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Proceedings of the 2010 Water for Food Conference
2010
Norby, M. (ed.) | Nebraska Univ., Lincoln (USA). Office of Research and Economic Development | Water for Food Conference Lincoln, NE (USA) 2-5 May 2010 eng | Klucas, G.
Avaliação do bombeamento de água em um sistema alimentado por painéis fotovoltaicos Water pumping in a system fed by photovoltaic panels Полный текст
2009
Roger N. Michels | Reinaldo P. Ricieri | Estor Gnoatto | Samuel N. M. de Sousa | Suedêmio de Lima Silva | Marcos Fischborn
O presente trabalho foi desenvolvido com a finalidade de avaliar um sistema de bombeamento de água acionado por painéis fotovoltaicos instalados nas dependências da Universidade Tecnológica Federal do Paraná, Câmpus Medianeira - PR. O município está localizado no oeste paranaense (25º17'43" S; 54º03'38" e 500,7 m). O sistema trabalhou em situação real de funcionamento, bombeando água à altura de 20 m. Foram coletados dados de fevereiro a novembro de 2005; utilizou-se coletor de dados computadorizado da Campbell Scientific INC. , que possibilitou adquirir e armazenar os dados de irradiância solar no plano do painel, tensão e corrente gerada, temperatura no painel e vazão. Por meio de cálculos, obtiveram-se os valores de potência e eficiência do sistema. O solstício de inverno apresentou eficiência de 9,58% com bombeamento diário de 2.056 litros, enquanto o solstício de verão apresentou eficiência de 9,07% com bombeamento diário de 2.377 litros. A maior eficiência nos dias de inverno está ligada às menores temperaturas se comparada aos dias de verão, e o fator que provocou a maior vazão de água bombeada nos dias de verão está atrelado ao tempo de insolação, que é maior se comparado aos dias de inverno.<br>The main objective of this paper is to evaluate a water pumping system powered by photovoltaic panels installed at Federal Technological University of Paraná - UTFPR, in Medianeira, State of Paraná, Brazil. The city is located at the West of Paraná (25º17'43"; 54º03'38" and 500.7 meters - 1,642.72 feet). The system operated in a real working situation, pumping water to 20 meters (65.62 feet) of elevation. The data were collected, from February 2005 to November 2005, by means of a computerized data collector made by Campbell Scientific Inc that made possible to acquire and store irradiance values in the panel plane, generated current and voltage, panel temperature and outflow. Through calculations, the power and the system efficiency were obtained. Winter solstice showed 9.58% efficiency with daily pumping of 2,056 liters (543.14 gallons) whereas summer solstice confirmed 9.07% efficiency with daily pumping of 2,377 liters (627.86 gallons). The higher efficiency in winter days is associated to the lowest temperature in those days compared to summer days, and the factor that led to a larger pumped water outflow in the summer days was related to solar insolation time that is longer if compared to winter days.
Показать больше [+] Меньше [-]Sefficiency (sustainable efficiency) of water–energy–food entangled systems Полный текст
2016
Haie, Naim
Water–energy–food (WEF) entanglement is intensifying and technology is being presented as a crucial solution. But time and again the implemented alternative manifests results contrary to the objectives of design or management. To advance water security, transparent and complete input–output methodologies are needed. Here, a Sefficiency (sustainable efficiency) framework is used to reason through systemic analyses of options for WEF schemes by using water quantity within a comprehensive water balance, and quality and benefits in a multilevel water-use system. An energy regime (cost and normalized functions) and Sefficiency compute performance of four cases that show flaws both conceptually and practically in current policy and scientific tendencies.
