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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Estrutura espacial das comunidades de Ephemeroptera HAECKEL, 1896 (Insecta) em riachos da Serra da Mantiqueira e da Serra do Mar, Estado de São Paulo / Spatial structure in assemblages of Ephemeroptera Haeckel, 1896 (insecta) in streams of Serra da Mantiqueira and Serra do mar, State of São Paulo

Ana Emilia Siegloch 26 March 2010 (has links)
Este estudo teve como objetivos, i) investigar a composição taxonômica das duas vertentes da Serra da Mantiqueira (Parque Estadual de Campos do Jordão e Região de Pindamonhangaba) e da Serra do Mar (Núcleos Santa Virgínia e Picinguaba), com base na coleta de larvas e alados, ii) analisar quais as escalas espaciais (mesohábitat, riacho, vertente e serra) que melhor estruturam as comunidades de Ephemeroptera e iii) identificar e quantificar as variáveis ambientais que influenciam as comunidades de larvas de Ephemeroptera. Considerando o esforço conjunto de todos os métodos de coleta foram registradas oito famílias 33 gêneros e 21 espécies, das quais oito famílias 28 gêneros e 18 espécies na Serra da Mantiqueira e sete famílias 30 gêneros e 15 espécies no Parque Estadual da Serra do Mar. As duas serras apresentaram uma porção bastante significativa da riqueza taxonômica do Brasil, 41% e 45% dos gêneros e 80% e 70% das famílias, respectivamente. A alta riqueza registrada no estudo pode ser relacionada à metodologia de coleta empregada que abrangeu a coleta de larvas e alados e explorou diversos mesohábitats e riachos. Considerando todo o modelo hierárquico, houve variação significativa da riqueza e abundância das comunidades entre as quatro vertentes e os mesohábitats pedra e folha/corredeira. No entanto, a maior variação ocorreu entre as réplicas de um mesmo mesohábitat, refletindo o padrão de distribuição agregada das comunidades de Ephemeroptera. A maior riqueza foi encontrada no mesohábitat pedra/corredeira e na vertente que abrange o Núcleo Santa Virgínia. A ordenação mostrou tendência de segregação das amostras de cada vertente e tipo de mesohábitat. Essa tendência de segregação foi corroborada pela análise de variância multivariada (Permanova). Assim, a estrutura espacial das comunidades de larvas de Ephemeroptera parece predita pelos fatores ambientais da escala local ligadas aos mesohábitats e pelos fatores de maior magnitude da escala regional, associados às vertentes. A Análise de Redundância (RDA) evidenciou a altitude, condutividade elétrica, temperatura da água e Resumo Geral 10 largura como as variáveis ambientais locais que mais contribuíram para explicar a estrutura das comunidades. No entanto, as variáveis ambientais locais explicaram apenas 19,3% da variabilidade na abundância dos gêneros, 7,9% da variabilidade foi explicada pelas variáveis ambientais indissociáveis da matriz geográfica, 23,4% foi explicada pela posição geográfica dos riachos e 49,4% permaneceu inexplicada. Os resultados encontrados nesse estudo destacam a contribuição semelhante das variáveis ambientais locais e da posição geográfica dos riachos na estruturação das comunidades, indicando que além das variáveis ambientais locais os processos biológicos contagiosos, como dispersão, também influenciaram a estrutura das comunidades de larvas de Ephemeroptera na região estudada / The purpose of this study was to i) inventory the taxonomic composition the mayfly fauna, larva and adult, in two slopes of the Mantiqueira Mountains (Campos do Jordao State Park and Pindamonhangaba Region) and of the Serra do Mar (Santa Virginia and Picinguaba Nuclei), located in São Paulo State, ii) analyze the spatial scales (mesohabitat, stream, slope and mountain) that best explain the spatial structure of Ephemeroptera assemblages and iii) identify and quantify the environmental variables that affects the communities of Ephemeroptera larvae. In all, 8 families, 33 genera and 21 species of Ephemeroptera were recorded. In the Serra da Mantiqueira 8 families, 28 genera and 18 species were found and in the Serra do Mar, 7 families, 30 genera and 15 species. Both mountains had a very significant portion of the genera reported to Brazil (41% and 45% of genera and 80% and 70% of families, respectively). The high Ephemeroptera richness in the areas may be related to the sampling methodology used, that included the collection of larvae and adults and explored several kinds of mesohabitats and streams. Considering the entire hierarchical model, there was a significant variation in both richness and abundance of the assemblages among the four slopes and between stone and leaf mesohabitats. Moreover, the highest variation in richness and abundance occurred among the samples from the same mesohabitat, which reflects the clumped distribution pattern of the assemblages of Ephemeroptera. Stone was the mesohabitat with the highest estimated richness, similarly Santa Virgínia Nucleus was the slope with highest estimated richness. The ordination showed a trend of segregation of samples from slopes and mesohabitats, this trend was confirmed by multivariate analysis of variance (Permanova). Thus, the spatial structure of the assemblages seems predicted by environmetal factors of local scale related to mesohabitats and the features of regional scale, associated with slopes. The Redundancy Analysis (RDA) showed elevation, electrical conductivity, water temperature and width as the local environmental variables that contributed most to explain the spatial structure of communities. However, local enrironmental factors explained only 19.3% of the data variability, 7.9% of the General Abstract 12 data variability was explained by environmental variables inseparable from the geographical matrix, 23.4% was explained by the geographical location of streams and 49.4% remained unexplained. The results of this study showed the similar contribution of local environmental variables and the geographic location in the community structure, indicating that the biological processes, as dispersal, also influenced the structure of the assemblages of Ephemeroptera larvae.
