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Untersuchungen zu einem mit Hedera helix 'Woerner' begrünten, hydroponischen Nutzwandsystem : Evaluierung ertrags- und pflanzenphysiologischer Parameter unter Berücksichtigung der klimatischen Einflüsse zur Modellierung eines intelligenten Wasser- und NährlösungsmanagementsWolter, Adelheid 29 February 2016 (has links) (PDF)
Forschungsgegenstand war ein neuentwickeltes modulares Kassettensystem mit Hedera helix 'Woerner', das im Folgenden als hydroponische Nutzwand bezeichnet wurde. Die Lebensqualität in Ballungsräumen sinkt aufgrund von steigender Verdichtung. Stadtgrün verbessert die Lebensqualität und sorgt für lokale Klima- und Luftverbesserung. Allerdings besteht ein Nutzungskonflikt mit anderen Bebauungsvorhaben. Hier verspricht der Einsatz der hydroponischen Nutzwand ein hohes Potential, da das wandgebundene Fassadenbegrünungssystem weitgehend bodenunabhängig ist.
Es erfolgte eine Studie zur Quantifizierung des Leistungspotenzials. Neben einer detaillierten Beschreibung des Kassettensystems und der Versuchsanlage, die eine nach Norden und eine nach Süden exponierte Nutzwand darstellte, erfolgte die Erstellung einer Wasserbilanz und eines abgeleiteten Bewässerungsplanes. Im Substrat wurden Untersuchungen zum Sauerstoffgehalt durchgeführt. Ebenso war auch die Wirkung auf das Bestandsklima ein wesentliches Kriterium, um das Kassettensystem zu beschreiben. Für die Leistungsabschätzung wurden Wachstumsanalysen zur Beschreibung der Pflanzenproduktion durchgeführt. Für einige Kassettenelemente wurde dabei im Wurzelraum ein Pflanzenstärkungsmittel mit Bacillus subtilis angewendet, mit dem Ziel, eine Wachstumssteigerung zu erreichen. In einem Austrocknungsversuch im Gewächshaus wurde der Effekt verschiedener Konzentrationen des Pflanzenstärkungsmittels auf eine erhöhte Stresstoleranz von Hedera helix 'Woerner' untersucht. Der Wasserhaushalt stellte einen gesonderten Schwerpunkt dar, bei dem zwei Ansätze zur Bewässerungssteuerung verfolgt wurden. Es erfolgte eine Modellierung der Evapotranspiration über Daten aus meteorologischen Messungen und Messungen zur Transpiration der Pflanzen im Bestand. In einem zweiten Ansatz wurden die Möglichkeiten der pflanzenbasierten Sensorik untersucht, wofür ein elektronischer Blattdickensensor zum Einsatz kam.
Die Erkenntnisse aus der Dissertation sollten zeigen, welche Praxistauglichkeit eine hydroponische Nutzwand besitzt und ob sie lokal in der Lage ist, dem Problem sinkender Lebensqualität im städtischen Raum entgegenzuwirken.
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Herbage production as a function of soil moisture stress in a semiarid areaOwtadolajam, Esmail. January 1982 (has links)
Soil water deficits greatly affect forage production. To evaluate the effects of soil moisture stress on forage production, a budgeting model was developed. The soil water budgeting model uses the initial soil water content which can be assumed or calculated. Stress was calculated as a difference between potential evapotranspiration and actual evapotranspiration at a level of - 5 bar. A radiation method was used to calculate the potential evapotranspiration and the soil water budgeting model was used to calculate the actual evapotranspiration. The Soil Conservation Service method was applied to calculate runoff and effective rainfall was calculated by subtraction of runoff from original rainfall and used in the model for calculation of actual evapotranspiration. Calculated stress was correlated to the yield and stepwise multiple regression were used to produce prediction equations. Observed soil water data and yield for calibration and validation of the models were obtained from Santa Rita Forest and Range Experimental Range in southeastern Arizona.
