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Aigua i producció d’aliments. Per què els cultius necessiten aigua? | Water and food production. Why crops need water? | Agua y producción de alimentos. ¿Por qué los cultivos necesitan agua? Полный текст
2021
Girona, Joan | Villar, Josep M.
Aquest article explica el paper de l’aigua en el comportament general de les plantes i, en concret, la seva rellevància en l’agricultura, amb l’objectiu que els lectors, no especialitzats en aspectes fisiològics, entenguin la importància del recurs de l’aigua en la producció d’aliments i béns. Per a fer-ho, s’analitzen els conceptes més rellevants que governen el funcionament de l’aigua a la planta i la relació amb els processos més lligats a la producció (fotosíntesi i creixement vegetatiu). Per a il·lustrar aquests conceptes es presenten alguns exemples agronòmics relacionats amb la sensibilitat estacional al dèficit hídric, l’eficiència en l’ús de l’aigua o la dependència de la producció d’aliments a la disponibilitat d’aigua.PARAULES CLAU: aigua, producció d’aliments, fisiologia vegetal, potencial hídric, fotosíntesi, transpiració, sensibilitat estacional al dèficit hídric. | This paper explains the role of water in the general behaviour of plants and more specifically its importance in agriculture, with the aim to let the reader who is not specialized in physiological aspects understand the function of water in the production of food and goods. To do this, the most significant concepts regulating the behaviour of water inside the plant have been analysed, together with the relationship of water with the processes most closely linked to production (photosynthesis and vegetative growth). Likewise, to illustrate these concepts, some agronomic examples are given in relation to seasonal sensitivity to water deficit, water use efficiency, and the dependence of food production on water availability.KEYWORDS: water, food production, plant physiology, water potential, photosynthesis, transpiration, seasonal sensitivity to water deficit. | Este artículo explica el papel del agua en el comportamiento general de las plantas y, en concreto, su relevancia en la agricultura, con el objetivo de que los lectores, no especializados en aspectos fisiológicos, puedan entender la importancia del recurso del agua en la producción de alimentos y bienes. Para ello, se han analizado los conceptos más destacados que gobiernan el funcionamiento del agua en la planta y su relación con los procesos más vinculados a la producción (fotosíntesis y crecimiento vegetativo). Para ilustrar estos conceptos se presentan algunos ejemplos agronómicos relacionados con la sensibilidad estacional al déficit hídrico, la eficiencia en el uso del agua o la dependencia de la producción de alimentos a la disponibilidad de agua.PALABRAS CLAVE: agua, producción de alimentos, fisiología vegetal, potencial hídrico, fotosíntesis, transpiración, sensibilidad estacional al déficit hídrico.
Показать больше [+] Меньше [-]Oil-in-water food emulsions stabilized by tuna proteins | Emulsiones alimentarias aceite-en-agua estabilizadas con proteínas de atún Полный текст
2010
Ruiz Márquez, D., Universidad de Huelva (España). Facultad de Ciencias Experimentales | Partal, P., Universidad de Huelva (España). Facultad de Ciencias Experimentales | Franco, J.M., Universidad de Huelva (España). Facultad de Ciencias Experimentales | Gallegos, C., Universidad de Huelva (España). Facultad de Ciencias Experimentales
El presente trabajo se ha centrado en el desarrollo de emulsiones alimentarias aceite-en-agua estabilizadas con proteínas de atún. Específicamente, se ha analizado la influencia del método de conservación de las proteínas aisladas (liofilización, congelación) y de las condiciones de procesado seleccionadas sobre el comportamiento reológico y la microestructura de dichas emulsiones. Se han preparado emulsiones aceite en agua (con un contenido del 70% en peso de aceite) estabilizadas con proteínas de atún. La concentración de emulsionante usada ha sido 0,50% en peso. El comportamiento reológico de estas emulsiones no depende significativamente del método de conservación de la proteína empleado. Por otra parte, un aumento de la velocidad de agitación durante el proceso de manufactura de la emulsión da lugar a una disminución continua del tamaño medio de gota y a un aumento de las funciones viscoelásticas dinámicas, menos significativo a medida que aumenta dicha velocidad de agitación. | This work is focused on the development of o/w salad dressing-type emulsions stabilized by tuna proteins. The influence of protein conservation methods after the extraction process (freezing or liofilization) on the rheological properties and microstructure of these emulsions was analyzed. Processing variables during emulsification were also evaluated. Stable emulsions with adequate rheological and microstructural characteristics were prepared using 70% oil and 0.50% tuna proteins. From the experimental results obtained, we may conclude that emulsion rheological properties are not significantly affected by the protein conservation method selected. On the contrary, an increase in homogenization speed favours an increase in the values of the linear viscoelastic functions. Less significant is the fact that as agitation speed increases further, mean droplet size steadily decreases.