272

Uso do hábitat pelo boto-cinza Sotalia guianensis (Van Benédén, 1864) (Cetacea: Delphinidae) na Baía de Benevente, ES, Brasil

Stutz Reis, Suzana 01 February 2013 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-03-30T12:40:36Z No. of bitstreams: 1 suzanastutzreis.pdf: 2764480 bytes, checksum: 7958f56283eeeb80e170580b590eda3d (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-04-24T02:51:51Z (GMT) No. of bitstreams: 1 suzanastutzreis.pdf: 2764480 bytes, checksum: 7958f56283eeeb80e170580b590eda3d (MD5) / Made available in DSpace on 2016-04-24T02:51:51Z (GMT). No. of bitstreams: 1 suzanastutzreis.pdf: 2764480 bytes, checksum: 7958f56283eeeb80e170580b590eda3d (MD5) Previous issue date: 2013-02-01 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O uso do hábitat pelos organismos é diretamente influenciado pela disponibilidade dos recursos. Esta disponibilidade é afetada por parâmetros físicos que variam no espaço e no tempo. Assim, a área de vida, a organização social e o comportamento das espécies no ambiente são usualmente determinados pela distribuição em mosaico dos recursos. Diante disto, este estudo visou investigar os descritores bióticos e abióticos explicativos do uso do hábitat pelo boto-cinza (Sotalia guianensis) na Baía de Benevente (ES), e identificar possíveis áreas de ocupação preferencial (hábitats chave). De janeiro a dezembro de 2012 foram realizadas 34 expedições a bordo de duas embarcações - com 4 e 14 metros - e coletou-se diversas variáveis ambientais ao longo de transecções paralelas. A partir de expedições sistemáticas (n=17) e também de oportunísticas (n=17) foram registrados 33 encontros com grupos de botos. Das 142 horas e 3 minutos de esforço amostral, 7 horas e 8 minutos (5,02%) foram de observação direta dos animais. A cada avistagem registrava-se a localização geográfica do agrupamento, seu tamanho e composição, bem como o comportamento. As médias de número de indivíduos e de infantes por grupo foram de 5,24 (±3,25) e 1,03 (±1,29), respectivamente. A análise espacial das avistagens revelou que os encontros ocorreram em 30 (23,44%) das 128 células da malha quadriculada criada no ArcGIS 9.3.1. para representar a área amostrada, evidenciando que a ocupação do hábitat pelos golfinhos não é uniforme (χ2= 22,97; p<0,001). A área utilizada pelos grupos (estimada através de Mínimo Polígono Convexo) foi de 48,14 km2 e representa 39,40% da área estudada (122,18 km2), demonstrando a concentração significativa dos botos em determinadas regiões (χ2= 22,43; p<0,001). Através de modelos lineares generalizados, verificou-se que a distribuição espacial dos botos pode ser explicada pela latitude (regressão GLM, z = 2,57; p<0,02), pela profundidade (regressão GLM, z=2,18; p<0,03) e pela maré enchente (regressão GLM, z=2,39; p<0,02). Em relação às características do grupo, observou-se que o tamanho aumenta em função do oxigênio dissolvido na água (regressão GLM, z=2,08; p<0,04) e da presença de infantes (regressão GLM, z=4,27; p<0,001), enquanto tende a ser menor durante o comportamento de deslocamento (regressão GLM, z=-2,86; p<0,005). Das 6 horas e 26 minutos de atividades dos animais registradas, 46,37% foram despendidas em forrageio/alimentação, 34,20% em deslocamento, 10,62% em descanso e 8,81% em socialização. A latitude na área de estudo tem influência sobre a ocorrência de forrageio/alimentação (regressão GLM, z=2,74; p=0,006) e todos os registros deste comportamento (n=15) ocorreram na porção norte/nordeste da baía. Os grupos de S. guianensis utilizam a baía de forma heterogênea, e sua ocorrência é maior no norte da mesma. Variáveis como latitude, maré, oxigênio dissolvido, presença de infantes e comportamento exercem influência sobre o uso do hábitat pelo boto-cinza neste ambiente. O registro de infantes o ano todo, e a grande proporção de tempo empregado pelos grupos em forrageio/alimentação observada neste estudo indicam que a Baía de Benevente é utilizada por S.guianensis para reprodução e alimentação, demonstrando a relevância deste hábitat para a espécie. / Habitat use by organisms is directly influenced by resources availability. This availability is affected by physical parameters varying through space and time. Thus, home range, social organization and behavior of the species in the environment are usually determined by the mosaic distribution of resources. Given this, this study aimed to investigate the biotic and abiotic descriptors that can be explanatory of habitat use by Guiana dolphins (Sotalia guianensis) in Benevente Bay, Espirito Santo State, Brazil, also to identify possible areas of preferential occupation (key habitats). From January to December, 2012 we carried out 34 surveys using 4 or 14 meters boats, and measured environmental variables along parallel transects. From the systematic (n = 17) and opportunistic surveys (n = 17) we sighted 33 groups of dolphins. The survey effort was of 142 hours and 3 minutes, comprising 7 hours and 8 minutes (5.02%) of direct observation of the animals. For each sighting, it was recorded the group’s geographical position, size, composition and behavior. The average number of individuals and infants per group were 5.24 (± 3.25) and 1.03 (± 