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Chesterman, David Allan. "Microclimate of aspen forests." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq22585.pdf.
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Norberg, Peter. "Microclimate measurements in the built environment." Doctoral thesis, KTH, Built Environment, 1998. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2717.
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Surface moisture plays an important role in thedeterioration of building surfaces. The extent and duration ofsurface moisture is generally impossible to predictfrommeteorological data and consequently direct measurement ofthis quantity is essential,e.g. using the WETCORR method. Thismethod has been developed in Scandinaviaduring the past 25years. From the beginning it was intended for measurementsofinstantaneous atmospheric corrosion rates and TOW (time ofwetness) using corrodingelectrolytic cells. Over the past 15years the method has been extended tomeasurements of surfacemoisture and TOW on building materials in general. To thatend amodified measuring concept has gradually been developed,including an inertelectrolytic cell with electrodes of gold(Au). More recently, the method has also been applied tomeasurements of moisture content (MC) in various materialsusingmodifications of the traditional pin-type electrodes.
This thesis summarises various measurement projects thathave involved theWETCORR method during the past 10 years. Someprojects are entirely focused on the method as such, some aremore concerned with the interaction between themoisture sensorand the environment. In some cases attempts are made tocorrelate TOW with corrosion.
The limitations of the ISO 9223 standard for estimating TOW(RH>80%, T>0°C) isclearly illustrated. Theshortcomings of the ISO standard become evident in climateswith sub-zero temperatures, in environments with significantdeposition of pollutantsand salt, and in situations where theexchange of radiation between building surfaces and thesurrounding environment creates large temperature differenceswhich in turnmay either promote or inhibit condensation.
A generalised definition of TOW based on the conductivity ofthe surface electrolyterather than the thickness of themoisture film is proposed. The modified TOW is called time ofconduction or time of corrosion, (TOC). Strict measurement ofTOC requiresthe use of an inert electrolytic sensor andexcitation by AC or pulsed DC withreversing of the polarity.This is different from the present WETCORR technique.Theadoption of the TOC concept opens up the possibility ofdividing time into "wet" and"dry" periods. This is believed tofacilitate for the development of dose-responsefunctions basedon the real physical/chemical processes occurring on materialsurfacesrather than on a parametric approach.
The WETCORR technique has proven to be very useful also formeasurements of MCin wood, a measurement concept called INWOOD.The general principles andtheoretical considerations for woodmoisture measurements are reviewed, includingthe derivation ofsemi-empirical relationships describing the dependence ofresistivity on MC, temperature and dry density of wood. Thesame technique should be possible to use with almost any porousbuilding material.
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Jansson, Christer. "Urban microclimate and surface hydrometeorological processes." Doctoral thesis, KTH, Mark- och vattenteknik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3879.
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The urban near surface atmosphere is of great concern since it affects the climate to which an increasing amount of people are immediately exposed. This study investigated the microclimate in central Stockholm in terms of the thermal conditions in the 0-2.5 m air layer and the water and heat exchange processes at different types of surfaces found within the urban environment. The main objective was to improve our understanding of the urban small-scale climate system. The urban microclimate was measured in terms of vertical air temperature profiles along a horizontal transect running through a vegetated park and its built-up surroundings during three clear and relatively calm summer days. The results showed that the air temperature at 1.2 m height within the park was 0.5 to 1.5 K lower than in the surrounding city blocks, and that the thermal stratification was generally stable (increasing temperature with height) in the park and unstable (decreasing temperature with height) in the built-up areas. In addition, there were a few examples of temperature gradients orientated in different directions within the lowest 2.5 m air layer, indicating horizontal advection between the park and the built-up areas. Climate conditions simulated with a three-dimensional microclimate model agreed well with observations and the model was therefore assumed to provide reasonable representations of important climate processes such as surface-air energy exchange processes. However, there were some discrepancies between observations and simulations that are discussed in terms of differences in real and modelled heat storage processes and wind conditions. Processes that need to be included for a more precise model description of areas such as the Stockholm environment include dynamic heat storage in buildings and dynamic wind forcing during the course of the simulation. A soil-vegetation-atmosphere transfer model was used to study soil water transport, the surface energy balance of an asphalt surface, and the impact of urban climate on evapotranspiration. Based on model calibration to field measurements of soil water content in a till catchment outside Stockholm, new parameter values were estimated that can be used for water flow modelling of till soils. The heat fluxes of an asphalt surface were reliably simulated without knowledge of site-specific calibration and the model was useful in identifying problems with energy balance closure based on measurements only. Simulations of ‘urban’ modifications to the forcing climate conditions demonstrated that increased air temperature, and thereby increased vapour pressure deficit, had most effect on evapotranspiration from tall vegetation, while increased long-wave radiation raised grass evapotranspiration the most.QC 20100901
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Petrov, Ryan. "The microclimate of Australian cattle feedlots." University of Southern Queensland, Faculty of Engineering and Surveying, 2007. http://eprints.usq.edu.au/archive/00003191/.
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[Abstract]: The incidence of cattle heat stress is a significant production and welfare issue for the feedlot industry. It is hypothesised that the presence and physical nature of feedlots causes significant microclimatic variations compared to the external environment.In order to test this hypothesis, data was collected using a series of automatic weather stations located in the external environment surrounding two Australian feedlots. Comparison of this data with regional Bureau of Meteorology sites was undertaken to verify the quality of these ‘control’ sites. To determine the climate within the feedlot separate automatic weather stations were placed within the cattle pens at each site, with one station located in an unshaded pen and one directly under an artificial shade structure within an adjacent pen.This dissertation reports the collection and analyses of detailed climatic data from the surrounds and within the cattle pens of these two Australian feedlots. The project also sought to determine microclimatic differences within the feedlot pen area that may be caused by the presence of the shade structures.It was found that the presence of a feedlot does create significant microclimatic variations. Specifically, it was determined that the albedo values of the feedlot pen surface are significantly lower (ranging from 0.13 to 0.19) than those of the external feedlot environment (typically 0.15 to 0.25). This is a result of the surface changes arising from the establishment of clay based manure covered pens. Under wet conditions the differences in albedo values were further increased. It was found that the short wave radiation reflection from the external feedlot environment was 4% greater than that from the unshaded feedlot pen surfaces under dry conditions and 10% greater under wet conditions. The increased adsorption of solar radiation by the feedlot pen surface created ground temperatures that were on average 2 to 4°C warmer than those of the feedlot surrounds. The re-radiation of heat from the pen surface was found to create warmer air temperatures within the feedlot pens compared to the external environment, particularly overnight. Between the hours of 4am to 6am it was found that on average the air temperatures of the shaded and unshaded feedlot pens were 0.7°C and 0.5°C warmer than the external feedlot environment.It was found that feedlot pen infrastructure and cattle significantly reduce wind speeds under a height of 10 metres. The average 2 metre wind speeds of the external feedlot environments were found to be 29% and 9% higher than those recorded in the unshaded pens at the northern and southern feedlots respectively.Shade structures within feedlot pens were found to be effective in reducing incoming solar radiation with the galvanised sheeting reducing incoming solar radiation by 76% and the shade cloth providing a 72% reduction. These reductions provided both lower ground temperatures and a significant reduction in radiant heat loads under the shade. It was determined that the environment under shade structures was more humid compared to that of the unshaded pens with humidity levels recorded being 8 to 12% higher. Shade structures also restrict horizontal wind movement with the 2 metre wind speeds in the shaded pens being on average 11% and 0.5% lower than those recorded in the unshaded pens for the Queensland and NSW feedlots respectively.Research has shown that microclimatic variations such as increased air temperatures, increased humidity and restricted air movement can have an adverse effect on cattle health. It is concluded from this project that in order to mitigate these effects a number of feedlot design concepts be implemented, and management practices should be adopted. Maintaining minimal quantities of manure on the pen surface will provide lower ground temperatures, dryer pen conditions and inhibit the re-radiation of heat and evapotranspiration from the pen surface. Adequate air flow should be maintained by siting feedlots in areas of suitable topography, and designing feedlot infrastructure and shade structures to maximise air movement. Shade structures need to aim at providing dryer pen surfaces to minimise humidity levels. Incorporation of these recommendations into feedlot design and management will assist in optimising the feedlot microclimate.
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Hawkins, Edward. "Aphid movement and microclimate in winter." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339655.
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Pritchard, K. M. "Shelter, microclimate and heat loss from sheep." Thesis, University of Nottingham, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303960.
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Guiselini, Cristiane. "Microclima e produção de gérbera em ambientes protegidos com diferentes tipos de cobertura." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/11/11131/tde-20022003-163059/.
