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Challenges in operationalizing the water–energy–food nexus Полный текст
2017
Liu, J. | Yang, H. | Cudennec, C. | Gain, A.K. | Hoff, H. | Lawford, R. | Qi, J. | Strasser, L de | Yillia, P.T. | Zheng, C.
Concerns about the water–energy–food (WEF) nexus have motivated many discussions regarding new approaches for managing water, energy and food resources. Despite the progress in recent years, there remain many challenges in scientific research on the WEF nexus, while implementation as a management tool is just beginning. The scientific challenges are primarily related to data, information and knowledge gaps in our understanding of the WEF inter-linkages. Our ability to untangle the WEF nexus is also limited by the lack of systematic tools that could address all the trade-offs involved in the nexus. Future research needs to strengthen the pool of information. It is also important to develop integrated software platforms and tools for systematic analysis of the WEF nexus. The experience made in integrated water resources management in the hydrological community, especially in the framework of Panta Rhei , is particularly well suited to take a lead in these advances.
Показать больше [+] Меньше [-]Food-energy-water nexus: A life cycle analysis on virtual water and embodied energy in food consumption in the Tamar catchment, UK Полный текст
2018
Salmoral, Gloria | Yan, Xiaoyu
Evaluations of food, energy and water (FEW) linkages are rapidly emerging in contemporary nexus studies. This paper demonstrates, from a food consumption perspective, the potential of life cycle thinking in understanding the complex and often “hidden” linkages between FEW systems. Our study evaluates the upstream virtual water and embodied energy in food consumption in the Tamar catchment, South West England, distinguishing between domestic production and imports origin. The study also evaluates key inputs, including virtual nutrients and animal feed, when tracking supply chain of food products. Based on current dietary patterns and food products selection, the catchment consumes annually 834 TJ, 17 hm³ and 244 hm³ of energy, blue water and green water, respectively. Tamar is not self-sufficient in terms of food and requires imports of food products, as well as imports of virtual nutrients and animal feed for local production. Consequently, 51% of the embodied energy and 88% blue and 45% green virtual water in food consumed within the catchment are imported. Most of the embodied energy (58%) and green virtual water (90%) are because of animal feed production, where nearly half of embodied energy (48%) and green virtual water (42%) come from imports. 92% of blue virtual water is used for irrigation and primarily happens elsewhere due to imports. Irrigation is the process that demands the largest amount of energy for the crop-based products, with 38% of their total energy demand, followed by fertilisers production (24%). Our study illustrates water and energy hotspots in the food life cycle and highlights potential FEW risks and trade-offs through trade. This is useful considering potential unexpected changes in trade under recent global socio-political trends. Currently available databases and software make LCA a key tool for integrated FEW nexus assessments.
Показать больше [+] Меньше [-]Prediction of water activity in food systems: a computer program for predicting water activity in multicomponent foods
1994
Vega-Mercado, H. | Barbosa-Canovas, G.V. (Washington State University, Pullman (USA). Dept. of Biological Systems Engineering) | Romanach, B.
La prediccion de actividad de agua (aw) mediante modelos matematicos, por lo general, esta limitada a disoluciones acuosas de electrolitos y no electrolitos. El efecto de componentes alimenticios tales como las grasas, las proteinas y la fibra no se considera cuando estos modelos se aplican a los alimentos. El valor estimado de aw en alimentos reales, generalmente, es mayor que el valor medido debido a que tanto las proteinas como las grasas ligan moleculas de agua. Por tal motivo, se desarrollo un programa para ordenadores que permite evaluar con buena precision el valor de actividad de agua, y que ademas es capaz de lo siguiente: (1) Predecir la aw a partir de modelos matematicos tales como Pitzer, Bromley, Norrish, Ross, Ferro-Chirife-Boquet y Ferro-Bermengui-Chirife. (2) Establecer un nivel de similitud entre alimentos de aw y composicion conocidos frente a alimentos a los que solo se conoce la composicion. (3) Definir un factor de desviacion en funcion del nivel de similitud anteriormente descrito en el que se considera la presencia de grasas, proteinas y fibra. El analisis de productos embutidos, para la primera iteraccion, dio un factor de desviacion de 1,07. En el caso de algunos productos azucarados, que incluyen gomas y pectinas, se encontro que el factor fue de 1,12. Una vez incrementado el numero de datos almacenados, los cuales dan apoyo al proceso iterativo de la prediccion de actividad de agua, el factor de desviacion converge rapidamente a uno.