1.29), respectively. Spatial analysis revealed that encounters occurred in 30 (23.44%) out of the 128 cells of the grid created using ArcGIS 9.3.1. to represent the sampled area, evidencing that habitat occupation by dolphins is not uniform (χ2 = 22.97, p<0.001). The area used by groups (estimated through Minimum Convex Polygon) was 48.14 km2, which represents 39.40% of the studied area (122.18 km2) and demonstrated the significant concentration of dolphins in certain regions (χ2 = 22.43, p<0.001). Generalized linear models applied to the data showed that Guiana dolphin’s spatial distribution can be explained by latitude (GLM regression, z = 2.57, p<0.02), depth (GLM regression, z = 2.18, p<0.03) and flood tide (GLM regression, z = 2.39, p<0.02). Regarding to the group characterization, we observed that its size increases as a function both of dissolved oxygen in the water (GLM regression, z = 2.08, p<0.04) and infants presence (GLM regression, z = 4.27, p<0.001), unlike it tends to decrease during displacement activities by the dolphins (GLM regression, z = -2.86, p <0.005). From 6 hours and 26 minutes of behaviors counted, 46.37% were spent by animals on foraging/feeding, 34.20% in travelling, 10.62% in resting and 8.81% in socializing. The latitude in the study area has influence on the occurrence of foraging/feeding (GLM regression, z = 2.74, p = 0.006) and all records of this behavior (n = 15) occurred at bay’s northern/northeastern sectors. The spatial use was heterogeneous and the occurrence of groups concentrated in the north of the area. Some variables as latitude, tide, dissolved oxygen, infants presence and behavior are likely to influence the habitat use of the Guiana dolphin in this environment. The presence of infants throughout the year, coupled with the proportion of time spent by the groups in foraging/feeding observed in this study indicate that Benevente Bay has been used by Guiana dolphin for breeding and feeding, and demonstrate the importance of this habitat for the species.
273

Dinâmica demográfica e indicadores socioeconômicos em escala intramunicipal na fronteira : municípios de Altamira e São Félix do Xingu, Estado do Pará, entre 2000 e 2010 / Population dynamics and socioeconomic indicators in intramunicipal scale : municipalities of Altamira and São Félix do Xingu, Pará State, between 2000 and 2010

Dagnino, Ricardo de Sampaio, 1976- 06 May 2014 (has links)
Orientador: Roberto Luiz do Carmo / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-25T21:00:48Z (GMT). No. of bitstreams: 1 Dagnino_RicardodeSampaio_D.pdf: 7937136 bytes, checksum: 6a0151992bf83608f9216004e0e75f76 (MD5) Previous issue date: 2014 / Resumo: Este trabalho trata das diferenças socioeconômicas existentes no interior dos municípios de Altamira e São Félix do Xingu (PA), situados na fronteira de expansão amazônica. A metodologia desenvolvida compreende três procedimentos. O primeiro, de aquisição da informação, foi a construção de 52 indicadores socioeconômicos (taxa de analfabetismo, renda, etc.) e demográficos (estrutura etária, razão de sexos, etc.) referidos ao nível intramunicipal. A fonte utilizada foram os Censos Demográficos de 2000 e 2010 e a Contagem de População 2007, do Instituto Brasileiro de Geografia e Estatística (IBGE), que apresentam dados agregados por setores censitários (que totalizavam 154 em 2000 e 315 em 2010), que é a menor unidade de representação dos dados. O segundo procedimento, já de tratamento da informação, foi a definição de 29 unidades espaciais intra e trans municipais mediante o agrupamento dos setores censitários de acordo com sua situação (rural e urbana), categoria de localidade (povoado, vila, cidade, etc.) e critérios que garantam o acompanhamento de sua trajetória temporal (2000 a 2010). O terceiro, apoiado nas matrizes ponderadas e permutáveis de Bertin, permite o cruzamento dos 52 indicadores com as 29 unidades espaciais, e levou à construção de 11 agrupamentos dessas unidades, possibilitando a verificação de diferenças (e semelhanças) socioeconômicas entre eles. Dado que objeto de análise concebido pela metodologia é o espaço intramunicipal, torna-se possível captar diferenças socioeconômicas existentes entre: (1) unidades espaciais urbanas e rurais; (2) unidades espaciais urbanas da mesma categoria; (3) unidades rurais situadas dentro e fora de áreas protegidas; (4) unidades rurais situadas nos dois tipos de áreas protegidas (terras indígenas e unidades de conservação). Os resultados obtidos permitem análises de tipo sincrônico, através de comparações entre indicadores de distintos agrupamentos no mesmo ano e explicitam correlações entre indicadores relativos a um mesmo agrupamento, como renda e analfabetismo; e diacrônico, que possibilitam avaliar e correlacionar a evolução temporal de distintos indicadores do mesmo agrupamento. Num plano mais genérico, considera-se que as características da metodologia desenvolvida tornam possível seu emprego para avaliar diferenças socioeconômicas existentes entre agregados populacionais selecionados segundo critérios de distintas naturezas (administrativa, ambiental, social, entre outras possibilidades) / Abstract: This works deals with the internal socioeconomic