960 research outputs found

    Influence of Partial Soil Wetting on Water Relation Parameters of the Olive Tree

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    A drip versus pond irrigation experiment was carried out with 30-year-old ‘Manzanilla’ olive trees planted at 7 m 5 m in an orchard in Southwest Spain. At the end of the dry season of 1998, we chose two dry-land trees, D1 and D2, and two drip-irrigated trees, I1 and I2. During the experiments, the D1 and I1 trees were pond-irrigated, increasing the soil water content to around field capacity in the whole rootzone. The D2 and I2 trees were drip-irrigated, remaining part of the rootzone in drying soil. The results showed that the ratio between the transpiration of the pond-irrigated D1 tree and that of the drip-irrigated D2 tree (D1/D2 Ep) increased from an average of 0.88 before irrigation to 1.22 fourteen days after the first water supply. For the I trees, I1/I2 Ep varied from 0.76 to 1.02 nine days after the I1 tree was pond-irrigated for the first time. Transpiration, therefore, was restricted when using a drip irrigation system which, despite supplying enough water to cover the calculated crop demand, affected a part of the rootzone only. During the drip versus pond irrigation experiment, the recovery of leaf water potential, stomatal conductance and photosynthesis rate was greater and quicker in the pond-irrigated than in the drip-irrigated trees.– Influence de l’irrigation partielle du sol sur les paramètres des relations hydriques de l’olivier. Une comparaison de l’irrigation goutte à goutte avec l’irrigation en cuvette a été conduite sur oliviers ‘Manzanilla’ âgés de 30 ans plantés à 7 m 5 m dans un verger du sud-ouest de l’Espagne. À la fin de la saison sèche de 1998, nous avons choisi deux arbres sur sol sec, D1 et D2, et deux arbres sur sol irrigué au goutte à goutte, I1 et I2. Durant les expériences, les arbres D1 et I1 ont été irrigués en cuvette, en augmentant la teneur en eau du sol jusqu’à la capacité au champ dans toute la zone racinaire. Les arbres D2 et I2 ont été irrigués au goutte à goutte, laissant une partie de la zone racinaire dans un sol se desséchant. Les résultats ont montré que le quotient entre la transpiration de l’arbre D1 irrigué en cuvette et celle de l’arbre D2 irrigué au goutte à goutte (D1/D2 Ep) a augmenté à partir d’une moyenne de 0,88 avant irrigation jusqu’à 1,22 quatorze jours après le premier apport d’eau. Pour les arbres I, I1/I2 Ep a varié entre 0,76 et 1,02 neuf jours après que l’arbre I1 ait été irrigué en cuvette pour la première fois. Par conséquent, la transpiration était réduite quand on utilisait un système d’irrigation au goutte à goutte qui, malgré l’apport d’eau suffisant pour couvrir les besoins potentiels des cultures, a affecté seulement une partie de la zone racinaire. Durant cette comparaison de l’irrigation goutte à goutte et de l’irrigation en cuvette, la récupération de la teneur en eau des feuilles, de la conductance stomatique et du taux de photosynthèse était supérieure et plus rapide pour les arbres irrigués en cuvette que pour ceux irrigués au goutte à goutte

    Measure of the mining image

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    AbstractMining is a very important activity for economic and social development, but traditionally research has centered on its technical and operative aspects, instead of studying the image transmitted to the rest of society. This has originated diverse problems, fundamentally due to the information which the population receives via the mass media and which sometimes creates a current of opinion contrary to the development of this extraction activity. In order to resolve the mining communication problems it is necessary to develop a measure of the mining image based on a reliable and valid scale. This is a useful tool in developing a procedure to connect the society with other mining stakeholders and to analyze whether the real image of mining activity is similar to the image transmitted and perceived by society, since the news about the mining industry usually are focused on extreme situations or catastrophes that monopolize the information in the media. In this study a field research based on an attributes scale is developed, with the aim of measuring the mining image. The surveys were carried out in a mining area, where people have direct and real information about the mining industry and its consequences on society, environment and economy

