966 resultados para exploding in oil layers
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Vertical distribution of common zooplankton species is examined on the base of two series of layer-by-layer net catches down to depth of 3400 m. Differences between the series are significant for most species only near the surface, whereas in deeper layers character of distribution remains the same. Great depths in the Sea of Japan are populated most actively by species performing intensive daily migrations, and less actively by species continuously confined to a definite depth range. Different character of nutrition of the animals apparently determines extent of utilization of deep layers, which are usual for the species.
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The "CoMSBlack92" dataset is based on samples collected in the summer of 1992 along the Bulgarian coast including coastal and open sea areas. The whole dataset is composed of 79 samples (28 stations) with data of zooplankton species composition, abundance and biomass. Sampling for zooplankton was performed from bottom up to the surface at standard depths depending on water column stratification and the thermocline depth. Zooplankton samples were collected with vertical closing Juday net,diameter - 36cm, mesh size 150 ?m. Tows were performed from surface down to bottom meters depths in discrete layers. Samples were preserved by a 4% formaldehyde sea water buffered solution. Sampling volume was estimated by multiplying the mouth area with the wire length. Sampling volume was estimated by multiplying the mouth area with the wire length. The collected material was analysed using the method of Domov (1959). Samples were brought to volume of 25-30 ml depending upon zooplankton density and mixed intensively until all organisms were distributed randomly in the sample volume. After that 5 ml of sample was taken and poured in the counting chamber which is a rectangle form for taxomomic identification and count. Large (> 1 mm body length) and not abundant species were calculated in whole sample. Counting and measuring of organisms were made in the Dimov chamber under the stereomicroscope to the lowest taxon possible. Taxonomic identification was done at the Institute of Oceanology by Asen Konsulov using the relevant taxonomic literature (Mordukhay-Boltovskoy, F.D. (Ed.). 1968, 1969,1972 ). The biomass was estimated as wet weight by Petipa, 1959 (based on species specific wet weight). Wet weight values were transformed to dry weight using the equation DW=0.16*WW as suggested by Vinogradov & Shushkina, 1987. Copepods and Cladoceras were identified and enumerated; the other mesozooplankters were identified and enumerated at higher taxonomic level (commonly named as mesozooplankton groups). Large (> 1 mm body length) and not abundant species were calculated in whole sample. The biomass was estimated as wet weight by Petipa, 1959 ussing standard average weight of each species in mg/m**3.
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The "Hydroblack91" dataset is based on samples collected in the summer of 1991 and covers part of North-Western in front of Romanian coast and Western Black Sea (Bulgarian coasts) (between 43°30' - 42°10' N latitude and 28°40'- 31°45' E longitude). Mesozooplankton sampling was undertaken at 20 stations. The whole dataset is composed of 72 samples with data of zooplankton species composition, abundance and biomass. Samples were collected in discrete layers 0-10, 0-20, 0-50, 10-25, 25-50, 50-100 and from bottom up to the surface at depths depending on water column stratification and the thermocline depth. Zooplankton samples were collected with vertical closing Juday net,diameter - 36cm, mesh size 150 µm. Tows were performed from surface down to bottom meters depths in discrete layers. Samples were preserved by a 4% formaldehyde sea water buffered solution. Sampling volume was estimated by multiplying the mouth area with the wire length. Mesozooplankton abundance: The collected materia was analysed using the method of Domov (1959). Samples were brought to volume of 25-30 ml depending upon zooplankton density and mixed intensively until all organisms were distributed randomly in the sample volume. After that 5 ml of sample was taken and poured in the counting chamber which is a rectangle form for taxomomic identification and count. Large (> 1 mm body length) and not abundant species were calculated in whole sample. Counting and measuring of organisms were made in the Dimov chamber under the stereomicroscope to the lowest taxon possible. Taxonomic identification was done at the Institute of Oceanology by Asen Konsulov using the relevant taxonomic literature (Mordukhay-Boltovskoy, F.D. (Ed.). 1968, 1969,1972). The biomass was estimated as wet weight by Petipa, 1959 (based on species specific wet weight). Wet weight values were transformed to dry weight using the equation DW=0.16*WW as suggested by Vinogradov & Shushkina, 1987. Taxon-specific abundance: The collected material was analysed using the method of Domov (1959). Samples were brought to volume of 25-30 ml depending upon zooplankton density and mixed intensively until all organisms were distributed randomly in the sample volume. After that 5 ml of sample was taken and poured in the counting chamber which is a rectangle form for taxomomic identification and count. Copepods and Cladoceras were identified and enumerated; the other mesozooplankters were identified and enumerated at higher taxonomic level (commonly named as mesozooplankton groups). Large (> 1 mm body length) and not abundant species were calculated in whole sample. Counting and measuring of organisms were made in the Dimov chamber under the stereomicroscope to the lowest taxon possible. Taxonomic identification was done at the Institute of Oceanology by Asen Konsulov using the relevant taxonomic literature (Mordukhay-Boltovskoy, F.D. (Ed.). 1968, 1969,1972). The biomass was estimated as wet weight by Petipa, 1959 ussing standard average weight of each species in mg/m3. WW were converted to DW by equation DW=0.16*WW (Vinogradov ME, Sushkina EA, 1987).