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O objetivo deste trabalho foi avaliar a influência de ambientes cobertos com filme de polietileno branco leitoso e diferentes malhas de sombreamento (Termo-refletora 50% e Preta 50%) nas seguintes variáveis ambientais: irradiância solar global, irradiância fotossinteticamente ativa, temperatura e umidade relativa do ar e evapotranspiração, e de seus respectivos microclimas no crescimento, no desenvolvimento e na qualidade da Gerbera jamesonii (Gérbera). O experimento foi realizado entre o outono e o inverno de 2002, junto à área experimental do Departamento de Ciências Exatas, da E.S.A. "Luiz de Queiroz", Universidade de São Paulo, em Piracicaba, SP. Foi instalado um ambiente protegido, sub-dividido em três partes iguais. Um dos ambientes era coberto apenas pelo plástico leitoso (T1), enquanto os outros dois possuíam, ainda, malhas de sombreamento, que foram instaladas internamente, à altura do pé direito, sendo um com malha termo-refletora (Alumitela) (T2) e outro com malha preta (T3), ambas com 50% de sombreamento, fabricadas pela Solpack Ltda. Os sensores foram instalados no centro de cada ambiente protegido (sub-divisão) e em uma estação meteorológica automatizada, a 100 m do experimento, para coleta dos dados meteorológicos externos. Os ambientes protegidos afetaram os elementos meteorológicos diminuindo a radiação solar, a umidade relativa do ar durante o período diurno e a evapotranspiração das planta de Gérbera e aumentando a temperatura do ar. As transmitâncias médias da radiação solar pelas coberturas (plástico leitoso, plástico leitoso + malha termo-refletora e plástico leitoso + malha preta) foram, respectivamente 23, 11 e 7%. As temperaturas médias diárias do ar dentro dos ambientes protegidos foram cerca de 6 o C maiores no ambiente coberto pelo plástico leitoso e 3 o C maiores nos ambientes cobertos pelo plástico leitoso associado às malhas de sombreamento quando comparadas as temperaturas externas. Os tipos de cobertura, em função do microclima proporcionado, afetaram o desenvolvimento das plantas de Gérbera. O crescimento foi mais rápido sob o plástico leitoso e mais lento sob o plástico leitoso + malha preta. As plantas de Gérbera cultivadas sob os ambientes protegidos cobertos pelo plástico leitoso e pelo plástico leitoso + malha termo-refletora atenderam às exigências quanto ao número de botões florais. Isso não ocorreu no ambiente sob o plástico leitoso + malha preta. Quanto a altura da haste, as plantas cultivadas em ambiente protegido não apresentou valores médios superiores ao mínimo exigido, de 10 cm. Os microclimas proporcionados pelas coberturas constituídas por plástico leitoso e plástico leitoso + termo-refletora promoveram condições adequadas para o cultivo da Gérbera, durante o período entre o outono e o inverno. No entanto não pode-se afirmar que tais condições sejam representativas para todas as estações do ano, recomendando-se estudos futuros comparando-se diferentes materiais de cobertura em diferentes épocas do ano, visando um melhor entendimento do microclima na produção comercial de Gérbera.The objective of this work was to evaluate the influence of white polyethylene as a greenhouse cover and its association with different shading screens (thermal screen and black screen) on the following environmental elements: incoming solar radiation (Qg), photosynthetically active radiation (PAR), temperature (T), relative humidity (RH) and evapotranspiration (ET) and also to evaluate the effects of the different microclimatic conditions on the growth, development and quality of Gerbera Jamesonii. The experiment was carried out between late Autumn and Winter of 2002 at the experimental area of the Exact Sciences Departament, Agricultural College "Luiz de Queiroz", at the University of São Paulo, in Piracicaba, State of São Paulo, Brazil. A greenhouse was installed, sub-divided into three parts. One of them was covered just with white polyethylene (T1), while the others had, yet, shading screens, that were installed within the greenhouse, being one covered with a thermal screen (Alumitela) (T2) and the other one with a black screen (T3), both with 50% of shading, manufactured by Solpack Ltda. The meteorological sensors were installed in the center of each sub-division of the greenhouse and an automatic weather station was located at 100m from the experimental area, to collect external meteorological data. The covers in the greenhouse affected the microclimate, decreasing Qg, PAR, RH and ET and increasing T. The average transmission of solar radiation by the covers (white polyethylene, white polyethylene + thermal screen and white polyethylene + black screen) were, respectively, 23, 11 and 7%. The mean daily air temperatures within the greenhouse were about 6 o C higher in the white polyethylene and 3 o C higher in the environments covered by white polyethylene associated with the shading screens in comparison to the external temperatures. The types of covers, forming different microclimates, affected the growth and development of Gerbera plants. The growth was faster under the white polyethylene and slower under the white polyethylene associated with black screen. The plants cultivated under the greenhouse covered with white polyethylene and with white polyethylene associated with thermal screen filled the requirements in relation to the number of flower buttons. However, the same was not observed in the environment covered with white polyethylene associated with black screen. About the stem size, all the cultivated plants under all environmental conditions not presented the minimum required value (10 cm). In general, the microclimate influenced by the different covers offered adequated conditions for the cultivation of Gerbera, during autumn and winter periods. However, it is not possible to be sure that these conditions are representative for the whole year stations, being recommended forward studies comparing different cover materials on different periods of the year, searching for a better comprehension of the microclimate influence on the commercial production of Gerbera.
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Branco, Kauberg Gomes Castelo. "Microclimas e áreas verdes na cidade de Fortaleza - CE." reponame:Repositório Institucional da UFC, 2014. http://www.repositorio.ufc.br/handle/riufc/20229.
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BRANCO, Kauberg Gomes Castelo. Microclimas e áreas verdes na cidade de Fortaleza - CE. 2014. 212 f. Dissertação (Mestrado em geografia)- Universidade Federal do Ceará, Fortaleza-CE, 2014.Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-10-14T12:25:25Z No. of bitstreams: 1 2014_dis_kgcbranco.pdf: 13706329 bytes, checksum: 8d9c275d19008e80eb37bb7a1aafd22f (MD5)
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With the consolidation of Fortaleza as a major urban center in the ninth century and XX, and with the creation of its metropolitan region in the 1970s, is observed intensification in urban density and therefore a disclosure of city environmental problems, including those related to urban climate . In this perspective it was proposed to investigate, following the methodology of the Urban Climate System of Monteiro (1976, 2003), the climate in intra-urban areas of Fortaleza, specifically the green spaces and surroundings, aiming to analyze the thermal contrasts these areas with the gifted environments of construction. Samples were collected on representative days of contrasting seasonal periods, as follows: Autumn (on 25 and 26 April 2013), winter (27 and 28 August 2013), and the dry season with intense winds and Finally, in days (21 and 22 November 2013). Through the methodology proposed by Bargos, 2010, categorizing, spatial in Public Areas Green and potentially public. The description of each green area of the city were also held. Consideration was also the green area per inhabitant Index (IAV), as territorial scale opted for Regional later cauculando She administered the distribution of green areas in the city as a whole. As a result, Fortaleza has somo result of Green Areas Mapping the total of 13.34 m² / h (Public green areas) and 1.88 m² / h (Green Area Public Potentially). We observed the variation in temperature significantly intra-urban environment in general. The inner points thermal amplitudes were lower than the external points, the latter being more warm in the four sample areas analyzed.
Com a consolidação de Fortaleza como importante núcleo urbano no século IX e XX, e com a criação de sua Região Metropolitana na década de 1970, é observada uma intensificação no adensamento urbano e consequentemente uma evidenciação dos problemas ambientais citadinos, inclusive aqueles ligados ao clima urbano. Nesta perspectiva foi proposto investigar, seguindo a metodologia do Sistema Clima Urbano de Monteiro (1976, 2003), o clima em áreas intra-urbanas de Fortaleza, mais especificamente os espaços verdes e adjacências, objetivando analisar os contrastes térmicos destas áreas com os ambientes dotados de construção. As coletas foram realizadas em dias representativos de períodos sazonais contrastantes, sendo eles: Outono (nos dias 25 e 26 de abril de 2013), inverno (27 e 28 de agosto de 2013), e o período seco com forte intensidade dos ventos e, por fim, nos dias (21 e 22 de Novembro de 2013). Por meio da metodologia proposta por Bargos, 2010, categorização, espacialização em Áreas Verdes Publicas e Potencialmente Públicas. A descrição de cada área verde da cidade também foram realizadas. Analisou-se ainda o Índice de área verde por Habitante (IAV), como escala territorial optou-se por Regional Administrava cauculando posteriormente a distribuição de áreas verdes na cidade como um todo. Como resultados, Fortaleza apresenta somo resultado do Mapeamento de Áreas verdes o total de 13,34 m²/h (áreas verdes Publicas) e de 1,88 m²/h (Área Verde Potencialmente Pública). Observou-se a variação das temperaturas de forma expressiva no ambiente intra-urbano de um modo geral. Nos pontos internos as amplitudes térmicas foram menores que os pontos externos, sendo estes últimos mostrando-se mais quentes nas quatro áreas amostrais analisadas.
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Aubach, Rene. "Design of a microclimate for improving thermal quality." Thesis, KTH, Energiteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-129211.
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Anbar, Serry Omar. "The microclimate of Mina Valley during Haj period." Thesis, University of East Anglia, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251496.
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Cho, Jong-Sook. "Urban microclimate modification through the use of vegetation." Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267198.
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Harwood, Thomas David. "Dynamic three-dimensional plant-microclimate simulation model 'Ecospace'." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/10946.
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Growing plants modify the microclimate within which they grow by altering their physical structure. Thus individuals affect the subsequent growth of both themselves and competing neighbours. It is important that this feedback be represented in a model of dynamic vegetation change. A flexible generalised model "Ecospace" is presented, which was designed to be applicable to all terrestrial vegetation. The model uses a three-dimensional grid of hexagonal tiles to represent space above and below ground. Each individual plant may occupy one or more tiles within the grid. Any number of individuals may occupy each tile until all space is filled. Microclimate, comprising solar radiation, wind and temperature, is calculated for each tile. Plant growth depends on the microclimate of occupied tiles. Three different plant functional groups are represented. The current model can represent an area of up to 50 m2 for low shrub vegetation. However, at present, computer run time and restricted memory limits the volume which can practically be simulated. There is no fundamental reason why these limits could not be overcome. Some model runs are presented for heather plants growing under different structural and climatic regimes. Since the model represents the feedback of vegetation structure on microclimate, it is suitable for studies of the impact of changing weather patterns on ecosystems.
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Shinzato, Paula. "O impacto da vegetação nos microclimas urbanos." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/16/16132/tde-26032010-160951/.
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O objeto desta pesquisa são os efeitos da vegetação nas condições microclimáticas urbanas, partindo-se da premissa que a presença da vegetação influencia o microclima do seu entorno imediato. A partir de diferentes formas de distribuição das áreas verdes na cidade e com o uso de espécies locais, o objetivo é quantificar a intensidade e a distribuição espacial dos efeitos microclimáticos da vegetação, principalmente as alterações de temperatura do ar e superficial no nível do pedestre, utilizando-se modelos de balanço de energia e ferramentas computacionais. Foram feitas simulações paramétricas no ENVI-met a fim de investigar o efeito da distribuição de áreas verdes (linear, grandes massas verdes concentradas ou pequenos agrupamentos distribuídos em diferentes distâncias) e por meio das medições de campo pode-se quantificar a importância da vegetação (gramíneas, arbustos e arbóreas) nos aspectos climáticos. Os resultados mostram que o efeito da vegetação é local e não ocorre uma influência significativa muito além dos limites das áreas verdes. Em relação à intensidade do efeito da vegetação, a diferença média entre as temperaturas do ar nas áreas verdes arborizadas e as ruas adjacentes é de 1.5ºC. Já o sombreamento pelas árvores de copa densa (LAI=10), mostrou diferenças médias de 23ºC, nas temperaturas superficiais do solo, embaixo da copa. Esse resultado indica que o uso das árvores é uma estratégia para amenizar o efeito de ilha de calor nas metrópoles, pois evita o aquecimento de materiais como asfalto e concreto e a liberação da radiação de onda longa acumulada durante a noite.The main purpose of this research is the effects of vegetation in urban microclimate conditions, under the premise that the presence of vegetation influences the microclimate and its surroundings. Considering different forms of green space distribution and using native species, it could quantify the intensity and spatial distribution for the microclimate effects by a vegetated area. The modifications of air temperature and the surface temperature at the level of the pedestrians were analyzed based on energy balance and computer models. Parametric simulations on ENVI-met were done to investigate the effect of green areas distribution (linear forms, large mass of vegetation and small groups of trees) and were compared with on-site measurement data. The simulation results showed the impact of urban vegetation for climatic aspects. The outputs indicated that the vegetation effect is local and do not have a significant influence beyond the limits of the green area. Regarding to the intensity of vegetation effect, the average difference between air temperature under the trees and above the streets is 1.5ºC. While the shadowing of a dense tree (LAI=10) showed an average difference of 23ºC for superficial temperatures between green spaces and the street. This result pointed out that green area is an important strategy to mitigate the heat island effect in city centers, as it can prevent asphalt and concrete from heating and releasing long wave radiation during night time.