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Échanges d’énergie et d’eau des écosystèmes nordiques dans un contexte de changement climatiquePayette, Fanny 12 1900 (has links)
Le réchauffement climatique affecte fortement les régions nordiques du Canada où le dégel du pergélisol discontinu à sa limite sud est accompagné du mouvement de la limite des arbres vers le nord en zone de pergélisol continu. Ces altérations faites aux paysages de la Taïga des Plaines sont le point de départ de plusieurs rétroactions puisque les changements apportés aux caractéristiques de la surface (au niveau de l’albédo, l’humidité du sol et la rugosité de la surface) vont à leur tour entraîner des modifications biophysiques et éventuellement influencer l’augmentation ou la diminution subséquente des températures et de l’humidité de l’air. Seulement, il y a un nombre important de facteurs d’influence qu’il est difficile de projeter toutes les boucles rétroactives qui surviendront avec les présents changements climatiques en régions nordiques. Dans le but de caractériser les échanges d’eau et d’énergie entre la surface et l’atmosphère de trois sites des Territoires du Nord-Ouest subissant les conséquences de l’augmentation des températures de l’air, la méthode micro-météorologique de covariance des turbulences fut utilisée en 2013 aux sites de Scotty Creek (forêt boréale et tourbière nordique en zone de pergélisol sporadique-discontinu), de Havikpak Creek (forêt boréale nordique en zone de pergélisol continu) et de Trail Valley Creek (toundra arctique en zone de pergélisol continu). En identifiant les procédés biotiques et abiotiques (ex. intensité lumineuse, disponibilité en eau, etc.) d’évapotranspiration aux trois sites, les contrôles par l’eau et l’énergie furent caractérisés et permirent ainsi de projeter une augmentation de la limitation en eau, mais surtout en énergie du site de Trail Valley Creek. La répartition de l’énergie projetée est semblable à celle de Havikpak Creek, avec une augmentation de la proportion du flux de chaleur sensible au détriment de celui latent suite aux modifications des caractéristiques de la surface (albédo, rugosité et humidité du sol). L’augmentation relative du flux d’énergie sensible laisse présager une boucle rétroactive positive de l’augmentation des températures de l’air à ce site. Ensuite, en comparant des données modelées de la hauteur de la couche limite planétaire et des données provenant de profils atmosphériques d’Environnement Canada entre les trois sites, les changements de hauteur de cette couche atmosphérique furent aussi projetés. Trail Valley Creek pourrait connaître une hausse de la hauteur de sa couche limite planétaire avec le temps alors que Scotty Creek connaîtrait une diminution de celle-ci. Ces changements au niveau des couches atmosphériques liés à la répartition des flux d’énergie dans les écosystèmes se répercuteraient alors sur le climat régional de façon difficile à déterminer pour l’instant. Les changements apportés désignent une boucle rétroactive positive des températures de l’air à Trail Valley Creek et l’inverse à Scotty Creek. Les deux axes d’analyse arrivent donc aux mêmes conclusions et soulignent aussi l’importance de l’influence mutuelle entre le climat et les caractéristiques spécifiques des écosystèmes à la surface. / Along the southern margin of permafrost, the boreal forest is underlain by ice-rich and relatively warm permafrost which is converted into permafrost-free peatlands and lake ecosystems due to warmer temperatures and increased thaw rates. At the same time, in the continuous permafrost zone the tree-line of the boreal forest is advancing northward into what is currently Arctic tundra. Both land cover changes in the Taiga Plains ecozone are affecting the magnitude of complex feedback loops, including regional biophysical feedbacks through altered net water vapor and heat exchanges caused by changes in land surface albedo, hydrology and surface roughness. Changes affecting the ecosystems are numerous and it is currently hard to estimate the direction (positive or negative) and magnitude of the resulting biophysical feedbacks. To improve our understanding of implications arising from land cover changes, the energy and water exchanges between surface and atmosphere at three sites in the Northwest Territories, Canada are characterized: Scotty Creek (boreal forest-peatland landscape with sporadic permafrost), Havikpak Creek (boreal forest with continuous permafrost) and Trail Valley Creek (tundra with continuous permafrost). The results of this study are based on measurements of water vapor and heat fluxes obtained with the eddy covariance technique, in addition to supporting ancillary measurements (e.g., net radiation, ground heat flux). For the growing season of 2013, biotic and abiotic controls (ex. light intensity, water availability, etc.) of evapotranspiration at the three sites were identified and analyzed leading to a projected increase in water and energy limitation for Trail Valley Creek. This limitation can be explained by increased energy repartition to sensible heat than to latent heat, following alterations of the land surface as the treeline moves towards the arctic tundra landscape. The relative increase in the sensible heat flux is an indication for an amplified positive feedback of rising air temperature. A comparison of modeled planetary boundary layer heights with Environment Canada atmospheric profiles for the sites leads to the same projection of a positive air temperature feedback. As the treeline moves north, at Trail Valley Creek, an increase of its planetary boundary layer is expected and the opposite phenomenon is expected at Scotty Creek. Albedo, hydrology and surface roughness will be modified, affecting energy partitioning and atmospheric layers which in turn will influence climate. The two methods have led to the same conclusion and highlight the importance of mutual influence between climate and land surface characteristics.
