It is believed that the extremely hot European summer in 2003, where tens of thousands died in buildings, will become the norm by the 2040s, and hence there is the urgent need to accurately assess the risk that buildings pose. Thermal simulations based on warmer than typical years will be key to this. Unfortunately, the existing warmer than typical years, such as probabilistic Design Summer Years (pDSYs) are not robust measures due to their simple selection method, and can even be cooler than typical years. This study developed two new summer reference years: one (pHSY-1) is suitable for assessing the occurrence and severity of overheating while the other (pHSY-2) is appropriate for evaluating the thermal stress. Both have been proven to be more robust than the pDSYs. In addition, this study investigated the spatial variation in overheating driven by variability in building characteristics and the local environment. This variation had been ignored by previous studies, as most of them either created thermal models using building archetypes with little or no concern about the influence of local shading, or assumed little variation in climate across a landscape. For the first time, approximately a thousand more accurate thermal models were created for a UK city based on the remote measurement including building characteristics and their local shading. By producing overheating and mortality maps this study found that spatial variation in the risk of overheating was considerably higher due to the variability of vernacular forms, contexts and climates than previously thought, and that the heat-related mortality will be tripled by the 2050s if no building and human thermal adaptations are taken. Such maps would be useful to Governments when making cost-effective adaptation strategies against a warming climate.

Fire is the primary natural disturbance vital to the ecological integrity of Quetico Provincial Park, Ontario, Canada. A new provincial park planning process (i.e., Class Environmental Assessment) has required the review of Quetico’s Fire Management Plan. To support this review, large and severe (stand-replacing) Quetico fires were studied using 1966 Ontario Ministry of Natural Resources (OMNR) forest resource inventory (FRI) mapping. A Geographic Information Systems (GIS) database of the FRI was created and updated with the OMNR digital fire atlas. This database was used as a time-since-fire and fire interval dataset to estimate fire frequency. It also served to archive the 1966 FRI for the largest protected area in the transition between the Boreal and Great Lakes-St. Lawrence forest regions. Non-parametric (Kaplan-Meier) survival analysis was used to estimate survival functions and mean fire intervals (i.e., the expected time between two consecutive stand-replacing fires for any location within the Park). Previous studies that have used Kaplan-Meier survival analysis methods have based fire frequency estimates solely on time-since-fire data. However, time-since-fire data cannot be equated with fire interval data when using non-parametric methods. At least one fire interval is required to obtain reliable results. The mean fire interval for the entire 475,782 ha Park between the years 1668 and 2007 was 230 years. Performing the analysis on various geographic and temporal partitions revealed fire frequency spatial and temporal variability. A constant (independent of time-since-fire) probability of burning was not observed for Quetico which is contrary to accepted conjecture for northwestern Ontario boreal/mixed-wood forests. A current fire cycle was also estimated for the Park (342 years) using the digital fire atlas. The results suggested that use of historical static fire frequency estimates as fire management prescriptions may not be justified given considerable fire frequency temporal variability. The observed fire frequency spatial variability suggests that studies should be undertaken at coarser scales than is the norm to characterise the regions fire regime in support of landscape level fire management planning.

Fire is the primary natural disturbance vital to the ecological integrity of Quetico Provincial Park, Ontario, Canada. A new provincial park planning process (i.e., Class Environmental Assessment) has required the review of Quetico’s Fire Management Plan. To support this review, large and severe (stand-replacing) Quetico fires were studied using 1966 Ontario Ministry of Natural Resources (OMNR) forest resource inventory (FRI) mapping. A Geographic Information Systems (GIS) database of the FRI was created and updated with the OMNR digital fire atlas. This database was used as a time-since-fire and fire interval dataset to estimate fire frequency. It also served to archive the 1966 FRI for the largest protected area in the transition between the Boreal and Great Lakes-St. Lawrence forest regions. Non-parametric (Kaplan-Meier) survival analysis was used to estimate survival functions and mean fire intervals (i.e., the expected time between two consecutive stand-replacing fires for any location within the Park). Previous studies that have used Kaplan-Meier survival analysis methods have based fire frequency estimates solely on time-since-fire data. However, time-since-fire data cannot be equated with fire interval data when using non-parametric methods. At least one fire interval is required to obtain reliable results. The mean fire interval for the entire 475,782 ha Park between the years 1668 and 2007 was 230 years. Performing the analysis on various geographic and temporal partitions revealed fire frequency spatial and temporal variability. A constant (independent of time-since-fire) probability of burning was not observed for Quetico which is contrary to accepted conjecture for northwestern Ontario boreal/mixed-wood forests. A current fire cycle was also estimated for the Park (342 years) using the digital fire atlas. The results suggested that use of historical static fire frequency estimates as fire management prescriptions may not be justified given considerable fire frequency temporal variability. The observed fire frequency spatial variability suggests that studies should be undertaken at coarser scales than is the norm to characterise the regions fire regime in support of landscape level fire management planning.