    Métodos de estimación de la racha máxima mediante modelos de alta resolución

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    Ponencia presentada en: VII Congreso de la Asociación Española de Climatología: clima, ciudad y ecosistemas, celebrado en Madrid entre el 24 y 26 de noviembre de 2010.[ES]La delimitación precisa de zonas en las que se ha producido una Tempestad Ciclónica Atípica presenta considerables dificultades en nuestro país, debido a la escasez de observaciones de viento y a la complejidad de la orografía. Tal y como está reglamentado, uno de los fenómenos que definen dichas zonas es la aparición de rachas que superen el umbral de los 135 km/h. Con el propósito de conseguir una estimación rápida de la racha máxima en tres segundos, intentado abarcar el mayor número de situaciones de viento extremo, se han desarrollado tres métodos basados en los cálculos obtenidos a través del modelo de flujo lineal LINCOM y de técnicas estadísticas que dan como resultado una estimación de campos de viento extremos y valores puntuales de racha máxima. Esta modelización se incluye dentro de un conocido software llamado WAsP Engineering, cuyo principal ámbito de aplicación se encuentra dentro del sector de la energía eólica. El primero de los métodos calcula directamente el valor de la racha máxima a lo largo de un dominio de unas decenas de kilómetros, utilizando como entrada los valores de racha máxima registrados en las estaciones incluidas en dicho dominio. Los otros dos métodos utilizan unas climatologías basadas en distribuciones de Gumbel calculadas a partir de un registro largo, como mínimo siete años, de valores de racha máxima. Para comprobar la efectividad de los tres métodos se ha realizado una serie de validaciones, utilizando los datos disponibles en el Banco de Datos de Climatología de la AEMet, y seleccionado situaciones de viento extremo registradas en diferentes ámbitos del territorio peninsular.[EN]The precise delimitation of areas where there has been an Atypical Cyclonic Storms (TCA) is a considerably difficult in our country due to the deficiency of wind observations and the complexity of the terrain. According to the Extraordinary Risk Regulation, one of the phenomena that define these areas is the occurrence of gusts exceeding the threshold of 135 km/h. In order to get a quick estimate of the maximum gust in three seconds, cover as many situations of extreme wind, three methods have been developed based on calculations obtained from the linear flow model LINCOM and statistical techniques, obtaining as results an estimation of wind fields and extreme point of maximum gust values. This modelling is included in well known software called WAsP Engineering, whose main application is the wind energy sector. The first of those methods calculates the value of the maximum gust over a domain of a few tens of kilometres, using as input the values of maximum gust recorded at the stations included in that domain. The other two methods use some Climates based on Gumbel distributions calculated from a long record, at least seven years, of maximum gust values. It’ll show some examples of the application of these techniques and its verification against observed data

    Dealing with Fixable and Non-fixable Properties in Service Matchmaking

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    In the context of service discovery, matchmakers check the compliance of service-level objectives from providers and consumers. The problem of bounded uncertainty arises if some property is non-fixable. In this case, the provider is not able to control the value it takes at runtime, so the eventual consumer must not have the choice to select a value and fix it, but only knowing the guaranteed range of values it may take. To the best of our knowledge, there does not exist any approach which deals with this scenario. Most matchmakers work as if all properties were fixable, and a few have assumed the contrary. In either case, the accuracy of their results is likely to be in question since there may be involved both fixable and non-fixable properties at the same time, and there may also exist dependencies between them. In order to improve the accuracy, we present a holistic approach to matchmaking under bounded uncertainty and propose constraint programming as our choice to deal with it, so that matchmaking is transformed into a quantified constraint satisfaction problem.Comisión Interministerial de Ciencia y Tecnología TIN2006-00472Comisión Interministerial de Ciencia y Tecnología TIN2009- 07366Junta de Andalucía TIC-253