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Hodnocení zátěže životního prostředí v ČR pomocí indikátoru Vodní stopa / Environmental assessment of the Czech Republic based on Water FootprintŽlábková, Jana January 2013 (has links)
This dissertation sets its goal in application of the water footprint indicator, which is a practical and multi-layered indicator of water sources consumption. Of human activities, agriculture presents the most significant demands on water sources consumption. Therefore I have turned my focus to the widely-discussed issue of biofuels production, because the input materials for production of this kind of energy are agricultural crops (in the Czech republic those are: oilseed rape, sugar beet, Indian corn and winter wheat). The calculated results of water footprints of the selected industrial crops (m3 /t) and of water footprints of the heating value units of that crops (m3 /GJ) offer us a concrete notion of energy requirements of water of that chosen industrial crops in the conditions of the Czech republic. Keywords: water footprint indicator, biofuels, oilseed rape, water consumption, biodiesel, bioethanol, evapotranspiration.
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Evaluation of surface energy balance models for mapping evapotranspiration using very high resolution airborne remote sensing dataPaul, George January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / P.V. Vara Prasad / Agriculture is the largest (90%) consumer of all fresh water in the world. The consumptive use of water by vegetation represented by the process evapotranspiration (ET) has a vital role in the dynamics of water, carbon and energy fluxes of the biosphere. Consequently, mapping ET is essential for making water a sustainable resource and also for monitoring ecosystem response to water stress and changing climate. Over the past three decades, numerous thermal remote sensing based ET mapping algorithms were developed and these have brought a significant theoretical and technical advancement in the spatial modeling of ET. Though these algorithms provided a robust, economical, and efficient tool for ET estimations at field and regional scales, yet the uncertainties in flux estimations were large, making evaluation a difficult task. The main objective of this study was to evaluate and improve the performance of widely used remote sensing based energy balance models, namely: the Surface Energy Balance Algorithm for Land (SEBAL), Mapping Evapotranspiration at high Resolution and with Internalized Calibration (METRIC), and Surface Energy Balance System (SEBS). Data used in this study was collected as part of a multi-disciplinary and multi-institutional field campaign BEAREX (Bushland Evapotranspiration and Agricultural Remote Sensing Experiment) that was conducted during 2007 and 2008 summer cropping seasons at the USDA-ARS Conservation and Production Research Laboratory (CPRL) in Bushland, Texas. Seventeen high resolution remote sensing images taken from multispectral sensors onboard aircraft and field measurements of the agro-meteorological variables from the campaign were used for model evaluation and improvement. Overall relative error measured in terms of mean absolute percent difference (MAPD) for instantaneous ET (mm h[superscript]-[superscript]1) were 22.7%, 23.2%, and 12.6% for SEBAL, METRIC, and SEBS, respectively. SEBAL and METRIC performances for irrigated fields representing higher ET with limited or no water stress and complete ground cover surfaces were markedly better than that for dryland fields representing lesser ET and greater soil water deficits with sparser vegetation cover. SEBS algorithm performed equally well for both irrigated and dryland conditions but required accurate air temperature data. Overall, this study provides new insights into the performance of three widely used thermal remote sensing based algorithms for estimating ET and proposed modifications to improve the accuracy of estimated ET for efficient management of water resources.