The properties of natural soil are inherently variable and influence design decisions in geotechnical engineering. Apart from the inherent variability of the soil, the variability may arise due to measurement of soil properties in the field or laboratory tests and model errors. These wide ranges of variability in soil are expressed in terms of mean, variance and autocorrelation function using probability/reliability based models. The most common term used in reliability based design is the reliability index, which is a probabilistic measure of assurance of performance of structure. The main objective of the reliability based design is to quantify probability of failure/reliability of a geotechnical system considering variability in the design parameters and associated safety. In foundation design, reliability based design is useful compared to deterministic factor of safety approach. Several design codes of practice recommend the use of limit state design concept based on probabilistic models, and suggest that, development of reliability based design methodologies for practical use are of immense value. The objective of the present study is to propose reliability based design methodologies for pile foundations under static and seismic loads. The work presented in this dissertation is subdivided into two parts, namely design of pile foundations under static vertical and lateral loading; and design of piles under seismic loading, embedded in non-liquefiable and liquefiable soil. The significance of consideration of variability in soil parameters in the design of pile foundation is highlighted. A brief review of literature is presented in Chapter 2 on current pile design methods under vertical, lateral and seismic loads. It also identifies the scope of the work. Chapter 3 discusses the methods of analysis which are subsequently used for the present study. Chapter 4 presents the reliability based design methodology for vertically and laterally loaded piles based on cone penetration test data for cohesive soil. CPT data from Konaseema area in India is used for analysis. Ultimate limit sate and serviceability limit state are considered for reliability based design using CPT data and load displacement curves. Chapter 5 presents the load resistance factor design (LRFD) of vertically and laterally loaded piles based on load test data. Reliability based code calibrated partial factors are determined considering bias in failure criteria, model bias and variability in load and resistance. Chapter 6 illustrates a comprehensive study on the effect of soil spatial variability on response of vertically and laterally loaded pile foundations in undrained clay. Two-dimensional finite difference program, FLAC2D (Itasca 2005) is used to model the soil and pile. The response of pile foundations due to the effect of variance and spatial correlation of undrained shear strength is studied using Monte Carlo simulation. The influence of spatial variability on the propagation and formation of failure near the pile foundation is also examined. Chapter 7 describes reliability based design methodology of piles in non-liquefiable soil. The seismic load on pile foundation is determined from code specified elastic design response spectrum using pseudo-static approach. Variability in seismic load and soil undrained shear strength are incorporated. The effects of soil relative densities, pile diameters, earthquake predominant frequencies and peak acceleration values on the two plausible failure mechanisms; bending and buckling are examined in Chapter 8. The two-dimensional finite difference analysis is used for dynamic analysis. A probabilistic approach is proposed to identify governing failure modes of piles in liquefiable soil in Chapter 9. The variability in the soil parameters namely SPT-N value, friction angle, shear modulus, bulk modulus, permeability and shear strain at 50% of modulus ratio is considered. Monte Carlo simulation is used to determine the probability of failure. A well documented case of the failed pile of Showa Bridge in 1964 Niigata earthquake is considered as case example. Based on the studies reported in this dissertation, it can be concluded that the reliability based design of pile foundations considering variability and spatial correlation of soil enables a rational choice of design loads. The variability in the seismic design load and soil shear strength can quantify the risk involved for pile design in a rational basis. The identification of depth of liquefiable soil layer is found to be most important to identify failure mechanisms of piles in liquefiable soil. Considerations of soil type, earthquake intensity, predominant frequency of earthquake, pile material, variability of soil are also significant.