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Microbial mats develop in a wide range of aquatic habitats, such as geothermal hot springs, hypersaline ponds, marine cold seeps or hydrothermal vents. The Nakabusa hot spring is located in the Nagano Prefecture, Japan (36.3875N, 137.75E), dense olive-green microbial mats develop in regions where the slightly alkaline, sulfidic effluent has cooled to 65°C. The microbial community of such mats was analyzed by focusing on the diversity, as well as the in situ distribution and function of bacteria involved in sulfur cycling. Microbial mat samples were kept in sterile plastic tubes (for molecular analysis) or glass bottles completely filled with hot spring water to avoid oxidation. Samples were transferred to the laboratory on ice and used for physiological experiments within 8h. Quantification of cell biovolumes was carried out based on images of mat sections hybridized with Sulfurihydrogenibium- and Chloroflexi-specific probes, and stained with DAPI. In situ hybridizations (CARD-FISH) of thin matsections showed a heterogeneous vertical distribution of Sulfurihydrogenibium and Chloroflexus. Sulfurihydrogenibium dominated near the mat surface (50% of the total mat biovolume), while Chloroflexus dominated in deeper layers (up to 64% of the total mat biovolume).
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Introduction: During the period from the latter half of the 1980s until just before the Asian currency crisis in 1997, Indonesia’s economic development had drawn expectations and attention from various quarters, along with Malaysia and Thailand within the same Association of Southeast Asian Nations (ASEAN). In fact, the 1993 report by the World Bank, entitled “East Asian Miracle: Economic Growth and Public Policy,” recognized Indonesia as one of the East Asian economies with the strong economic performance, i.e. sustained economic growth (World Bank [1993]). And it was the manufacturing industry that had been the driving force behind Indonesia’s economic growth during that period. Since the 1997 outbreak of the Asian currency crisis, however, the manufacturing sector in Indonesia has been mired in a situation that rules out the kind of bright prospects it had emanated previously. The Indonesian economy is still in the developing stage, and in accordance with the history of industrial structural changes in other countries, Indonesia’s manufacturing industry can still be expected to serve as the engine of the country’s economic development. But is it really possible in an environment where economic liberalization and globalization are forging ahead? And, what sort of problems have to be dealt with to make it possible? To answer these questions, it is necessary to know the current conditions of Indonesia’s manufacturing sector, and to do that, it becomes important to think back on the history of the country’s industrialization. Thus, this paper is intended to retrace and unlock the track of Indonesia’s industrialization up until the establishment of the manufacturing sector in its present form, with the ultimate goal being to give answers to the above-mentioned questions. Subject to an analysis in this paper is the period from the installment of President Soeharto’s administration onward when industrialization of the modern industrial sector2 moved into high gear. The composition of this paper is outlined below. Section 1 first shows why it is important to examine import substitution and export orientation, both of which are used as the measures of the analysis in this paper, in tracking the history of the industrialization, and then discuss indicators of import substitution and export orientation as well as statistical data and resources needed to develop those indicators. Section 2 clarifies the status of the manufacturing industry among all industries by looking at the composition ratio of the manufacturing industry in terms of value added, imports and exports. Section 3 to 5 cover three periods between 1971 and 1995 and make an analysis of import substitution, export orientation and changes in the industrial structure for each period. Section 3 analyzes the period from 1971 through 1985, when Indonesia pursued the import substitution policy amid the oil boom. Section 4 covers the period from 1985 through 1990, when the packages of deregulatory measures were announced successively under structural adjustment policies made necessary by the fall in oil prices. Section 5 examines the period from 1990 through 1995, which saw the alternate shifts between the overheating of the economy by sharply rising investment by both domestic and foreign investors in the wake of the liberalization of investment, trade and financial services, and polices to cool down the economy. Section 6, which covers the 1995-1999 period straddling the economic crisis, is designed for an analysis of the changes in production trends before and after the economic crisis as well as the changes in the industrial structure. Section 7, after summing up the history of Indonesia’s industrialization examined in the previous sections, discusses problems found in respective sectors and attempts to present future prospects for the country’s manufacturing industry.
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International politics affect trade patterns, especially for firms in extractive industries. We construct the firm-level dataset for the U.S. oil-importing companies over 1986-2010 to test whether the state of international relations with the trading partners of the U.S. affect importing behavior of the U.S. firms. To measure "political distance" between the U.S. and her trading partners we use voting records for the UN General Assembly. We find that the U.S. firms, in fact, import significantly less oil from the political opponents of the U.S. Our conjecture is that the decrease in oil imports is mainly driven by large, vertically-integrated U.S. firms that engage in foreign direct investment (FDI) overseas.
