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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The utilization of Bowen Family Systems Theory in teaching healthy corporate life in congregations implications and applications /

Thomasma, Norm J. January 2001 (has links)
Thesis (D. Min.)--Trinity International University, 2001. / Abstract. Includes bibliographical references (leaves 169-171).
52

Emergence de la dimension environnementale de la RSE : une étude historique franco-québécoise d'EDF et d'Hydro-Québec / Emergence of the environmental dimension of CSR : A France-Québec historical study of EDF and Hydro -Québec

Berrier-Lucas, Céline 24 October 2014 (has links)
Cette thèse étudie la dimension environnementale de la RSE. Les enjeux actuels que pose la soutenabilité nécessitent de déconstruire le concept le RSE pour révéler les sous-jacents qui structurent le champ académique Business & Society. Au travers d’une approche historique et comparative, cette recherche suit les traces que les enjeux socio-environnementaux laissent dans les controverses qu’ils déploient, dans les relations qu’ils nouent et dans les compromis qu’ils établissent auprès des humains et des non-Humains lors de la construction de quatre aménagements énergétiques en France (le barrage hydroélectrique de Tignes et l’usine marémotrice de la Rance) et au Québec (le barrage hydroélectrique de Bersimis et la centrale nucléaire de Gentilly) durant les années 1945 jusqu’aux années 1970. Dans la lignée des travaux qui développent une compréhension non dichotomique de la nature et de la culture en prenant comme point d’appui le refus de l’ontologie Moderne (Latour ; Descola ; Gladwin, Kennely et Krause ; et Banerjee etc.), elle éclaire les associations/dissociations réalisées au sein de collectif d’alliés hétérogènes et revisite la catégorisation des années 1970 dite de « tournant environnemental », grâce à l’analyse précise de l’ouvrage du père fondateur de la RSE, Howard R. Bowen Social Responsibilities of the Businessman (1953), en éclairant ses héritages théoriques. Cette thèse vise trois contributions. D’abord, elle affine l’approche « naturaliste » ou « Moderne » selon deux perspectives empirique et cognitif et selon deux modes de relation au collectif le réalisme et le nominalisme. Puis, elle inscrit la littérature de la RSE dans l’ontologie Moderne en montrant des filiations théoriques dans le courant conservationniste de la wilderness. Enfin, elle mobilise l’approche relationnelle pour analyser les enjeux socio-environnementaux et propose une autre appréhension de la RSE fondée sur une vision dynamique et relationnelle de la responsabilité où les frontières classiques de l’environnement des entreprises sont éclatées au profit de réseaux socio-environnementaux. / This dissertation studies the environmental dimension of CSR. Current issues raised by sustainability need to deconstruct the concept of CSR to reveal the underlying structure of the Business & Society academic field. Through historical and comparative approaches, this research follows the trail that socio-Environmental issues leave in the controversies they deploy, in the relationships they forge and in compromises they establish with human and non-Humans through the construction of four energy facilities in France (Tignes’ hydroelectric dam and La Rance’ tidal power plant) and Quebec (Bersimis’ hydroelectric dam and Gentilly’ nuclear plant) during the 1945th until the 1970th. In the line of work that develop non dichotomous understanding of the nature and culture by taking the refusal of Modern ontology (Latour; Descola; Gladwin, Kennely and Krause, and Banerjee etc.) as a base, it sheds light on associations/dissociations performed within heterogeneous group of allies and revisits "environmental turn" thanks to the precise analysis of the work of the founding father of CSR, Howard R. Bowen Social Responsibilities of the Businessman (1953), illuminating its theoretical legacies. This research aims at making three contributions. First, it refines the "naturalistic" approach or "Modern" in two empirical and cognitive perspectives and two modes of relating to collective: realism and nominalism. Then it entered the literature of CSR into the Modern ontology by showing theoretical legacies in wilderness conservation. Finally, it mobilizes the Amodern approach to analyze the socio-Environmental issues, and proposes an alternative understanding of CSR based on a dynamic and relational view of responsibility where the traditional boundaries of the business environment are broken in favor of socio-Environmental networks.
53

Modelagem da evapotranspiração em plantios de eucalipto em fase inicial de desenvolvimento com cobertura parcial do solo / Modeling of evapotranspiration in eucalyptus plants in initial stage of development with partial coverage of the soil.