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-11-10T13:49:36Z No. of bitstreams: 1 CÍCERO AURÉLIO GRANGEIRO LIMA - DISSERTAÇÃO PPGECA 1992..pdf: 25126677 bytes, checksum: 344ec8cc3722c36124b4e9b1b88b50b3 (MD5) / Made available in DSpace on 2018-11-10T13:49:36Z (GMT). No. of bitstreams: 1 CÍCERO AURÉLIO GRANGEIRO LIMA - DISSERTAÇÃO PPGECA 1992..pdf: 25126677 bytes, checksum: 344ec8cc3722c36124b4e9b1b88b50b3 (MD5) Previous issue date: 1992-11-12 / Testes de infiltração com infiltrômetro duplo anel de nível constante foram efetuados em 32 pontos de uma malha retangular de uma parcela agrícola da Fazenda Experimental da EMEPA - Pb. Ajustamentos as Leis de Philip e de Green e Ampt foram efetuados. Medições da granulometria, densidade aparente seca do solo e umidade volumétrica antes e depois dos testes foram também efetuadas. Utilizou-se a seguir técnicas de análises estatística clássica e geoestatística para caracterizar a variabilidade espacial dos parâmetros de infiltração obtidos pelos ajustamentos. Nenhum dos parâmetros estudados apresentou estrutura espacial definida. Correlações simples e múltiplas evidenciaram dependência da percentagem de Argila + Silte com o espaço físico, e independência entro os parâmetros de infiltração. Ilustrações sobre o efeito da variabilidade espacial sobro o ponto de vista agronômico o hidrológico são mostradas. / Infiltration tests with double-ring infiltrometers were performed in a 33 paint reiangular regular]y spaced grid of an agri cultural site. Fitting of the infiltration curve obtained by Philip and Green and Ampt laws allowed to obtain the sorptivity, the infiltration rate at steady state and the suction parameters of Green and Ampt,for each point. Measurements of pre- and post-humidi ty, granulometry and dry density were also performed. Classical statistical and geo-statistical techniques were used to characterize spatial variability. None of the parameters studied showed a defined spatial structure. Single and muitiple correlations showed a dependence between Cclay + siltD percentage with space but no correlation between parameters was obtained. I11ustrative considerations about spatial variability were ma de with agronomic and hydrologic applications.

Made available in DSpace on 2014-08-20T13:25:42Z (GMT). No. of bitstreams: 1 Dissertacao_Glaucia_Oliveira_Islabao.pdf: 11691653 bytes, checksum: aa0c46c1206ac7ab555f7587ceb58264 (MD5) Previous issue date: 2009-03-30 / Strawberry crop is an important option for small properties, being of great relevance for people fixation at countryside and generation and maintenance of rural jobs. Studies related to soil attributes monitoring, which can be used as soil quality indicators, are important to evaluate the sustainability of agricultural practices and to point to sound environment management, aiming to its conservation. This work intended to analyze the spatial and temporal variability of the chemical and microbiological soil attributes during the strawberry crop cycle in fourteen rural properties affiliated to the Association of Strawberry Producers of Turuçu-RS, to identify and evaluate the potential impacts of irrigation water on these attributes and to propose actions to minimize these impacts if needed. In this way, deformed soil samples were collected in four different periods at depth 0-0.20 m, to determine their chemical attributes (organic matter, active and potential acidity, CEC and at pH 7.0, base saturation and aluminum saturation), microbiological (carbon and nitrogen of microbial biomass, basal respiration and metabolic quotient) and about fertility (total nitrogen, phosphorus, potassium, copper and zinc). In order to evaluate the mean values of all attributes along the time in each property was applied the LSD mean comparison test with significance to 5%. The spatial and temporal variability of all attributes were evaluataded by means of box plots. Results indicated that between the soil chemical indicators, the mean values of potential acidity presented the major significant variation along the time, while the mean values of aluminum saturation presented the minor variation. Between the soil microbiological indicators, the mean basal respiration presented the major significant variation along the time, while the mean values of nitrogen of microbial biomass presented the minor variation. Between soil fertility indicators the mean values of copper presented the