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Right development of ROOT SYSTEMS is essential to ensure seedling survival in the initial stages of natural regeneration processes. Soil compaction determines this development both because of its influence on soil Tª & moisture dynamics and for its direct effect on soil mechanical impedance to root growth. All this effects can be assessed as a whole through soil penetration resistance (Soil Strength) measurements. SOIL STRENGTH has been usually evaluated in forest research in connection with severe disturbances derived from heavy machinery works during forest operations. Nevertheless, undisturbed soils are also expected to show different levels of compaction for root development. Organic matter modifies soil structure and so on porosity, compaction and resultant soil resistance to penetration. Its concentration in surface layers is rather related to vegetation cover composition and density. So within forest stands, a relationship is expected to be found between VEGETATION COVER density and compaction measured as resistance to penetration (soil strength)
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Maximum production in hedgerow olive orchards is likely not achieved with maximum evapotranspiration over the long-term. Thus, regulated deficit irrigation (RDI) should be considered as a management option. Four irrigation treatments were evaluated during the summer when olive is most drought resistant. Control (CON) was irrigated to maintain the rootzone close to field capacity. Severe water deficit was applied by irrigating 30% CON from end of fruit drop to end July (DI-J) and from end July until beginning of oil synthesis (DI-A). Less severe water deficit was applied during July and August (DI-JA) by irrigating 50% CON. Flowering, fruiting, abscission, fruit development, fresh and dry weight of fruits, and oil production were evaluated. There were not significant differences in number of buds initiated, number of fruits per inflorescence and fruit drop. Oil production was significantly different between irrigation treatments in all experimental years. CON produced more oil and fruit with higher oil% than DI-A and DI-JA. Oil production of DI-J was not significantly reduced compared to CON and oil% was greater. DI-J was the most effective RDI strategy; with 16% less applied water relative to CON average loss in oil production of 8% was not significantly different to CON. While DI-JA saved most water (27%), oil production was reduced by 15%. Greatest loss in oil production (21%) was observed in DI-A with water saving of 22%.
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We have analyzed by means of Rutherford backscattering spectrometry (RBS) the Ti lattice location and the degree of crystalline lattice recovery in heavily Ti implanted silicon layers subsequently pulsed laser melted (PLM). Theoretical studies have predicted that Ti should occupy interstitial sites in silicon for a metallic-intermediate band (IB) formation. The analysis of Ti lattice location after PLM processes is a crucial point to evaluate the IB formation that can be clarifyied by means of RBS measurements. After PLM, time-of-flight secondary ion mass spectrometry measurements show that the Ti concentration in the layers is well above the theoretical limit for IB formation. RBS measurements have shown a significant improvement of the lattice quality at the highest PLM energy density studied. The RBS channeling spectra reveals clearly that after PLM processes Ti impurities are mostly occupying interstitial lattice sites.
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Esta tesis estudia las similitudes y diferencias entre los flujos turbulentos de pared de tipo externo e interno, en régimen incompresible, y a números de Reynolds moderada¬mente altos. Para ello consideramos tanto simulaciones numéricas como experimentos de capas límites con gradiente de presiones nulo y de flujos de canal, ambos a números de Reynolds en el rango δ+ ~ 500 - 2000. Estos flujos de cortadura son objeto de numerosas investigaciones debido a la gran importancia que tienen tanto a nivel tecnológico como a nivel de física fundamental. No obstante, todavía existen muchos interrogantes sobre aspectos básicos tales como la universalidad de los perfiles medios y de fluctuación de las velocidades o de la presión, tanto en la zona cercana a la pared como en la zona logarítmica, el escalado y el efecto del número de Reynolds, o las diferencias entre los flujos internos y externos en la zona exterior. En éste estudio hemos utilizado simulaciones numéricas ya existentes de canales y capas límites a números de Reynolds δ+ ~ 2000 y δ+ ~ 700, respectivamente. Para poder comparar ambos flujos a igual número de Reynolds hemos realizado una nueva simulación directa de capa límite en el rango δ+ ~ 1000-2000. Los resultados de la misma son presentados y analizados en detalle. Los datos sin postprocesar y las estadísticas ya postprocesadas están públicamente disponibles en nuestro sitio web.162 El análisis de las estadísticas usando un único punto confirma la existencia de perfiles logarítmicos para las fluctuaciones de la velocidad transversal w'2+ y de la presión p'2+ en ambos tipos de flujos, pero no para la velocidad normal v'2+ o la velocidad longitudinal u'2+. Para aceptar o rechazar la existencia de un rango logarítmico en u'2+ se requieren números de Reynolds más altos que los considerados en éste trabajo. Una de las conse¬cuencias más importantes de poseer tales perfiles es que el valor máximo de la intensidad, que se alcanza cerca de la pared, depende explícitamente del número de Reynolds. Esto ha sido confirmado tras analizar un gran número de datos experimentales y numéricos, cor¬roborando que el máximo de u'2+, p/2+, y w'2+ aumenta proporcionalmente con el log(δ+). Por otro lado, éste máximo es más intenso en los flujos externos que en los internos. La máxima diferencia ocurre en torno a y/δ ~ 0.3-0.5, siendo esta altura prácticamente independiente del número de Reynolds considerado. Estas diferencias se originan como consecuencia del carácter intermitente de las capas límites, que es inexistente en los flujos internos. La estructura