Souza, Wesley Gonçalves de 21 September 2006 (has links)
Made available in DSpace on 2015-03-26T13:50:18Z (GMT). No. of bitstreams: 1 texto completo.pdf: 478082 bytes, checksum: 5e70d0378d5af63ea956dca05531ef66 (MD5) Previous issue date: 2006-09-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Species of the gender Eucalyptus, whose characteristics as fast growth and capacity of resisting to the water stress, they are used in wide climbs in the establishment of industrial forests in several countries, among which ones, highlights Brazil with more than 3 million planted hectares. The tropical and subtropical climate in most of the Brazilian territory allows an uninterrupted growth and, consequently, a fast biomass accumulation. It is known that the growth and the development of the vegetables is consequence of several physiologic processes, which are controlled by the environmental conditions and characteristic genetics of each vegetable species. Therefore, for best to understand the growth, the development and the impact hydrology of an eucalyptus plantation, it is done necessary to know the factors that control the use of the water. Several environmental factors influence the opening and the closing stomatic, determining larger or smaller transfer of water vapour for the atmosphere. Among these, they highlight the levels of humidity of the soil, the tenor of humidity of the air, solar radiation, temperature of the air and vapour pressure deficit. Specifically, plants with initial age of development present discontinuity in the covering of the soil, being these subject isolated plants the largest interaction with the atmosphere, tending to present larger exhibition of the canopy to the wind and the solar radiation, for that, the given aerodynamic treatment the those plants should be different in relation to plants in adult age, with total covering of the soil. Usually, the growth models consider in the estimate of the conductance of surface of the water vapour the canopy as a leaf big, only and continuous (theory of "Big Leaf"). This approach is not adapted in the initial stage of development of forests. This age in relation to the another have a great importance, once in that period the plants present larger growth rate, once the biomass earnings is directly related to the evapotranspiration processes (loss of water vapour) and photosynthesis (earnings of CO2). In this context, the objective of this study was to model the evapotranspiration for eucalyptus plants in initial phase of development. The experimental site is located in an area belonging to Aracruz Celulose in city of Aracruz, state of Espírito Santo. The meteorological data, solar radiation, temperature of the air, relative humidity, speed of the wind and precipitation were collected in a tower of 38 m of located height among four trees. The methodology used in the modelling of the evapotranspiration was based in the work of Angelocci (1996), when the same in his study made estimates for the evapotranspiration of apple trees in orchards. For the comparison of the results, he esteemed the evapotranspiration by the method of the Bowen Ration for being this a method that describes the relationship soil-plant- atmosphere well. After the analysis of the results for the whole studied period, it verified that to the initial stage of development of the eucalyptus, the developed model showed efficient in the estimate of the evapotranspiration. / Espécies do gênero Eucalyptus, cujas características como crescimento rápido e capacidade de resistir ao estresse hídrico, são utilizadas em larga escala no estabelecimento de florestas industriais em vários países, entre os quais, destaca-se o Brasil com mais de 3 milhões de hectares plantados. O clima tropical e subtropical na maioria do território brasileiro permite um crescimento ininterrupto e, consequentemente, um rápido acúmulo de biomassa. Sabe-se que o crescimento e o desenvolvimento dos vegetais é conseqüência de vários processos fisiológicos, os quais são controlados pelas condições ambientais e características genéticas de cada espécie vegetal. Portanto, para melhor compreender o crescimento, o desenvolvimento e o impacto hidrológico de uma plantação de eucalipto, faz-se necessário conhecer os fatores que controlam o uso da água. Vários fatores ambientais influenciam a abertura e o fechamento estomático, determinando maior ou menor transferência de vapor de água para a atmosfera. Dentre estes, destacam-se os níveis de umidade do solo, o teor de umidade do ar, radiação solar, temperatura do ar e déficit de pressão de vapor. Especificamente, plantios com idade inicial de desenvolvimento apresentam descontinuidade na cobertura do solo, ficando estas plantas isoladas sujeitas a maior interação com a atmosfera, tendendo a apresentar maior exposição do dossel ao vento e a radiação solar, por isso, o tratamento aerodinâmico dado a esses plantios deve ser diferente em relação a plantios em idade adulta, com cobertura total do solo. Normalmente, os modelos de crescimento consideram na estimativa da condutância de superfície do vapor de água o dossel como uma folha grande, única e contínua (teoria da Big Leaf ). Esta aproximação não é adequada na etapa inicial de desenvolvimento de florestas. Esta idade em relação às outras tem uma grande importância, uma vez que nesse período as plantas apresentam maior taxa de crescimento, uma vez que o ganho de biomassa está diretamente relacionado aos processos de evapotranspiração (perda de vapor d água) e fotossíntese (ganho de CO2). Neste contexto, o objetivo deste estudo foi modelar a evapotranspiração para plantios de eucalipto em fase inicial de desenvolvimento. O sítio experimental está localizado numa área pertencente à Aracruz Celulose no município de Aracruz ES. Os dados meteorológicos, radiação solar, temperatura do ar, umidade relativa, velocidade do vento e precipitação foram coletados em uma torre de 38 m de altura localizada entre quatro árvores. A metodologia utilizada na modelagem da evapotranspiração baseou-se no trabalho de Angelocci (1996), quando o mesmo em seu estudo fez estimativas para a evapotranspiração de macieiras em pomares. Para a comparação dos resultados, estimou-se a evapotranspiração pelo método da Razão de Bowen por ser este um método que descreve bem a relação solo-planta-atmosfera. Após a análise dos resultados para todo o período estudado, verificou-se que para os estádios iniciais de desenvolvimento do eucalipto, o modelo desenvolvido se mostrou eficiente na estimativa da evapotranspiração.
54