major significant variation along the time, while the mean values of zinc presented the minor variation. With regard to the spatial and temporal variability of the chemical indicators it was found that organic matter presented the greatest amplitude and the aluminum saturation the lowest. Regarding to the spatial and temporal variability of the microbiological indicators it was found that carbon of microbial biomass presented the greatest amplitude while the metabolic quotient presented the lowest. Regarding to the spatial and temporal variability of the soil fertility indicators it was found that copper presented the greatest amplitude while zinc presented the lowest. The concentrations of phosphorus, potassium, copper and zinc presented high levels in all strawberry crops. The organic matter levels were classified as low in most strawberry crops. It was not possible to identify the impact of irrigation water over the chemical and soil fertility indicators, meanwhile, there was a possible impact over the microbiological indicators, specially over the carbon and nitrogen of microbial biomass and metabolic quotient. / A cultura do morango é uma importante alternativa para pequenas propriedades, sendo de grande importância para a fixação do homem no campo e para a geração e manutenção de emprego na área rural. Estudos relativos ao monitoramento dos atributos do solo, que podem ser utilizados como indicadores de qualidade do solo, são importantes para avaliar a sustentabilidade das práticas agrícolas, além de sinalizar o manejo adequado do ambiente visando à sua conservação. Em virtude disto, este trabalho teve como objetivos estudar a variabilidade espacial e temporal dos atributos químicos e microbiológicos do solo ao longo do ciclo de produção da cultura do morango em quatorze propriedades pertencentes a Associação de Produtores de Morango do município de Turuçu/RS, identificar e avaliar os possíveis impactos da água de irrigação sobre estes atributos e propor ações para minimizar estes impactos caso existirem. Para tal, foram coletadas, em quatro diferentes épocas e na profundidade de 0-0,20 m, amostras deformadas de solo em cada uma das propriedades, determinando seus atributos químicos (matéria orgânica, acidez ativa e potencial, CTC efetiva e pH 7,0, saturação por alumínio e saturação por bases), microbiológicos (carbono microbiano, nitrogênio microbiano, respiração basal e quociente metabólico) e de fertilidade (nitrogênio total, fósforo, potássio, cobre e zinco). Para verificar o comportamento dos valores médios de todos os atributos ao longo do tempo e em cada propriedade foi aplicado o teste de comparação de médias DMS, a nível de 5% de significância, enquanto que para avaliar a distribuição temporal e espacial de todos os atributos foram construídos gráficos em caixa. Os resultados indicaram que dentre os indicadores químicos do solo, os valores médios de acidez potencial foram os que mais diferiram significativamente ao longo do tempo, enquanto que os valores médios de saturação por alumínio foram os que menos diferiram; dentre os indicadores microbiológicos do solo, os valores médios de respiração basal foram os que mais diferiram significativamente ao longo do tempo, enquanto que os valores médios de nitrogênio microbiano foram os que menos diferiram ao longo do tempo; dentre os indicadores de fertilidade do solo, os valores médios de cobre foram os que mais diferiram significativamente ao longo do tempo, enquanto que os valores médios de zinco foram os que menos diferiram; quanto a variabilidade espacial e temporal dos indicadores químicos, foi constatado que a matéria orgânica apresentou a maior amplitude e a saturação por alumínio a menor; quanto a variabilidade espacial e temporal dos indicadores microbiológicos, foi constatado que o indicador carbono microbiano apresentou a maior amplitude e o quociente metabólico a menor; quanto a variabilidade espacial e temporal dos indicadores de fertilidade, foi constatado que o cobre apresentou a maior amplitude e o zinco a menor; as concentrações dos elementos fósforo, potássio, cobre e zinco encontram-se com elevados teores em todas as lavouras de morango; os teores de matéria orgânica foram classificados como baixos na maioria das lavouras de morango envolvidas neste estudo; não foi possível identificar o impacto da adição da água de irrigação sobre os indicadores químicos e de fertilidade do solo, entretanto, houve um possível impacto sobre os indicadores microbiológicos, principalmente, verificado sobre o carbono microbiano, nitrogênio microbiano e o quociente metabólico.