Показать больше [+] Меньше [-]Water Management Reporting in the Agro-Food Sector in South Africa Полный текст
2017
Sánchez-Hernández, M Isabel | Robina-Ramírez, Rafael | De Clercq, Willem
The purpose of the study is to assess whether Corporate Social Responsibility regarding water is considered relevant for sustainability in companies related to agriculture in South Africa, considering that their impact directly influences public access to water. To accomplish this purpose, a qualitative approach was developed through the study of the 22 existing companies from the agriculture sector, food and beverages, forest and paper production, and Tobacco, which published their last integrated report within the Global Reporting Initiative framework. A thematic content analysis was carried out, involving the analysis of the written sustainability reports. For data analyses, ATLAS.ti 7.1 software was used to match the main aspects related to water management. Pragmatic advice for practitioners derives from the research results, considering that Corporate Social Responsibility in general—and sustainable water management in particular—represents an opportunity for companies to get competitive advantages in the market. The study also determines the best practices in the field in South Africa with benchmarking purposes.
Показать больше [+] Меньше [-]An integrated model to evaluate water-energy-food nexus at a household scale Полный текст
2017
Hussien, Wa'el A. | Memon, Fayyaz A. | Savic, Dragan A.
To achieve a sustainable supply and effectively manage water, energy and food (WEF) demand, interactions between WEF need to be understood. This study developed an integrated model, capturing the interactions between WEF at end-use level at a household scale. The model is based on a survey of 419 households conducted to investigate WEF over winter and summer for the city of Duhok, Iraq. A bottom-up approach was used to develop this system dynamics-based model. The model estimates WEF demand and the generated organic waste and wastewater quantities. It also investigates the impact of change in user behaviour, diet, income, family size and climate.The simulation results show a good agreement with the historical data. Using the model, the impact of Global Scenario Group (GSG) scenarios was investigated. The results suggest that the ‘fortress world’ scenario (an authoritarian response to the threat of breakdown) had the highest impact on WEF.
Показать больше [+] Меньше [-]Improving water quantity simulation & forecasting to solve the energy-water-food nexus issue by using heterogeneous computing accelerated global optimization method Полный текст
2018
Kan, Guangyuan | Zhang, Mengjie | Liang, Ke | Wang, Hao | Jiang, Yunzhong | Li, Jiren | Ding, Liuqian | He, Xiaoyan | Hong, Yang | Zuo, Depeng | Bao, Zhenxin | Li, Chaochao
With continuous population increase and economic growth, challenges on securing sufficient energy, water, and food supplies are amplifying. Water plays the most important role in the energy-water-food (E-W-F) nexus issue such as energy supply (clean hydropower energy generation), water supply (drinking water), and food supply (agricultural irrigation water). Therefore, water quantity simulation & forecasting become an important issue in E-W-F nexus problem. Water quantity simulation & forecasting model, such as rainfall-runoff (RR) hydrological model has become a useful tool which can significantly improve efficiency of the hydropower energy generation, water supply management, and agricultural irrigation water utilization. The accuracy and reliability of the water quantity simulation & forecasting model are significantly affected by the model parameters. Therefore, demand of effective and fast model parameter optimization tool for solving the E-W-F nexus problem increases significantly. The shuffled complex evolution developed at University of Arizona (SCE-UA) has been recognized as an effective global model parameter optimization method for more than 20years and is highly suited to solve the E-W-F nexus problem. However, the computational efficiency of the SCE-UA dramatically deteriorates when applied to complex E-W-F nexus problem. For the purpose of solving this conundrum, a fast parallel SCE-UA was proposed in this paper. The parallel SCE-UA was implemented on the novel heterogeneous computing hardware and software systems which were constituted by the Intel multi-core CPU, NVIDIA many-core GPU, and PGI Accelerator Visual Fortran (with OpenMP and CUDA). Performance comparisons between the parallel and serial SCE-UA were carried out based on two case studies, the Griewank benchmark function optimization and a real world IHACRES RR hydrological model parameter optimization. Comparison results indicated that the parallel SCE-UA outperformed the serial one and has good application prospects for solving the water quantity simulation & forecasting model parameter calibration in the E-W-F nexus problem.
Показать больше [+] Меньше [-]Active Image-Assisted Food Records in Comparison to Regular Food Records: A Validation Study against Doubly Labeled Water in 12-Month-Old Infants Полный текст
2018
Johansson, Ulrica | Venables, Michelle | Öhlund, Inger | Lind, Torbjörn
Overreporting of dietary intake in infants is a problem when using food records (FR), distorting possible relationships between diet and health outcomes. Image-assisted dietary assessment may improve the accuracy, but to date, evaluation in the pediatric setting is limited. The aim of the study was to compare macronutrient and energy intake by using an active image-assisted five-day FR against a regular five-day FR, and to validate image-assistance with total energy expenditure (TEE), was measured using doubly labeled water. Participants in this validation study were 22 healthy infants randomly selected from the control group of a larger, randomized intervention trial. The parents reported the infants’ dietary intake, and supplied images of main course meals taken from standardized flat-surfaced plates before and after eating episodes. Energy and nutrient intakes were calculated separately using regular FR and image-assisted FRs. The mean (± standard deviations) energy intake (EI) was 3902 ± 476 kJ/day from the regular FR, and 3905 ± 476 kJ/day from the FR using active image-assistance. The mean EI from main-course meals when image-assistance was used did not differ (1.7 ± 55 kJ, p = 0.89) compared to regular FRs nor did the intake of macronutrients. Compared to TEE, image-assisted FR overestimated EI by 10%. Without validation, commercially available software to aid in the volume estimations, food item identification, and automation of the image processing, image-assisted methods remain a more costly and burdensome alternative to regular FRs in infants. The image-assisted method did, however, identify leftovers better than did regular FR, where such information is usually not readily available.