Estimativa do balanço de energia a partir de medidas de protótipo de estação micrometeorológica

Silva Filho, Armando da 04 March 2015 (has links)
Submitted by Jordan (jordanbiblio@gmail.com) on 2017-05-03T13:16:15Z No. of bitstreams: 1 DISS_2015_Armando da Silva Filho.pdf: 2167850 bytes, checksum: 8a936f786a917c577b5eda9b7742b84a (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-05-04T15:39:52Z (GMT) No. of bitstreams: 1 DISS_2015_Armando da Silva Filho.pdf: 2167850 bytes, checksum: 8a936f786a917c577b5eda9b7742b84a (MD5) / Made available in DSpace on 2017-05-04T15:39:52Z (GMT). No. of bitstreams: 1 DISS_2015_Armando da Silva Filho.pdf: 2167850 bytes, checksum: 8a936f786a917c577b5eda9b7742b84a (MD5) Previous issue date: 2015-03-04 / CNPq / A conversão de extensas áreas de Cerrado para culturas agronômicas e em área urbana modifica o microclima, possível de ser medido pelo balanço de energia. No entanto, os equipamentos micrometeorológicos possuem elevado custo de aquisição. Sendo assim, esta pesquisa tem por objetivo desenvolver uma estação micrometeorológica capaz de medir o balanço de energia pelo método da razão de Bowen em uma área de cana-de-açúcar e em uma área urbana no município de Barra do Bugres, Mato Grosso. Neste trabalho foram desenvolvidos saldo radiômetros, piranômetros, fluxímetros de calor no solo, termohigrômetros e datalogger. Esses sensores foram postos para calibração em condições semelhantes à sensores comerciais, e depois instalados em um mastro localizado em uma área de cana-deaçúcar e uma urbana. O balanço de energia foi estimado pelo método da razão de Bowen. As correlações do piranômetro, saldo radiômetro, temperatura do ar, e umidade relativa, foram superiores a R2= 0,98 e o fluxímetro de calor do solo R2= 0,90. O custo da estação desenvolvida representou 4,3% do custo de uma estação comercial e a correlação dos sensores desenvolvidos indicam a viabilidade de seu uso em estudos científicos. Nos testes de campo o saldo de radiação foi utilizado prioritariamente para o fluxo de calor latente, 56,7% e 43,8%, seguido pelo fluxo de calor sensível, 39,6% e 25,6%, e no solo, 3,6% e 30,5% na área de cana-de-açúcar e urbana, respectivamente. / The conversion of large areas of Cerrado for agronomic crops and in urban areas modifies the microclimate, can be measured by the energy balance. However, the micrometeorological equipment have a high cost. Thus, this research aims to assess the development of a micrometeorological station capable of measuring the energy balance by Bowen ratio method in an area of sugar cane and in an urban area in the municipality of Barra do Bugres, Mato Grosso. In this work were developed balance radiometers, pyranometers, heat meter in the soil and termohigrômetros. These sensors we reset for calibration in conditions similar to commercial sensors, and then installed on a mast located in an area of sugar cane and urban. The energy balance was estimated by the Bowen ratio method. The pyranometer of correlations, balance radiometer, air temperature, and relative humidity, were greater than R2=0.98 and heat meter in the soil R2= 0.90. The net radiation was used primarily for the latent heat flux, 56.7% and 43.8%, followed by the sensible heat flux, 39.6% and 25.6%, and soil, 3.6% and 30.5% in the area of sugar cane and urban, respectively.
55