de las fluctuaciones de velocidad y de presión, junto con la de los esfuer¬zos de Reynolds, se han investigado por medio de correlaciones espaciales tridimensionales considerando dos puntos de medida. Hemos obtenido que el tamaño de las mismas es gen¬eralmente mayor en canales que en capas límites, especialmente en el caso de la correlación longitudinal Cuu en la dirección del flujo. Para esta correlación se demuestra que las es¬tructuras débilmente correladas presentan longitudes de hasta 0(75), en el caso de capas límites, y de hasta 0(185) en el caso de canales. Estas longitudes se obtienen respecti-vamente en la zona logarítmica y en la zona exterior. Las longitudes correspondientes en la dirección transversal son significativamente menores en ambos flujos, 0(5 — 25). La organización espacial de las correlaciones es compatible con la de una pareja de rollos casi paralelos con dimensiones que escalan en unidades exteriores. Esta organización se mantiene al menos hasta y ~ 0.65, altura a la cual las capas límites comienzan a organi¬zarse en rollos transversales. Este comportamiento es sin embargo más débil en canales, pudiéndose observar parcialmente a partir de y ~ 0.85. Para estudiar si estas estructuras están onduladas a lo largo de la dirección transver¬sal, hemos calculado las correlaciones condicionadas a eventos intensos de la velocidad transversal w'. Estas correlaciones revelan que la ondulación de la velocidad longitudinal aumenta conforme nos alejamos de la pared, sugiriendo que las estructuras están más alineadas en la zona cercana a la pared que en la zona lejana a ella. El por qué de esta ondulación se encuentra posiblemente en la configuración a lo largo de diagonales que presenta w'. Estas estructuras no sólo están onduladas, sino que también están inclinadas respecto a la pared con ángulos que dependen de la variable considerada, de la altura, y de el contorno de correlación seleccionado. Por encima de la zona tampón e independien¬temente del número de Reynolds y tipo de flujo, Cuu presenta una inclinación máxima de unos 10°, las correlaciones Cvv y Cm son esencialmente verticales, y Cww está inclinada a unos 35°. Summary This thesis studies the similitudes and differences between external and internal in¬compressible wall-bounded turbulent flows at moderately-high Reynolds numbers. We consider numerical and experimental zero-pressure-gradient boundary layers and chan¬nels in the range of δ+ ~ 500 — 2000. These shear flows are subjects of intensive research because of their technological importance and fundamental physical interest. However, there are still open questions regarding basic aspects such as the universality of the mean and fluctuating velocity and pressure profiles at the near-wall and logarithmic regions, their scaling and the effect of the Reynolds numbers, or the differences between internal and external flows at the outer layer, to name but a few. For this study, we made use of available direct numerical simulations of channel and boundary layers reaching δ+ ~ 2000 and δ+ ~ 700, respectively. To fill the gap in the Reynolds number, a new boundary layer simulation in the range δ+ ~ 1000-2000 is presented and discussed. The original raw data and the post-processed statistics are publicly available on our website.162 The analysis of the one-point statistic confirms the existence of logarithmic profiles for the spanwise w'2+ and pressure p'2+ fluctuations for both type of flows, but not for the wall-normal v'2+ or the streamwise u'2+ velocities. To accept or reject the existence of a logarithmic range in u'2+ requires higher Reynolds numbers than the ones considered in this work. An important consequence of having such profiles is that the maximum value of the intensities, reached near the wall, depends on the Reynolds number. This was confirmed after surveying a wide number of experimental and numerical datasets, corrob¬orating that the maximum of ul2+, p'2+, and w'2+ increases proportionally to log(δ+). On the other hand, that maximum is more intense in external flows than in internal ones, differing the most around y/δ ~ 0.3-0.5, and essentially independent of the Reynolds number. We discuss that those differences are originated as a consequence of the inter¬mittent character of boundary layers that is absent in internal flows. The structure of the velocity and pressure fluctuations, together with those of the Reynolds shear stress, were investigated using three-dimensional two-point spatial correlations. We find that the correlations extend over longer distances in channels than in boundary layers, especially in the case of the streamwise correlation Cuu in the flow direc-tion. For weakly correlated structures, the maximum streamwise length of Cuu is O(78) for boundary layers and O(188) for channels, attained at the logarithmic and outer regions respectively. The corresponding lengths for the transverse velocities and for the pressure are shorter, 0(8 — 28), and of the same order for both flows. The spatial organization of the velocity correlations is shown to be consistent with a pair of quasi-streamwise rollers that scales in outer units. That organization is observed until y ~ 0.68, from which boundary layers start to organize into spanwise rollers. This effect is weaker in channels, and it appears at y ~ 0.88. We present correlations conditioned to intense events of the transversal velocity, w', to study if these structures meander along the spanwise direction. The results indicate that the streamwise velocity streaks increase their meandering proportionally to the distance to the wall, suggesting that the structures are more aligned close to the wall than far from it. The reason behind this meandering is probably due to the characteristic organization along diagonals of w'. These structures not only meander along the spanwise direction, but they are also inclined to the wall at angles that depend on the distance from the wall, on the variable being considered, and on the correlation level used to define them. Above the buffer layer and independent of the Reynolds numbers and type of flow, the maximum inclination of Cuu is about 10°, Cvv and Cpp are roughly vertical, and Cww is inclined by 35°.
