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Water for Food and Energy Security | An Assessment of the Impacts of Water Scarcity on Agricultural Production and Electricity Generation in the Middle East and North Africa Texte intégral
2018
Miralles-Wilhelm, Fernando | Hejazi, Mohamad | Kim, Song | Yonkofski, Catherine | Watson, David | Kyle, Page | Liu, Yaling | Vernon, Chris | Delgado, Alison | Edmonds, Jae | Clarke, Leon
Water, energy, and agriculture have been conventionally dealt with separately in investment planning. For each of these sectors, regulatory frameworks, organizations, and infrastructures have been put in place to address sector-specific challenges and demands. As the Middle East and North Africa works towards building a more sustainable future, a nexus approach that considers the risks and synergies among these sectors is needed. To demonstrate the added value of a nexus approach, this report applies scenario analysis and integrated assessment modelling of the water-energy-food nexus to the Middle East and North Africa. The analysis finds that water scarcity increases in all countries in the region over the coming decades, mostly due to growing demands. More importantly, the analysis finds that many countries in the region could run out of fossil groundwater by 2050 unless measures to curb unsustainable abstraction are implemented. The impacts of growing scarcity on agriculture are significant, with production projected to drop by 60 percent by 2050 in some countries. On the upside, reducing the dependence of the agricultural and energy sectors on water and transitioning to renewable energies can reduce water scarcity, at the same time reducing greenhouse gas emissions.
Afficher plus [+] Moins [-]Water for Food and Energy Security : An Assessment of the Impacts of Water Scarcity on Agricultural Production and Electricity Generation in the Middle East and North Africa Texte intégral
2018
Miralles-Wilhelm, Fernando | Hejazi, Mohamad | Kim, Song | Yonkofski, Catherine | Watson, David | Kyle, Page | Liu, Yaling | Vernon, Chris | Delgado, Alison | Edmonds, Jae | Clarke, Leon
Water, energy, and agriculture have been conventionally dealt with separately in investment planning. For each of these sectors, regulatory frameworks, organizations, and infrastructures have been put in place to address sector-specific challenges and demands. As the Middle East and North Africa works towards building a more sustainable future, a nexus approach that considers the risks and synergies among these sectors is needed. To demonstrate the added value of a nexus approach, this report applies scenario analysis and integrated assessment modelling of the water-energy-food nexus to the Middle East and North Africa. The analysis finds that water scarcity increases in all countries in the region over the coming decades, mostly due to growing demands. More importantly, the analysis finds that many countries in the region could run out of fossil groundwater by 2050 unless measures to curb unsustainable abstraction are implemented. The impacts of growing scarcity on agriculture are significant, with production projected to drop by 60 percent by 2050 in some countries. On the upside, reducing the dependence of the agricultural and energy sectors on water and transitioning to renewable energies can reduce water scarcity, at the same time reducing greenhouse gas emissions.
Afficher plus [+] Moins [-]Benthic-pelagic trophic coupling in an Arctic marine food web along vertical water mass and organic matter gradients Texte intégral
2018
Stasko, Ashley D | Bluhm, Bodil | Michel, Christine | Archambault, Philippe | Majewski, Andrew | Reist, James D | Swanson, Heidi | Power, Michael
Source at: <a href=http://doi.org/10.3354/meps12582> http://doi.org/10.3354/meps12582</a> | Understanding drivers of benthic-pelagic coupling in Arctic marine ecosystems is key to identifying benthic areas that may be sensitive to climate-driven changes in hydrography and surface production. We coupled algal biomass and sedimentary characteristics with stable isotope data for 113 fishes and invertebrates in the Canadian Beaufort Sea and Amundsen Gulf to examine how trophic structure was influenced by the vertical water mass structure and organic matter input regimes, from 20 to 1000 m depths. Indices of community-level trophic diversity (isotopic niche size, 13C enrichment relative to a pelagic baseline, and δ13C isotopic range) increased from west to east, coincident with the use of more diverse dietary carbon sources among benthic functional groups. Data suggested benthic-pelagic trophic coupling was strongest in the western study region where pelagic sinking flux is relatively high, intermediate in the central region dominated by riverine inputs of terrestrial organic matter, and weakest in the east where strong pelagic grazing is known to limit sinking flux. Differences in δ13C between pelagic and benthic functional groups (up to 5.7 ‰) increased from west to east, and from the nearshore shelf to the upper slope. On the upper slope, much of the sinking organic matter may be intercepted in the water column, and dynamic hydrography likely diversifies available food sources. In waters > 750 m, there were no clear trends in benthic-pelagic coupling or community-level trophic diversity. This study represents the first description of fish and invertebrate food web structure > 200 m in the Canadian Beaufort Sea.