Portfolio of compositions [music] : Rothko's red (orchestral tone poem) ; The portrait : a musical tribute to Stella Bowen (music theatre work) / Becky Llewellyn

Llewellyn, Rebecca Ann January 2007 (has links)
The portfolio contains two of Becky Llewellyn’s music compositions: an orchestral tone poem and a chamber opera score and libretto created to explore the process of producing a major work of music theatre from conception to performance. In both works, Llewellyn’s research has concentrated on her interest in structure and form between ideas, music and visual art and their relationship to each other. Rothko’s Red The first composition in her submission is her orchestral tone poem, Rothko’s Red, a tribute to US artist Mark Rothko, whose painting techniques questioned traditional forms of narrative and structure. The topographical matrix of Rothko’s Red contains vertical aural space introduced in a ‘keyed up’ range suggesting ‘redness’, gradually deepening until the bass predominates, retaining a widened spaciality at the peak moment. Horizontally, the piece is a long crescendo of extended phrases, at first lightweight, then filling out with each repetition, moving to a full expression of orchestral magnitude, then gradually subsiding. The tone poem passes limited melodies and harmonies around to and within the orchestral families, as if in one colour. Llewellyn’s use of individual dynamics for orchestral players is an experiment in aural equivalence of Rothko techniques, using ‘heard’, not ‘seen’ tone colours. The Portrait: a musical tribute to Stella Bowen Llewellyn’s chamber opera is based on books, letters, diaries and family history research into the life of Adelaide-born writer and painter, Stella Bowen and three other writers. The opera’s libretto is structured as a series of songs reflecting Bowen’s paintings and life story. The chamber opera opens and closes in 1944, with Bowen as a WWII Australian war artist. The opera spans from 1917, when as a London art student, Bowen is introduced to editor/writer, Ford Madox Ford with whom she falls in love. The opera moves through to Paris and Ford’s subsequent love affair with writer Jean Rhys and his death in 1939. The Portrait is an exploration of how we know who we are and how, as artists, we choose to represent those insights. As the four main characters each wrote about themselves and each other, Llewellyn used their distinct content, style and aesthetic concerns to invent their musical and dramatic personae. The Portrait plays with ideas these four artists explored of extended metaphors, a shifting ambiguity in ‘artifice as a real story’, in an imagined dramatic musical work about real artists and writers; life as art and art as life. Among other themes in The Portrait; thanatos and eros, culture and morality, war and peace, fate and choice and opera as portraiture, is an underlying structural theme of time itself. Mythic time is explored as fairytale. Historical time ranges from 1920s chordal and dance motifs back to associations of medieval castles, where western-style Romantic love began. Personal, subjective experience of time is explored by most characters, as is the lack of artistic time given domestic commitments. Objective ‘time as limited’ is explored with Ford’s death and the impending death of the Australian bomber crew. Llewellyn focuses on the timebased art-form of music, while incorporating words, Bowen’s paintings and archival photographs in a chamber opera that explores the potential each art-form carries for revelation. / Thesis (M.Mus.) -- University of Adelaide, Elder Conservatorium of Music, 2007
56

Cleat mineralogy of later permian coal measures, Bowen Basin, Queensland, Australia

Faraj, Basim Said. Unknown Date (has links)
No description available.
57

Cleat mineralogy of later permian coal measures, Bowen Basin, Queensland, Australia

Faraj, Basim Said. Unknown Date (has links)
No description available.
58

Evapotranspiração e eficiência produtiva da videira Syrah no Submédio do vale do São Francisco / Evapotranspiration and productive efficiency of the vine "Syrah" in the valley São Francisco river