A compreensão da dependência espacial das propriedades do solo vem sendo cada vez mais requerida por pesquisadores que objetivam melhorar a interpretação dos resultados de experimentos de campo fornecendo, assim, subsídios para novas pesquisas a custos reduzidos. Em geral, variáveis como, por exemplo, o teor de cálcio no solo, estudado neste trabalho, apresentam grande variabilidade impossibilitando, na maioria das vezes, a detecção de reais diferenças estatísticas entre os efeitos de tratamentos. A consideração de amostras georreferenciadas é uma abordagem importante na análise de dados desta natureza, uma vez que amostras mais próximas são mais similares do que as mais distantes e, assim, cada realização desta variável contém informação de sua vizinhança. Neste trabalho, métodos geoestatísticos que baseiam-se na modelagem da dependência espacial, nas pressuposições Gaussianas e nos estimadores de máxima verossimilhança são utilizados para analisar e interpretar a variabilidade do teor de cálcio no solo, resultado de um experimento realizado na Fazenda Angra localizada no Estado do Rio de Janeiro. A área experimental foi dividida em três regiões em função dos diferentes períodos de adubação realizadas. Neste estudo foram utilizados dados do teor de cálcio obtidos das camadas 0-20cm e 20-40cm do solo, de acordo com as coordenadas norte e leste. Modelos lineares mistos, apropriados para estudar dados com esta característica, e que permitem a utilização de diferentes estruturas de covariâncias e a incorporação da região e tendência linear das coordenadas foram usados. As estruturas de covariâncias utilizadas foram: a exponencial e a Matérn. Para estimar e avaliar a variabilidade dos parâmetros utilizaram-se os métodos de máxima verossimilhança, máxima verossimilhança restrita e o perfil de verossimilhança. A identificação da dependência e a predição foram realizadas por meio de variogramas e mapas de krigagem. Além disso, a seleção do modelo adequado foi feita pelo critério de informação de Akaike e o teste da razão de verossimilhanças. Observou-se, quando utilizado o método de máxima verossimilhança, o melhor modelo foi aquele com a covariável região e, com o método de máxima verossimilhança restrita, o modelo com a covariável região e tendência linear nas coordenadas (modelo 2). Com o teor de cálcio, na camada 0-20cm e considerando-se a estrutura de covariância exponencial foram obtidas as menores variâncias nugget e a maior variância espacial (sill – nugget). Com o método de máxima verossimilhança e com o modelo 2 foram observadas variâncias de predição mais precisas. Por meio do perfil de verossimilhança pode-se observar menor variabilidade dos parâmetros dos variogramas ajustados com o modelo 2. Utilizando-se vários modelos e estruturas de covariâncias, deve-se ser criterioso, pois a precisão das estimativas, depende do tamanho da amostra e da especificação do modelo para a média. Os resultados obtidos foram analisados, com a subrotina geoR desenvolvida por Ribeiro Junior & Diggle (2000), e por meio dela pode-se obter estimativas confiáveis para os parâmetros dos diferentes modelos estimados. / The understanding of the spatial dependence of the properties of the soil becomes more and more required by researchers that attempt to improve the interpretation of the results of field experiments supplying subsidies for new researches at reduced costs. In general, variables as, for example, the calcium content in the soil, studied in this work, present great variability disabling, most of the time, the detection of real statistical differences among the treatment effects. The consideration of georeferenced samples is an important approach in the analysis of data of this nature, because closer samples are more similar than the most distant ones and, thus, each realization of this variable contains information of its neighborhood. In this work, geostatistics methods that are based on the modeling of the spatial dependence, under the Gaussian assumptions and the maximum likelihood estimators, are used to analyze and to interpret the variability of calcium content in the soil, obtained from an experiment carried on at Fazenda Angra, located in Rio de Janeiro, Brazil. The experimental area was divided in three areas depending on the different periods of fertilization. In this study, data of the calcium soil content from the layers 0-20cm and 20-40cm, were used, according to the north and east coordinates. Mixed linear models, ideal to study data with this characteristic, and that allow the use of different covariance structures, and the incorporation of the region and linear tendency of the coordinates, were used. The covariance structures were: the exponential and the Matérn. Maximum likelihood, maximum restricted likelihood and the profile of likelihood methods were used to estimate and to evaluate the variability of the parameters. The identification of the dependence and the prediction were realized using variograms and krigging maps. Besides, the selection of the appropriate model was made through the Akaike information criterion and the likelihood ratio test. It was observed that when maximum likelihood method was used the most appropriate model was that with the region covariate and, with the maximum restricted likelihood method, the best model was the one with the region covariate and linear tendency in the coordinates (model 2). With the calcium content, in the layer 0-20cm and considering the exponential covariance structure, the smallest nugget variances and the largest spatial variance (sill - nugget) were obtained. With the maximum likelihood method and with the model 2 more precise prediction variances were observed. Through the profile of likelihood method, smaller variability of the adjusted variogram parameters can be observed with the model 2. With several models and covariance structures being used, one should be very critical, because the precision of the estimates depends on the size of the sample and on the specification of the model for the average. The obtained results were analyzed, with the subroutine geoR developed by Ribeiro Junior & Diggle (2000), and through this subroutine, reliable estimates for the parameters of the different estimated models can be obtained.