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Reducing the gap between water-limited potential yield and actual yield in oil palm production systems through intensification is seen as an important option for sustainably increasing palm oil production. Simulation models can play an important role in quantifying water-limited potential yield, and therefore the scope for intensification, but no oil palm model exists that is both simple enough and at the same time incorporates sufficient plant physiological knowledge to be generally applicable across sites with different growing conditions. The objectives of this study therefore were to develop a model (PALMSIM) that simulates, on a monthly time step, the potential growth of oil palm as determined by solar radiation and to evaluate model performance against measured oil palm yields under optimal water and nutrient management for a range of sites across Indonesia and Malaysia. The maximum observed yield in the field matches the corresponding simulated yield for dry bunch weight with a RMSE of 1.7 Mg ha?1 year?1 against an observed yield of 18.8 Mg ha?1. Sensitivity analysis showed that PALMSIM is robust: simulated changes in yield caused by modifying the parameters by 10% are comparable to other tree crop model evaluations. While we acknowledge that, depending on the soils and climatic environment, yields may be often water limited, we suggest a relatively simple physiological approach to simulate potential yield, which can be usefully applied to high rainfall environments and is considered as a first step in developing an oil palm model that also simulates water-limited potential yield. To illustrate the application possibil- ities of the model, PALMSIM was used to create a potential yield map for Indonesia and Malaysia by sim- ulating the growth and yield at a resolution of 0.1?. This map of potential yield is considered as a first step towards a decision support tool that can identify potentially productive, but at the moment degraded sites in Indonesia and Malaysia. ?
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In typical liquid-fueled burners the fuel is injected as a high-velocity liquid jet that breaks up to form the spray. The initial heating and vaporization of the liquid fuel rely on the relatively large temperatures of the sourrounding gas, which may include hot combustion products and preheated air. The heat exchange between the liquid and the gas phases is enhanced by droplet dispersion arising from the turbulent motion. Chemical reaction takes place once molecular mixing between the fuel vapor and the oxidizer has occurred in mixing layers separating the spray flow from the hot air stream. Since in most applications the injection velocities are much larger than the premixed-flame propagation velocity, combustion stabilization relies on autoignition of the fuel-oxygen mixture, with the combustion stand-off distance being controlled by the interaction of turbulent transport, droplet heating and vaporization, and gas-phase chemical reactions. In this study, conditions are identified under which analyses of laminar flamelets canshed light on aspects of turbulent spray ignition. This study extends earlier fundamental work by Liñan & Crespo (1976) on ignition in gaseous mixing layers to ignition of sprays. Studies of laminar mixing layers have been found to be instrumental in developing un-derstanding of turbulent combustion (Peters 2000), including the ignition of turbulent gaseous diffusion flames (Mastorakos 2009). For the spray problem at hand, the configuration selected, shown in Figure 1, involves a coflow mixing layer formed between a stream of hot air moving at velocity UA and a monodisperse spray moving at velocity USUA. The boundary-layer approximation will be used below to describe the resulting sl ender flow, which exhibits different igniting behaviors depending on the characteristics of t he fuel. In this approximation, consideration of the case U A = U S enables laminar ignition distances to be related to ignition times of unstrained spray flamelets, thereby pro viding quantitative information of direct applicability in regions of low scala r dissipation-rate in turbulent reactive flows (see the discussion in pp. 181–186 of Peters (2000)) . This report is organized as follows. Effects of droplet dispersion dynamics on ignition of sprays in turbulent mixing layers are discussed in Section 2. The formulation f or ignition in laminar mixing layers is outlined in Sections 3 and 4. The results are presented in Section 5. In Section 6, the mixture-fraction field and associated scalar dissipat ion rates for spray ignition are discussed. Finally, some brief conclusions are drawn in Section 7.
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En las últimas dos décadas, los productores han plantado olivares en seto para lograr la mecanización de la poda y en especial de la cosecha, reducir los costes de mano de obra y permitir intervenciones de manejo rápidas y oportunas. Los olivares se desarrollaron en ausencia del conocimiento científico, sobre el diseño óptimo de la estructura de la copa, necesario para incrementar la producción y calidad del aceite. En contraste, con los árboles muy espaciados y distribuidos uniformemente de las plantaciones tradicionales, en el olivar en seto hay una marcada variabilidad espacial y temporal de la radiación disponible en función del diseño de la plantación. Así, conocer la respuesta fisiológica y productiva del olivo a la radiación resulta fundamental en el olivar en seto. La orientación de las filas y el ancho de calle son aspectos que se deciden en el diseño de las plantaciones en seto. Ambos aspectos modifican la radiación interceptada por la canopia y, por lo tanto, pueden incidir en la productividad y calidad del aceite. Una vez realizada la plantación no pueden ser modificados, y así las ventajas o desventajas permanecerán fijas durante toda la vida productiva del olivar. A pesar de esto, el impacto de la orientación de las filas y el ancho de calle han recibido poca atención en olivos y en la