Pereira, Vágna da Costa 21 February 2014 (has links)
Made available in DSpace on 2015-03-26T13:50:18Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1701700 bytes, checksum: c751f2ca881cfb2b5b10f7e2636abb8d (MD5) Previous issue date: 2014-02-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The determination of water consumption by the grape vine becomes crucial to obtain satisfactory yields for the preparation of fine wines, reduction of production costs, and mainly for the sustainable management of regional water resources. Thus, this study aimed to examine the values of grape winemaking crop evapotranspiration, determined by two methods (energy balance based on the Bowen ratio (BERB) method and the Penman-Monteith model), and the crop efficiency of water use to the climatic conditions of SVSF. The experiment was conducted in a commercial area of Fazenda Ouro Verde (09°16'S, 40°51'W and 444 m) in the first half of 2010, located in the semiarid region of the municipality of Villa Nova, Bahia. The selected area of 9 hectares was planted with the grape vine (Vitis vinifera L.), variety "Syrah", grafted onto the rootstock IAC 766, with three years of planting and drip irrigated. Pruning production was held on March 8, 2010 and harvest on July 19, 2010, totaling a production cycle of 133 days. The results showed that, during the analysis of physical consistency of BERB method, 69.5 % of days evaluated were considered valid for determining the density of energy flows in daily scale. The net radiation and reflected radiation represented about 73 and 16% respectively of the incident solar radiation in the vineyard. Throughout the production cycle of the vine, the daily average values of the latent heat flux (LE) accounted for approximately 70% of net radiation (Rn), while 30% was used for heating of atmospheric air, represented by the flow sensible heat (H). However, no energy for heating the ground (G) for almost all phenological stages, except the final stage when the G/Rn ratio represented approximately 4%. Regarding the degree-days (GDA), 1.819 degrees were necessaries for the grapevine Syrah to complete its production cycle, corresponding to a total of 133 days for pruning in the first half of the year. The reference evapotranspiration (ETo) and crop evapotranspiration determined by the method BERB (ETcBERB) during the crop cycle were 474.0 and 376.4 mm, respectively, with a daily average of 3.9 and 3.1 mm. The maximum estimated by Penman-Monteith method ranged from 9.2 to 3.0 L d-1 m-2, respectively, with a total volume of 614.7 L m-2, about 204.9 mm. The ETcBERB/ETo ratio reached average values of 0.70, 0.85 and 0.66 for the phenological stages of sprouting-flowering, flowering, ripening and maturation to harvest. The average productivity of the vine "Syrah" to crafting fine wines was 4.400 kg ha-1, while the average productivity of water based on the total evapotranspiration and transpiration particular culture through BERB and Penman - Monteith method was 1.17 kg m-3 and 2.15 kg m-3, respectively. / A determinação do consumo de água pela videira é de crucial importância para obtenção de produtividades satisfatórias para elaboração de bons vinhos, redução de custos de produção e, principalmente, para o manejo sustentável dos recursos hídricos regional. Neste sentido, com este trabalho objetivou-se analisar os valores da evapotranspiração da cultura da uva para elaboração de vinhos, determinada por duas metodologias (balanço de energia com base no método da razão de Bowen (BERB) e o modelo de Penman-Monteith), e a eficiência do uso da água da cultura para as condições climáticas do Submédio do Vale do São Francisco (SVSF). O experimento foi conduzido em uma área comercial da Fazenda Ouro Verde (09°16 S; 40°51 O e 444 m) no primeiro semestre do ano de 2010, que fica localizada na região semiárida do município de Casa Nova, Bahia. A área de 9 hectares selecionada foi plantada com a videira (Vitis vinífera L.), variedade Syrah , enxertada sobre o porta-enxerto IAC 766, com três anos de plantio, e irrigada por gotejamento. A poda de produção foi realizada no dia 08 de março de 2010 e a colheita no dia 19 de julho de 2010, totalizando o ciclo produtivo de 133 dias. Com base nos resultados observou-se que durante a análise de consistência física do método BERB, 69,5% dos dias avaliados foram considerados válidos para a determinação da densidade de fluxos de energia em escala diária. O saldo de radiação e a radiação refletida representaram aproximadamente 73 e 16%, respectivamente, da radiação solar incidente no parreiral. Ao longo do ciclo produtivo da videira, os valores médios diários do fluxo de calor latente (LE) representaram cerca de 70% do saldo de radiação (Rn), enquanto 30% foi destinado ao aquecimento do ar atmosférico, representado por meio do fluxo de calor sensível (H). Entretanto, não houve energia destinada ao aquecimento do solo (G) durante quase todas as fases fenológicas, exceto na fase final quando a relação G/Rn representou aproximadamente 4%. Em relação aos graus-dia acumulados (GDA), foram necessários 1.819 GDA para a videira Syrah completar o seu ciclo produtivo, correspondendo ao total de 133 dias para poda no primeiro semestre do ano. A evapotranspiração de referência (ETo) e a evapotranspiração da cultura determinada por meio do método BERB (ETcBERB) durante o ciclo da cultura foram de 474,0 e 376,4 mm, respectivamente, com valor médio diário de 3,9 e 3,1 mm. A transpiração máxima estimada pelo método de Penman-Monteith oscilou entre 9,2 a 3,0 L d-1 m-2, com volume total de 614,7 L m-2, aproximadamente 204,9 mm. A razão ETcBERB/ETo atingiu valores médios de 0,70; 0,85 e 0,66, respectivamente, para as fases fenológicas de Brotação-Floração, Floração-Maturação e Maturação-Colheita. A produtividade média da videira Syrah , para elaboração de vinhos finos, foi de 4.400 kg ha-1, enquanto a média da produtividade de água com base na evapotranspiração e transpiração total da cultura determinada por meio do método BERB e Penman-Monteith foi de 1,17 kg m-3 e 2,15 kg m-3, respectivamente.
59