Afficher plus [+] Moins [-]Deep eutectic solvent based advance microextraction method for determination of aluminum in water and food samples: Multivariate study Texte intégral
2018
Panhwar, Abdul Haleem | Tuzen, Mustafa | Kazi, Tasneem Gul
Preconcentration of aluminum Al³⁺ was carried out by a novel deep eutectic solvent based ultrasound-assisted liquid phase microextraction (DES-UALPME) method. The deep eutectic solvents (DESs), a green solvent was first time used for enrichment and quantification of very low concentration of Al³⁺ in water and food samples, prior to analysed by electrothermal atomic absorption spectrometry (ETAAS). In present method it was observed that % recovery of Al-8-hydroxyquinoline chelates efficiently extracted by DES solvent. Pre-enrichment factor and limit of detection were observed to be 50, and 0.032μgL⁻¹, respectively. Developed procedure was validated with the CRM (SLRS-5 river water) of Al and a good agreement was observed in results of measured value to the certified value. The RSD was calculated as 3.3%. The presented procedure was successfully carried out to different water and food samples.
Afficher plus [+] Moins [-]Institutional arrangements for beneficial regional cooperation on water, energy and food priority issues in the Eastern Nile Basin Texte intégral
2018
Al-Saidi, Mohammad | Hefny, Amr
Research on water cooperation in the Eastern Nile Basin has focused on expanding policy and diplomacy tools for a better allocation of transboundary water resources confined to the river. Regional cooperation on water and related sectors such as energy and land expands the bargaining and areas for mutual gain, and thus enhances cooperation perspectives. This paper looks at the contribution and the potential benefits of a regional cooperation approach to addressing the underlying challenges of water diplomacy, such as complexity and distrust. It also promotes the understanding of river basins as a “resource basin” of integrated and linked resource-use issues, not always related to the river flow. The paper provides an analysis of priority issues for water–energy–food nexus in regional cooperation in the Eastern Nile Basin. This basin represents an illustrative case for regional cooperation and increased integration due to multiple comparative advantages inherent in the uneven endowments of water, energy and arable land resources, and to varying levels of economic and technological advancement among the three riparian countries: Egypt, Sudan and Ethiopia. The paper also analyzes institutional arrangements on a regional scale, and elaborates on the inherent trade-offs associated with them.
Afficher plus [+] Moins [-]Contribution of Water Management and Flood Protection to Food Security and Sustainable Development of Coastal and Deltaic Areas Texte intégral
2018
Schultz, Bart
In the field of irrigation, drainage and flood protection are two items crucial for the world's population, as well as for the work of the International Commission on Irrigation and Drainage (ICID) as a global association of professionals in the water sector. The first concerns the contribution of water management to food security and the second the impacts of man‐induced changes in land use and climate change on living and working in coastal and deltaic areas. These two items are presented in light of the rapidly changing and urbanizing world. The first item is mainly based on the work that was done with a great involvement of many specialists for the 6th and 7th World Water Forums and the second one on research by the author during the past decades. Copyright © 2017 John Wiley & Sons, Ltd.
Afficher plus [+] Moins [-]Determination of kinetic and thermodynamic parameters of food hydrocolloids/water interactions by means of thermal analysis and viscometry Texte intégral
2018
Valenta, Tomáš | Lapčíková, Barbora | Lapčík, Lubomír
The aim of this study was to determine thermal properties of pseudoplastic polysaccharides (guar gum, κ-carrageenan and xanthan gum) which find many applications as food hydrocolloids in food industry. There was an obvious relationship between thermal dependency of heats of fusion of hydrocolloids in powder form and activation parameters of hydrodynamic flow in solutions, respectively. Results of thermal analysis confirmed, that powder samples of hydrocolloids as typical foodstuffs of low moisture content less than 15 w% after room conditioning, exhibited varying ability to bind water as depending on their molecular structure. The peak temperature of the endothermic polysaccharide order-disorder phase transition process was found in the temperature range of 50–85 °C. It was influenced simultaneously by the applied heating rate and the samples moisture content. Studied samples moisture content was ranging between 9–40 w.% as was obtained after different conditioning. Observed reaction enthalpy (ΔH) associated with phase transition and water evaporation (proved by appropriate weight loss of the samples Δmw) was ranging from 140 to 670 J/g. Activation energy (Eₐ) of this process in powder samples was calculated from the kinetic parameters using three kinetic models developed by Friedman, Kissinger and model-free kinetics. The latter kinetic models were compared with the Arrhenius model, which was used to determine Eₐ of polysaccharide solutions on reflecting sensitivity of their molecular structure to the temperature and the solvent. According to the Arrhenius model, there were obtained the highest values of Eₐ for κ-carrageenan solutions, indicating the highest resistance of their molecular structure to temperature. This fact can be related to the observed the lowest value of the reaction enthalpy in the case of powder samples, suggesting that energy obtained during the order-disorder transition to change the carrageenan powder structure is limited. On the other hand, xanthan gum was the least temperature dependent sample; activation energy of xanthan solutions was only in the range of 2–6 kJ/mol. Concurrently, ΔH of xanthan powder was determined as the largest of all samples under study. In general, there was found an indirect relationship between activation energy of the solutions determined by viscometry and reaction enthalpy of the powders determined by thermal analysis. Results of the Arrhenius model also indicate that the energy necessary to promote viscous flow of solutions is higher for hydrocolloids in distilled water rather than in 0.07 M KCl aqueous solutions, suggesting the suppression of the polyelectrolyte effect. In both cases, Eₐ was substantially reduced by application of higher shear rate.