Показать больше [+] Меньше [-]Towards the More Efficient Use of Water and Nutrients in Food Legume Cropping Полный текст
2014
n. p. saxena | masood ali | r. dahan | j. p. mishra
Nutrient imbalance and soil moisture stress are the major abiotic constraints limiting productivity of cool season food legumes. These constraints are more pronounced in the semi-arid tropics and sub-tropics which are the principal production zones of chickpea, lentil and faba bean. The legumes are generally grown on residual moisture as a mono crop and consequently face drought especially during the reproductive phase. In recent years, chickpea, lentil, peas and faba bean have been grown in some areas with an irrigated/assured water supply under intensive cropping to sustain cereal based systems. An increased water supply favourably influences productivity in dry environments. Faba bean, French beans and peas show a relatively better response to irrigation. The pod initiation stage is considered most critical with respect to moisture stress. Excessive moisture often has a negative effect on podding and seed yield. Eighty to ninety percent of the nitrogen requirements of leguminous crops is met from N2 fixation hence a dose of 15?25 kg N ha-1 has been recommended. However, in new cropping systems like rice-chickpea, higher doses of 30?40 kg N ha-1 are beneficial. Phosphorus deficiency is wide spread and good responses occur to 20 to 80 kg P2O5 ha-1, depending on the nutrient status of soil, cropping systems and moisture availability. Response to potassium application is localized. The use of 20?30 kg S ha-1 and some of the micronutrients such as Zn, B, Mo and Fe have improved productivity. Band placement of phosphatic fertilizers and use of bio-fertilizers has enhanced the efficiency of applied as well as native P. Foliar applications of some micronutrients have been effective in correcting deficiencies. Water use efficiency has been improved with some management practices such as changed sowing time, balanced nutrition, mulching and tillage | Masood Ali, R. Dahan, J. P. Mishra, N. P. Saxena, 'Towards the More Efficient Use of Water and Nutrients in Food Legume Cropping', Linking Research and Marketing Opportunities for Pulses in the 21st Century, vol. 34, pp.355-368, Springer Netherlands, 2014
Показать больше [+] Меньше [-]Development of standard method for investigation of Clostridium perfringens in food, water and beverage
1995
Than-yalak Ninbodee | Sinee Juntarapootirat | Sompob Valtanamanee
Selective medium for investigation of C. perfringens in food, water and beverage was developed to substitute for FM-CW Agar due to no production of this medium in Japan. Five formulas of media: Clostridium welchii Brain Heart Infusion Agar (CWB), Clostridium welchii Agar (CWA), Loctose Egg-Yolk Agar (LEY), Liver Veal Agar (LV) and Modified Brain Heart Infusion Agar (Mod.BHI), were selected in this research. The quality and efficiency of these media was compared to FM-CW by using the reference standard culture of C. perfringens. The results showed that Mod.BHI is the most effective medium for observing the appearance of colony, the lecithinase reaction in egg yolk and Nagler reaction of organism. Therefore it was found that the Mod.BHI must be adjusted pH to 7.6 and boiled for sterilization then neomycin 400/ug/m/ was added. The developed medium and FM-CW were used to investigate C. perfringens, isolated from 35 samples of food, water and beverage and C. bifermentans isolated from 5 samples of food. The result showed that the developed medium, Mod. BHI, can be used to investigate C. perfringens in stead of FM-CW Agar.
