponding to resource use in Greece. The typology is used and is further expanded to quantify successfully all interlinkages among nexus components with a proposed heuristic algorithm. Results are used to create the cross-interlinkage matrix that identifies food as the most influencing resource and water as the resource mostly influenced by other nexus elements. Results show that indirect interlinkages of multiple resources can be very significant and should not be ignored when planning nexus-coherent policy initiatives and investments in different sectors, in order to promote resource efficiency. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Deciphering Interannual Temperature Variations in Springs of the Campania Region (Italy)
Water 2019, 11(2), 288; https://doi.org/10.3390/w11020288
Received: 24 December 2018 / Revised: 31 January 2019 / Accepted: 3 February 2019 / Published: 7 February 2019
Cited by 1 | PDF Full-text (4572 KB) | HTML Full-text | XML Full-text
Abstract
While the effects of climate change on the thermal regimes of surface waters have already been assessed by many studies, there is still a lack of knowledge on the effects on groundwater temperature and on the effects on spring water quality. The online [...] Read more.
While the effects of climate change on the thermal regimes of surface waters have already been assessed by many studies, there is still a lack of knowledge on the effects on groundwater temperature and on the effects on spring water quality. The online available dataset of the Campania Environmental Agency (ARPAC) was analysed via spatial, temporal and statistical analyses to assess the impact of climate variability on 118 springs, monitored over the period from 2002 to 2017. The meteorological dataset was used to compute average annual precipitation and atmospheric temperatures. Spring water temperatures, electrical conductivity, pH, chloride and fluoride were selected to determine if climate variations had a significant impact on spring water quality. This study shows that the Campania region has experienced an increase of spring water temperatures of approximately 2.0 °C during the monitored period. This is well-linked with the increase of atmospheric minimum temperatures, but not with average and maximum atmospheric temperatures. The spring water temperature increases were not reflected by a concomitant change of the analysed water quality parameters. The latter were linked to the precipitation trend and other local factors, like spring altitude and the presence of geothermal heat fluxes. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessFeature PaperArticle
Optimizing the Formation of DMAs in a Water Distribution Network through Advanced Modelling
Water 2019, 11(2), 278; https://doi.org/10.3390/w11020278
Received: 25 October 2018 / Revised: 18 December 2018 / Accepted: 31 January 2019 / Published: 6 February 2019
PDF Full-text (3200 KB) | HTML Full-text | XML Full-text
Abstract
Water pressure management in a water distribution network (WDN) is a key component applied to achieve desirable water quality as well as a trouble-free operation of the network. This paper presents a hybrid, two-stage approach, to provide optimal separation of a WDN into [...] Read more.
Water pressure management in a water distribution network (WDN) is a key component applied to achieve desirable water quality as well as a trouble-free operation of the network. This paper presents a hybrid, two-stage approach, to provide optimal separation of a WDN into District Metered Areas (DMAs), improving both water age and pressure. The first stage aims to divide the WDN into smaller areas via the Geometric Partitioning method, which is based on Recursive Coordinate Bisection (RCB). Subsequently, the Student’s t-mixture model (SMM) is applied to each area, providing an optimal placement of isolation valves and separating the network in DMAs. The model is evaluated on a realistic network generated through Watergems and is compared against one variation of it implemented, including the Gaussian Mixture Model (GMM) as well as the Genetic Algorithm (GA) approach, obtaining impressive performance. The implementation of both stages was deployed in a MATLAB environment through the Epanet toolkit. The proposed system is very promising, especially for large size WDNs due to the decreased running time and noteworthy reduction of pressure and water age. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Strategies for the Controlled Integration of Food SMEs’ Highly Polluted Effluents into Urban Sanitation Systems
Water 2019, 11(2), 223; https://doi.org/10.3390/w11020223
Received: 28 December 2018 / Revised: 21 January 2019 / Accepted: 22 January 2019 / Published: 29 January 2019
PDF Full-text (3610 KB) | HTML Full-text | XML Full-text
Abstract
The artisan production of canned tuna is characterized by generating effluents with high organic and saline loads, which complicates their suitable treatment. The main objective of the LIFE VERTALIM project is to demonstrate the efficiency of a holistic solution (including technical, legislative, social, [...] Read more.
The artisan production of canned tuna is characterized by generating effluents with high organic and saline loads, which complicates their suitable treatment. The main objective of the LIFE VERTALIM project is to demonstrate the efficiency of a holistic solution (including technical, legislative, social, and environmental aspects) for the controlled integration of food industry wastewater from small and medium enterprises (SMEs) in the urban sanitation system with the compliance of all stakeholders. This work shows the viability of the implementation of low-cost innovative solutions, through the clean and eco-efficient production and wastewater pretreatment for fish canneries. This solution allows on average a reduction of 30% of the wastewater discharges to the environment and a reduction of food losses of up to 0.1%. Moreover, there is a reduction of between 40% and 90% related to high organic load. These results allow the canneries to dispose their pretreated effluents to the urban sanitation system, avoiding the high costs of an industrial wastewater treatment plant (WWTP) to discharge to the river. A better physical-chemical quality in the river waters as a well as the marine water surrounding the urban WWTP have been achieved. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Fuzzy Solution to the Unconfined Aquifer Problem
Water 2019, 11(1), 54; https://doi.org/10.3390/w11010054
Received: 15 November 2018 / Revised: 19 December 2018 / Accepted: 21 December 2018 / Published: 29 December 2018
PDF Full-text (5552 KB) | HTML Full-text | XML Full-text
Abstract
In this article, the solution to the fuzzy second order unsteady partial differential equation (Boussinesq equation) is examined, for the case of an aquifer recharging from a lake. In the examined problem, there is a sudden rise and subsequent stabilization of the lake’s [...] Read more.
In this article, the solution to the fuzzy second order unsteady partial differential equation (Boussinesq equation) is examined, for the case of an aquifer recharging from a lake. In the examined problem, there is a sudden rise and subsequent stabilization of the lake’s water level, thus the aquifer is recharging from the lake. The aquifer boundary conditions are fuzzy and create ambiguities to the solution of the problem. Since the aforementioned problem concerns differential equations, the generalized Hukuhara (gH) derivative was used for total derivatives, as well as the extension of this theory concerning partial derivatives. The case studies proved to follow the generalized Hukuhara (gH) derivative conditions and they offer a unique solution. The development of the aquifer water profile was examined, as well as the calculation of the recharging fuzzy water movement profiles, velocity, and volume, and the results were depicted in diagrams. According to presented results, the hydraulic engineer, being specialist in irrigation projects or in water management, could estimate the appropriate water volume quantity with an uncertainty level, given by the α-cuts. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
At-Site Assessment of a Regional Design Criterium for Water-Demand Peak Factor Evaluation
Water 2019, 11(1), 24; https://doi.org/10.3390/w11010024
Received: 12 November 2018 / Revised: 15 December 2018 / Accepted: 18 December 2018 / Published: 24 December 2018
PDF Full-text (3376 KB) | HTML Full-text | XML Full-text
Abstract
In this study an analysis of the water supply variability for three towns in Puglia (Southern Italy), Roccaforzata, Palagianello and Palagiano, was carried out, based on time series continuously recorded over two years. The towns’ population ranges between 1800 and 16,000 inhabitants and [...] Read more.
In this study an analysis of the water supply variability for three towns in Puglia (Southern Italy), Roccaforzata, Palagianello and Palagiano, was carried out, based on time series continuously recorded over two years. The towns’ population ranges between 1800 and 16,000 inhabitants and the flow data, collected with time steps of 10 min, are referred to drinking water in an urban environment. The frequency analysis was conducted on the hourly and instantaneous peak factors and confirmed that the Gumbel distribution is able to represent the stochastic behavior of the peak water demand. A physically based formulation of the distribution parameters was exploited in order to investigate the regional distribution of the peak factor for towns with a different population. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Addressing Gaps in Environmental Water Policy Issues across Five Mediterranean Freshwater Protected Areas
Water 2018, 10(12), 1853; https://doi.org/10.3390/w10121853
Received: 12 November 2018 / Revised: 11 December 2018 / Accepted: 12 December 2018 / Published: 14 December 2018
PDF Full-text (2537 KB) | HTML Full-text | XML Full-text
Abstract
The increasing pressure on water resources in Europe’s broader area led member states to take measures and adopt a common legislative “umbrella” of directives to protect them. The aim of this research is to investigate practicing deficiencies, information lacks and distances from optimal [...] Read more.
The increasing pressure on water resources in Europe’s broader area led member states to take measures and adopt a common legislative “umbrella” of directives to protect them. The aim of this research is to investigate practicing deficiencies, information lacks and distances from optimal status as set by the Water Framework Directive and supporting water uses. This contributes to the improvement of the efficiency and harmonization of all environmental goals especially when management of Protected Areas is addressed. Gap analysis, an approach that reveals the distance between current and desired level, was carried out, targeting five Mediterranean hydro-ecosystems, covering three major water policy pillars “Monitoring Practices”, “Management Practices” and “Water Quality and Pressures”. Data for such analyses was collected by literature research supported by a query matrix. The findings revealed a lack in compliance with the Water Framework Directive regarding the “Monitoring Practices” and several deficiencies in sites burdened by eutrophication and human pressures on “Water Quality and Pressures” field. As for “Management Practices”, extra effort should be applied in all hydro-ecosystems to reach the desirable state. We suggest that gap analysis, as a harmonization tool, can unify apparently different areas under the same goals to reveal the extra necessary “investment”. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Graphical abstract