Afficher plus [+] Moins [-]The biogeochemical imprint of human metabolism in Paris Megacity: A regionalized analysis of a water-agro-food system Texte intégral
2018
Esculier, Fabien | Le Noë, Julia | Barles, Sabine | Billen, Gilles | Créno, Benjamin | Garnier, Josette | Lesavre, Jacques | Petit, Léo | Tabuchi, Jean-Pierre | Laboratoire Eau Environnement et Systèmes Urbains (LEESU) ; AgroParisTech-École nationale des ponts et chaussées (ENPC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12) | Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols (METIS) ; Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) | Géographie-cités (GC (UMR_8504)) ; Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS) | École nationale des ponts et chaussées (ENPC) | Agence de l'Eau Seine-Normandie | Direction Santé et Environnement (SIAAP) ; Syndicat interdépartemental pour l'assainissement de l'agglomération parisienne (SIAAP)
International audience | Megacities are facing a twofold challenge regarding resources: (i) ensure their availability for a growing urban population and (ii) limit the impact of resource losses to the environment. This paper focuses on two essential resources – nitrogen and phosphorus – and challenges their sustainable management in the water-agro-food system of Paris Megacity. An in-depth analysis of the nitrogen and phosphorus imprint of Paris Megacity was conducted, originally centered on human metabolism through consumption and excretion of these two elements. Upstream, the whole agricultural production that feeds Paris Megacity was scrutinized and nitrogen and phosphorus flows in the agro-system were fully documented. Downstream, the analysis of solid waste and wastewater management in Paris Megacity showed the fate of nitrogen and phosphorus imported into the city.
Afficher plus [+] Moins [-]Effect of water content on the dynamic measurement of dielectric properties of food snack pellets during microwave expansion Texte intégral
2018
Gutiérrez-Cano, José D. | Hamilton, Ian E. | Catalá-Civera, José M. | Bows, John | Peñaranda-Foix, Felipe L.
The evolution of dielectric properties of starch-based food pellets with different moisture contents was measured during microwave expansion to determine the effect of water content on the expansion dynamics.Dynamic dielectric measurements were found to be an excellent procedure to in situ monitor and characterize the different stages in the material transformation of food pellets during microwave expansion.Although the maximum bulk expansion of pellets was achieved at a moisture content of approximately 8% (wet basis), comparative analysis showed that a moisture content 10–11% produced the best results considering the tradeoff between the foaming and expansion temperature. This was due to the high expansion index and an expansion temperature that was sufficiently lower than the onset temperature for pellet scorching, which provides an operating window to maximize expansion and minimize the likelihood of burning.Dielectric measurements during microwave heating in short on/off cycles prior to pellet expansion suggested that the water was not as dielectrically bound for high moisture content pellets.
Afficher plus [+] Moins [-]Ecosystem tipping points due to variable water availability and cascading effects on food security in Sub‐Saharan Africa Texte intégral
2018
Muli, Celestine | Gerber, Nicolas | Sakketa, Tekalign Gutu | Mirzabaev, Alisher
The frequency, duration, and magnitude of extreme weather events such as droughts, floods, and variation in rainfall onset and cessation periods will continue to increase. Such stress may result in significant shifts in the functioning of ecosystems. As climate change affects the capacity of ecosystems to mitigate the effects of extreme events such as drought and floods, leading to disruptions in water supply and food production, or to the destruction of infrastructure, human well‐being is ultimately impacted. Chief among those impacts are those on the four dimensions of food security: food availability, accessibility, utilization, and stability. An interesting channel of impacts is through the observed and forecasted increase in the variability of water availability. This is said to cause uncertainty in agricultural production resulting in reduced productivity, food insecurity, weak economic growth and the widespread food poverty in Africa today. Due to overreliance on rain‐fed agriculture in Sub‐Saharan Africa, people usually engage in both temporary and permanent migration after consecutive years of bad harvests and reduced incomes from agriculture with migration acting as an adaptation strategy to climatic shocks. Food value chains can be significantly affected, something that the paper identifies as an area that requires further research mainly on the resilience of food value chains to water variability.
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