Показать больше [+] Меньше [-]Avaliação do bombeamento de água em um sistema alimentado por painéis fotovoltaicos Полный текст
2009
Michels, Roger N.(Universidade Tecnológica Federal do Paraná) | Ricieri, Reinaldo P.(Universidade Estadual do Oeste do Paraná) | Gnoatto, Estor(Universidade Tecnológica Federal do Paraná) | Sousa, Samuel N. M. de(Universidade Estadual do Oeste do Paraná) | Silva, Suedêmio de Lima(Universidade Federal Rural do Semiárido) | Fischborn, Marcos(Universidade Tecnológica Federal do Paraná)
O presente trabalho foi desenvolvido com a finalidade de avaliar um sistema de bombeamento de água acionado por painéis fotovoltaicos instalados nas dependências da Universidade Tecnológica Federal do Paraná, Câmpus Medianeira - PR. O município está localizado no oeste paranaense (25º17'43" S; 54º03'38" e 500,7 m). O sistema trabalhou em situação real de funcionamento, bombeando água à altura de 20 m. Foram coletados dados de fevereiro a novembro de 2005; utilizou-se coletor de dados computadorizado da Campbell Scientific INC. , que possibilitou adquirir e armazenar os dados de irradiância solar no plano do painel, tensão e corrente gerada, temperatura no painel e vazão. Por meio de cálculos, obtiveram-se os valores de potência e eficiência do sistema. O solstício de inverno apresentou eficiência de 9,58% com bombeamento diário de 2.056 litros, enquanto o solstício de verão apresentou eficiência de 9,07% com bombeamento diário de 2.377 litros. A maior eficiência nos dias de inverno está ligada às menores temperaturas se comparada aos dias de verão, e o fator que provocou a maior vazão de água bombeada nos dias de verão está atrelado ao tempo de insolação, que é maior se comparado aos dias de inverno. | The main objective of this paper is to evaluate a water pumping system powered by photovoltaic panels installed at Federal Technological University of Paraná - UTFPR, in Medianeira, State of Paraná, Brazil. The city is located at the West of Paraná (25º17'43"; 54º03'38" and 500.7 meters - 1,642.72 feet). The system operated in a real working situation, pumping water to 20 meters (65.62 feet) of elevation. The data were collected, from February 2005 to November 2005, by means of a computerized data collector made by Campbell Scientific Inc that made possible to acquire and store irradiance values in the panel plane, generated current and voltage, panel temperature and outflow. Through calculations, the power and the system efficiency were obtained. Winter solstice showed 9.58% efficiency with daily pumping of 2,056 liters (543.14 gallons) whereas summer solstice confirmed 9.07% efficiency with daily pumping of 2,377 liters (627.86 gallons). The higher efficiency in winter days is associated to the lowest temperature in those days compared to summer days, and the factor that led to a larger pumped water outflow in the summer days was related to solar insolation time that is longer if compared to winter days.
Показать больше [+] Меньше [-]The nexus across water, energy, land and food (WELF): potential for improved resource use efficiency? Полный текст
2013
ringler claudia | lawford richard | http://orcid.org/0000-0002-8266-0488 ringler claudia | bhaduri anik
Ringler Claudia, 'The nexus across water, energy, land and food (WELF): potential for improved resource use efficiency?', Current Opinion in Environmental Sustainability 5, IFPRI, 2013 | CGIAR Research Program on Water, Land and Ecosystems (WLE)
Показать больше [+] Меньше [-]A model to integrate and assess water-energy-food nexus performance: South Africa case study Полный текст
2020
t. mabhaudhi | luxon nhamo | s. mpandeli
The main limiting factor impeding the operationalisation of the WEF nexus has been lack of metrics and tools to translate the concept into a fully-fledged operational framework to support policy and decision-making. This study developed a WEF nexus model by (i) defining WEF nexus sustainability indicators, and (ii) calculating composite indices for those indicators to establish numerical relationships among WEF nexus resources using South Africa as a case study. The composite indices show WEF nexus performance as well as monitoring and evaluation of WEF resources management. The indicators were integrated through the Analytic Hierarchy Process (AHP) in a multicriteria decision-making (MCDM). The established quantitative relationships indicate resource utilisation, management and performance through a spider graph to illustrate WEF nexus performance, providing a general overview of the level of interactions, interrelationships and inter-connectedness of resources. The shape of the spider graph is determined by the level of the interdependencies and interactions among the WEF nexus sectors, whose management is viewed either as sustainable or unsustainable depending on the classification of the developed integrated index. The spider graph for South Africa showed an over-emphasis on food self-sufficiency and water productivity at the expense of other sectors. The deformed shape of the spider graph is a demonstration of the sectoral or �??silo�?� approach in resource management. The calculated integrated WEF nexus index of 0.203 for South Africa classified the country under the low sustainability category. The developed model is a decision support tool that provides evidence for interventions in priority areas. The model demonstrates the capabilities of the WEF nexus to evaluate synergies and trade-offs in a systematic and integrated way to increases efficiency and productivity in resource management for sustainable development | Luxon Nhamo, T. Mabhaudhi, S. Mpandeli, 'A model to integrate and assess water-energy-food nexus performance: South Africa case study', pp.10p, 2020