differences on the municipalities of Altamira and São Félix do Xingu, Pará state, situated on the frontier expansion of Amazonia The methodology comprises three procedures. The first, acquiring information, was the construction of 52 socioeconomic indicators (illiteracy, income, etc.) and demographic indicators (age structure, sex ratio, etc.) referred to intra-municipal level. The source used was the Demographic Census of 2000 and 2010 and the 2007 Population Count, by the Brazilian Institute of Geography and Statistics (IBGE), that present data aggregated by census tracts (between 100 and 300, depending on the year), which is the smallest unit data representation. The second procedure, processing information, was the definition of 29 intra and trans municipal spatial units by grouping census tracts according to their situation (rural and urban) and type of locality (village, town, city, etc.) and criteria that enable the monitoring of its temporal trajectory (2000-2010). The third, supported by the Bertin's "weighted and exchangeable matrix", permitting the "cross" of the 52 indicators with 29 spatial units, led to the construction of 11 units of these clusters, allowing the verification of socioeconomical differences (and similarities) between them. Since the object of analysis, designed by the methodology, is intramunicpal space, it becomes possible to capture existing socioeconomic differences between: (1) urban and rural spatial units; (2) urban spatial units of the same type; (3) rural units located within and outside protected areas; and (4) rural units located in two types of protected areas (indigenous lands and conservation units). The results obtained allows synchronic analysis, by comparing between indicators of different classes in the same year and explain correlations between indicators of the same group, such as income and illiteracy; and diachronic, in order to assess and correlate the temporal evolution of different indicators in the same group and the same indicator for the different groups. On a more general level, it is considered that the characteristics of the developed methodology make its use possible to evaluate existing socioeconomic differences among population clusters that transcend municipal division designed according to criteria of different natures / Doutorado / Demografia / Doutor em Demografia
274

Mobilidade e distribuição populacional em Santarém, Pará = recente reconfiguração do meio rural na Amazônia / Population mobility and distribution in Santarém, Pará : the recent reconfiguration of rural areas in the Amazon

Côrtes, Julia Correa, 1983- 19 August 2018 (has links)
Orientador: Álvaro de Oliveira D'Antona / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-19T23:19:01Z (GMT). No. of bitstreams: 1 Cortes_JuliaCorrea_M.pdf: 13996086 bytes, checksum: 16aca3ca2ed811d76fedb07c9c430380 (MD5) Previous issue date: 2012 / Resumo: Modelos explicativos sobre dinâmica populacional e mudança no uso e cobertura da terra na Amazônia não são suficientes para explicar a recente reconfiguração do espaço rural. As principais teorias são embasadas nos movimentos clássicos de regiões de fronteira agrícola, com o cenário de êxodo da população, chegada da agricultura capitalizada, expansão do desmatamento e expansão urbana. Confrontando a limitação das referências teóricas, estudou-se a recente mobilidade e distribuição da população no município de Santarém, focalizando na sua relação com a urbanização do rural como parte da mudança do uso da terra. Foram utilizados os Censos Demográficos 2000 e 2010, além de levantamentos sociodemográficos em 587 estabelecimentos familiares na região rural de Santarém, realizados em 2003 e 2009. Análises espaciais foram realizadas com dados do IBGE por setores censitários de Santarém e com desenhos das propriedades visitadas em campo. Os resultados apontaram para a existência de um conjunto muito maior de possibilidades de mobilidade populacional, que não a saída do rural e o deslocamento para novas fronteiras ou centros urbanos. A redistribuição da população no mesmo espaço rural provou ser um fenômeno importante, relacionando-se a novos arranjos populacionais no espaço e a um distinto padrão fundiário. Fluxos e padrões ausentes nas explicações regionais foram constatdos no estudo, como o deslocamento a partir de áreas urbanas à propriedades rurais e como o arrefecimento da emigração de mulheres jovens. O uso de fontes mistas, com perspectivas escalares diferentes, foi essencial para compreender o quadro da transformação rural de maneira mais completa. Novas feições espaciais foram aludidas, mostrando que a população se reorganiza no espaço intramunicipal através de dinâmicas familiares ou pessoais. O conjunto de fluxos populacionais, dinâmicas domiciliares e relações familiares promove a transformação do rural pelo resultado deste processo histórico de ocupação, alterando o quadro fundiário e sociológico dessas áreas. Microrregiões com mosaico de pequenas propriedades, infra-estrutura, áreas comunitárias e serviços comerciais configuram a urbanização rural. A ampliação das categorias usadas nos estudos de mudança da terra, com a inclusão deste processo, promove uma discussão