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Mendonça, Augusto Hashimoto de. "Avaliação do efeito de borda sobre a vegetação do cerrado stricto sensu inserido em matriz de pastagem." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/18/18139/tde-12082010-141506/.
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O Cerrado é o bioma brasileiro que mais perdeu área para o agronegócio em anos recentes, verificando que a expansão da fronteira agrícola sobre o Cerrado provocou a pulverização dos remanescentes em fragmentos cada vez menores, imersos em matrizes de baixa similaridade, causando uma série de impactos negativos sobre o ecossistema natural. A fragmentação de habitats é considerada uma das mais graves ameaças à conservação da biodiversidade, com consequências ecológicas variáveis, intensificadas na faixa de transição entre matriz e fragmento. Os efeitos de borda são decorrentes de mudanças físicas e bióticas nas faixas marginais das ilhas de vegetação natural, que promovem modificações nas características microclimáticas, as quais conduzem a uma série de alterações importantes nas comunidades que compõem os ecossistemas. O objetivo deste estudo foi investigar a existência de efeito de borda e suas consequências sobre a comunidade vegetal do Cerrado stricto sensu. O estudo foi realizado em fragmento de Cerrado com área de 980,8 ha, localizado no município de Iaras, SP, cujo entorno foi ocupado por pastagem durante cerca de um século. Efetuou-se a caracterização estrutural e florística de diferentes estratos da vegetação em diferentes distâncias da borda (0, 10, 20, 40, 80 m) e coletaram-se dados microclimáticos na matriz (a 10 m de distância da borda) e no interior do fragmento, nas diferentes distâncias da borda e em duas estações do ano (seca e chuvosa). Investigou-se a existência de um possível gradiente de estrutura ou composição da vegetação relacionado com a distância da borda e com as variáveis microclimáticas. Os resultados obtidos mostraram não existir variações de microclima e de estrutura e composição do componente arbóreo e herbáceo-arbustivo em relação à distância da borda do fragmento. Embora independente do microclima e, portanto, diferente dos clássicos efeitos de borda, a invasão pela braquiária (Urochloa decumbens) foi detectada como a única consequência da exposição da periferia do Cerrado stricto sensu às pressões da matriz, causando exclusão das gramíneas nativas e inibindo o desenvolvimento de plantas lenhosas de pequeno porte. A ausência de efeito de borda sobre os demais componentes da vegetação sugere, em um primeiro momento, que esta não é uma ameaça importante para a conservação do cerrado. Porém, a invasão biológica pela gramínea africana é relativamente recente (foi introduzida há cerca de três décadas na propriedade) e suas consequências ainda não podem ser avaliadas adequadamente. É possível que seus impactos sobre os estratos superiores da vegetação venham a ser observados no futuro, quando a inibição da regeneração das espécies arbustivas e arbóreas comprometer a dinâmica da comunidade vegetal e a substituição dos adultos nas populações dessas espécies. Além disso, hoje a invasão só causa impactos significativos sobre a faixa de 0 a 20 m de distância da borda, mas não é possível prever se a gramínea invasora vai se expandir rumo ao núcleo do fragmento no futuro.From the Brazilian biomes, the Cerrado has been the most widely and rapidly converted to agribusiness in recent years. The expansion of agricultural frontier over the Cerrado domain resulted in thousands of small fragments embedded in matrices of low similarity, causing a series of negative impacts on the natural ecosystem. Habitat fragmentation is considered one of the most serious threats to the conservation of biodiversity and ecological consequences vary, being intensified in the range of transition between matrix and fragment. The edge effects are caused by biotic and physical changes in marginal areas of the islands of natural vegetation, promoting changes in microclimatic characteristics, which leads to a series of important changes in the ecosystems. The aim of this study was to investigate the existence of edge effect and their consequences on the plant community of Cerrado sensu stricto. The study was conducted in Cerrado fragment with an area of 980.8 ha, located in the municipality of Iaras, SP, whose surrounding area was occupied by pasture for about a century. Structure and floristic composition of distinct vegetation layers was assessed at different distances from the edge (0, 10, 20, 40 and 80 m). Climatic data were collected in two seasons (dry and wet), at the same distances withing the fragment and also in the matrix (10 m away from the edge). The existence of a gradient of vegetation composition or structure and the microclimatic variables related to distance from the edge was investigated. No changes in microclimate and structure or composition of the wood layers related to distance from the edge was observed. Although independent of the microclimate and therefore different from classic edge effects, invasion by the African grass Urochloa decumbens (braquiária) was detected as the only consequence of exposure of the periphery of the cerrado sensu stricto to the pressures of the matrix, causing the exclusion of native grasses and inhibiting the development of small woody plants. The absence of edge effect on other components of the vegetation suggests, at first, that this is not a major threat to the conservation of the Cerrado. However, the biological invasion by the African grass is relatively recent (it was locally introduced about three decades ago) and its consequences have not been adequately assessed. It is possible that their impacts on the upper strata of the vegetation may be observed in future, when the inhibition of regeneration of shrub and tree species jeopardize the dynamics of plant community and the replacement of adults in the populations of these species. In addition, at present the invasion has significant impacts only over 0-20 m from the edge, but it is impossible to predict whether the invasive grass will expand or not into the core area of the fragment in the future.
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Branco, Kauberg Gomes Castelo. "Microclimas e Ãreas verdes na cidade de Fortaleza - CE." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14828.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoCom a consolidaÃÃo de Fortaleza como importante nÃcleo urbano no sÃculo IX e XX, e com a criaÃÃo de sua RegiÃo Metropolitana na dÃcada de 1970, Ã observada uma intensificaÃÃo no adensamento urbano e consequentemente uma evidenciaÃÃo dos problemas ambientais citadinos, inclusive aqueles ligados ao clima urbano. Nesta perspectiva foi proposto investigar, seguindo a metodologia do Sistema Clima Urbano de Monteiro (1976, 2003), o clima em Ãreas intra-urbanas de Fortaleza, mais especificamente os espaÃos verdes e adjacÃncias, objetivando analisar os contrastes tÃrmicos destas Ãreas com os ambientes dotados de construÃÃo. As coletas foram realizadas em dias representativos de perÃodos sazonais contrastantes, sendo eles: Outono (nos dias 25 e 26 de abril de 2013), inverno (27 e 28 de agosto de 2013), e o perÃodo seco com forte intensidade dos ventos e, por fim, nos dias (21 e 22 de Novembro de 2013). Por meio da metodologia proposta por Bargos, 2010, categorizaÃÃo, espacializaÃÃo em Ãreas Verdes Publicas e Potencialmente PÃblicas. A descriÃÃo de cada Ãrea verde da cidade tambÃm foram realizadas. Analisou-se ainda o Ãndice de Ãrea verde por Habitante (IAV), como escala territorial optou-se por Regional Administrava cauculando posteriormente a distribuiÃÃo de Ãreas verdes na cidade como um todo. Como resultados, Fortaleza apresenta somo resultado do Mapeamento de Ãreas verdes o total de 13,34 mÂ/h (Ãreas verdes Publicas) e de 1,88 mÂ/h (Ãrea Verde Potencialmente PÃblica). Observou-se a variaÃÃo das temperaturas de forma expressiva no ambiente intra-urbano de um modo geral. Nos pontos internos as amplitudes tÃrmicas foram menores que os pontos externos, sendo estes Ãltimos mostrando-se mais quentes nas quatro Ãreas amostrais analisadas.
With the consolidation of Fortaleza as a major urban center in the ninth century and XX, and with the creation of its metropolitan region in the 1970s, is observed intensification in urban density and therefore a disclosure of city environmental problems, including those related to urban climate . In this perspective it was proposed to investigate, following the methodology of the Urban Climate System of Monteiro (1976, 2003), the climate in intra-urban areas of Fortaleza, specifically the green spaces and surroundings, aiming to analyze the thermal contrasts these areas with the gifted environments of construction. Samples were collected on representative days of contrasting seasonal periods, as follows: Autumn (on 25 and 26 April 2013), winter (27 and 28 August 2013), and the dry season with intense winds and Finally, in days (21 and 22 November 2013). Through the methodology proposed by Bargos, 2010, categorizing, spatial in Public Areas Green and potentially public. The description of each green area of the city were also held. Consideration was also the green area per inhabitant Index (IAV), as territorial scale opted for Regional later cauculando She administered the distribution of green areas in the city as a whole. As a result, Fortaleza has somo result of Green Areas Mapping the total of 13.34 m / h (Public green areas) and 1.88 m / h (Green Area Public Potentially). We observed the variation in temperature significantly intra-urban environment in general. The inner points thermal amplitudes were lower than the external points, the latter being more warm in the four sample areas analyzed.
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Shinzato, Paula. "Impacto da vegetação nos microclimas urbanos em função das interações solo-vegetação-atmosfera." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/16/16132/tde-12092014-115829/.