Open AccessArticle
A Note on One- and Three-Dimensional Infiltration Analysis from a Mini Disc Infiltrometer
Water 2018, 10(12), 1783; https://doi.org/10.3390/w10121783
Received: 24 October 2018 / Revised: 22 November 2018 / Accepted: 29 November 2018 / Published: 4 December 2018
PDF Full-text (2460 KB) | HTML Full-text | XML Full-text
Abstract
Disc infiltrometers are used to characterize soil hydraulic properties. The purpose of this study was to determine the difference between three- and one-dimensional infiltration and to calculate the infiltration shape parameter γ from a proposed analytical infiltration equation. One- and three-dimensional infiltration tests [...] Read more.
Disc infiltrometers are used to characterize soil hydraulic properties. The purpose of this study was to determine the difference between three- and one-dimensional infiltration and to calculate the infiltration shape parameter γ from a proposed analytical infiltration equation. One- and three-dimensional infiltration tests were done on three repacked soils (loam, sandy loam, and silty clay loam) for two negative pressure heads. A mini disc infiltrometer of a radius of 22.5 mm with suction that ranged from −5 mm to −70 mm was used. The difference between experimental three- and one-dimensional cumulative infiltration was linear with time, which confirmed the proposed equation. In this study, the shape parameter γ seems not to be seriously affected by the soil type and acquires values from 0.561 to 0.615, i.e., smaller than the value γ = 0.75, which is widely used. With these values, the criteria proposed for calculating hydraulic conductivity using three-dimensional infiltration data may be fulfilled in most soils. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Open AccessArticle
Soil Salinity Assessment Using Saturated Paste and Mass Soil:Water 1:1 and 1:5 Ratios Extracts
Water 2018, 10(11), 1589; https://doi.org/10.3390/w10111589
Received: 17 October 2018 / Revised: 2 November 2018 / Accepted: 2 November 2018 / Published: 6 November 2018
Cited by 1 | PDF Full-text (1286 KB) | HTML Full-text | XML Full-text
Abstract
Soil salinization is directly related to the quantity and quality of food production, and often, to increased energy demands for high-quality irrigation water. Reliable monitoring of soil salinity based on a less laborious method than the soil saturated paste (SP) extract methodology is [...] Read more.
Soil salinization is directly related to the quantity and quality of food production, and often, to increased energy demands for high-quality irrigation water. Reliable monitoring of soil salinity based on a less laborious method than the soil saturated paste (SP) extract methodology is required. In the present study, an attempt is made to relate the electrical conductivity (EC) of the soil saturated paste (SP) extract (ECe) with the EC determined in the 1:1 and 1:5 soil over water mass ratios, (soil:water) extracts (EC1:1 and EC1:5). ECe, EC1:1, and EC1:5 values were obtained for 198 soil samples from five different locations in Greece. The results have shown that strong linear relationships exist between the ECe and the EC1:1 and EC1:5 values (R2 > 0.93), and that the slopes of these linear relationships decreased from coarse to fine soil types. For 123 soil samples, the concentrations of Κ+, Νa+, Ca2+, Mg2+, and Cl were also determined in the extracts of the three applied methodologies. Ion concentrations in the 1:1 and 1:5 extracts were highly correlated with the respective ion concentrations in the SP extracts. These findings strongly suggest that EC1:1 and EC1:5 values can be safely used for the estimation of ECe. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Review