    Automatic Generation of Purchasing Plans for Cloud Services

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    The myriad of cloud service providers, as well as their overwhelming variety of configuration and purchasing options, result in a highly complex purchasing scenario. Furthermore, users may specify their needs for cloud services provisioning with a certain scheduling restrictions. There is a need for an automatic support for obtaining an appropriate purchasing plan, which takes into account both service configurations and scheduling needs, while allowing the comparison among different providers and their various offerings. In this work, we present an automatic purchasing plan generator, which analyzes cloud service offerings from several providers to obtain an optimized purchasing plan according to user needs. From the obtained purchasing plan, our solution can provide the corresponding charge plan, possibly including discounts, which serves the purpose of comparing offerings to get the best option.Ministerio de Economía y Competitividad BELI (TIN2015-70560-R)Junta de Andalucía P12--TIC--1867Junta de Andalucía P10-TIC-590

    Implementing Associations among Classes in an Environment of Active Databases

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    The association is a native concept from relational databases, one that has been adapted to object oriented (OO) modelling. It is an interesting operator used to describe links among objects of a system, commonly included in the most popular diagram-based OO methodologies. However, those methodologies sometimes present a lack of formality that may undermine its use. In this paper we formalize the semantics of associations. Firstly, we will describe an OO model based on different kinds of constraints. Some of them will be especially useful for describing the semantics of associations. Finally, we will present some remarks about implementation by means of triggers, a new feature incorporated in databases to specify an inner active behavior.Comisión Interministerial de Ciencia y Tecnología TIC97-0593-C05-0

    Physiological and genetic response of olive leaves to water stress and recovery: implications of mesophyll conductance and genetic expression of aquaporins and carbonic anhydrase

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    8 páginas, 2 figuras, 18 referencias.-- XXVIII International Horticultural Congress on Science and Horticulture for People (IHC2010): International Symposium on CLIMWATER 2010: Horticultural Use of Water in a Changing Climate. Lisboa, Portugal.Drought is considered to be the main environmental factor limiting photo-synthesis (AN) and, consequently, plant growth and yield worldwide. During photosynthesis, the pathway of CO2 from the atmosphere to the site of carboxylation in the chloroplast stroma has two main components: stomatal (gs) and mesophyll (gm) conductances. Both are finite and dynamic, responding to many abiotic factors, therefore reducing CO2 concentration. However, little is known about gm regulation in the short term, where a possible role of aquaporins (AQP) and carbonic anhydrase (CA) has been proposed. Five-year-old olive trees growing in 50 L pots were used to evaluate the acclimation and recovery of AN to drought and subsequent re-watering. Control trees were well-irrigated, while in stressed trees irrigation was withheld for 13 days and then resumed. We made a simultaneous analysis of the genetic expression of two AQP, OePIP1.1 and OePIP2.1, and of CA, on the one hand, and leaf water status, leaf gas exchange and shoot hydraulic conductivity on the other. This is the first time that genetic expression in olive is related to main physiological variables. Two days after withholding irrigation (a.w.i.), the gs and gm values in Stress tress were lower than in Control trees. This limited photosynthesis. Leaf water status decreased from day 4 a.w.i. Midday leaf water potential dropped from -1.2 on the day before withholding irrigation to -6.0 MPa on day 9 a.w.i. CA expression decreased during drought and there was a peak on OePIP1.1 expression on day 4 a.w.i. Leaf water status recovered in ca. 36 h after resuming irrigation. Both gm and AN did not fully recover until 46 days after rewatering. Stomatal conductance, however, did not recover in that period, probably because of an irreversible loss of shoot hydraulic conductivity. Both OePIP1.1 and OePIP2.1 peaked 36 h after rewatering. We found significant correlations between gm and both OePIP2.1 and CA expression.This work was partly supported by grants for projects AGL2005-00220/AGR and AGL-2009-11310.Peer Reviewe
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