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Etude du rôle de la végétation dans la création de microclimats urbains : approche combinée de mesures et de modélisations à différentes échelles / Study of vegetation purpose in urban microclimates creation : combined approaches of measures and modellings at different scalesBournez, Elena 19 November 2018 (has links)
Le phénomène d'îlot de chaleur urbain engendre de l'inconfort thermique auprès des habitants. Améliorer le microclimat en zone urbaine est donc l'une des préoccupations des aménageurs. La végétalisation des villes s'avère une solution prometteuse, car l'évapotranspiration des plantes etles ombres portées des arbres ont un impact significatif sur le bilan thermique de l'atmosphère alentour. Un défi majeur aujourd'hui est le développement d'un modèle de simulation microclimatique capable de reproduire les conditions climatiques d'une rue, voire d'un quartier urbain végétalisé, dans l'objectif de proposer un outil d'aide à la décision pour l'aménagement des villes durables. L'objectif de cette thèse est d'étudier comment prendre en compte la végétation et plus particulièrement les arbres, dans un modèle microclimatique 30 afin de simuler le microclimat d'un quartier. Deux modèles, LASER/F et RATP sont appliqués à l'échelle d'un arbre et d'un parc urbain pour mener à bien cette étude. / The urban heat island phenomenon causes thermal discomfort to residents. lmproving the microclimate in urban areas is therefore one of the concerns of urban plan ners. The greening of cities (with lawns, trees, green roofs, etc.) is a promising solution, as the transpiration of plants and the shadows of trees have a significant impact on the thermal balance of the surrounding atmosphere. This act must be planned to optimize the benefits of vegetation. A key challenge today is thus the development of a microclimatic simulation model capable of reproducing the climatic conditions of a street, or even a vegetated urban neighborhood, with the aim of proposinga decision support tool for the development of sustainable cities. The aim of this thesis is to study how to consider vegetation and especially trees, in a 30 microclimatic model to simulate the microclimate of a neighborhood. Two models, LASER/F and RATP were applied at the scale of a tree and an urban park to carry out this study.
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Prognóstico das variáveis meteorológicas e da evapotranspiração de referência com o modelo de previsão do tempo GFS/NCEP / Prediction of meteorological variables and reference evapotranspiration with GFS/NCEP weather forecast modelOliveira Filho, Celso Luís de 31 July 2007 (has links)
Avaliou-se o desempenho de um modelo numérico de previsão do tempo (GFS - Global Forecast System – antigo AVN – AViatioN model - do Centro Nacional para Previsão Ambiental – NCEP) no prognóstico de variáveis meteorológicas temperatura, déficit de pressão de vapor do ar, saldo de radiação e velocidade do vento, e da evapotranspiração de referência calculada pelos métodos de Thornthwaite (1948) e de Penman-Monteith (Allen et al., 1998). O desempenho foi avaliado por comparação com dados provenientes de uma estação meteorológica, situada em Piracicaba, São Paulo. A temperatura e o déficit de pressão de vapor do ar foram os elementos melhor prognosticados, com desempenho "muito bom" e "bom", de acordo com o índice de desempenho proposto por Camargo e Sentelhas (1997), para no máximo quatro e três dia de antecedência, respectivamente, durante o período seco. Para o período úmido, somente o prognóstico do déficit de pressão de vapor do ar para o primeiro dia mostrou-se "bom". Os prognósticos de saldo de radiação e velocidade do vento foram ruins para ambos os períodos. Em decorrência do bom desempenho do modelo para prognosticar a temperatura, verificou-se que a estimativa de ETo pelo método de Thornthwaite teve boa concordância com o calculado a partir dos dados da estação meteorológica, com antecedência de até três dias para o período seco. Para o úmido, este fato foi observado apenas para o primeiro dia de antecedência. A concordância entre os valores estimados pelo modelo e a partir da estação para o método de Penman-Monteith foi muito baixa, em conseqüência do desempenho do modelo de previsão do tempo em prognosticar o saldo de radiação e a velocidade do vento. / The performance of a numeric weather forecast model (GFS- Forecast System, former AVN - AvatioN model, National Center for Environmental Prediction-NCEP) was evaluated for predicting weather variables, like air temperature and vapor pressure deficit, net radiation and wind speed, as well as reference evapotranspiration calculated by Thornthwaite (1948) and Penman-Monteith (Allen et al., 1948) methods, by the comparison with data obtained by an automatic weather station, in Piracicaba, State of São Paulo, Brazil. Temperature and vapor pressure deficit were the variables predicted with the best accuracy, with a "very good" and "good" performance, according to the index of confidence proposed by Camargo and Sentelhas (1997), for the maximum of four and three days in advance, respectively, during the dry season. For the wet season, only vapor pressure deficit was predicted with a "good" performance of the model. The predictions of net radiation and wind speed were very poor for both seasons. As the weather forecast model predicted temperature well, ETo estimated by Thornthwaite method showed a good agreement with ETo values estimated by observed data from the weather station, with till three days in advance for the dry season. For the wet season, such agreement was observed just for one day in advance. When ETo estimated by Penman-Monteith method with data from the weather forecast model and from weather station were compared any agreement was observed, which was caused by the poor performance of the numeric weather forecast model to predict net radiation and wind speed.