mais coerente com a recente reconfiguração de áreas rurais na Amazônia / Abstract: The current models used to explain the relation between population dynamics and land use and cover change in the Amazon region are not sufficient to elucidate the recent reconfiguration of rural areas. The major theories are grounded in the classical movement of agricultural frontier, which includes exodus of the population, arrival of capitalized agriculture, deforestation expansion and urban sprawl. To overcome the shortcomings of these classical theories, the goal of this work is study the recent mobility and population distribution in the municipality of Santarém, focusing on the relationship between population dynamics and the rural urbanization as part of the land use change. Data were extracted from the Brazilian Demographic Census 2000 and 2010, and from a set of sociodemographic surveys applied in 587 familiar rural properties in 2003 and 2009. Spatial analyzes were performed by IBGE data in Santarem and the croquis of the farms visited in the field. The results showed that are many other components contributing to population mobility besides rural exodus and moviment to new frontiers or urban centers. The redistribution of population in the same rural areas proved to be an important phenomenon explaining the changes in spatial arrangement of population and land properties. Flows and patterns, which are absent in regional explanations, were found in this study, such as the shift from urban to rural properties and the reduction of the young women emigration. The use of mixed sources with different scale perspectives was crucial to understand the context of rural transformation more fully. New spatial pattern of population distribution was found as a result of the population reorganization, which was greatly influenced by ties established between family members. Within a sociological context, population mobility, household dynamics and family relationships modify the land structure and therefore lead to rural transformation. The history of population occupation creates a small region with a mosaic of properties of different sizes, infrastructure, commercial areas and community services. This process result in the rural urbanization. The study of population dynamics and rural configuration in the Amazon region will most likely advance as other components of human mobility are taken into consideration / Mestrado / Demografia / Mestre em Demografia
275

Avaliação da ocorrência de seca no estado do Rio Grande do Sul / Evaluation of drought occurrence in the state of Rio Grande do Sul

Silva, Gisele Machado da Silva 31 March 2015 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2017-03-07T16:57:14Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) DISSERTAÇÃO_Gisele_Machado.pdf: 3307276 bytes, checksum: 592c96eced3ac21eaba699361b81eed0 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-03-09T20:39:48Z (GMT) No. of bitstreams: 2 DISSERTAÇÃO_Gisele_Machado.pdf: 3307276 bytes, checksum: 592c96eced3ac21eaba699361b81eed0 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-09T20:39:48Z (GMT). No. of bitstreams: 2 DISSERTAÇÃO_Gisele_Machado.pdf: 3307276 bytes, checksum: 592c96eced3ac21eaba699361b81eed0 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-03-31 / O Estado do Rio Grande do Sul tem acumulado perdas na produção agropecuária e econômica, em função da ocorrência de eventos de seca. Apesar de todo o avanço tecnológico, a agricultura ainda depende das condições climáticas e meteorológicas e, por isso, estudos devem ser realizados com o intuito de auxiliar na investigação do comportamento da seca, nas mais diversas regiões. Um passo importante para o entendimento dos eventos de seca é a utilização de índices, que fazem um levantamento da situação, conforme uma escala de intensidade, que objetiva dar um panorama do comportamento hídrico da região.Assim, o presente trabalho tem como objetivo identificar e caracterizar o comportamento da seca, utilizando índices meteorológicos, em diferentes escalas temporais para 40 estações, compostas por uma série de dados de precipitação de 90 anos (1913-2002), localizadas no Estado do Rio Grande do Sul, obtidas através do banco de dados do Instituto Nacional de Meteorologia e da Agência Nacional de Águas.Para tanto, foram utilizados dois índices de seca: Índice Padronizado de Precipitação, nas escalas temporais de 1, 3, 6, 9, 12 e 24 meses, nas intensidades severa e extrema,e o Índice de Moreno,em escala trimestral e semestral,nas intensidades intensa e severa, bem como a contagem do número total de dias secos e análise da sequência de dias secos.Para o preenchimento de dados das séries de precipitação diária, foi utilizada a modelagem estocástica Cadeia de Markov de dois estados. Os resultados mostraram que para o Índice de Moreno, a escala trimestral, comparativamente à escala semestral, apresentou maior concentração de eventos de seca. Para o Índice Padronizado de Precipitação,as maiores sequências de meses secos foram encontradas na intensidade extrema; a maior ocorrência de eventos de seca severa coincidiu em 85% com os períodos de La Niña e a maior incidência de eventos de seca severa e intensa