Показать больше [+] Меньше [-]Managing Scarce Water Resources in Irrigated Agri-Food Systems of Central Asia Two Case Studies Полный текст
2017
Irrigated agriculture is the backbone of Central Asian economies. Therefore, efficient irrigation water management is of crucial importance to the sustainable crop production in the region. Presented here are two studies aiming to improve agricultural water productivity â?? ET-based irrigation scheduling in Uzbekistan; and valuation of ecosystem services in Kazakhstan. The ET-based irrigation scheduling method has potential to replace subjective daily water management decisions at Water Users Association level with crop water demand-based decisions to improve water-use efficiency. Results from a two year study show that there can be a 32-35% saving of water when irrigation is applied using the ET-based scheduling method. The pilot plots are representative of 38% of irrigated area in Fergana Valley (241,407ha) and 50% in Khorezm (137,500ha) area. If this methodology is widely adopted, large amounts of water can be saved which can be diverted for other purposes. Flood irrigation of cotton is practiced on 128,000ha in the Bugunski Reservoir watershed of Kazakhstan. This practice is unsustainable due to seasonal unavailability in water supply and depletion of river discharges that were historically important at maintaining water levels downstream in nearby wetlands and the Aral Sea. Farmer surveys were used along with RIOS and SWAT modeling to evaluate alternative irrigation practices and cropping systems that can conserve water from the Bugunski Reservoir while maintaining farmer incomes. Simulations show significant reductions in irrigation water demand in the alternative scenario relative to the baseline scenario. Under baseline flood irrigation of cotton, annual irrigation demand was 928 MCM/yr averaged over the 32 year climatic record simulated. Irrigation demand decreased by 38% to 573 MCM/yr when 40,439ha of flood irrigated cotton was converted to drip irrigated cotton, sprinkler irrigated alfalfa and drip irrigated grapes. This represents a savings of 355 MCM/yr in water extracted from irrigation canals and groundwater wells | Vinay Nangia. (7/11/2016). Managing Scarce Water Resources in Irrigated Agri-Food Systems of Central Asia Two Case Studies. Phoenix, United States: American Society of Agronomy.
Показать больше [+] Меньше [-]Planning regional-scale water-energy-food nexus system management under uncertainty: An inexact fractional programming method Полный текст
2022
Huang, Kai | Dai, Liming | Yu, Lei | Fan, Yurui | Huang, Guohe | Xiao, Yao | Wu, Qingsong
In this study, an inexact fractional programming method is employed for planning the regional-scale water-energy-food nexus (WEFN) system. The IFP cannot only deal with uncertainties expressed as interval parameters, but also handle conflicts among multiple decision stakeholders. The IFP approach is then applied to planning the WEFN system of Henan Province, China. An IFP-WEFN model has been established under consideration of various restrictions related to water and energy availability, as well as food demand. Solutions of the planting areas for different crops in different periods have been generated. The results suggested that there would be a significant increase for vegetable cultivation with an increasing rate of 24.4% and 30% respectively for the conservative and advantageous conditions, followed by the fruit cultivation. In comparison, the planting area of cotton would be decreased with a decreasing rate of 21.2%, and there would also be an explicit decrease for rice cultivation. These results can help generate a desired planting scheme in order to achieve a maximized unit benefit with respect to the water utilization. Comparison between the IFP-WEFN model and the ILP-WEFN model indicates that, even though a slightly lower benefit is obtained from IFP-WENF model, it can result in a higher unit benefit than the planting scheme from ILP-WEFN model. Consequently, the IFP-WEFN model can help decision-makers identify the sustainable agricultural water resources management schemes with a priority of water utilization efficiency.
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