Jump to: Research

Open AccessReview
A Review of the 21st Century Challenges in the Food-Energy-Water Security in the Middle East
Water 2019, 11(4), 682; https://doi.org/10.3390/w11040682
Received: 11 February 2019 / Revised: 23 March 2019 / Accepted: 29 March 2019 / Published: 2 April 2019
Cited by 1 | PDF Full-text (6108 KB) | HTML Full-text | XML Full-text
Abstract
Developing countries have experienced significant challenges in meeting their needs for food, energy, and water security. This paper presents a country-level review of the current issues associated with Food-Energy-Water (FEW) security in the Middle East. In this study, sixteen countries in the Middle [...] Read more.
Developing countries have experienced significant challenges in meeting their needs for food, energy, and water security. This paper presents a country-level review of the current issues associated with Food-Energy-Water (FEW) security in the Middle East. In this study, sixteen countries in the Middle East are studied, namely Iraq, Iran, Syria, Lebanon, Israel, Palestine, Egypt, Turkey, and the Arabian Peninsula (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia (KSA), United Arab Emirates (UAE), and Yemen). Here, we conduct a comprehensive assessment to study and evaluate the emerging drivers of FEW systems in the region. The investigated drivers include water security, extreme events, economic growth, urbanization, population growth, poverty, and political stability. The results suggest that most of the studied countries are facing FEW resource insecurity or weak planning/management strategies. Our evaluation further revealed the current status of each country with respect to each factor, and suggested that climatic and socioeconomic factors have contributed to the subsequent stress on FEW resources, specifically on the water sector. In general, and with respect to the water-energy security, it was found that energy production in the Middle East is highly constrained by water deficiency, drought, and/or economic growth. The water-food security in the region is mainly affected by drought, water scarcity, population growth, urbanization, and/or political unrest. Full article
(This article belongs to the Special Issue Insights on the Water–Energy–Food Nexus)
Figures

Figure 1

Water EISSN 2073-4441 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top