Crop coefficient and water demand of sugarcane at the Teresina Region, Piauà State, Brasil / Coeficiente de cultura e demanda hÃdrica da cana-de-acÃcar na microrregiÃo de Teresina, PiauÃ

DÃnavan Holanda NolÃto 27 March 2015 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / Sugarcane crop has great socio-economic importance worldwide. Brazil has the largest acreage and production volume in the world, with promising Northeast region because it has areas for expansion of the crop and stilling have a great energy potential. However, the cropping under natural water conditions limit production, making essential the use of supplemental irrigation during periods of drought. For thus its necessary studies to determine the water demand at various stages of crop development. The objective of this study was to determine the crop coefficient and water demand of sugarcane, through the energy balance method, based on the Bowen ratio, at the Teresina region, Piauà State, Brazil. The experiment was conducted at COMVAP - Sugar and Alcohol Ltda. The cultivar used was RB867515, irrigated by center pivot. The biometric analyzes were length and stem diameter, number of green leaves, leaf area and matter fresh and dry of stem, leaves and sheaths. To estimate crop evapotranspiration (ETc) was used an equipped tower with microelectronic sensors installed near the center of the growing area (10 ha plot). The reference evapotranspiration (ETo) was estimated by the Penman-Monteith method / FAO-56, based on data from a weather station located near the experiment. Soil moisture was monitored by an automated system (Time Domain Reflectometry) TDR at depths from 0 to 0.30 0.30 to 0.60 m, at four points surrounding the tower. The number of green leaves per plant ranged from six to nine, reducing to seven leaves in the end of the cycle. The stems reached approximately 3.3 m long and 2.02 kg of weight, presenting linear gains in length and mass, while its diameter remained stable (25-27 mm). The plant leaf area showed quadratic behavior, with maximum peak of 4,197 cm2 to 254 days after cutting. The balance of average daily solar radiation was 13.7, 13.2 and 16.1 MJ m-2, corresponding to 79%, 80% and 85% of the total radiation, while the coefficient clarity showed values of 0.46, 0.48 and 0.52 and the albedo of 0.15, 0.16 and 0.14, in phenological development phases II, III and IV, respectively. The physical consistency of the ETC analysis data showed that 33% of 406 days monitored were agreement. The ETc daily average was 5.3 mm, with a demand of 2,650 mm for the 498 days of the cycle. The crop coefficient (Kc) average per phase was 0.9 (fast growth), 1.32 (maximum development) and 1.07 (maturation). / A cana-de-aÃÃcar possui grande importÃncia socioeconÃmica em Ãmbito mundial. O Brasil detÃm a maior Ãrea cultivada e volume de produÃÃo no mundo, sendo a regiÃo Nordeste promissora para o setor por possuir Ãreas para expansÃo da cultura e ainda ter um Ãtimo potencial energÃtico. PorÃm, as condiÃÃes hÃdricas naturais limitam a produÃÃo, tornando essencial o uso de irrigaÃÃo complementar nos perÃodos de dÃficit hÃdrico. Para a adequada suplementaÃÃo hÃdrica da cultura necessita-se determinar a demanda hÃdrica nos diferentes estÃdios de desenvolvimento da cultura. Assim, o objetivo deste estudo foi determinar o coeficiente de cultura e a demanda hÃdrica da cana-de-aÃÃcar, por meio do mÃtodo de balanÃo de energia, com base na razÃo de Bowen, na microrregiÃo de Teresina, PiauÃ. O experimento foi conduzido na Usina COMVAP â AÃÃcar e Ãlcool Ltda., municÃpio de UniÃo, microrregiÃo de Teresina, PiauÃ. A cultivar utilizada foi a RB867515, irrigada por pivà central. As anÃlises biomÃtricas realizadas foram: comprimento e diÃmetro do colmo, nÃmero de folhas verdes, comprimento e largura da folha +3, Ãrea foliar e matÃria fresca e seca do colmo, bainhas e folhas. Para a estimativa de evapotranspiraÃÃo da cultura (ETc) usou-se uma torre equipada com sensores automÃticos, instalada prÃxima ao centro da Ãrea de cultivo (talhÃo de 10 ha). A evapotranspiraÃÃo de referÃncia (ETo) foi estimada pelo mÃtodo Penman-Monteith/FAO-56, a partir de dados de uma estaÃÃo agrometeorolÃgica localizada prÃximo ao experimento. A umidade do solo foi monitorada por um sistema automatizado com base em Reflectometria no DomÃnio do Tempo (TDR), nas profundidades de 0 a 0,30 m e 0,30 a 0,60 m, em quatro pontos no entorno da torre. O nÃmero de folhas verdes por planta variou de seis a nove, reduzindo a sete folhas ao final do ciclo. O colmo alcanÃou aproximadamente 3,3 m de comprimento e 2,02 kg de massa fresca, apresentando ganhos lineares de comprimento e massa, enquanto o seu diÃmetro permaneceu praticamente estÃvel (25 a 27 mm). A Ãrea foliar da planta demonstrou comportamento quadrÃtico, com pico mÃximo de 4.197 cm2, aos 254 dias apÃs o corte. O saldo de radiaÃÃo solar mÃdio diÃrio foi de 13,7 MJ m-2, 13,2 MJ m-2 e 16,1 MJ m-2, correspondendo a 79%, 80% e 85% da radiaÃÃo global, enquanto o coeficiente de claridade apresentou valores de 0,46, 0,48 e 0,52 e o albedo de 0,15, 0,16 e 0,14, nas fases II, III e IV de desenvolvimento fenolÃgico da cultura, respectivamente. A anÃlise de consistÃncia fÃsica dos dados de ETc mostrou que 33% dos 406 dias monitorados foram consistentes. A ETc mÃdia diÃria foi de 5,3 mm, totalizando uma demanda de 2.650 mm para os 498 dias do ciclo. O coeficiente de cultura (Kc) mÃdio por fase foi de 0,9 (crescimento rÃpido), 1,32 (mÃximo desenvolvimento) e 1,07 (maturaÃÃo).
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The impact of climate and land use on surface fluxes of matter and energy