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Este trabalho tem por objetivo quantificar o impacto da vegetação nos microclimas urbanos abaixo do dossel, em função das interações solo-vegetação-atmosfera. Essas interações consideram os efeitos: 1) do dossel propriamente dito, expressos pelas variáveis índice de área foliar - IAF (Leaf Area Index - LAI) e distribuição geométrica das aberturas na copa (gap fraction); 2) da cobertura do solo, expressa pela composição do solo, sua temperatura e teor de umidade, e 3) das variáveis microclimáticas locais (temperatura do ar, umidade do ar, radiação solar, temperatura radiante media, temperatura superficial, direção e velocidade dos ventos). Considerando-se que o impacto da vegetação nos microclimas urbanos é função das interações solo-vegetação-atmosfera, e tendo em vista resultados de estudos anteriores, a hipótese deste trabalho é que, para o clima de São Paulo, em função dos processos de evapotranspiração e do sombreamento, a redução na temperatura do ar abaixo do dossel em parques urbanos será de cerca de 1o C e a redução da temperatura superficial será de cerca de 20oC, ambas em relação às áreas não sombreadas pela vegetação, e que esses efeitos limitam-se à borda do parque sob condições de baixa velocidade do vento, de cerca de 1 m/s. O método é 1) indutivo, por meio de medições de campo durante o período de dias quentes e frios no Parque Tenente Siqueira Campos (Trianon), na cidade de São Paulo, para o registro de dados microclimáticos e para o levantamento das variáveis do dossel e do solo; e 2) dedutivo, com a calibração entre dados medidos e simulados pelo modelo ENVI-met 3.1 Beta 5 e a simulação de diferentes cenários, variando-se as características do dossel. Para se estimar a densidade foliar média das copas foram adotados dois métodos não-destrutivos indiretos: a medição do IAF com o equipamento LAI-2000 (LI-COR) e a análise das fotos hemisféricas, utilizando-se o aplicativo Can-Eye. De acordo com os resultados das simulações, variando-se as caraterísticas do dossel, verificou-se uma redução máxima de 1ºC na temperatura do ar e de 19°C na temperatura superficial, ao se comparar os valores obtidos abaixo de uma copa densa (forma elíptica e IAF 5m2/m2) em relação às condições do entorno, fora do parque. Esse efeito se estende por, no máximo, 5m de distância a partir dos limites do parque, com velocidade do ar de 1m/s e umidade de 40% na camada superficial do solo (0-20cm). Foi feita a aplicação do TEP - Temperatura Equivalente Percebida e verificou-se que a redução de 1°C na temperatura do ar pode representar de 3°C a 5°C no conforto térmico das pessoas. Esses resultados comprovam a hipótese inicial e mostram não apenas a importância do tipo de vegetação escolhida (formato da copa, IAF e distribuição geométrica das aberturas na copa) como as características do meio em que ela está inserida (condições microclimáticas locais e de solo). Os resultados podem contribuir para a formulação de políticas públicas visando à mitigação dos efeitos de aquecimento urbano, particularmente diurnos, em climas tropicais.The objective of this work is to quantify the impact of vegetation on urban microclimates, under the canopy, due to soil-vegetation-atmosphere interactions. It considers the following effects: 1) the canopy itself, expressed by the variable leaf area index - LAI and the geometric openness distribution in the canopy (gap fraction); 2) the soil coverage, expressed by soil composition, soil temperature and soil humidity, and 3) the local microclimatic variables (air temperature, humidity, solar radiation, mean radiant temperature, surface temperature, wind direction and wind speed). Considering the impact of vegetation on urban microclimates as a function of soil-vegetation-atmosphere, and based on the outcomes of preview studies, this work starts from the hypothesis that for São Paulo climate and as a result of evapotranspiration and shadowing process, the reduction of air temperature under the canopy will be between 1°C to 2°C and for surface temperature, it will be around 20°C, both in relation to an area without tree shadowing. These effects are restricted to the borders of the park, especially under the conditions of low wind speed, approximately 1m/s. The methods are: 1) inductive, based on field measurements in summer and winter at Tenente Siqueira Campos Park (Trianon Park), in the city of São Paulo, registering microclimatic data and collecting information for canopy and soil; and 2) deductive, with the calibration of measured and simulated data by ENVI-met 3.1 Beta 5 and the simulation for different scenarios varying the canopy characteristics. To estimate the average leaf density for trees canopy two no-destructive indirect methods were applied: measurement of LAI using the equipment LAI-2000 (LI-COR) and the analysis of hemispheric photographs, using a software application Can-Eye. According to the simulation results, for different characteristics for canopy, it could be verified a maximum reduction of 1ºC in air temperature and 19°C for surface temperature, when comparing the obtained value under a dense canopy (elliptical form and LAI of 5m2/m2) to the conditions on the street. The maximum extension of these effects were up to 5m from the limits of the park, considering 1m/s for wind speed and 40% for soil humidity in the upper layer (0-20cm). The thermal index TEP calculated and it could be seen that the reduction of 1°C for air temperature can represent from 3°C to 5°C in terms of thermal comfort of people. By these results, the initial hypothesis has proven to be correct and showed not only the importance of the type of vegetation selected (canopy form, LAI values and geometric distribution of canopy openness) but also the characteristics of the surrounding environment (microclimatic and soil conditions). Furthermore, it will contribute to formulate public politics aiming to mitigate urban warming effect, mainly during daytime, in tropical cities.
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Simon, Helge [Verfasser]. "Modeling urban microclimate : development, implementation and evaluation of new and improved calculation methods for the urban microclimate model ENVI-met / Helge Simon." Mainz : Universitätsbibliothek Mainz, 2016. http://d-nb.info/1102563188/34.
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Bulow, Anna Elisabeth. "Preventive conservation for paper-based collections within historic buildings." Thesis, De Montfort University, 2002. http://hdl.handle.net/2086/4313.
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Previous research has been carried out concerning the conservation of both historic buildings and library and archive collections. Little work has, however, been undertaken to look at the interface between the two. The following research has been carried out in the context of an interdisciplinary project linking key disciplines in an examination of the issues relating to conservation problems in historic buildings used for library and archive purposes. This thesis presents a comprehensive literature review, evaluating published data on both the preservation of paper-based collections in libraries and archives, and preventive conservation of historic buildings and monuments. Emphasis is given to the interface between the two. Furthermore, a survey of British archives and libraries has been carried out, including the evaluation of questionnaire and site data. The survey focuses on preventive conservation measures as well as past and present problems of dampness. This survey proved problems with dampness to be often misdiagnosed and the consequences of damage underestimated. From the surveyed collections, two case studies have been selected for environmental monitoring in order to investigate macro- and micro-climates under different environmental conditions. Resulting data suggest that the micro-environment of a confined space is influenced by the amount of paper housed within it. This has assisted in explaining the interaction between paper and the immediate environment. At the same time, data has confirmed that the overall surface area of paper available for environmental interaction is more important than paper type or book size, with respect to the overall conditions within the storage space. Although degradation mechanisms of paper with respect to cycling conditions are not entirely clear, results of this study emphasise the importance of ventilation and dehumidification in order to avoid mould germination and/or growth. The data have been used to determine whether the internal environment of enclosed bookcases, and hence the immediate environment of the collection, can be adequately predicted from ambient data taken within the room. Mathematical models have been developed for both metal and wooden bookcases, and have shown that even when the ambient conditions are unstable, the relationship between ambient RH and the RH inside a book in an enclosed bookcase can be predicted within a 5% margin (1% for a stable environment).
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Haskin, Catherine Marie. "Nitrogen availability and soil microclimate after clearcutting lodgepole pine." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24677.
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Long term management of lodgepole pine depends, in part, on the nutrient capital of the site. Harvesting has been shown to increase the availability of nitrogen and other nutrients for a limited period of time. This increase, or nutrient flush, following cutting has been attributed to several factors including changes in organic matter quantity and quality, soil moisture and temperature regimes, and competition for nutrients. Knowledge of the duration and the magnitude of the nutrient flush would be valuable for management decisions.
A consequence of lodgepole pine clearcuts was studied for soil nitrogen availability and microclimate. Mineral soil and forest floor samples were anaerobically incubated and analyzed for ammonium-nitrogen (ppm). The mineral soil showed a flush lasting about 12 years, peaking by year 8, while the forest floor material showed no trend. The size of the increase from year 2 to year 8 was about 52%. Temperature (air and soil), soil moisture, solar radiation, and precipitation data were collected, and a soil water budget was calculated using a simple water balance model. The average calculated soil water deficit was 119 mm, but this may have been an over-estimate.
Windrowing following cutting may have depleted the site nitrogen reserve which in turn reduced the amount that was mineralized during incubation. The interaction between the soil temperature and moisture may have further limited nitrogen availability to the lodgepole pine trees.
It is concluded that the dynamics of nitrogen availability following clearcutting are important for the establishment and growth of lodgepole pine. The summer moisture deficit appears to limit the nitrogen mineralization rate as well as seedling growth.Forestry, Faculty of
Graduate
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Kuehl, Petra. "Vegetation, soil and microclimate in the post-industrial landscape." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ47338.pdf.
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Worthington, Andrew Gerald. "Mathematical modelling of the microclimate in open-top chambers." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308309.
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Corlett, Janet E. "Leucaena/millet alley cropping in India : microclimate and productivity." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328810.
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Luker-Brown, M. "Simulating the interactions between canopy microclimate and vegetation physiology." Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299539.
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Mao, Jiachen. "Automatic calibration of an urban microclimate model under uncertainty." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120873.
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Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2018.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 79-86).
Simulation models play an important role in the design, analysis, and optimization of modern energy and environmental systems at building or urban scale. However, due to the extreme complexity of built environments and the sheer number of interacting parameters, it is difficult to obtain an accurate representation of real-world systems. Thus, model calibration and uncertainty analysis hold a particular interest, and it is necessary to evaluate to what degree simulation models are imperfect before implementing them during the decision-making process. In contrast to the extensive literature on the calibration of building performance models, little has been reported on how to automatically calibrate physics-based urban microclimate models. This thesis illustrates a general methodology for automatic model calibration and, for the first time, applies it to an urban microclimate system. The study builds upon the previously reported and updated Urban Weather Generator (UWG) to present a deep look into an existing urban district area in downtown Abu Dhabi (UAE) during 2017. Based on 30 candidate inputs covering the meteorological factors, urban characteristics, vegetation variables, and building systems, we performed global sensitivity analysis, Monte Carlo filtering, and optimization-aided calibration on the UWG model. In particular, an online hyper-heuristic evolutionary algorithm (EA) is proposed and developed to accelerate the calibration process. The UWG is a fairly robust simulator to approximate the urban thermal behavior for dierent seasons. The validation results show that, in single-objective optimization, the online hyper-heuristics can robustly help EA produce quality solutions with smaller uncertainties at much less computational cost. Finally, the resulting calibrated solutions are able to capture weekly-average and hourly diurnal profiles of the urban outdoor air temperature similar to the measurements for certain periods of the year.
by Jiachen Mao.
S.M. in Building Technology
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Stetten, George, Fred Koontz, Christine Sheppard, and Charles Koontz. "TELEMETRIC EGG FOR MONITORING NEST MICROCLIMATE OF ENDANGERED BIRDS." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613481.
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International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, NevadaA series of artificial eggs has been developed for the New York Zoological Society to measure conditions in the nest of the white-naped crane (Grus Vipio). Investigations undertaken at the Bronx Zoo have endeavored to improve artificial incubation of the eggs of endangered species of birds. Artificial eggs were constructed and camouflaged so that a pair of birds would accept and incubate them. Inside each counterfeit egg, a radio telemetry transmitter was hidden to report on the temperature and humidity in the nest and the orientation of the egg itself with respect to gravity.
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Kutta, Evan. "Quantifying microclimate heterogeneity within a contemporary plant growth facility." Thesis, University of Missouri - Columbia, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10157317.
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Three separate contemporary climate controlled greenhouse rooms in the Sears Plant Growth Facility located at the University of Missouri, Columbia, MO, USA were selected for microclimate analysis. Temperature, relative humidity, and incoming solar radiation data were logged hourly between 5/9/12 and 9/5/12 to test the efficacy of current management practices and to improve understanding of the spatial and temporal climate variability inside the greenhouse rooms. The average horizontal temperature gradient was 0.08 °C×m -1 and the maximum horizontal temperature gradient was 0.83 ºC×m -1. The average vertical temperature gradient was 2.27 °C×m -1 and the maximum lapse rate was 11.65 °C×m-1. Vapor pressure deficit (VPD) calculations were made using data as a proxy to assess plant physiological response to internal conditions. The average horizontal VPD gradient was 0.025 kPam-1 and the maximum VPD gradient was 0.350 kPa×m-1. Collectively, results indicate a heterogenous distribution of temperature and vapor pressure deficit created primarily by the active cooling system. Several recommendations are supplied to improve the homogeneity of the internal greenhouse climate, which will lead to increased productivity and profits for greenhouse managers.