Показать больше [+] Меньше [-]Performance of carassius auratus with different food strategies in water recirculation system | Desempenho de carassius auratus com diferentes estratégias alimentares em sistema de recirculação de água Полный текст
2010
Moreira, R. L. | Da Costa, J. M. | Teixeira, E. G. | Moreira, A. G. L. | De Moura, P. S. | Rocha, R. S. | Vieira, R. H. S. F.
The efficiency of a recirculation system for the cultivation of C. auratus, fed with natural and artificial diets was evaluated. The experiment consisted of four treatments with four replicates. The first two treatments used recirculation system and the last two static system. In the first and fourth treatment, animals were fed with brine shrimp biomass (50% CP), while in the second and third treatments a commercial flake ration (42% CP) was used. At the end of cultivation (60 days), water samples were taken from all experimental units and subjected to standard plate count for determining the density of mesophilic bacteria. Final weight (g), final length (cm), specific growth rate (% day -1) and weight gain (%) were significantly different (p | A eficiência de um sistema de recirculação para o cultivo de C. auratus, alimentados com dieta natural e artificial foi avaliada. O experimento consistiu de quatro tratamentos com quatro repetições. Os dois primeiros tratamentos utilizaram sistemas de recirculação e os dois últimos sistemas estáticos. No primeiro e quarto tratamento, os animais foram alimentados com biomassa de artêmia (PB 50%), enquanto nos tratamentos dois e três, com ração comercial em flocos (42% PB). Ao final do cultivo (60 dias), amostras de água foram coletadas em todas as unidades experimentais e submetidos a contagem padrão em placas para determinação da densidade de bactérias mesófilas. O peso final (g), com-primento final (cm), taxa de crescimento específico (% dia-1) e ganho de peso (%) foram signifi-cativamente diferentes (p
Показать больше [+] Меньше [-]Water impacts of food patterns : sustainable diets and food waste water footprints Полный текст
2018
Blas Morente, Alejandro | Garrido Colmenero, Alberto | Willaarts, Barbara
Global food demand is increasing and changing rapidly as a result of multiple drivers as population growth or urban dietary shifts. Managing food consumption (people’s eating habits) might deliver important co-benefits from a water perspective. Many recent studies have addressed the relationship between diet habits and associated water impacts. The goal of this study is to assess and compare the water footprint (WF) of two recommended diets (Mediterranean and American) in Spain and US. Moreover also focuses on assessing the WF of the food consumption and its associated food waste in Spanish households during one year. Our results show that the American diet has a 29% higher WF, regardless of products' origin. Food consumption and waste WFs in Spain are 3,302 and 131 litres/person day respectively. A shift back to a Mediterranean diet, in which fruits, fish and vegetables account for a larger share of the food intake, would deliver great water savings.
Показать больше [+] Меньше [-][Food water activity: measurement methods]
1992
Gomez Diaz, R. (Cordoba Univ. (Spain). Facultad de Veterinaria)
Se han revisado diversos metodos de determinacion de la actividad del agua. Los metodos pueden dividirse en aquellos que requieren el uso de instrumentos comunes de laboratorio y en aquellos que necesitan para su determinacion aparatos especiales. La principal ventaja de los que necesitan aparatos especiales es que la actividad del agua puede determinarse mas rapidamente
Показать больше [+] Меньше [-]Water footprint of food quality schemes Полный текст
2021
Donati, Michele | Torok, A | Gauvrit, Lisa | Arfini, Filippo | Gil Roig, José María | Universitat Politècnica de Catalunya. Departament d'Enginyeria Agroalimentària i Biotecnologia | Universitat Politècnica de Catalunya. CREDA - Centre de Recerca en Economia i Desenvolupament Agroalimentari
Water Footprint (WF, henceforth) is an indicator of water consumption and has taken ground to assess the impact of agricultural production processes over freshwater. The focus of this study was contrasting non-conventional, certified products with identical products obtained through conventional production schemes (REF, henceforth) using WF as a measure of their pressure on water resources. The aim was to the show whether products that are certified as Food Quality Schemes (FQS, henceforth) could also incorporate the lower impact on water among their quality features. To perform this comparison, we analysed 23 products selected among Organic, PDO and PGI as FQS, and their conventional counterparts. By restricting the domain of analysis to the on-farm phase of the production chain, we obtained that that no significant differences emerged between the FQS and REF products. However, if the impact is measured per unit area rather than per unit product, FQS showed a significant reduction in water demand. | Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables | Postprint (published version)
Показать больше [+] Меньше [-]Agua, agricultura y alimentación Полный текст
