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Nutritional Water Productivity and Global Food Security
2011
Water is life and is one of the major inputs for agriculture. Earth has a finite supply of fresh water and therefore, demands that every drop of annual rainfall should be conserved and judiciously utilized for production and postproduction agriculture to get maximum nutrients per unit of water. The concept of water productivity in agriculture is now shifting from harvest index per unit of land and water to nutrients (protein, carbohydrate, fat, etc.) produced per unit of water. This varies with food commodities and locations. For example, the total dietary energy produced by potato, maize, peanut, wheat, milk, egg and beef using one m³ of water are about 5600 kcal, 3800 kcal, 2300 kcal, 2280 kcal, 660 kcal, 520 kcal and 100 kcal, respectively. Similarly, the production of protein using one m³ of water by potato, peanut, maize, wheat, egg, milk, chicken, and beef are 150 g, 111 g, 77 g, 74 g, 41 g, 40 g, 33 g and 10 g, respectively. This paper describes the water nutrient productivity of some of the crops and livestock products and suggests as to how to provide food and nutritional security through an appropriate and balanced diet design, to the maximum number of people of the world from the limited and dwindling land, water and bio resources.
اظهر المزيد [+] اقل [-]Land-Water-Food Nexus and indications of crop adjustment for water shortage solution النص الكامل
2018
Ren, Dandan | Yang, Yonghui | Yang, Yanmin | Richards, Keith | Zhou, Xinyao
While agriculture places the greatest demand on water resources, increasing agricultural production is worsening a global water shortage. Reducing the cultivation of water-consuming crops may be the most effective way to reduce agricultural water use. However, when also taking food demand into consideration, sustaining the balance between regional water and food securities is a growing challenge. This paper addresses this task for regions where water is unsustainable for food production (Beijing-Tianjin-Hebei Region for example) by: (i) assessing the different effects of wheat and maize on water use; (ii) analyzing virtual water and virtual land flows associated with food imports and exports between Beijing-Tianjin-Hebei and elsewhere in China; (iii) identifying sub-regions where grain is produced using scarce water resources but exported to other regions; and (iv) analyzing the potentiality for mitigating water shortage via Land-Water-Food Nexus. In the Beijing-Tianjin-Hebei Region, the study reveals that 29.76 bn m3 of virtual water (10.81 bn m3 of blue virtual water) are used by wheat and maize production and 8.77 bn m3 of virtual water used in nearly 2 million ha of cropland to overproduce 12 million ton of maize for external food consumption. As an importing-based sub-region with high population density, Beijing & Tianjin imported mostly grain (wheat and maize) from Shandong Province. Then, Hebei Province, as an exporting-based sub-region with severe water shortage, overproduced too much grain for other regions, which aggravated the water crisis. To achieve an integrated and sustainable development of the Beijing-Tianjin-Hebei Region, Hebei Province should stop undertaking the breadbasket role for Beijing & Tianjin and pay more attention to groundwater depletion. The analysis of the Land-Water-Food Nexus indicates how shifts in cultivated crops can potentially solve the overuse of water resources without adverse effects on food supply. It also provides meaningful information to support policy decisions about regional cropping strategies.
اظهر المزيد [+] اقل [-]Food and water scenarios for the Karkheh River Basin, Iran النص الكامل
2010
Marjanizadeh, S. | Fraiture, Charlotte de | Loiskandl, W.
Increasing population and income and a wheat self-sufficiency policy are already stressing Iran's strategic Karkeh River Basin. Examining three scenarios to the year 2025, the authors of this study find: (1) business as usual leads to an aggravation of groundwater overdraft and may jeopardize the ecosystem services provided by the Hawr Al Azim marsh area; (2) giving priority to environmental flow requirements and restoring groundwater tables leads to a shortfall in wheat production; but (3) reducing agricultural water demand could maintain a certain level of food production. Appropriate policy could minimize the tradeoffs between food self-sufficiency, sustainable water use and farmers' income.