ocorreu na década de 1943 a 1952. Quantoà espacialização do Índice Padronizado de Precipitação, nas escalas 6, 12 e 24 meses, esta representou adequadamente os resultados obtidos nas sequências de períodos secos. / Due to the occurrence of drought events, the state of Rio Grande do Sul has accumulated losses in the agricultural and economic production. Despite the technological advances, agriculture still depends on climatic and weather conditions and, therefore, studies should be conducted in order to help the investigation of drought behavior in various regions. An important step in the understanding of drought events is the use of indexes, which survey the situation, according to an intensity scale, which aims to give an overview of the water behavior in the region. Thus, this study aims to identify and characterize drought behavior by using meteorological indexes, at different time scales for 40 seasons, consisting of a series of rainfall data from 1913 to 2002, located in the state of Rio Grande do Sul, obtained from the database of the National Institute of Meteorology (INMET) and the National Water Agency (ANA). Therefore, two drought indexes were used: Standardized Precipitation Index, in the time scales of 1, 3, 6, 9, 12 and 24 months, in severe and extreme intensities, and the Moreno Index, a quarterly and half-yearly scale, in intense to severe intensities, as well as the count of the total number and sequence analysis of dry days. For data filling of daily precipitation series, the stochastic model was used applying the Markov chain from two states. The results indicated that for the Moreno Index, the quarterly level, compared to the half-yearly scale, showed a higher concentration of drought events. For the Standardized Precipitation Index, the main sequences of dry months were found in extreme intensity; the higher incidence of severe drought events coincided in 85% with periods of La Niña and the higher incidence of severe and intense drought events occurred from 1943 to 1952. As for the spatial distribution of the Standardized Precipitation Index, in the scales 6, 12 and 24 months, it adequately represented the results obtained in the sequences of dry periods.
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Facteurs explicatifs de la répartition spatiale en Afrique australe de deux espèces de tiques parapatriques, vectrices de la cowdriose, Amblyomma variegatum et Amblyomma hebraeum et rôle de la compétition / Spatial distribution of the explanatory factors in Southern Africa Two tick species parapatric vector of heartwater , Amblyomma variegatum and Amblyomma hebraeum and role of competition

Bournez, Laure 25 April 2014 (has links)
La connaissance des facteurs qui influent sur les populations de tiques et en particulier sur leurs distributions est un préalable indispensable à l’étude des maladies qu’elles transmettent. Parmi eux, l’importance des facteurs biotiques et en particulier celle de la compétition interspécifique est peu connue et souvent négligée. L’objectif de ce travail était d’évaluer le rôle de la compétition interspécifique sur la distribution de deux espèces de tiques d’importance vétérinaire, Amblyomma variegatum et A. hebraeum. Alors que seule A. variegatum favorise la transmission de la dermatophilose, une maladie de peau débilitante pour les ruminants, les deux espèces sont vectrices de la cowdriose, maladie due à une bactérie Ehrlichia ruminantium qui représente une contrainte économique majeure pour l’élevage. L’impact de l’espèce vectrice dans l’épidémiologie de la cowdriose (différences de souches circulantes, sévérité des cas,…) est inconnu bien qu’ayant potentiellement des conséquences en termes de surveillance (risque épidémiologique à l’introduction d’animaux) et de contrôle (développement de vaccin régional adapté aux souches circulantes) de la maladie. Ces deux espèces ont une distribution contiguë en Afrique australe avec peu de chevauchement (distribution parapatrique) suggérant une préférence environnementale différentielle ou une compétition exclusive entre elles. Une revue des données de la littérature a permis de mettre en évidence un chevauchement de leur niche trophique, climatique, et temporelle, et une interférence comportementale via la production de leurs phéromones. Les deux espèces pourraient donc rentrer en compétition directement par interférence communicative ou reproductive (hybridation stérile), ou indirectement via le partage de ressources, prédateurs ou pathogènes communs. Le rôle des facteurs biotiques et abiotiques sur le maintien de la parapatrie de ces deux espèces a été analysée (i) d’une part par la comparaison de leur niche environnementale réalisée en Afrique australe, et aux deux zones de contact au Zimbabwe et Mozambique, par des méthodes d’ordination et de modèles de niche (Maxent) ; (ii) et d’autre part par l’étude de leurs distributions et de leurs interactions (distribution sur les hôtes, croisements hétérospécifiques) dans la zone de contact au Mozambique. Globalement les résultats montrent qu’en Afrique Sud-Est et au Zimbabwe les deux espèces occupent des niches environnementales distinctes, celle d’A. hebraeum incluant des zones plus chaudes et