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Yang, Xiusheng. "Greenhouse microclimate : transport processes, plant responses and dynamic modeling." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1145370914.
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Ward, Sarah. "Microclimate and Phenology at the H.J. Andrews Experimental Forest." Thesis, University of Oregon, 2018. http://hdl.handle.net/1794/23916.
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Spring plant phenology is often used as an indicator of a community response to climate change. Remote data and low-resolution climate models are typically used to predict phenology across a landscape; however, this tends to miss the nuances of microclimate, especially in a mountainous area with heterogeneous topography. I investigated how inter-annual variability in regional climate affects the distribution of microclimates (i.e., areas <100m2) and spring plant phenology across a 6400-hectare watershed within the Western Cascades in Oregon. Additionally, I created species-specific models of bud break at the microclimate scale, that could then be applied across a wider landscape. I found that years with warm winters, few storms and low snowpack have a homogenizing effect on microclimate and spring phenology events, and that bud break models developed at a local scale can be effectively applied across a broader landscape.
This thesis includes previously unpublished coauthored material.
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Julia, Cécile. "Thermal stresses and spikelet sterility in rice : sensitive phases and role of microclimate." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20192/document.
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Les inflorescences de riz sont sensibles au froid et à la chaleur ce qui se traduit par une stérilité des épillets à floraison. Ce n'est cependant pas directement la température de l'air qui est en cause mais la température des tissus à des stades de développement précis. Les stratégies pour faire face au stress thermique sont : 1) la tolérance physiologique d'une variété particulière; 2) l'échappement temporel au stress par l'ajustement de la phénologie et de l'heure de l'anthèse (TOA); 3) l'évitement du stress par le microclimat généré par la culture. Cette thèse a pour but de caractériser l'effet des composantes climatiques sur 2) et 3), et pour ce, le même essai a été mené au champ sur quatre variétés de riz irrigué cultivées dans quatre environnements climatiques contrastés (Philippines, 2 saisons aux Sénégal, France). Bien que peu de différences variétales aient été observées au sein de chaque site, il existe une grande variabilité de l'heure de l'anthèse et de la différence de température (TD) entre panicule (Tp) et air (Tair) en réponse à l'environnement. La durée de l'anthèse est stable et limitée à environ 2 heures par jour, alors que l'heure de l'anthèse varie de 3.4 à 6.75 heure solaire. Au moment de l'anthèse, TD observée varie entre +2 et -9.5°C. TOA et TD sont principalement caractérisés par Tair et VPD (Vapour Pressure Deficit) observés antérieurement (TOA) ou pendant (TD) l'anthèse. De plus, il existe une corrélation significative entre la stérilité (chaud ou froid) observée à maturité et Tp aux stades sensibles. Ces résultats montrent qu'en termes de risque de stérilité paniculaire pour le riz irrigué à floraison, un climat moyennement chaud et humide est plus dangereux qu'un climat très chaud mais sec car un fort VPD favorise la transpiration de la canopée et des panicules. TOA et TD ont ensuite été intégrés au modèle de culture RIDEV V.2 (qui prédit la stérilité) et les simulations de TD ont été comparées aux résultats d'un autre modèle de Tp (IM2PACT) développé indépendamment au Japon. Ces deux modèles s'avèrent robustes, et de futures collaborations mèneront à une validation complète de chaque modèle voire une intégration de ceux-ci à un nouvel outil en vues d'étudier l'impact des changements climatiques sur les cultures.Les résultats de cette étude permettront dans un futur proche 1) d'aider les sélectionneurs en apportant de nouveaux traits d'intérêts, et 2) de définir un zonage des territoires à haut risque de stress thermique pour le riz irrigué, pour des scénarios climatiques actuels et anticipés. Des études complémentaires seront nécessaires pour permettre l'application de cette approche aux systèmes non irriguésAt the reproductive stage, rice spikelets are sensitive to cold and to heat which can lead to spikelet sterility. However, it is not the air temperature but the temperature of the sensitive organ itself during some specific sensitive stages that is involved. There are three different strategies to cope with thermal stress: 1) physiological tolerance of a particular variety; 2) temporal escape of the stress thanks to phenology and time of day of anthesis (TOA) adjustments; 3) stress avoidance through microclimate generated by crop architecture and transpiration. This PhD aims to characterize the effect of environment on 2) and 3) and to attain this goal, the same experiment was conducted with four rice varieties irrigated and grown in four different climatic environments (Philippines, Senegal two seasons, France). Even though few varietal differences were observed within a site, a great variability of TOA and difference of temperature (TD) between panicle (Tp) and air (Tair) exists in response to the environment. Anthesis duration is stable and limited to 2 hours per day, whereas time of onset of anthesis varied between 3.4 to 6.75 hours after sunrise. During anthesis, observed TD varied between +2.5 and -9.5°C. TOA and TD are mostly explained with Tair and VPD (Vapour Pressure Deficit) observed before (TOA) or during (TD) anthesis. A significant correlation between spikelet sterility (due to cold or heat) and Tp at sensitive stages was established across sites and varieties. Those results showed that for irrigated rice, humid and moderately hot environments are more subject to heat stress sterility than very hot but dry environments, because panicle and canopy transpiration are favored by high VPD. Ultimately, RIDEV V.2 crop model (predicting spikelet sterility) was developed to integrate the previous results and Tp simulations were compared to another Tp model (IM2PACT) simulations, developed independently with a different approach in Japan. Those two models are robust and future collaborations will lead to complete model validations and maybe integration in a new modeling tool to answer the need in evaluating the impact of different climate change scenarios and the adaptation of crop response to those changes.In a short term, the results of this study will enable to 1) help breeders providing them new interest traits for thermal tolerance, and 2) define geographic zoning for high heat stress risk for irrigated rice, for present and future climate change scenarios. Complementary studies are needed to apply this approach to non irrigated system
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Martin-Chave, Ambroise. "Facteurs de régulation naturelle des bio-agresseurs par les cortèges de prédateurs généralistes : effets microclimatiques dans un système maraîcher agroforestier biologique." Thesis, Avignon, 2018. http://www.theses.fr/2018AVIG0697/document.
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L’agroforesterie, et plus particulièrement les systèmes sylvo-arables, sont des systèmes peu étudiés qui présentent des intérêts agronomiques et environnementaux en systèmes tempérés. Les systèmes agroforestiers pourraient notamment fournir un microclimat favorable aux cultures maraîchères conduites en agriculture biologique en contexte pédoclimatique méditerranéen. Cependant, il existe encore peu de références scientifiques sur le sujet, et l’issue des interactions entre arbres et cultures sont encore me connues. En particulier, le microclimat généré par des arbres âgés est susceptible de modifier les relations entre cultures, bio agresseurs et pré dateurs généralistes, qui peuvent conditionner la performance d’une association agroforestière. Cette thèse avait donc comme objectifs :➢ D’évaluer l’impact de l’ouverture de la canopée sur la biodiversité et l’activité densite des coléoptères carabiques.➢ D’identifier comment le microclimat peut influencer les processus de régulation naturelle.Les systèmes agroforestiers se développent sur des temps longs (pluriannuels): l’étude s’est focalisée sur un système ayant déjà des arbres âgés de 20 ans pour en étudier l’impact sur le microclimat et la faune du sol. Pour faire varier ce microclimat, un gradient d’ouverture de la canopée a été réalisé. La température de l’air ambiant, l’hygrométrie et le pourcentage d’ouverture du milieu ont ensuite été mesurés.En premier lieu, la faune du sol a été échantillonnée durant 2 ans (non révolus), et les structures des communautés de Carabidae ont été analysées d’un point de vue taxonomique et fonctionnelle, au moyen de 5 traits écologiques. Les résultats montrent que la structure taxonomique est peu affectée, mais qu’à la fois l’activité-densité spécifique des espèces et les traits fonctionnels sont modifiés par le gradient d’ouverture du milieu. En particulier, la fermeture de la canopée du système agroforestier favorise les espèces ayant une affinité pour des milieux fermés et humides.L’activité journalière de deux prédateurs abondants a été caractérisée dans une période estivale chaude (juillet), et plus douce (septembre). Les résultats montrent qu’à la fois la saison mais également l’ouverture de la canopée peuvent modifier les rythmes journaliers de l’Arachnidae et du Carabidae les plus abondants à cette période (Pardosa hortensis, Pseudoophonus rufipes).Dans un troisième temps, le travail s’est focalisé sur le potentiel de prédation des prédateurs de la faune du sol, au moyen de cartes sentinelles de prédation à deux périodes estivales, juin et aout. Les résultats montrent que sur au moins une période, le potentiel de prédation sur larves de lépidoptères (Cydia pomonella) est différent entre les traitements. Ces différences sont probablement corrélées aux différences d’activité-densité et aux différences microclimatiques induites par les différences de couverts arborés.Dans un dernier temps, l’étude s’est focalisée sur une culture, la salade, et les dégâts causés par les limaces dans les différents traitements, sur les feuilles visibles. Plus de dégâts sous les arbres ont été constatés, malgré une activité-densité d’Arion lusitanicus et de Deroceras reticulatum non supérieures au témoin au mois de juin où les dégâts ont fortement augmenté. Les méthodes utilisées (planches, pots pièges neutres et attractifs) ont présenté des efficacités différentes, dont l’intérêt respectif est discutéAgroforestry, and more specifically sylvo-arable systems, are poorly studied systems with agronomic and environmental interests in temperate systems. They could provide a favorable microclimate for vegetable crops grown in organic agriculture in Mediterranean pedoclimatic context. However, there are still few scientific references on the subject, and the outcome of the interactions between trees and cultures are still unknown. The microclimate generated by old trees is likely to alter the relations between crops, pests and generalist predators, which can condition the performance of an agroforestry system.This thesis had two main objectives:• To evaluate the impact of canopy openness on ground beetle diversity and activity-density• Identify how the microclimate can influence natural regulation processes.Agroforestry systems develop over long periods (pluriannual): the study focused on a system already having 20-year-old trees to study the impact on microclimate and soil fauna. To modulate this microclimate, a canopy opening gradient has been realized. The ambient air temperature, the hygrometry and the percentage of canopy aperture were then measured.First, the soil fauna was sampled for 2 years and the structure of the Carabidae communities was analyzed from a taxonomic and functional point of view, using 5 ecological traits. The results show that the taxonomic structure is poorly affected, but that both species specific activity-density and functional traits are modified by the canopy openness, which favored species with affinity for closed and moist environments.The diel activity of two abundant predators was characterized in a hot summer period (July), and cooler (September). The results show that both the season and the opening of the canopy can modify the daily rhythms of the most abundant Arachnidae and Carabidae (Pardosa hortensis, Pseudoophonus rufipes).Thirdly, the work focused on the predation potential of predators of soil fauna, using sentinel preys method at two periods, (June and August). The results show that for at least one period, the predation potential on Lepidoptera larvae (Cydia pomonella) was different between treatments. These differences are probably correlated with differences in activity-density and microclimatic differences induced by the differences in canopy treatmentLastly, the study focused on lettuce crops and the damage caused by slugs in the different treatments, on the visible leaves. More damage under the trees was observed, despite a similar activity- density of Arion lusitanicus and Deroceras reticulatum compared to control in June, where the damage increased significantly. The methods used (boards, neutral traps and attractive traps) presented different efficiencies, whose respective interest is discussed
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Hardwick, Stephen Robert. "Interactions between vegetation and microclimate in a heterogeneous tropical landscape." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/52780.