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Aprimoramento do zoneamento agrícola de risco climático do sistema de produção da soja em Mato Grosso do Sul / Improvements on the agricultural climate risk zoning of soybean production system in Mato Grosso do Sul, BrazilComunello, Éder 11 February 2016 (has links)
Mato Grosso do Sul (MS) é um estado brasileiro cuja economia é fortemente dependente da atividade agrícola, sendo diretamente afetado pelas flutuações das safras. Soja e milho são as principais culturas exploradas, chegando a representar 96% dos cultivos temporários. Perdas agrícolas decorrentes de adversidades climáticas são relativamente frequentes nesses cultivos, sobretudo por déficit hídrico. Nesse sentido, estratégias que minimizam perdas, como o Zoneamento Agrícola de Risco Climático (ZARC), são essenciais para garantir o sucesso dos produtores. Todavia, o ZARC não está isento de falhas, requerendo ajustes e melhorias, face às grandes alterações que ocorreram no processo produtivo nas últimas décadas, dentre as quais a ampliação e a atualização da base de dados meteorológicos empregada na determinação dos riscos e o uso de coeficientes de cultura (Kc) atualizados, especialmente no caso da soja com hábito de crescimento indeterminado. Desse modo, os objetivos deste estudo foram: a) comparar o desempenho de duas diferentes estruturas lisimétricas para a obtenção da evapotranspiração das culturas (ETc) da soja e do milho; b) determinar localmente os valores de Kc, com base na lisimetria (ETc) e na evapotranspiração de referência de Penman-Monteith (ETo), considerando cultivares de soja com hábitos de crescimento determinado e indeterminado; c) gerar mapas atualizados de risco climático para a cultura da soja em MS, considerando-se novos Kc e a ampliação da base de dados, para distintas épocas de semeadura; e d) avaliar épocas de semeadura da soja em MS e seus efeitos no risco climático. Os resultados mostraram que as estruturas lisimétricas podem ser empregadas na determinação da ETc, sem diferenças significativas (p < 0,01), apesar das peculiaridades de cada uma. Assim, foi constatado que as determinações de Kc (milho e soja) não sofreram influência do tipo de lisímetro utilizado. Em todos os experimentos realizados, as plantas do interior dos lisímetros apresentaram o mesmo padrão de crescimento, desenvolvimento e produtividade do entorno. Na fase inicial da cultura do milho outonoinverno (0-15 DAE), o Kc médio obtido foi 0,54, com incremento linear até atingir o máximo de 1,37 no pendoamento (50 DAE), decaindo gradualmente durante a fase reprodutiva, ficando próximo a 0,80 na maturação fisiológica (110 DAE) e 0,40 na colheita. Para a cultura da soja, os valores de Kc diferiram significativamente (p < 0,05) entre as cultivares com diferentes hábitos de crescimento, havendo também diferenças entre os Kc propostos nesse estudo em relação àqueles utilizados pelo ZARC e FAO, especialmente na fase reprodutiva, mais longa para as cultivares de hábito indeterminado. Finalmente, o emprego de novos Kc e uso de dados climáticos atualizados (até 2013) e ampliados (190 estações) resultou em mudanças substanciais no ZARC da soja em MS, alterando a proporção de áreas com alto risco nas épocas avaliadas e levando à uma perspectiva diferenciada da antecipação da semeadura da soja. Com base nesses resultados concluiu-se que é necessária uma profunda revisão do ZARC utilizado no Brasil, sendo recomendada a atualização e expansão da base de dados climáticos empregados, assim como a revisão dos parâmetros culturais exigidos pelo modelo Sarra. / Mato Grosso do Sul (MS) is a Brazilian state whose economy is highly dependent on agriculture, being, therefore, directly affected by fluctuations on production. Soybean and maize are the main crops, representing 96% of temporary crops cultivated along the year. Agricultural losses caused by adverse climatic conditions are relatively frequent in these crops, especially by water deficit. Considering that, strategies for minimizing losses, as the Agricultural Climate Risk Zoning (ZARC), are essential to ensure growers success. However, the ZARC requires adjustments and improvements, due the great changes that have occurred in the production system in the past decades. Among the most important changes are the expansion and updating of the climatic database used for determining the risks and the use of new crop coefficients (Kc) concerning to modern cultivars, especially for soybean with indeterminate growth habit. Therefore, this study has as objectives: a) to compare the performance of two different lysimetric structures to obtain soybean and maize evapotranspiration (ETc); b) to determine Kc values for maize and for determinate and indeterminate soybean cultivars, based on ETc from lysimeters and Penman-Monteith reference evapotranspiration (ETo); c) to generate updated maps of climatic risk for the soybean crop in MS, considering new Kc values and the updated and extended climatic databases, for different sowing dates; and d) to evaluate different sowing dates in MS and their impacts on soybean climatic risk. The results showed that lysimetric structures can be employed to determining ETc without significant differences (p < 0.01), despite the peculiarities of each one. Kc values for maize and soybean were not affected by lysimeter type. In all experiments, the plants inside the lysimeters had the same growth patterns than those in the surrounding area. For autumn-winter maize crop, the average Kc from 0 to 15 days after emergence (DAE) was 0.54, with a linear increase up to the maximum of 1.37 at tasseling (50 DAE), gradually decreasing during the reproductive phase, getting close to 0.80 at physiological maturity (110 AED) and 0.40 at harvest. For soybean, Kc values differed significantly (p < 0.05) between cultivars with distinct growth habits, and also among those proposed here and used by ZARC and FAO, mainly during the reproductive phase, which was longer for indeterminate cultivars. Finally, the use of new soybean Kc values and updated climatic data (190 stations with data until 2013) resulted in substantial changes on the soybean ZARC in MS, mainly in the proportion of areas with high risk, leading to new perspectives about soybean sowing anticipation. The main conclusion of this study is that ZARC used in Brazil requires to be deeply reviewed, for both the climatic database used and crop parameters required by Sarra model.
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Evapotranspiração e coeficiente de cultura em dois ciclos de produção do maracujazeiro amarelo. / Evapotranspiration and crop coefficient in two cycles of production of yellow passion fruit.Corrêa, Rodrigo Alessandro de Lima 17 May 2004 (has links)
Este trabalho teve como objetivo determinar a evapotranspiração da cultura (ETc) e o coeficiente de cultivo (Kc) do maracujazeiro amarelo (Passiflora edulis Sims f. flavicarpa Deg), durante 637 dias após o transplantio (DAT) das mudas. O experimento foi desenvolvido na área experimental da Fazenda Areão pertencente à ESALQ/USP, em Piracicaba, SP. A determinação da ETc foi realizada em 4 lisímetros de drenagem, instalados no centro de uma área de 0,4 ha cultivada com maracujazeiro amarelo, no espaçamento de 3,5 m x 4,0 m, desde 21/05/99 (17 DAT). A determinação do Kc foi realizada a partir da evapotranspiração de referência (ETo) estimada pelo método de Penmam-Monteith, considerando a evapotranspiração das plantas daninhas no somatório da evapotranspiração da cultura (ETcm). No período entre 32 e 91 DAT foram verificados baixos valores de ETc, devido a ocorrência de baixas temperaturas e radiação solar. A partir dos 91 DAT os valores foram crescentes atingindo o valor máximo de 23,37 L planta-1 d-1 no período compreendido entre 287 e 308 DAT, máximo florescimento e frutificação. Considerando a área total do espaçamento, com ervas daninhas ocupando as entrelinhas, este valor foi de aproximadamente 2,68 mm d-1. Verificou-se que em condições de irrigação na área total, a evapotranspiração das plantas daninhas das entrelinhas deve ser considerada, pois podem corresponder a até 90% da evapotranspiração total da área. O consumo hídrico total no primeiro ciclo de produção foi de 650 mm em 447 dias, com acúmulo térmico de 5880 graus-dia. Os valores médios de Kc aumentaram de 0,24 a 0,89 seguindo o aumento da área foliar, observada em função da projeção da copa que variou de 0,06 a 4 m2. Durante o ciclo do maracujazeiro foram determinados 6 estádios de desenvolvimento, com valores de Kc de 0,3 para a fase de desenvolvimento inicial, 0,4 para a fase de crescimento vegetativo apical, 0,5 para a fase de crescimento vegetativo lateral, 0,9 para a fase de florescimento, frutificação e maturação dos frutos, 0,8 para a fase de repouso vegetativo e 0,7 para o início do florescimento