Brust, Kristina 26 February 2019 (has links)
Changes in climate and land use interact in a complex system with various feedbacks including water, carbon (C), and nitrogen (N) fluxes. In this dissertation, firstly measurements of surface fluxes were conducted via two different measurement systems, a Bowen Ratio (BR) and an Eddy Covariance (EC) system. Over two succeeding years, fluxes and gradients of heat, water vapour, and CO2 over winter barley and rapeseed were simultaneously measured at Klingenberg, a long-term cropland site in eastern Germany. The two independent systems (EC/BR) are compared with respect to energy and CO2 fluxes. Inspection as well as a neutral regression analysis show that differences between the systems were largest for latent heat LE. EC detects apparently lower LE due to the lack of closure of the energy balance of approximately 30%, whereas the fluxes of CO2 show only smaller differences up to 10%. Therefore, Bowen Ratio setups remain an alternative to EC systems when gradients are large and analysers with high measurement frequency are not available. Encouraged by this analysis, the Modified Bowen Ratio system was used to measure the vertical gradients of mixing ratios of nitrogen oxides (NOx) and ammonia (NH3). Fluxes of these nitrogen species are analysed and associated to the corresponding growth status of two crops within two growing periods. Integration of these nitrogen fluxes results in a net emission into the atmosphere of 1.25 kg N ha-1 for the total measurement period of 77 days, differing in the proportion of NOx and NH3. However, this net emission does not largely reduce the fertilization of the crop site. In a second step, the atmospheric boundary layer model HIRVAC (HIgh Resolution Vegetation Atmosphere Coupler) was improved and applied to three different land uses within the TU-Dresden-cluster for selected time periods in 2009 and 2010. Simulated fluxes of H2O and CO2 with the improved model HIRVAC show good agreement with measurements. Realistic fluxes were obtained with respect to the diurnal cycle as well as the order of magnitude. Modelling of energy and trace gas fluxes also gives the opportunity to assess effects of changing climate conditions on surface fluxes. Since in the improved HIRVAC version a coupled model for stomatal conductance is used, an increase in CO2 concentration is linked with a decrease of stomatal conductance in the simulation. Therefore, simulations of changes in climate condition along with elevated CO2 concentrations and their effect on latent heat fluxes are analysed. The grassland and agricultural site revealed increased evapotranspiration with elevated temperatures and CO2 concentrations, whereas the forest site came up with reduced evapotranspiration rates. Concerning the flux of CO2, all land uses considered here increased the amount of assimilated carbon, whereby the forest site increased the most. Finally, the scenario calculations revealed that regarding evapotranspiration and CO2, differences of land use dominate over differences of climate change. / Veränderungen des Klimas und von Landnutzungen wirken sich in einem komplexen System mit diversen Rückkopplungen auf die Wasser-, Kohlenstoff- und Stickstoffflüsse aus. In dieser Dissertation wurden zuerst Flüsse mit zwei unterschiedlichen Methoden erfasst, einem Bowen-Ratio (BR) und einem