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Land use change and forest fragmentation threaten biodiversity in the tropics. One important mechanism by which species are affected by land use change is the change in microclimate that occurs with modifications to the vegetation cover. We quantified the link between vegetation and microclimate in the tropics for the first time, finding strong relationships between leaf area index and five key microclimate variables. The mean daily maximum air temperature 1.5 m above the ground was up to 6.5 °C hotter in oil palm plantations and up to 2.5 °C hotter in logged forest than in primary forest, which could have large impacts on the organisms living in these habitats. We also developed a process based microclimate model designed for use across this range of land use types. The model reproduced the direction of the observed trends, and performed well in predicting mean climate variables as well as inter- and intraday variability. Model results suggested that changes in canopy height associated with logging and agricultural conversion have a more important influence on the near-surface microclimate than changes in leaf area index. The hotter, drier and windier microclimate found near a forest edge could drive an increase in tree transpiration. For the first time, transpiration rates were measured in six trees before and immediately after the creation of a forest edge by monitoring sap flow. After edge creation, mean daily sap flow rates increased in all trees, with the increases ranging from 4-61%. The magnitude of the change in mean daily sap flow was found to be positively correlated with diameter at breast height and negatively correlated with the distance to the forest edge. These increases in tree water use near forest edges, particularly by large trees, could create water shortages and drive increased tree mortality.
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Sánchez, Luis Alberto. "Bud microclimate, carbohydrate status, and fruitfulness in Vitis vinifera L. /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.
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Gillingham, Phillipa. "The relative importance of microclimate and land use to biodiversity." Thesis, University of York, 2010. http://etheses.whiterose.ac.uk/1210/.
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The extent of species' distributions, and their abundance within them, can be affected by many factors. At coarse resolutions and large spatial extents, climatic variables are often found to be important in determining the boundaries of species' ranges. However, several authors have postulated that variables such as land cover or species interactions are more important in determining where species will be found at finer resolutions within a landscape. Climatic variables are often not available at the fine resolutions necessary to test this hypothesis. In this study, I first show that topography is important in influencing the temperature that will be experienced at a particular location. Temperatures generally decrease with elevation (known as the lapse rate). However, extremes of temperature, such as absolute maxima and minima, can also be influenced by the angle and aspect of a slope. Whilst high resolution elevation data are occasionally included in climatic models of species' distributions, the effects of slope and aspect have so far been ignored. My second data chapter uses all three topographical variables (elevation, slope and aspect) to interpolate temperatures for three landscapes. These interpolated temperatures, along with land cover variables and an index of soil moisture, are included in exploratory analyses which suggest that microclimate is at least as important as land cover in determining spatial patterns of abundance for 20 species of ground beetle. Given this potential importance of microclimate in determining where species will be found at fine resolutions, I then show that different resolution data layers generate different predictions about the amount of a landscape that will remain suitable following climatic warming. Fine resolution layers predict a slower loss of thermally suitable habitat for a northerly-distributed species in a reserve located at its southern range margin. I therefore conclude that, in topographically diverse areas, where a wide range of temperature conditions can be encountered, climatic variables should be considered at spatial resolutions relevant to individuals of species whose distributions are modelled using the 'climate-envelope' approach rather than the coarse-resolution data that are currently used.
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Williams, Julian. "Carbon dioxide uptake of field-grown ash (Fraxinus-excelsior L.) trees exposed to ozone episodes." Thesis, University of Sussex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308839.
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Medeiros, Alexandre dos Santos. "Influ?ncia da pedoforma sobre a composi??o flor?stica e a estrutura da floresta estacional fluminense,Pinheiral - RJ." Universidade Federal Rural do Rio de Janeiro, 2015. https://tede.ufrrj.br/jspui/handle/jspui/1467.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
he different environmental conditions promoted by geomorphological changes, make the recovery of forest ecosystems of the Atlantic Forest challenging. In the southern state of Rio de Janeiro, where there are the semideciduous seasonal forests, degradation promoted during the coffee cycle and the current urban sprawl, restricted the seasonal forests to small fragments, responsible for ground cover, water harvesting, shelter for native fauna and representation of regional floristic diversity. Such fragments occur on geomorphological landforms variations called concave and convex, able to determine the behavior of surface water and influence the ecological dynamics of plant communities occurring. Studies to date do not allow to determine specific environmental standards between landforms, as only relate the soil variations catenary gradient and its influence on the distribution of species. Thus, it is necessary to formulate a replicable design, able to identify edaphic and microclimatic standards specific to the concave and convex landforms, and determine its influence on the distribution of species. To this end, we selected three concave landforms and three convex to perform the study, and installed 54 plots of 100m2 each landform. In each plot were collected for the phytosociological study, the diameter and height of tree species with DAP?5cm. The phytosociological parameters were calculated diversity indices, floristic similarity the sample sufficiency and compared the structural means by 5% Levene test. In each plot, soil samples were collected at depths of 0-5, 5-10 and 10-20 cm, totaling 108 samples composed of five single samples, used for grain size analysis and chemical soil fertility. The pattern of distribution of species was correlated with soil and microclimate variables of each landform simultaneously with the aid of multivariate analysis reductional (Multivariate Factor Analysis, PCA), ordenativas (Canonical Correlation Analysis and Canonical Correspondence) and agglomerative (Hierarchical Cluster). The results indicate subtle differences between soil conditions and a specific microclimate between landforms, capable of influencing the distribution of specific groups of species, however, without characterizing the formation of different plant communities. Considering the specific environmental conditions of each landform, the main variables that coordinate and species related to these conditions, it was possible to offer technical support for recupara??o of degraded and disturbed areas, as well as the enrichment of Forest ecosystems fragments of Atlantic Forest
As diferentes condi??es ambientais promovidas por varia??es geomorfol?gicas, tornam a recupera??o de ecossistemas florestais da Floresta Atl?ntica um grande desafio. Na regi?o Sul do Estado do Rio de Janeiro, onde ocorrem as Florestas Estacionais Semideciduais, a degrada??o promovida durante o ciclo do caf? e o atual crescimento urbano desordenado, restringiram as Florestas Estacionais a pequenos fragmentos, respons?veis pela cobertura do solo, capta??o de ?gua, abrigo para fauna nativa e representa??o da diversidade flor?stica regional. Tais fragmentos ocorrem sobre varia??es geomorfol?gicas denominadas pedoformas c?ncavas e convexas, capazes de determinar o comportamento das ?guas superficiais e influenciar a din?mica ecol?gica das comunidades vegetais ocorrentes. Estudos realizados at? o momento n?o permitem determinar padr?es ambientais espec?ficos entre pedoformas, pois relacionam apenas as varia??es ed?ficas ao gradiente caten?rio e sua influ?ncia sobre a distribui??o das esp?cies. Desta forma, faz-se necess?ria a formula??o de um delineamento replic?vel, capaz de identificar padr?es ed?ficos e microclim?ticos espec?ficos para as pedoformas c?ncavas e convexas, al?m de determinar sua influ?ncia sobre a distribui??o das esp?cies. Para tal, foram selecionadas tr?s pedoformas c?ncavas e tr?s convexas para realiza??o do estudo, sendo instaladas 54 parcelas de 100m2 em cada pedoforma. Em cada parcela foram coletados, para o estudo fitossociol?gico, o di?metro e altura das esp?cies arb?reas com DAP?5cm. Foram calculados os par?metros fitossociol?gicos, ?ndices de diversidade, similaridade flor?stica, a sufici?ncia amostral e comparadas as m?dias estruturais pelo teste de Levene a 5%. Em cada parcela foram coletadas amostras de solo nas profundidades de 0-5, 5-10 e 10-20 cm, totalizando 108 amostras compostas por cinco amostras simples, utilizadas para as an?lises granulom?tricas e da fertilidade qu?mica do solo. O padr?o de distribui??o das esp?cies foi correlacionado com as vari?veis ed?ficas e microclim?ticas de cada pedoforma simultaneamente, com auxilio de an?lises multivariadas reducionais (An?lise Fatorial Multivariada, PCA), ordenativas (An?lise de Correla??o Can?nica e Correspond?ncia Can?nica) e aglomerativas (Cluster Hier?rquico). Os resultados indicam diferen?as sutis entre as condi??es ed?ficas e um microclima espec?fico entre pedoformas, capaz de influenciar a distribui??o de grupos espec?ficos de esp?cies, por?m, sem caracterizar a forma??o de comunidades vegetais distintas. Considerando a condi??o ambiental espec?fica de cada pedoforma, as principais vari?veis que as coordenam e as esp?cies relacionadas a tais condi??es, foi poss?vel oferece subs?dios t?cnicos para recupara??o de ?reas degradas e perturbadas, bem como o enriquecimento de fragmentos de ecossistemas Florestais da Floresta Atl?ntica
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Lima, Nádia Gilma Beserra de. "Interação dos atributos climáticos nos manguezais do litoral sul de São Paulo e sua relação com os controles climáticos." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-08052015-125807/.