plus sèches que celle d’A. variegatum. Au contraire au Mozambique les deux niches se chevauchent considérablement. L’enquête de terrain dans cette zone montre que les deux espèces y sont moins souvent trouvées en sympatrie que les données prédites, suggérant une distribution en partie déterminée par des interactions biotiques. Dans les rares sites avec présence des deux espèces, A. variegatum et A. hebraeum partagent les mêmes sites de fixation sur les animaux et forment un pourcentage relativement élevé de couples hétérospécifiques. Ce pourcentage, bien que similaire entre les femelles A. variegatum et A. hebraeum, semble impliquer des processus de discrimination spécifique propres aux deux espèces intervenant au niveau de l’agrégation, de la fixation et du contact des individus. Nos résultats suggèrent l’existence d’une compétition exclusive entre les deux espèces, due à une compétition sexuelle probablement associée à une compétition indirecte. La frontière parapatrique semble occuper une position stable le long d’un gradient environnemental au Zimbabwe mais pas au Mozambique. Les conditions entrainant la coexistence ou l’exclusion des deux espèces avec formation d’une frontière parapatrique sont discutés à l’aide de modèles théoriques de compétition. / Studying the factors that influence tick populations and their distributions is an essential pre-requisite to understanding the dynamics of the diseases they transmit. The relative importance of biotic factors such as interspecific competition is not well known and often neglected. The objective of this study was to assess the influence of interspecific competition on the distribution of two tick species of veterinary importance, Amblyomma variegatum and A. hebraeum. Whereas only A. variegatum is known to favor dermatophilosis, a debilitating skin disease of ruminants, both species are good vectors of Ehrlichia ruminantium, the bacteria causing heartwater, a fatal disease of ruminants that presents a major constraint for livestock development in Africa. The impact of vector species in heartwater epidemiology (differences of circulating strains, severity of clinical cases…) is poorly known but may have important implications for surveillance (epidemiological risk of imported animals) and control (adapting regional vaccine programs to circulating strains) of the disease. These two ticks have abutting and marginally overlapping (i.e. parapatric) distributions in southern Africa, suggesting either differential environmental preferences or exclusive competition between the two species. A review of published data highlighted an important overlap of their trophic, climatic and seasonal niche, and existence of chemical behavior interference through pheromone production. Therefore, the two species might compete either directly by communicative or reproductive interference (sterile hybridization), or indirectly by sharing the same resources, predators or pathogens. The role of biotic and abiotic factors in determining parapatry of these species was assessed by (i) comparing their realized environmental niche in southern Africa, and at contact zones in Zimbabwe and Mozambique, using ordination techniques and environmental niche modeling (Maxent); (ii) studying their distributions and their interactions (distribution on co-infested host, heterospecific mating) at the contact zone in Mozambique. Globally, the results indicated the two species occupied distinctly different environmental niches in southern Africa and at the contact zone in Zimbabwe, with the niche of A. hebraeum including both hotter and drier areas than that of A. variegatum. However, in Mozambique their niches overlapped considerably. Field studies within this zone showed that sympatry was observed less frequently than predicted by niche models, suggesting an importance of biotic interactions. At the rare sites where both species were present, A. variegatum and A. hebraeum were observed to share the same preference sites on hosts and formed a high percentage of heterospecific pairs. Though this cross-mating rate was not significantly different between A. variegatum and A. hebraeum females, our observations suggest different mechanism of species discrimination involved for the two species acting at the aggregation, fixation and partner contact level. Our results strongly suggest exclusive competition between these species may arise from sexual competition probably interacting with other indirect forms of competition. The parapatric boundary apparently occupies a stable location along an environmental gradient at the contact zone in Zimbabwe but not in Mozambique. Conditions inducing coexistence or exclusion of both species with the formation of parapatric distributions are discussed in relation to theoretical models of competition. When sexual competition is introduced in these models, the relative frequency of two species is determined by their endogenous fitness (a function of environmental conditions), density dependent effects of competitive interactions, historical distributions and dispersal rates: survival of the first prevails when the immigration rate of a fitter invading species remains lower than an invasion threshold.