Eddy-Kovarianz (EC) System. Dafür wurden für zwei aufeinanderfolgende Jahre Gradienten bzw. Flüsse von Wärme, Wasserdampf und CO2 über Wintergerste und Raps an einem langjährigen Agrarstandort im Osten Deutschlands (Station Klingenberg) gemessen. Die zwei unabhängigen Messmethoden (EC/BR) werden in dieser Arbeit in Bezug auf die Energie- und CO2-Flüsse miteinander verglichen. Die genaue Analyse dieser Flüsse ergibt, dass die größten Unterschiede zwischen den Messmethoden im latenten Wärmefluss (LE) vorzufinden sind. Bedingt durch die Schließungslücke von ungefähr 30 % ergibt die EC-Methode einen geringeren latenten Wärmefluss, wohingegen die Flüsse von CO2 nur Unterschiede um 10 % aufweisen. Wie der Vergleich zeigt, ist die Bowen-Ratio-Messmethode besonders dann eine wertvolle Alternative zu EC-Systemen, wenn die Gradienten der gemessenen Komponenten groß sind oder wenn Analysatoren mit hoher Messfrequenz nicht verfügbar sind. Bestärkt durch diese Ergebnisse, wurde das modifizierte Bowen-Ratio-System (MBR) verwendet, um vertikale Gradienten der Mischungsverhältnisse von Stickoxiden (NOx) und Ammoniak (NH3) zu messen. Die ermittelten Flüsse dieser Stickstoffkomponenten werden mit den Entwicklungsstadien der jeweiligen Feldfrüchte innerhalb zweier Anbauperioden in Verbindung gebracht. Die Summe der gemessenen Stickstoffflüsse ergibt eine Nettoemission in die Atmosphäre von 1,25 kg N ha-1 über die gesamte Messperiode von 77 Tagen (mit unterschiedlichen Anteilen von NOx und NH3), wobei diese Emission die Düngung der Agrarfläche nur geringfügig reduziert. Diese Ergebnisse stehen im Einklang mit Messergebnissen an anderen Agrarstandorten. Im zweiten Teil wurde das atmosphärische Grenzschichtmodell HIRVAC (HIgh Resolution Vegetation Atmosphere Coupler) überarbeitet und für drei unterschiedliche Landnutzungen innerhalb des TU-Dresden-Clusters für ausgewählte Zeitscheiben der Jahre 2009 und 2010 angewandt. Die mit dem Modell HIRVAC simulierten Flüsse von Wasser und CO2 zeigen eine gute Übereinstimmung mit den Messungen. Bezüglich des Tagesganges sowie auch in ihrer jeweiligen Größenordung wurden realistische Flüsse berechnet. Die Modellierung der Energie- und Spurengasflüsse bietet außerdem die Möglichkeit, Auswirkungen von veränderlichen klimatischen Bedingungen auf die turbulenten Flüsse zu bewerten. Da in der verbesserten HIRVAC-Version ein gekoppeltes Modell für die stomatäre Leitfähigkeit verwendet wird, ist nun innerhalb der Simulation ein Anstieg der CO2-Konzentration mit einem Rückgang der stomatären Leitfähigkeit verknüpft. Somit können Szenariosimulationen von veränderlichen Klimabedingungen zusammen mit erhöhten CO2-Konzentrationen und deren Auswirkungen auf die latenten Wärmeflüsse analysiert werden. Die Grünland- sowie auch die Agrarfläche zeigen verstärkte Evapotranspirationsraten unter erhöhten Temperatur- und CO2-Bedingungen, wohingegen der Waldstandort verminderte Evapotranspirationsraten zeigt. Hinsichtlich des CO2-Flusses reagieren alle drei berücksichtigten Landnutzungen mit erhöhten Aufnahmeraten von Kohlenstoff, wobei der Waldstandort den höchsten Anstieg aufweist. Schlussendlich ergaben die Szenariosimulationen bezüglich Evapotranspiration und CO2, dass die Unterschiede zwischen den Landnutzungen gegenüber denen des prognostizierten Klimawandels überwiegen.

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