mayoría de los frutales conducidos en seto. Por todo ello, los objetivos principales de esta tesis fueron, (i) evaluar el efecto de la orientación del seto y del ancho de calle, sobre la productividad y calidad del aceite, (ii) evaluar un modelo que estime la radiación dentro de la canopia. Este modelo permitirá cuantificar las relaciones entre la radiación y los componentes del rendimiento y calidad del aceite de olivares en setos con un amplio rango de estructuras y (iii) conocer la variabilidad en las características de las hojas (morfológicas y fisiológicas) y de los tejidos del fruto (tamaño y composición) en diferentes posiciones de la copa de los setos. Para ello, se dispuso de 3 ensayos de olivar en seto (cv. Arbequina) implantados en 2008 en el municipio de La Puebla de Montalbán, Toledo. La primera cosecha fue en 2010 y a partir del 2012 los setos formaron una copa continua. A partir de ese año, los setos se mantuvieron mediante poda, con similar ancho (~1 m) y altura (~2,5 m), acordes a las dimensiones de la cosechadora vendimiadora. En los años 2012 y 2013 se estudió en profundidad la respuesta de las plantas de estos ensayos. En el ensayo 1, los setos fueron plantados con cuatro orientaciones de filas: N–S, NE–SO, NO–SE y E–O y el mismo ancho de calle (4 m). En los otros dos ensayos, los setos fueron plantados con tres anchos de calle (5,0, 4,0 y 2,5 m), y con filas orientadas N–S (ensayo 2) y E–O (ensayo 3). La respuesta de la orientación de las filas se evaluó a nivel de seto y de estratos del seto (alturas y caras), a través de mediciones del crecimiento de brotes, componentes reproductivos, características y temperatura del fruto, estado hídrico del suelo y de las plantas, fotosíntesis neta de las hojas y contenido de ácidos grasos. Los setos orientados NE–SO (2,7 t/ha) lograron la mayor producción de aceite, que fue significativamente más alta que la de los setos E–O (2,3 t/ha). La producción de aceite de los setos E–O no se diferenció estadísticamente de los setos N–S (2,5 t/ha). Las diferencias productivas entre orientaciones fueron explicadas por el número de frutos en cosecha, a su vez la variación en el número de frutos estuvo asociada al efecto de la orientación de las filas sobre el número de yemas desarrolladas y el porcentaje de inflorescencias fértiles. Las hojas en las caras iluminadas de los setos NE–SO y N–S presentaron mayor tasa fotosintética a la mañana (~10.0 h) que los setos E–O, en el año 2012, pero no en 2013. La orientación de las filas no tuvo un efecto significativo en el contenido de ácidos grasos de los aceites extraídos, esto ocurrió a pesar de variaciones en la temperatura interna de los frutos (3 °C) y de la radiación (40%) entre las distintas caras de los setos. La orientación del seto afectó significativamente al contenido relativo de agua del suelo, donde setos E–O presentaron valores más altos (12%) que setos N–S durante el verano y otoño. Sin embargo, el potencial hídrico de tallo fue similar entre orientaciones. En los ensayos 2 y 3, se evaluó el efecto que produce, a nivel de seto y de estratos (caras y alturas), reducir el ancho de calle de 5,0 a 4,0 y 2,5 m, en un seto orientado N–S y otro E–O, respectivamente. La relación entre altura/ancho de calle libre aumentó 0,6 a 0,8 y 1,6, al reducir 5,0, 4,0 y 2,5 m el ancho de calle, mientras la longitud de seto y el volumen de copa por hectárea incrementó 100% al reducir de 5,0 a 2,5 m, el ancho de calle. En los setos orientados N–S, la producción de aceite por ha acumulada en 4 campañas, incrementó significativamente un 52 %, al reducir de 5,0 a 2,5 m el ancho de calle. Los setos N–S con calle más estrecha (2,5 m) tuvieron un 19% menos frutos que los setos con calle más ancha (5,0 m) y a su vez el 60% de los mismos se localizaron los estratos altos de la canopia de los setos con calles estrecha en comparación al 40% en setos con calle de 5,0 m. En los estratos más bajos de los setos con calles de 2,5m hubo menor crecimiento de los brotes y los frutos tuvieron menor peso seco, contenido de aceite y madurez, que los frutos en los estratos bajos de los setos a 5,0 m. Los componentes del rendimiento y características de los frutos (agua y madurez) fueron similares entre la caras E y O, independientemente del ancho de calle. En los setos orientados E–O, la producción de aceite por ha acumulada en 4 campañas, no respondió significativamente al ancho de calle, debido a una disminución significativa en el número de frutos y producción de aceite por m de seto, al reducir de 5,0 a 2,5 m, el ancho de calle. En los setos orientados E–O, con calles de 5,0 m, los frutos presentaron similar peso seco, contenido de aceite y agua, en las caras S y N, sin embargo, cuando la calle fue reducida a 2,5, los frutos de la cara S fueron más pesado y maduros que en la cara N. Independientemente del ancho de calle y de la orientación del seto, el aceite presentó mayor contenido de ácidos palmitoleico, palmítico, esteárico y linoleico en los frutos del estrato más alto de la canopia disminuyendo hacia la base. En contraste, el contenido de ácido oleico aumentó desde el estrato más alto hacia la base de los setos. Las diferencias en el contenido de ácidos grasos entre la parte alta y baja de los setos, incrementó al reducir el ancho de calle en los setos N–S, pero no en los E-O. En conclusión, en olivares en seto, reducir el ancho de calle permite incrementar la producción de aceite, en setos orientados N–S, pero no en E–O. Un modelo que estima la cantidad y distribución de la radiación en toda la copa del seto, fue utilizado para estimar la radiación interceptada en distintos estratos del seto. El modelo requiere un valor del coeficiente de extinción (k) para estimar la transmisión de radiación a través de la copa, el cual fue obtenido experimentalmente (k=1,2). Utilizando los datos del ensayo 1, un único modelo lineal relacionó el peso seco y el rendimiento graso de setos con la radiación interceptada por los distintos estratos de setos con cuatro orientaciones de filas. La densidad de frutos fue también relacionada con la radiación, pero más