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Os manguezais estão entre os ecossistemas, biologicamente, mais produtivos e importantes do mundo, fornecendo bens e serviços exclusivos para as sociedades e os sistemas costeiros. Entre suas funções destacam-se a estabilização da linha de costa e a redução do impacto de fenômenos extremos, como em casos de tempestades e furacão. No entanto, esse ecossistema têm apresentado alterações significativas oriundas da influência antrópica no ambiente, que modificam a cobertura vegetal e que, por sua vez, influenciam todo o ecossistema, inclusive nas interações microclimáticas. A pesquisa tem como objetivo avaliar a relação existente entre os controles (estrutura da vegetação, variação da maré e sistemas atmosféricos) e atributos climáticos (temperatura do ar, umidade absoluta do ar, radiação solar global, vento e precipitação) no manguezal localizado na Barra do Ribeira-Iguape/SP. Para isso, instalou-se uma torre microclimática contendo duas estações meteorológicas de forma a obter uma análise da variação dos atributos climáticos acima e abaixo do dossel de manguezal. Além disso, analisaram-se ainda as características estruturais da vegetação do manguezal. Constatou-se um aumento na transmissividade da radiação solar no dossel do manguezal, uma redução no albedo e uma diminuição na interceptação vegetal, que está associada a degradação do bosque, que não possui indivíduos novos que prosperam no ambiente, portanto sem renovação do ecossistema, resultado da presença de macrófitas ao longo da área de estudo. Comprovou-se o importante papel da maré no manguezal, contribuindo com entrada e saída de energia, favorecendo o resfriamento/aquecimento relativo do ambiente. Concluiu-se que, do ponto de vista microclimático, há diferenças significativas entre o que acontece acima e abaixo do dossel no manguezal, com diferenças superiores a 5°C, como no caso da temperatura máxima ou ainda entre a temperatura do solo e do ar com diferenças que ultrapassaram 10°C. É perceptível, nesse nível escalar, o acoplamento entre as escalas climáticas superiores com o nível microclimático. Observou-se como os atributos climáticos se conectam e como as diferenças entre os atributos climáticos ficam evidentes em escalas temporais inferiores.Biologically, the mangrove ecosystems are among the most productive and important in the world, providing resources and services exclusive to societies and coastal systems. Its functions include the stabilization of the shoreline and reduction the impact of extreme weather events such as in cases of storms and hurricane. However, this ecosystem have been presenting significant changes arising from anthropogenic influence on the environment, modifying the vegetation and that, in turn, influence the entire ecosystem, including the microclimatic interactions. The research aims to assess the relation between controls (vegetation structure, tide variations and atmospheric systems) and climatic attributes (air temperature, absolute humidity, solar radiation, wind and rainfall) in the mangrove on the bar the Ribeira-Iguape/SP. To this end, was installed one microclimatic tower containing two weather stations to obtain an analysis of climatic attribute variations above and below the canopy of mangrove. Moreover, was analyzed the structural features of the mangrove vegetation. It was found an increase in transmissivity of solar radiation in the mangrove canopy, a reduction in albedo and a decrease in vegetable interception. These changes are associated with the degradation of the forest, who do not have new individuals who thrive in the environment, there is no renewal of the ecosystem as a result of the presence of macrophytes in the study area. It was proven the important role of tidal in mangrove areas, contributing with input and output power, favoring the cooling / heating relative on the environment. It was concluded that, from the microclimatic point of view, there are significant differences above and below the mangrove canopy. In the case of the maximum temperature, the differences were greater than 5 ° C and exceed 10 ° C between the air and soil temperature. It is noticeable in this scalar level, the coupling between the upper climatic scales with the microclimate level. Was observed how the climatic attributes are connected and how the differences between the climatic attributes are evident in inferior temporal scales.
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SILVA, NETO Sinval Peixoto Orrico da. "Aclimatização de mudas de cana-de-açúcar em ambiente protegido sob dois tipos de malha de sombreamento." Universidade Federal Rural de Pernambuco, 2012. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/5695.
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Based on the fact that the sugar-alcohol sector is a growing activity, driven by investments in production technology, the State of Pernambuco has excelled in this scenario, as the use of technique of in vitro propagation. Accordingly, this work sought to analyze the microclimate and evaluate the growth and development of sugarcane seedlings in acclimatization under two types of roofs in protected environment. The survey was conducted by the experimental area of Usina São José, in the municipality of Igarassú-PE, latitude of 7° 48' 37.32 "S, longitude 34° 59' 49.23"O and height of 34 m. The protected environment was covered with milky plastic and divided into two environments, an associated shading mesh termorreflective (TA) and the other associated with black shading mesh (TB). The variables studied were: meteorological variables (solar radiation, air temperature, relative humidity) and crop variables (stem length, diameter of the stem, leaf length, number of leaves, plant height and leaf area). 12 trays with 108 tubes each, were employed both for TA and TB, being randomly chosen for the biometric monitoring 4 tubes. The experimental design used was entirely casualized (DIC) and Tukey test (p<0.05) for comparing the averages. The production environment under TA provided the best biometric results of development of seedlings from sugarcane, as a result of the greater availability of solar radiation in the production environment.
Baseado no fato de que o setor sucroalcooleiro é uma atividade em pleno crescimento, impulsionado por investimentos em tecnologia de produção, o Estado de Pernambuco tem-se destacado nesse cenário, como a utilização de técnica de propagação in vitro. Nesse sentido, objetivou-se com este trabalho analisar o microclima e avaliar o crescimento e desenvolvimento de mudas de cana-de-açúcar em aclimatização sob dois tipos de coberturas em ambiente protegido. A pesquisa foi conduzida junto à área experimental da Usina São José, situada no município de Igarassú - PE, latitude de 7°48’37,32” S, longitude de 34°59’49,23” O e altitude de 34 m. O ambiente protegido foi coberto com plástico leitoso e dividido em dois ambientes, um associado a malha de sombreamento termorrefletora (TA) e outro associado a malha de sombreamento preta (TB). As variáveis estudadas foram: variáveis meteorológicas (radiação solar, temperatura do ar, umidade relativa do ar) e variáveis de cultura (comprimento do colmo, diâmetro do colmo, comprimento da folha, número de folhas, altura da planta e área foliar). Utilizou-se 12 bandejas com 108 tubetes cada, tanto para TA quanto para TB, sendo escolhidos aleatoriamente 4 tubetes para o acompanhamento biométrico. O delineamento experimental utilizado foi Inteiramente casualizado (DIC) e o teste de Tukey (p<0,05) para comparação entre as médias. O ambiente de produção sob TA proporcionou os melhores resultados biométricos de desenvolvimento das mudas de cana-de-açúcar, em decorrência da maior disponibilidade de radiação solar neste ambiente de produção.
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Peng, Renkang. "The influence of microclimate on the spatial distribution of flying insects." Thesis, University of Leeds, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293717.
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Johnson, Bruce Edward. "An aircraft and provide information about flight performance and local microclimate." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/5310.
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Includes abstract.Includes bibliographical references
The application of using Unmanned Aerial Vehicles (UAVs) to locate thermal updraft currentsis a relatively new topic. It was first proposed in 1998 by John Wharington, and, subsequently, several researchers have developed algorithms to search and exploit thermals. However, few people have physically implemented a system and performed field testing. The aim of this project was to develop a low cost system to be carried on a glider to detect thermals effectively. A system was developed from the ground up and consisted of custom hardware and software that was developed specifically for aircraft. Data fusion was performed to estimate the attitude of the aircraft; this was done using a direction cosine (DCM) based method. Altitude and airspeed data were fused by estimating potential and kinetic energy respectively; thus determining the aircraft’s total energy. This data was then interpreted to locate thermal activity. The system comprised an Inertial Measurement Unit (IMU), airspeed sensor, barometric altitude sensor, Global Positioning System (GPS), temperature sensor, SD card and a realtime telemetry link. These features allowed the system to determine aircraft position, height, airspeed and air temperature in realtime. A custom-designed radio controlled (RC) glider was constructed from composite materials in addition to a second 3.6 m production glider that was used during flight testing. Sensor calibration was done using a wind tunnel with custom designed apparatus that allowed a complete wing with its pitot tube to be tested in one operation. Flight testing was conducted in the field at several different locations over the course of six months. A total of 25 recorded flights were made during this period. Both thermal soaring and ridge soaring were performed to test the system under varying weather conditions. A telemetry link was developed to transfer data in realtime from the aircraft to a custom ground station. The recorded results were post-processed using Matlab and showed that the system was able to detect thermal updrafts. The sensors used in the system were shown to provide acceptable performance once some calibration had been performed. Sensor noise proved to be problematic, and time was spent alleviating its effects.
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Emery, Keith Martin. "Population dynamics of Birdsfoot trefoil in relation to disease and microclimate /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9842525.
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Valle, Benoît. "Modélisation et optimisation de la croissance de la laitue dans un système agrivoltaïque dynamique." Thesis, Montpellier, SupAgro, 2017. http://www.theses.fr/2017NSAM0017.
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L’agrivoltaïque, combinaison de panneaux photovoltaïques et d’une culture sur le même sol, a été proposé en 1982 comme solution au conflit d’usage des sols. Lancé en 2010 à Montpellier, le concept associant panneaux fixes et diverses cultures a fait la preuve d’une productivité combinée de la parcelle améliorée grâce, notamment, à l’acclimatation de la culture à l’ombre. Dans cette thèse, les panneaux fixes ont été échangés par des panneaux orientables au cours de la journée. L’objectif était d’optimiser l’orientation des panneaux pour maximiser la productivité combinée de la parcelle sans pénaliser la culture. Pour cela, la croissance et le développement de laitues ont été analysés en conditions contrôlées et en plein champ sous différentes modalités d’ombrage par panneaux fixes ou mobiles. Les panneaux mobiles ont permis d’améliorer la productivité combinée de la parcelle par rapport à des panneaux fixes, avec un maintien de la production agricole dans certaines conditions. Une approche écophysiologique basée sur le développement de la plante, sa capacité à intercepter et convertir le rayonnement en biomasse, a révélé que les modalités d’ombrage avaient peu d’impact sur la mise en place de la surface foliaire malgré des différences de biomasse accumulée en rapport avec le rayonnement transmis à la plante. Des modifications du développement foliaire ont conduit à une meilleure utilisation du rayonnement transmis lorsque celui-ci était réduit. Ce travail a débouché sur une modélisation de l’impact de l’orientation des panneaux sur la biomasse des laitues permettant d’optimiser le pilotage des panneaux en fonction du scénario climatique et des objectifs de productionsAgrivoltaic systems, combining solar panels and crops on the same land were proposed in the early 1980’s as a solution to solve land use conflict. Introduced in 2010 in Montpellier, the concept has proven itself associating fixed panels to multiple food crops. Total land productivity was improved, thanks to plant acclimation to shade. In this thesis, fixed panels were replaced with mobile panels, adjustable along the day. The aim of this work was to optimize solar panel orientations to maximise total land productivity without threatening the crop culture. Growth and development of lettuces were analysed in controlled conditions and in the field under several shading conditions by fixed or mobile panels. Total land productivity was improved with mobile panels in comparison with fixed panels, maintaining lettuce yield under certain conditions. Through an ecophysiological approach based on plant development and its ability to intercept and convert light into biomass, the different shading conditions were shown to have a small impact in the plant leaf area dynamic despite large differences in accumulated dry mass associated with transmitted radiation at the plant level. This was due to differences in leaf development resulted in higher use of the transmitted radiation when it was reduced. This study proposed a modelling approach of the incidence of panel orientations on lettuce dry mass at harvest. The model allows an optimisation of solar panels controlling as a function of climate scenario and crop and electricity production objectives
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Balls, Graham Roy. "Investigating influences on plant ozone sensitivity using artificial neural networks." Thesis, Nottingham Trent University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336972.