2024
Melgarejo, Joaquín | López-Ortiz, María Inmaculada | Fernández-Aracil, Patricia | Universidad de Alicante. Instituto Universitario del Agua y las Ciencias Ambientales
Reflections on food security under water scarcity Полный текст
2011
Fereres Castiel, Elías | Orgaz Rosua, Francisco | González-Dugo, Victoria
Forecasts on population growth and economic development indicate that there will be substantial increases in food demand for the forthcoming decades. We focus here on the water requirements of food production, on the issue of whether there would be enough water to produce sufficient food in the future, and we offer options to face this challenge based on recent trends observed in some agricultural systems. Given the competition for water faced by the agricultural sector, and the uncertainties associated with climate change, improving the efficiency of water use in both rain-fed and irrigated systems is the main avenue to face the challenge. In rain-fed agriculture, managing the risk associated with rainfall variability is a promising option to increase productivity. In irrigated systems, a case study on the improvements in water productivity in Andalusia, Spain, is used to illustrate some of the opportunities to make progress. Progress in reducing irrigation water use in recent decades has been substantial, but decreasing the consumptive use of crops is a much more difficult challenge. The need for more research and technology transfer on improving water-limited crop production is highlighted, and emphasis is placed on interdisciplinary approaches to gain the insight needed to achieve new breakthroughs that would help in tackling this complex problem. © 2011 The Author. | The support of a Consolider-Rideco grant CSD2006-0067 from the Ministry of Education and Science of Spain is gratefully acknowledged. | Peer Reviewed
Показать больше [+] Меньше [-]Water availability and food security challenges in Egypt
2005
Hamza, W.,United Arab Emirates University, Al-Ain (United Arab Emirates). Biology Dept. Fac. of Science)Mason, S.
In Egypt, in order to meet the increased food needs, two basic strategies are possible: importing food or growing more food. Egypt imports about 236 m3 water per capita per year in the form of food. Different agriculture projects were established with the aim to enlarge the cultivated area and to guarantee sufficient production of the main crops. Based on the concept of re-use and efficiency increase, it is expected that the use of scientific knowledge, international experience and cooperation as well as advanced management tools should help in the sustainable planning of the future economy. Thus on the national level, re-use and efficient water utilization have the highest priority. According to Egyptian estimates, an additional 20.9 km3year-1 could be made available through recycling water, by changing irrigation techniques and adopting water efficient crops and cropping patterns. This is equal to 30 percent of the water that is used at present.
Показать больше [+] Меньше [-]Trends in the water-energy-food nexus research Полный текст
2024
Rhouma, Ali | El Jeitany, Jerome | Mohtar, Rabi | Gil Roig, José María | Universitat Politècnica de Catalunya. Doctorat en Sostenibilitat | Universitat Politècnica de Catalunya. Departament d'Enginyeria Agroalimentària i Biotecnologia | Universitat Politècnica de Catalunya. CREDA-UPC-IRTA - Centre de Recerca en Economia i Desenvolupament Agroalimentari UPC-IRTA
This paper aims to analyze the scientific evolution and research trends concerning the water–energy–food (WEF) nexus, as well as its development within scientific databases. To achieve this, a bibliometric analysis has been conducted using publications sourced from Scopus and Web of science databases. This study examined key aspects such as primary journals, prominent authors, affiliated institutions, countries of origin, subject areas, and notable keywords. Furthermore, there is a dedicated section that delves into research and innovation gaps within publications related to the WEF nexus. Results reveal that research on the WEF nexus has experienced exponential growth over the past decade, with the majority of publications emerging between 2017 and 2023. The United States leads in this field, with engineering and environmental science being the predominant research categories, with Spain and Italy being the prominent countries in Europe. The WEF nexus concept in the agriculture sector is notably underdeveloped, particularly in its ties with the Sustainable Development Goals and the science–policy–society interface. The study stresses the importance of integrating health considerations into the WEF Nexus to understand the interconnections and their implications on public health, thereby enriching the Nexus approach with a critical dimension of human well-being. This situation underscores the urgent need to create a nexus community that bridges science and practice, and to incorporate this specialized discipline into university curricula. | Peer Reviewed | Postprint (published version)
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