e frutificação do segundo ciclo de produção. / This work had as objective to determine the crop evapotranspiration (ETc) and the crop coefficient (Kc) of yellow passion fruit (Passiflora edulis Sims f. flavicarpa Deg), during 637 days after the transplant (DAT) of the seedling. The experiment was carried out in the experimental field of Fazenda Areão which belongs to ESALQ/USP, in Piracicaba, São Paulo State, Brazil. The determination of the ETc was made in 4 drainage lysimeters, installed in the center of an area of 0.4 ha cultivated with yellow passion fruit, in the space distance of 3.5 m x 4.0 m, since 05/21/99 (17 DAT). The determination of Kc was accomplished by the evapotranspiration reference (ETo) estimated by Penmam-Monteith Method, considering the weed evapotranspiration in the amount of the crop evapotranspiration (ETcm). In the period between 32 and 91 DAT low values were verified of ETc, due to the low temperature and solar radiation. Through of 91 DAT the values increased and reached the maximum value of 23.37 L d-1 p-1 in the period comprised between 287 and 308 DAT, maximum flowering and fruit set. Considering the total area of the spacing, with weeds occupying the interlineations, this value was of approximately 2.68 mm d-1. It was verified that under irrigation conditions in the total area the evapotranspiration of the weeds of the interlineations should be considered, therefore they can correspond up to 90% of the total evapotranspiration of the area. The total crop evapotranspiration in the first production cycle was of 650 mm in 447 days, with thermal accumulation of 5880 degree day. The average values of Kc increased from 0.24 to 0.89 following the increase of the leaf area, it was observed in function of the projection of the cup that varied from 0.06 to 4 m2. The cycle of the passion fruit showed 6 development phases, with values of Kc 0.3 for the initial development phase, 0.4 for the growth vegetative phase, 0.5 for the lateral vegetative growth phase, 0.9 for the flowering phase, fruit set and maturation of the fruits, 0.8 for the vegetative rest phase and 0.7 for the beginning of the flowering and fruit set of the second production cycle.
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Evapotranspiração de cafezal semi-adensado irrigado por gotejamento e sua relação com a evapotranspiração de referência / Evapotranspiration in a drip-irrigated hedgerow-coffee plantation and its relationship with the reference evapotranspirationKarasawa, Shiguekazu 28 July 2006 (has links)
O uso crescente de irrigação na cafeicultura devido ao cultivo em áreas com maior deficiência hídrica exige conhecimento sobre o consumo de água da cultura. Para contribuir para esse conhecimento, a evapotranspiração global do cafezal (ETc) e sua partição nos fluxos componentes evapotranspiração das linhas de cafeeiros (ETlin), evapotranspiração das entrelinhas (ETel) e a transpiração dos cafeeiros (T) foram determinadas em um cafezal de Coffea arabica cv. Obatã IAC-1669-20, cultivado em Piracicaba, SP, em espaçamento de 3,50 m x 0,90 m, irrigado por gotejamento e idade entre 3 a 4 anos, com medidas de setembro/04 a maio/05 e em setembro e outubro de 2005. ETc foi determinada pelo método de balanço de energia-razão de Bowen, ETlin por lisímetros de células de carga, sendo estes usados em vários períodos com o solo coberto com plástico para determinação direta da transpiração e para calibrar o método da sonda de dissipação térmica, usado na determinação do fluxo de seiva (FS) dos cafeeiros. Em abril-maio/05, FS foi usado como uma estimativa de T diária. ETc e componentes foram relacionados com a evapotranspiração de referência estimada pelos métodos de Penman- Monteith (ETo 1) e do tanque classe A (ETo 2). O calor latente de vaporização (LE) representou a maior fração na partição da energia disponível (saldo de radiação menos fluxo de calor no solo), com variação de 73 a 80 % ao longo dos meses, não se podendo descartar a contribuição de calor advectivo para os valores encontrados nos meses secos. ETc cresceu a partir de setembro/04 a fevereiro/05 (2,75 a 4,58 mm d-1), refletindo principalmente o incremento de área foliar e diminuindo, posteriormente, até maio/05 (3,13 mm d-1) com a diminuição da demanda atmosférica. Em setembro-outubro/05 os valores foram maiores (2,93 e 4,29 mm d-1) do que os observados no mesmo período em 2004, sendo o aumento da área foliar