O presente trabalho foi realizado em cafeeiros (Coffea arabica L.) cv. Icatu Vermelho IAC 4045, cultivados a pleno sol e consorciados com banana ‘Prata An㒠(Musa AAB), em Mococa – SP (Latitude 21º 28’ S, Longitude 47º 01’ W, altitude 665m). Foi realizada a caracterização microclimática, entre outubro de 2001 e setembro de 2002, onde foram medidos a radiação solar global, saldo de radiação, velocidade do vento e temperatura e umidade relativa do ar nos dois sistemas de cultivo. No período do inverno de 2002 e 2003, foi realizado um estudo da influência das bananeiras na variabilidade espacial da temperatura do ar e folha, além do saldo de radiação, em episódios de resfriamento noturno. Realizou-se também uma caracterização aerodinâmica e energética dos cultivos, entre dezembro de 2002 e novembro de 2003, onde foram obtidos os perfis dos bulbos seco e úmido, além da velocidade do vento em sete níveis de medida. Entre julho de 2001 a junho de 2004 foram atribuídas notas de desenvolvimento fenológico dos cultivos, além de se avaliar, o crescimento das plantas em altura e diâmetro da copa. Nas safras de 2002, 2003 e 2004 foram avaliados os parâmetros de produção nos dois sistemas de cultivo, além da variabilidade desses nas parcelas do cultivo consorciado. Houve uma atenuação dos valores de radiação solar global (21%) no cultivo de café consorciado e uma redução de 16% e 48% nos valores do saldo de radiação e velocidade do vento, em relação ao cultivo a pleno sol. Com relação à temperatura e umidade do ar, foram encontradas diferenças apenas na temperatura máxima no ponto central da parcela do cultivo consorciado, que apresentou médias superiores em relação ao cultivo a pleno sol no verão e outono, e em relação ao ponto situado próximo as bananeiras na primavera, verão e outono. Nos episódios de resfriamento do ar no período noturno, apesar do cultivo consorciado apresentar menor perda radiativa, ocorreu apenas um acréscimo de 0,3ºC na temperatura do ar nos episódios amostrados, sendo que para a temperatura das folhas esses valores atingiram até 0,5ºC. Foi verificado ainda que a ação de quebra-vento das bananeiras no cultivo consorciado, promoveu alterações nos perfis de temperatura e umidade do ar, apresentando gradientes reduzidos, em relação ao cultivo a pleno sol, acima do dossel dos cafeeiros. Os valores médios dos componentes do balanço de energia nos sistemas de cultivos de café a pleno sol e consorciado não apresentaram diferenças. Nos sistemas de cultivo avaliados, o crescimento vegetativo em altura e diâmetro apresentou maior atividade vegetativa no período primavera-verão em relação ao período outono-inverno, não tendo sido encontradas diferenças significativas das taxas de crescimento, de desenvolvimento fenológico e dos índices de produção entre os cultivos. No cultivo consorciado, o ponto amostral próximo às bananeiras apresentou diferenças em relação aos demais pontos amostrados no crescimento vegetativo e desenvolvimento fenológico para algumas épocas do ano, além de apresentar menor produção por planta e maior massa de 100 sementes. / A study was carried out in coffee crop (Coffea arabica L.) cv. Icatu Vermelho IAC 4045, unshade and shaded by banana ‘Prata An㒠(Musa AAB), in Mococa, São Paulo State, Brazil (Latitude South 21º 28 ', Longitude West 47º 01 ', altitude 665m). The microclimatic measurements (solar radiation, net radiation, wind speed, air temperature and air moisture) were taken from October, 2001 to September, 2002 under different crops conditions. During the winter of 2002 and 2003, a study of the influence of the banana plants was done on space variability of air and leaf temperature, besides net radiation, for cold nights. The aerodynamic and energy characterization were done from December, 2002 to November,2003, by obtining the profiles of the bulb wet and dry air temperature, also measurements the wind speed in seven different levels. From July, 2001 to June, 2004 phenological data for the coffee crops were taken. The growth of the plants concerning height and diameter was also evaluated. The harvests of 2002, 2003 and 2004 were appraised by the production parameters, and their variability for different positions in shaded coffee crop. The banana trees reduced the incoming solar radiation to the coffee crop by 21%, and by 16% and 48% in the values of the net radiation and wind speed, respectively. Concerning on air temperature and air mosture, differences were found just for the maximum air temperature at the central point of the shaded crop, showing higher averages in relation to the unshaded crop during the summer and autumn, and also in relation to the nearest point to the banana plants during the spring, summer and autumn. During cold nights, spite the shaded coffee crop showing smaller radiation loss, an increment of 0.3ºC in the air temperature was observed and for the leaves the values reached 0.5ºC. It was verified an windbreak action of fanlight of the banana trees in the shaded crop, promoting deviation in air temperature and humidity profiles, showing reduced gradients, in relation to the unshaded crop, above the coffee plants canopy. The mean values of the energy balance components for the different systems of cultivation did not show difference. In the cultivation systems evaluated, the vegetative growth in height and diameter showed higher vegetative activity during the spring-summer period in relation to the autumn-winter period. No significant differences of the growth taxes, of phenological development and of the yield indexes were found. In coffee crop shaded, the nearest point to the banana plants showed differences in relation to the other amostral points in vegetative growth and phenological development for some seasons of the year, besides showing smaller plant yield and higher weight of 100 seeds.