اظهر المزيد [+] اقل [-]Cereal protein-based nanoparticles as agents stabilizing air–water and oil–water interfaces in food systems النص الكامل
2019
Wouters, Arno GB | Delcour, Jan A.
There has been a recent surge of interest in the use of food-grade nanoparticles (NPs) for stabilizing food foams and emulsions. Cereal proteins are a promising raw material class to produce such NPs. Studies thus far have focused mostly on wheat gliadin and maize zein-based NPs. The former are effective interfacial stabilizing agents, while the latter due to their high hydrophobicity generally result in poor interfacial stability. Several strategies to modify the surface properties of wheat gliadin and maize zein NPs have been followed. In many instances, this resulted in improved foam or emulsion stability. Nonetheless, future efforts should be undertaken to gain fundamental insights in the interfacial behavior of NPs, to further explore NP surface modification strategies, and to validate the use of NPs in actual food systems.
اظهر المزيد [+] اقل [-]National water, food, and trade modeling framework: The case of Egypt النص الكامل
2018
Abdelkader, A. | Elshorbagy, A. | Tuninetti, M. | Laio, F. | Ridolfi, L. | Fahmy, H. | Hoekstra, A.Y.
This paper introduces a modeling framework for the analysis of real and virtual water flows at national scale. The framework has two components: (1) a national water model that simulates agricultural, industrial and municipal water uses, and available water and land resources; and (2) an international virtual water trade model that captures national virtual water exports and imports related to trade in crops and animal products. This National Water, Food & Trade (NWFT) modeling framework is applied to Egypt, a water-poor country and the world's largest importer of wheat. Egypt's food and water gaps and the country's food (virtual water) imports are estimated over a baseline period (1986–2013) and projected up to 2050 based on four scenarios. Egypt's food and water gaps are growing rapidly as a result of steep population growth and limited water resources. The NWFT modeling framework shows the nexus of the population dynamics, water uses for different sectors, and their compounding effects on Egypt's food gap and water self-sufficiency. The sensitivity analysis reveals that for solving Egypt's water and food problem non-water-based solutions like educational, health, and awareness programs aimed at lowering population growth will be an essential addition to the traditional water resources development solution. Both the national and the global models project similar trends of Egypt's food gap. The NWFT modeling framework can be easily adapted to other nations and regions.
اظهر المزيد [+] اقل [-]Modeling water management and food security in India under climate change النص الكامل
2014
Islam, A. | Shirsath, P. B. | Kumar, S. N. | Subash, N. | Sikka, A. K. | Aggarwal, Pramod Kumar
Climate change and variability will impact water availability and the food security of India. Trend analyses of historical data indicate an increase in temperature and changes in rainfall pattern in different parts of the country. The general circulation models (GCMs) also project increased warming and changes in precipitation patterns over India. This chapter presents examples of model applications in water management and crop yield simulation in India, focusing on climate change impact assessment. Simulation models have been successfully applied for rotational water allocation, deficit irrigation scheduling, etc. in different canal commands. Application of a universal soil loss equation in a distributed parametric modeling approach by partitioning watershed into erosion response units suggests that by treating only 14% of the watershed area, a 47% reduction in soil loss can be achieved. Simulation studies conducted using different hydrological models with different climate change projections and downscaling approaches showed varied hydrological responses of different river basins to the future climate change scenarios, depending on the hydrological model, climate change scenarios, and downscaling approaches used. Crop yield modeling showed decreases in irrigated and rainfed rice (Oryza sativa L.) yields under the future climate change scenarios, but the decrease is marginal for rainfed rice. Maize (Zea mays L.) yields in monsoon may be adversely affected by a rise in atmospheric temperature, but increased rain can partly offset those losses. Wheat (Triticum aestivum L.) yields are likely to be reduced by 6 to 23% and 15 to 25% during the 2050s and 2080s, respectively. A combined bottom-up participatory process and top-down integrated modeling tool could provide valuable information for locally relevant climate change adaptation planning.