uma das responsáveis pelo fato. A relação ETc/ETo ("Kc global da cultura") foi maior quando calculada com ETo 1 do que com ETo 2, sendo os valores crescentes até janeiro/05 (1,20 com ETo 1 e 1,21 com ETo 2) mas com o menor valor em setembro/04 (0,67 e 0,54) e com diminuição da tendência de acréscimo em fevereiro/05 (1,17 e 0,73), provavelmente pela regulação estomática dos cafeeiros devido à alta demanda atmosférica nesses meses. A contribuição de ETlin para a ETc variou pouco entre setembro/04 e fevereiro/05 (24 % a 31 %), aumentando em março e abril (35 % e 40 %), valores esses próximos da proporção entre a área de solo coberta pelos cafeeiros e a área total (linhas+entrelinhas). A relação ETlin/ETo variou entre 0,20 (uso de ETo 1) e 0,16 (com ETo 2) em setembro/04 a 0,36-0,47 (com ETo 1) e 0,25-0,49 nos outros meses. A T dos cafeeiros por unidade de área foliar diminuiu com o aumento da área foliar. A relação T/ETlin variou de 72 % em fevereiro a 46 % em abril, sendo o valor de T/ETo ("Kc basal") variável entre 0,13 (com ETo 1) e 0,10 (com ETo 2) em setembro a 0,30 (independente do método de estimativa de ETo) em abril e maio/04, provavelmente refletindo a menor atividade fisiológica. / The increasing use of irrigation in coffee plantations in Brazil, due to the deplacement of the crop to areas where water deficit occurs, requires knowledge about crop water consumption. Aiming to know more about coffee plantation water consumption, daily crop evapotranspiration (ETc) and its partition in row evapotranspiration (ETrow), interrows evapotanspiration (ETint) and coffee plants transpiration (T) were determined in a drip-irrigated coffee plantation (cv. Obatã IAC-1669-20), cultivated at 3.5 m between rows and 0.9m between plants, in Piracicaba, São Paulo State, Brazil. The ET and wheater variables measurements were carried out from September 2004 to May 2005 and from September to October 2005. ETc was determined by he Bowen ratio-energy balance method, ETrow by load cell lysimeters and T with lysimeters with soil surface covered with plastic or by sap flow determined with the thermal dissipation probe method (TDP). Lysimeters were also used to calibrate the TDP method. So, sap flow was adopted as representative of coffee plants transpiration for 24-h period. ET and its components were related to the reference evapotranspiration, determined by Penman-Monteith (ETo 1) and Class-A pan (ETo 2) methods. Latent heat of vaporization (LE) represented the major fraction (73 a 80 %) of the available energy (net radiation less soil heat flux) along the months, but a contribution of advective heat flux in dry months must be considered for the observed values. ETc increased from September 2004 to February 2005 (from 2.75 to 4.58 mm d-1), which is reflecting the increase of coffee plants leaf area. From March to May 2005, ETc decreased according to the decrease of the atmospheric demand. In September and October 2005, ETc were greater, respectively, 2.93 and 4.29 mm d-1, than those observed in the same months of 2004 and, again the increase of leaf area was the responsable for these differences. ETc/ETo, defined as a "global Kc", was greater when determined with ETo 1 than when determined with ETo 2, increasing with the leaf area.from September 2004 (0.67 with ETo 1 and 0.54 with ETo 2) to January 2005 (1,20 and 1,21). In February Kc decreased to 1.17 (with ETo 1) and 0.73 (with ETo 2), probably as a consequence of the coffee plants stomatal control due to the high atmospheric demand. The contribution of ETrow to ETc varied between 25 % and 31 % for the period September 2004- February 2005, increasing in March and April 2005 (35 % and 40 %). These values were close to those observed for the ratio between the area of soil covered by coffee plants and the total area (rows+interrows). ETlin/ETo changed from 0.20 or 0.16 (using ETo 1 and ETo 2, respectively) in September 2004 to 0.36-0.47 (with ETo 1) or 0.25- 0.49 (with ETo 2) in the other months. Coffee plant transpiration per leaf area unit decresead with the increase of leaf area. T/ETrow changed from 0.72 (February) to 0.46 (April). T/ETo ("basal Kc") ranged from 0.13 (with ETo 1) or 0.10 (with ETo 2) in September 2004 to 0.30 (for both ETo 1 or ETo 2) in February, but decreased in April and May 2005, probably reflecting the decrease in the physiological activity of coffee plants.
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