A primeira parte deste trabalho consistiu na instalação de pluviógrafos e linígrafos e levantamento de eventos hidrológicos com a obtenção de dados da distribuição espacial de precipitações observadas e hidrogramas resultantes. Experimentos de infiltração de água no solo foram realizados a partir de infiltrômetro de disco a fim de caracterizar a variabilidade espacial da condutividade hidráulica na bacia, obtendo-se dois conjuntos de dados que mostraram ser lognormalmente distribuídos com médias iguais a 15,8 mm/h e 5,47 mm/h. Estudo teórico foi conduzido na segunda parte do trabalho compreendendo o desenvolvimento de modelo hidrológico. A concepção do modelo parte da premissa de que toda a área da bacia possa ser representada por células derivadas de um modelo numérico de terreno (MNT), especificando-se em cada célula o equacionamento hidráulico-hidrológico. As heterogeneidades do solo e da precipitação foram estudadas através de simulação do modelo considerando-se distribuições espaciais diferentes para a condutividade hidráulica saturada e eventos de chuva. Os resultados mostraram que as diferenças entre as vazões de pico podem ser maiores que 100% , considerando-se graus de resolução máximo e mínimo quanto à precipitação, e reafirmaram o consenso de que o conhecimento da distribuição espacial da chuva é fundamental na calibração de modelos hidrológicos distribuídos. / In first part of this work consists on the installation of pluviographic, water-height graphs and surveying of hydrological events with obtained data from spatial distribution of precipitation observed and resultant hydrograms. Experiments of water infiltration in the soil were done by an infiltrometer disc to characterize the spatial variability of hydraulic conductivity and the losses of infiltration in the basin obtaining two sets of data that showed to be lognormally distributed in average equal to 15.8 mm/h and 5.47 mm/h. A theoric study was conduced in the second part of work comprehending the development of hydrologic model distributed. The conception of the model proceed from the premise that allbasin area can be represented by cells derived from a Digital Terrain Model (DTM) specifying in each cell the hydraulic equation - hydrologic. The soil heterogeneity and the precipitation were studied by model simulation considering spatial distributions different to the hydraulic conductivity satured of the soil and to pluvial events. The results pointed out the differences among peak outflow can be more than 100% considering minimum and maximumresolution degrees as the precipitation and affirmed the consensus that the acquaintance of the pluvial spatial distribution is fundamental in the adjustment of hydrologic models distributed.

Made available in DSpace on 2014-08-20T14:36:56Z (GMT). No. of bitstreams: 1 Tese_ Alvaro_ Luiz_ Carvalho_ Nebel.pdf: 1615608 bytes, checksum: cf5d12660d9ae82ddc2e973b92c9812e (MD5) Previous issue date: 2009-04-24 / The understanding of the dynamics of the water in the soil-plant-atmosphere system, including the water availability to the crops, soil water infiltration, drainage and soil solute movement, depends on the knowledge of the relation between the soil water content and the matric potential, represented by the soil water retention curve (SWRC). However, the establishment of SWRCs is laborious and time consuming, besides being costly. A alternative is its estimate through statistical equations called Pedotransfer Functions (PTFs). The aim of this study was to evaluate the ability of some existing PTFs, in predicting the soil water retention and to capture its spatial variability structure, using geostatistical tools, when applied in a lowland soil of the south region of Brazil. For this, an experimental 10 x 10 m grid was established and soil disturbed and undisturbed samples were collected in the 0-0.20 m soil depth, totaling 100 experimental points. The following soil attributes were determined in each point: soil texture, soil organic carbon, pH, cation exchange capacity, soil bulk density, and the soil water retention curve. Eight developed PTFs for estimating gravimetric soil water content, eight for estimating volumetric water content and five for estimating the van Genuchten model parameters were evaluated using the statistical measures mean error (ME), and the root mean square error (RMSE). Results indicated that the