débilmente. En los setos orientados N–S, plantados con tres anchos de calles, (ensayo 2) el contenido de ácidos palmitoleico y linoleico del aceite incrementó linealmente con el incremento de la radiación interceptada, mientras el contenido ácido oleico disminuyó linealmente con el incremento de la radiación. El contenido de ácidos grasos del aceite no estuvo relacionado con la radiación interceptada en setos orientados E–O (Ensayo 3). En los setos N–S y E–O, plantados con anchos de calle de 2,5 m, se estudiaron las interacciones entre la radiación y características de las hojas, número de fruto, tamaño y composición de los frutos a nivel de órgano, tejido y células. Independientemente de la orientación del seto, el área y el contenido de clorofila de las hojas incrementaron significativamente en los estratos más bajos de los setos. Mientras, las hojas de los estratos medios del seto presentaron mayor capacidad fotosintética que en los estratos bajos y alto de los setos. Los estratos del seto que interceptaron más radiación produjeron frutos con mayor tamaño y contenido de aceite en el mesocarpo, sin efectos sobre el tamaño y composición del endocarpo. A nivel celular, los frutos expuestos a mayor nivel de radiación desarrollaron en el mesocarpo células de mayor tamaño en comparación a frutos menos expuestos, mientras el número de células no fue afectado. Adicionalmente, el número y tamaño de las células estuvo relacionado con la composición del mesocarpo en términos de aceite, agua y peso seco menos aceite. Esta tesis, contribuye, desde una perspectiva integral del cultivo del olivo, a cuantificar el impacto de la orientación y ancho de calle sobre la producción y calidad del aceite en olivares conducidos en setos. El análisis y discusión de la relación entre la radiación y los componentes del rendimiento y calidad del aceite, puede ayudar a diseñar plantaciones en seto con dimensiones óptimas para la intercepción de la radiación. ABSTRACT In the last two decades, olive hedgerow system has been established by commercial growers to allow continuous mechanized pruning and especially harvest, reduce costs of manual labour and allow more rapid and timely management interventions. The adoption of hedgerow was done in the absence of adequate scientific knowledge of the impact of this orchard structure and associated mechanization on tree response, yield and quality, after centuries in low-density orchards and open-formed trees. The row orientation and width alley are fundamental aspects in the hedgerow design and have been scarcely studied in olive. Both aspects modify the radiation intercepted by the canopy, and consequently the productivity and oil quality, and once defined in orchard planting cannot be changed, so advantages and disadvantages remain fixed for the lifespan of the orchard. The main objectives of this thesis were to (i) evaluate the impact of the row orientation and width alley on productivity and oil quality by the measurements of profile of the determining processes of shoot growth, fruit temperature, yield components and fruit and oil characteristics on opposite sides of olive hedgerows. Additionally, the effect of row orientation on the plant water status was also evaluated; (ii) evaluate a mathematical model for estimating the radiation within the canopy and quantify the relationships between the radiation estimated and yield components and oil quality in olive hedgerows under wide range of structures and; (iii) determine the variability in the characteristics of the leaves (morphological and physiological) and fruit tissues (size and composition) in different positions of the hedgerows canopy. Three plots of olive hedgerows (cv. Arbequina) planted in 2008 in La Puebla de Montalbán, Toledo were evaluated during the 2012 and 2013 seasons. The hedgerows were maintained by lateral pruning and topping with the same width (1 m) and height (2.5 m) compatible with the intended harvester. In a plot (experiment 1), the hedgerows were planted with the same width alley (4 m) and four row orientations: N–S, NE–SW, NW–SE and E–W. Other two plots (Experiments 2 and 3) separated by approximately 100 m were planted with N–S and E–O oriented rows and three alley widths in each orientation: 5.0, 4.0 and 2.5 m. In the exp. 1, maximum fruit yield were achieved by NE–SW and NW–SW (15.7 t/ha). Of these, NE–SW achieved the highest oil yield (2.7 t/ha). There were no differences in fruit or oil yield between N–S (2.5 t oil/ha) and E–W (2.3 t oil/ha) orientations. Fruit number was the most important component to explain these differences, by previous influence on number of bud developed and percentage of fertile inflorescences. Fruit maturity and oil quality on both sides of the hedgerows were not affected by row orientation. This occurred despite significant variations in the internal fruit temperature, which was closely related to the irradiance received by the canopy and the time of day. Additionally, row orientation significantly affected the relative water content of the soil, where E–W oriented hedgerows showed consistently higher values than N–S during summer-autumn season. The stem water potential at midday, however, was similar between orientations, revealing possible lower water consumption of E–W than N–S oriented hedgerows. In the exp. 2, regardless of row orientation, reduction of row spacing from 5.0 to 4.0 and 2.5 m increases the ratio of canopy depth to free alley width (Al/An) from 0.6 to 0.8 and 1.6, respectively, and ads 25 and 100 % more hedgerow length per ha. In N–S oriented hedgerows, oil production per ha increased significantly by 14 and 52 % in 4.0 m and 2.5 m relative to 5.0 m row spacing, the effect being proportionally less than the increase in hedgerow length per ha. Hedgerows spaced 2.5 m with Al/An = 1.6 produced relatively fewer fruits per unit length than did wider spacings and were preferentially distributed in upper layers. Fruits located at the bottom of the canopy were smaller, with lower oil content and were less mature. In E–W oriented hedgerows, oil production per ha did not respond