اظهر المزيد [+] اقل [-]Modelling nutrient flows in a simplified local food-energy-water system النص الكامل
2018
Yao, Yuxi | Martinez-Hernandez, Elias | Yang, Aidong
Sustainable use and management of nutrients is an important issue for food, energy and water systems. The close connections between the three systems, reflected by the “nexus” concept, warrant an integrated approach to nutrients management across the nexus. In this paper, dynamic modelling of nutrient flows in a local food-energy-water system is presented and applied to a simplified case study. The model was used to simulate several scenarios affecting nitrogen flows and stocks to assess the impact of a) the level of local wheat production, b) the selection of energy generation technology, and c) the management of available nutrient resources (digestate and straws). The simulation results showed that varying the proportion of locally produced wheat significantly affects the surface runoff and the nitrogen content in a local water body, with the latter increasing by nearly 70% in 50 years if about half of the wheat consumed is produced locally as opposed to being 100% imported. The introduction of anaerobic digestion as an energy generation option helps to supply more electricity, reduce the imported fertiliser, and also significantly reduce the landfilled nitrogen nutrient by up to 60 times, due to the reuse of the anaerobic digestate. On the other hand, a balanced consideration should be given between using the straw as fertiliser and as feedstock for energy generation. This work offers a first analysis of the food-energy-water nexus with a focus on nutrient flows and stocks. The modelling approach has the potential to inform holistic decision making with respect to nutrient usage, efficiency and the related environmental impact in the design of a local system for meeting the demand for food, energy and water.
اظهر المزيد [+] اقل [-]Arab Development Symposium I : Food and Water Security in the Arab World النص الكامل
2014
Rouis, Mustapha | Limam, Imed
Recognizing the importance of policy debate and knowledge sharing in the field of development, the Arab Fund for Economic and Social Development and the World Bank (Middle East and North Africa Region) agreed in March 2010 to hold joint high-level development seminars around issues pertaining to the Arab World. These were to be known as the Arab Development Symposia (ADS) and will be held on a regular basis, every 18 months or so, at the Arab Fund premises in Kuwait. The goal was to provide an opportunity for policymakers, practitioners and academicians to share ideas and experiences on topics which are high on the Arab development agenda. As such, the ADS series complement other fora for research and knowledge sharing and dissemination such as the Economic Research Forum (ERF) and the Research Initiative for Arab Development (RIAD).
اظهر المزيد [+] اقل [-]Arab Development Symposium I : Food and Water Security in the Arab World
2014
Rouis, Mustapha | Limam, Imed
Recognizing the importance of policy debate and knowledge sharing in the field of development, the Arab Fund for Economic and Social Development and the World Bank (Middle East and North Africa Region) agreed in March 2010 to hold joint high-level development seminars around issues pertaining to the Arab World. These were to be known as the Arab Development Symposia (ADS) and will be held on a regular basis, every 18 months or so, at the Arab Fund premises in Kuwait. The goal was to provide an opportunity for policymakers, practitioners and academicians to share ideas and experiences on topics which are high on the Arab development agenda. As such, the ADS series complement other fora for research and knowledge sharing and dissemination such as the Economic Research Forum (ERF) and the Research Initiative for Arab Development (RIAD).
اظهر المزيد [+] اقل [-]Blue Water and the Consequences of Alternative Food Security Policies in the Middle East and North Africa for Water Security النص الكامل
2013
Larson, Donald F.
In the Middle East and North Africa, food security and water security are tightly entwined. In particular, choices about the extent to which food security policies rely on trade rather than domestically produced staples have stark consequences for the region's limited water resources. This paper builds on previous modeling results comparing the cost and benefits of policies to protect consumers against surging international wheat prices, and expands the analysis to consider the consequences of the policies for water resources. A self-sufficiency policy is analyzed as well. Results suggest that trade-based food security policies have no significant effect on the sustainability of water resources, while the costs of policies based on self-sufficiency for water resources are high. The analysis also shows that while information about the water footprint of alternative production systems is helpful, a corresponding economic footprint that fully measures the resource cost of water is needed to concisely rank alternative policies in economic terms that are consistent with sustainable outcomes.
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