Oliveira et al. (2002) PTF presented the best performance for estimating the gravimetric soil water content at the tension of 33kPa, with mean error (ME) value of 0.0136g.g-1, while for the gravimetric water content at tension of 1500kPa the Pidgeon (1972) FPT was the best, with ME value of -0,0054g.g-1. Concerning to the potential of describing the spatial variability structure the Bell & van Keulen (1995 and 1996) and of Urach (2007) PTFs presented the best performance based on the results from the cross validation technique. For estimating the soil water volumetric content at the tension of 10kPa the Tomasela et al. (2002) was the best (ME of 0.019cm3.cm-3), while Rawls et al. (1982) and van den Berg et al. (1997) PTFs were the best for estimating soil water content at the tension of 33kPa (ME of 0.001cm3.cm-3) and 1500kPa (ME of -0.008cm3.cm-3), respectively. The range and sill geostatistical parameters for the tension of 33kPa were reasonable estimated, while for the tension of 1500kPa they were underestimated by the evaluated PTFs. The Parametric Pedotransfer Function constructed by Vereecken et al.(1989) presented the lowest value of ME (0.0247cm3.cm-3), while the Hodnett and Tomasella (2002) PTF presented the lowest value of RMSE (0.0367 cm3.cm-3). Both PTFs well described the experimental semivariograms of the soil water content at the tensions of 10kPa and 33kPa, however their performance was not good for the tension of 1500kPa. / Estudos que envolvem a dinâmica da água no sistema solo-planta-atmosfera tais como disponibilidade de água no solo para as culturas, infiltração, drenagem e movimento de solutos no solo necessitam do conhecimento da relação entre o conteúdo de água no solo e o potencial matricial, representada pela curva de retenção de água no solo. No entanto, sua execução é laboriosa, demanda considerável tempo e custos. Uma alternativa é sua estimativa através de equações estatísticas denominadas Funções de Pedotransferência (FPTs). O objetivo deste estudo foi avaliar o desempenho de funções de pedotransferência em estimar a retenção de água no solo e capturar a sua estrutura de variabilidade espacial, usando ferramentas geoestatísticas, quando aplicadas em um solo de várzea da região sul do Brasil. Para isto, uma malha experimental de 10m x 10m foi estabelecido e amostras deformadas e indeformadas do solo foram coletadas representativas da camada de 0 0,20m, totalizando 100 pontos amostrais. Os seguintes atributos do solo foram determinados em cada ponto: textura, carbono orgânico, pH, capacidade de troca de cátions, densidade do solo e a curva de retenção de água no solo. Oito FPTs desenvolvidas para estimar o conteúdo gravimétrico de água no solo, oito para estimar o conteúdo volumétrico e cinco para estimar os parâmetros do modelo de van Genuchten foram avaliadas, usando as medidas estatísticas erro médio (ME) e raiz quadrada do erro médio ao quadrado (RMSE). Os resultados obtidos para a estimativa do conteúdo de água gravimétrico mostram que a FPT de Oliveira et al. (2002) apresentou o melhor desempenho para a tensão de 33kPa, com erro médio (ME) de 0,0136g.g-1, enquanto para a tensão de 1500kPa a FPT de Pidgeon (1972) foi melhor, com ME de -0,0054g.g-1. Com relação ao potencial de descrever a estrutura de variabilidade espacial do conjunto de dados medidos, as FPTs desenvolvidas por Bell & van Keulen (1995 e 1996) e Urach (2007) foram as que apresentaram melhor desempenho baseado nos resultados da validação cruzada. Para o conteúdo volumétrico de água retida no solo, os melhores desempenhos foram obtidos pela FPT de Tomasela et al.(2003) para a tensão de 10kPa, Rawls et al. (1982) para 33kPa e van den Berg et al.(1997) para 1500kPa, com ME iguais a 0,019cm3.cm-3, 0,001cm3.cm-3 e -0,008cm3.cm-3, respectivamente. Os parâmetros da estrutura de dependência espacial, alcance e patamar, para a tensão de 33kPa foram razoavelmente estimados, enquanto para a tensão de 1500kPa foram subestimados pelas FPTs avaliadas. A FPT paramétrica desenvolvida por Vereecken et al. (1989) apresentou o menor valor de ME (0,0247cm3.cm-3), enquanto a FPT de Hodnett e Tomasella (2002) apresentou o menor valor de RMSE (0,0367 cm3.cm-3). Ambas FPTs descreveram bem os semivariogramas experimentais do conteúdo de água retido no solo a 10kPa e 33kPa, entretanto para a tensão de 1500kPa nenhuma das FPTs testadas apresentou bom desempenho.