Показать больше [+] Меньше [-]Critical reflections on Water-Energy-Food Nexus in Computable General Equilibrium models: A systematic literature review Полный текст
2021
Bardazzi, Elisa | Bosello, Francesco
The paper analyses how the Water-Energy-Food Nexus is treated in Computable General Equilibrium (CGE) models, discussing their design, importance and possible ways of improvement. The analysis of their structure is critical for evaluating their potential efficiency in understanding the Nexus, which will be particularly effective for gauging the importance of the topic, the reciprocal dependency of its elements and the expected macroeconomic, demographic and climatic pressures that will act on its components. General equilibrium models can be useful devices to this end, as they are specifically built to track interdependencies and transmission effects across sectors and countries. Nevertheless, the review showed that most CGEs in the literature struggle to represent the competing water uses across sectors and, in particular, those concerning the energy sector. Therefore, it highlights the need to resolve this issue as a necessary step toward improving future research.
Показать больше [+] Меньше [-]Using a Concentrate of Phenols Obtained from Olive Vegetation Water to Preserve Chilled Food: Two Case Studies Полный текст
2016
Fasolato, Luca | Cardazzo, Barbara | Balzan, Stefania | Carraro, Lisa | Andreani, Andrea Nadia | Taticchi, Agnese | Yambo,
Phenols are plant metabolites characterised by several interesting bioactive properties such as antioxidant and bactericidal activities. In this study the application of a phenols concentrate (PC) from olive vegetation water to two different fresh products – gilt-head seabream (Sparus aurata) and chicken breast – was described. Products were treated in a bath of PC (22 g/L; chicken breast) or sprayed with two different solutions (L1:0.75 and L2:1.5 mg/mL; seabream) and then stored under refrigeration conditions. The shelf life was monitored through microbiological analyses – quality index method for seabream and a specific sensory index for raw breast. The secondary products of lipid-peroxidation of the chicken breast were determined using the thiobarbituric acid reactive substances (TBARs) test on cooked samples. Multivariate statistical techniques were adopted to investigate the impact of phenols and microbiological data were fitted by DMfit software. In seabream, the levels of PC did not highlight any significant difference on microbiological and sensory features. DMfit models suggested an effect only on H₂S producing bacteria with an increased lag phase compared to the control samples (C: 87 h vs L2: 136 h). The results on chicken breast showed that the PC bath clearly modified the growth of Pseudomonas and Enterobacteriaceae. The phenol dipping was effective in limiting lipid-peroxidation (TBARs) after cooking. Treated samples disclosed an increase of shelf life of 2 days. These could be considered as preliminary findings suggesting the use of this concentrate as preservative in some fresh products.
Показать больше [+] Меньше [-]Water for food, water for birds: How to manage conflicting rural-natural interfaces? Deepening on the socio-ecological system of El Hondo Natural Park (Alicante, Spain) Полный текст
2021
Ricart, Sandra | Rico Amorós, Antonio M.
As socio-ecological systems, coastal wetlands constitute great economic, cultural, recreational and environmental value. However, due to rapid urbanisation and intensification of agricultural activities, these hybrid systems are continuously degraded, generating several ecological and social problems. This paper aims to deepen how agriculture-nature interactions and actor behaviour affect coastal wetlands' management while conditioning decision-making processes. El Hondo Natural Park (Alicante, Spain) is the selected case study in which 15 key stakeholders from the public administration, the rural community, and the civil society are selected. Data were collected between April and June 2018 through semi-structured interviews and analysed following the Grounded Theory principles and by computer-assisted qualitative and mixed methods data software, MAXQDA®. Results revealed how the rural community and civil society members agree on El Hondo Natural Park's cultural function, conceived as a mechanism to preserve local identity, protecting traditional agricultural practices and rural heritage. However, El Hondo Natural Park's origin and management generated discussion, including topics such as the natural park’ declaration, public investment, and participation in decision-making processes (especially due to the lack of transparency and information). Furthermore, main challenges have been identified: farmers' survival, water scarcity and water quality standards, and social recognition and promotion of the natural park. Researchers and relevant authorities can use obtained results to customize their interventions based on previous and well-structured knowledge of how socio-ecological systems are perceived and which past or new conflicts generate frustration among confronted stakeholders' demands.
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