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Lima, Linccon de Carvalho. "Conforto térmico em espaços abertos: estudo de caso em um Parque Urbano na cidade de João Pessoa-PB." Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/9131.
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Studies of thermal comfort in climatic chambers have the limitation of disregarding the user's adaptation to the environmental conditions. In order to overcome limitations of currentelly thermal comfort models, new investigations has been conducted to identify the thermal comfort in open spaces or free running buildings. Inserted in this context, this study has as general objective to evaluate the thermal sensation of the visitors of an urban park (Bica) in João Pessoa-PB, a city of hot and humid weather climate in Northeastern Brazil. As methodology, we used microclimatic monitoring of the variables: air temperature, globe temperature, humidity, wind speed and solar radiation. Questionnaires were also applied to visitors to assess the feeling of thermal comfort within the park. The microclimatic data were collected with the aid of a portable meteorological station DAVIS and a thermal stress meter - TGD300. To carry out the statistical analyzes was used the STATISTIC 7.0 program. Through statistical analysis it was possible to identify a comfort range between 23-31°C. The logistic regression model showed that three climate variables (air temperature, wind speed and mean radiant temperature) have significant effect on the thermal sensation vote felt by respondents. When the thermal sensation vote was compared to the PMV/PPD index, it was verified in loco was always in a lower category to the PMV. The results found in this research can help in planning the city in the search for a more banlanced urban environmrt, rspecially with regard to thermal confort.
Estudos de conforto térmico em câmara climatizada apresentam a limitação de desconsiderar a adaptação do indivíduo às condições ambientais. Com objetivo de superar limitações dos modelos atuais de conforto térmico, pesquisas têm sido realizadas para identificar os limites de conforto em ambientes sem climatização e em condições naturais, dentre elas, destacam-se os estudos de conforto em espaços abertos. Inserido nesse contexto este estudo tem como objetivo geral avaliar a sensação térmica dos visitantes de um parque urbano (Bica) em João Pessoa-PB, uma cidade de clima quente e úmido no nordeste do Brasil. Como metodologia utilizou-se de monitoramento microclimático das variáveis: temperatura do ar, temperatura do globo, umidade, velocidade do vento e radiação solar. Também foram aplicados questionários aos visitantes a fim de avaliar a sensação de conforto térmico dentro do parque. Os dados microclimáticos foram coletados com auxilio de uma mine estação meteorológica portátil DAVIS e um medidor de stress térmico- TGD300. Para realizar as análises estatísticas foi utilizado o programa STATISTIC 7.0. Através da análise estatística foi possível identificar um intervalo de conforto de 23° a 31°C, o modelo de regressão logística mostrou que três variáveis climáticas (temperatura do ar, velocidade do vento, temperatura radiante média) têm influência sobre o voto de sensação térmica dos entrevistados. Quando o voto de sensação térmica foi comparado com o índice de conforto PMV/PPD observaram-se diferenças significativas entre as duas variáveis, a sensação térmica verificada in loco esteve sempre em uma categoria inferior ao PMV. Os resultados encontrados nesta pesquisa podem auxiliar ao planejamento da cidade na busca por um ambiente urbano mais equilibrado especialmente no que se refere ao conforto térmico.
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Bertozzi, Barbara. "Feasibility study for understanding ice cave microclimate through thermo-fluid dynamics approaches." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
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Ice caves are classified as sporadic permafrost phenomena and consist of lava tubes or cave systems in which perennial ice forms. Ice within caves can be very old and can carry important information on permafrost conditions, climate changes and past climates. Until now, these systems have been investigated mainly with an experimental approach. A critical topic in ice cave studies is the understanding of how the internal environment interacts with the external and how these systems react to changes in the external conditions. In this thesis, a new numerical approach to understand ice cave microclimate is proposed. Numerical studies can contribute greatly to a better understanding of the processes involved in the formation and preservation of the ice in cave. Furthermore, computational fluid dynamic methods can be a valuable support to define new experimental setups and to interpret experimental results.
The cave studied in this work is Leupa ice cave, located in Friuli Venezia Giulia region. Air flows inside Leupa ice caves were characterized with an integrated approach using both experimental and numerical methods. A general approach was initially adopted and three representative days were identified to investigate which circulation patterns can develop under different environmental conditions. The comparison of numerical and experimental data permitted to evaluate the quality of the simulations and to identify the main problematics that need to be investigated further. Deeper investigations were then performed for a single day to investigate the temperature and boundary conditions effect on the flow thermo-dynamics inside the cave.
New insights on the fluid-dynamic behavior of Leupa ice cave are achieved, showing that numerical methods could represent a powerful tool to study ice caves, improving and integrating the information that could be obtained from standard experimental measurements.
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Lam, Fung Ki. "Simulating the Effect of Microclimate on Human Behavior in Small Urban Spaces." UNIVERSITY OF CALIFORNIA, BERKELEY, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3499000.
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Sommerfeldt, Nelson. "Demonstrating the significance of microclimate on annual building energy simulations using RadTherm." Thesis, KTH, Uthålliga byggnadssystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-102850.
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Buildings account for over 35% of the energy demand in OECD countries, making them a prime target for improvement. (EIA 2011) To help building owners reduce energy usage, ratings systems such as LEED have been developed. A prerequisite for certification is the demonstration of energy efficiency through computer modeling; however, the complex nature of building energy simulations too often leads to errors of up to 30% (Turner and Frankel 2008). One source of significant error can be the assumptions made of environmental conditions, which are often simplified to speed up simulations. To demonstrate the significance of active microclimate modeling, a building energy model combined with a microclimate model has been created in RadTherm, a commercial CAE thermal solver. Simulations are run using Passive House construction in three types of environments, and demonstrate an increase in energy demand over an annual time scale when microclimatic components are included. The increase in demand is less than 1%, however the decrease in radiant heat losses are up to 30%. Using the same methodology with revisions to the building construction and urban geometry, a larger increase in energy demand is expected.
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Al-Kindy, Adil. "Macro and microclimate effects on cover zone properties of field cured concrete." Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/12446.
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Three sets of concrete blocks were cast to investigate the effects of natural exposure conditions, at the macro and microclimate scale, and field curing on the performance and durability of OPC and OPCjGGBS concretes. These are termed the Loughborough winter series, the Loughborough summer series and the Muscat summer series. Three concrete mixes were investigated in the two Loughborough series (30 and 50 MPa OPC concrete mixes and a 30 MPa OPCjGGBS concrete mix) and two in the Muscat weather series (the two 30 MPa concretes). A group of specimens were cast with each mix consisting of 600 x 500 x 150mm concrete blocks plus control cubes and prisms. The samples were cured in-situ and exposed to a range of curing methods and microclimates. Surface zone properties (up to 50mm depth) were evaluated by air permeability, sorptivity, carbonation, thermogravimetry (TG) and mercury intrusion porosimetry (MIP) tests, conducted after 3 and 12 months of site exposure. The results revealed distinct variations due to macroclimate, microclimate, curing, concrete type and age. The air permeability, sorptivity and carbonation of the concrete exposed under moderate and rainy conditions of a Loughborough summer season were lower than identical concrete cast and cured during a very cold and dry Loughborough winter season. Further, the sorptivity of concrete subjected to the hot and dry climatic conditions of Muscat was significantly higher than companion samples subjected to the temperate Loughborough climate. Significant variations in properties were observed within the two sides of the same concrete element, each subjected to a different microclimate. The air permeability, sorptivity, carbonation and porosity were reduced with increased hessian curing duration. However, premature drying of wet hessian during curing had an adverse effect on concrete quality as this produced concrete of higher permeability and carbonation than non-cured concrete. The application of controlled permeability formwork was effective in improving the concrete's sub-surface properties. The curing affected zone (CAZ) extended to approximately 20mm below the surface of the concrete that was exposed to the Loughborough winter and summer climate, and 40-50mm for the concrete exposed to the Muscat climate, with notable variation in properties due to climate and curing. The TG and MlP results provided insights into the mechanisms associated with the variations in the three concrete's properties due to natural field exposure.
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Poon, Hao-chi Cynthia, and 潘顥之. "Numerical simulation of turbulent flow and microclimate within and above vegetation canopy." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45589677.
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Malheiro, Aureliano Natalio Coelho. "Microclimate, yield and water-use of vineyards in the Douro Region, Portugal." Thesis, Cranfield University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426069.
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Bell, Sophie Cressida. "The breeding ecology of the blue tit in relation to temperature microclimate." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/42500.
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With warmer springs we observe earlier Spring phenologies. Long-term trends for earlier phenologies in warmer years have been demonstrated using population mean responses against temporal, altitudinal and latitudinal gradients. Temperature driven changes in phenology are measurable in a model system such as the oak-caterpillar-blue tit and the degree of change from one trophic level to the next can be compared across the network. The majority of studies on such a system focus on population mean trends. In this study I construct a geospatial model of temperature microclimates and test if variation in the phenologies of the simple oak, caterpillar, blue tit ecological network corresponds to variation in temperature across a single study site. Temperature traces are predicted with relative ease to a robust degree using the statistical modelling approach and given the known environmental, seasonal and synoptic weather trends for the location and time of interest. A microclimate modelling approach removes the constraint of a restricted temperature data-collection period and data is not limited to the site or position of the logger. This enables the comparison of behavioural responses amongst individuals as well as within individuals. I demonstrate that similar patterns of phenology are observed across the microclimates of a single study system as are observed for the same study system over time. More importantly by creating individual-specific temperature profiles I am able to compare the phenologies at each stage of the network to different temperature regimes as they occur under natural conditions. I find that not only do the three trophic levels differ in their periods of sensitivity to temperature change, but also that within these time-windows the phenologies of the tree, herbivore and bird are associated with differing temperature parameters. In addition to an effect on the timing of breeding, I also find an effect of microclimate temperature on incubation behaviour and female condition across the breeding effort. Climate change can lead to the uncoupling of links within ecological networks, known as trophic mismatch, as the environment of cue perception becomes disassociated from the environment of peak energy demand and selection. Given that the different trophic levels are sensitive to temperature change during different phases of Spring, I explicitly test whether temperature regimes are consistent across the Spring season and what impact differing temperatures between phases has on the breeding success of the apex predator. I find that not only are different temperature parameters not collinear, but that temperature changes are not concomitant across the Spring season. I therefore find support for the theory that trophic mismatch and blue tit nesting success is not just driven by warming temperatures, but by when temperature change occurs.