significantly to row spacing, despite the doubling of row length from the 5.0 to the 2.5 m row spacing. The explanation was found in fewer fruit per unit length of hedgerow and smaller oil content at 2.5 m than 5.0 m row spacing, averaged over the experimental period. In E–W hedgerows spaced at 5.0 m with Al/An = 0.6, the vertical profiles of fruit characteristics (mass, oil and water contents, and maturity) were similar between opposing sides, but at 4.0 m (Al/An= 0.8) and 2.5 m (Al/An=1.6) spacings, fruits on the S side were heavier and more mature than on N side. The oil extracted from fruits harvested at different heights of N–S and E–W oriented hedgerows showed higher palmitoleic, palmitic, stearic and linoleic contents at the canopy top decreasing toward base. The oleic content was reverse, increased from top to base. In N–S hedgerows, vertical gradients increased by reducing the alley width, but not in the E–W oriented hedgerows. The simulation of internal canopy irradiance was related in a single relationship (R2 = 0.63) to the vertical profiles of fruit weight and oil content of olive hedgerows with wide range of structures. The density of fruits was also associated with the irradiance but more weakly (R2 = 0.27), and revealed a more complex response involving changes in the vegetative structure by canopy management (topping) and the effect of radiation on the previous sequence that defines the number of fruits. The vertical profiles of oil quality traits were closely associated to canopy irradiance, but only when the N–S oriented hedgerows were considered. The contents of palmitoleic and linoleic acid in the oil increased linearly when intercepted irradiance increased from 9 to 19 mol PAR/m2. In contrast, oleic content decreased linearly in this irradiance range. Additionally, we advanced knowledge regarding the interactions among irradiance and leaf, fruit number, size and composition at organ-, tissue- and cellular- levels. The irradiance received at different positions in the canopy strongly affected the leaf area and chlorophyll content, and mesocarp size and composition (water and oil), without effects on endocarp size and composition. At the cellular level, light-exposed fruit developed larger mesocarp cells than shaded fruits, but cell number was not affected. Our results indicate that cell number and size are related to mesocarp composition in term of oil, water, and dry weight menus oil, although the specific manner in which they interact remains to be determined. This research contributes from an integral perspective of olive growing to quantify the impact of row orientation and width alley on productivity and oil quality in hedgerows systems. The analysis and discussion of the relationships between radiation and yield components and oil quality can help understand the impact of design olive hedgerows in general and in a wide range of environmental conditions.
Availability and uptake of trace elements in a forage rotation under conservation and plough tillage
Resumo:
After 14 years under conventional plough tillage (CT) or conservation minimum tillage (MT), the soil available Al, Fe, Mn, Cu and Zn (0-5, 5-15 and 15-30 cm layers) and their plant uptake were evaluated during two years in a ryegrass-maize forage rotation in NW Spain (t emperate-humid region). The three-way ANOVA showed that trace element concentrations in soil were mainly influenced by sampling date, followed by soil depth and tillage system (35-73 %, 7-58 % and 3- 11 % of variance explained, respectively). Excepting for Fe (CT) and Al (CT and MT), the elemental concentrations decreased with depth, the stratification being stronger under MT. For soil available Al, Fe, Mn and Cu, the concentrations were higher in CT than in MT (5-15 and 15-30 cm layers) or were not affected by tillage system (0-5 cm). In contrast, the available Zn contents were higher in MT than CT at the soil surface and did not differ in deeper layers. The concentration of Al, Fe and Cu in crops were not influenced by tillage system, which explain 22 % of Mn variance in maize (CT > MT in the more humid year) and 18 % of Zn variance in ryegrass (MT > CT in both years). However, in the summer crop (maize) the concentrations of Fe, Mn and Zn tended to be higher in MT than in CT under drought conditions, while the opposite was true in the year without water limitation. Therefore, under the studied conditions of climate, soil, tillage and crop rotation, little influence of tillage system on crop nutritive value would be expected. To minimize the potential deficiency of Zn (maize) and Cu (maize and ryegrass) on crop yields the inclusion of these micro-nutrients in fertilization schedule is reco mmended, as well as liming to alleviate Al toxicity on maize crops.
Resumo:
Laser Shock Processing (LSP) has been demonstrated as an emerging technique for the induction of RS’s fields in subsurface layers of relatively thick specimens. However, the LSP treatment of relatively thin specimens brings, as an additional consequence, the possible bending in a process of laser shock forming. This effect poses a new class of problems regarding the attainment of specified RS’s depth profiles in the mentioned type of sheets, and, what can be more critical, an overall deformation of the treated component. The analysis of the problem of LSP treatment for induction of tentatively through-thickness RS’s fields for fatigue life enhancement in relatively thin sheets in a way compatible with reduced overall workpiece deformation due to spring-back self-equilibration is envisaged in this paper. The coupled theoretical-experimental predictive approach developed by the authors has been applied to the specification of LSP treatments for achievement of RS's fields tentatively able to retard crack propagation on normalized specimens. A convergence between numerical code results and experimental results coming from direct RS's measurement is presented as a first step for the treatment of the normalized specimens under optimized conditions and verification of the crack retardation properties virtually induced.