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Distribution de l'or de type orogénique le long de grands couloirs de déformation archéens : modélisation numérique sur l'exemple de la ceinture de l'Abitibi / Orogenic type gold distribution along major archean fault zones : numerical modelling in the Abitibi Belt

Rabeau, Olivier 09 November 2009 (has links)
Cette thèse visait à mieux définir les méthodes de ciblage et apporter des éléments de réponse sur la genèse des gisements d’or de type orogénique en périphérie des grands couloirs de déformation archéens. Cette thèse est présentée sous forme de trois articles. Le premier article traite de la distribution mathématique des gisements aurifères de type orogénique le long des grands couloirs de déformation. Une approche permettant de d’établir que la localisation des gisements se situant le long de structure de premier ordre n’est pas indépendante de la localisation de ses voisins a été développée. Cette approche permet de donner des éléments de réponse sur la formation de ces gisements et de générer des probabilités de découvertes à l’échelle régionale. La deuxième partie de cette présente une méthode l’évaluation du potentiel minéral sous couverture sédimentaire en 3D. Les teneurs aurifères compilées dans le secteur ont permis d’évaluer et de quantifier les relations spatiales existantes entre certaines entités géologiques et les emplacements minéralisés afin de cibler les endroits à haut potentiel. Enfin, les travaux présentés dans le dernier chapitre visent à délimiter les zones possédant une perméabilité structurale accrue lors de l’épisode de déformation contemporain à la mise en place de gisements aurifères de type orogénique. Une modélisation géomécanique 3D qui tient compte des propriétés physiques des roches a été effectuée sur un segment de faille choisi en utilisant un code d’élément fini. La déformation s’effectue en attribuant sur chaque discontinuité structurale des vecteurs ou des champs de déplacement en fonction des observations de terrain / This thesis had the objective to define targeting methods adapted to orogenic gold deposits hosted in greenstone belts and to better understand the formation mechanism of these deposits. The work accomplished is presented in three distinct articles. The first article aimed to determine if a mathematical relation can characterize the spatial distribution of orogenic gold deposits along a crustal scale fault zone within or if the localization of a deposit is independent of the position of each other. A uniform law was fitted between the frequency and the curvilinear inter-distance between successive orogenic gold occurrences along the CLLF for distances ranging from 315 to 5600 m. This approach gave insights on the formation mechanism and allowed the generation of a probability map for undiscovered deposits at a regional scale. The second chapter of this thesis focuses on a sector of the Cadillac Larder Lake Fault that was considered as having a high potential for discovery using the methodology presented in the last chapter. Compiled assays allowed the evaluation of the spatial association of certain geological features with orogenic gold mineralizations to allow targeting high potential areas. Finally, the work presented in the last chapter aimed at identifying dilatant zones during the deformation that is contemporaneous to the orogenic gold deposit formation. A 3D geomechanical modelling which takes rock properties into account was performed on a chosen segment of a fault zone using a finite element code. The deformation was induced using displacement vectors or fields interpreted from field data
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Fine-Scale Structure Of The Diurnal Cycle Of Global Tropical Rainfall

Chattopadhyay, Bodhisattwa 08 1900 (has links) (PDF)
The fine-scale structure of global (30N-30S) tropical rainfall is characterised using 13 years (1998-2010) of 3-hourly and daily, 0.25-degree Tropical Rainfall Measuring Mission (TRMM) 3B42 rainfall product. At the outset, the dominant timescales present in rainfall are identified. Specifically, the Fourier spectrum (in time) is estimated in two ways (a) spectrum of spatially averaged (SoSA) rainfall; and (b) spatial average of the spectrum (SAoS) of rainfall at each grid point. This procedure is applied on rainfall at the 3-hourly and daily temporal resolutions. Both estimates of the spectrum show the presence of a very strong seasonal cycle. But, at subseasonal timescales, the two methods of estimating spectrum show a marked difference in daily rainfall. Specifically, with SoSA the variability peaks at a subseasonal timescale of around 5 days, with a possible secondary peak around 30-40 days (mostly in the southern tropics). With SAoS, the variability is distributed across a range of timescales, from 2 days to 90 days. However, with finer resolution (3-hourly) observations, it is seen that (besides the seasonal cycle) both methods agree and yield a dominant diurnal scale. Along with other subseasonal scales, the contribution and geographical distribution of diurnal scale variability is estimated and shown to be highly significant. Given its large contribution to the variability of tropical rainfall, the diurnal cycle is extracted by means of a Fourier-based filtering and analysed. The diurnal rainfall anomaly is constructed by eliminating all timescales larger than 1 day. Following this, taking care to avoid spurious peaks associated with Gibbs oscillations, the time of day (called the peak octet) when the diurnal anomaly is largest is identified. The peak octet is estimated for each location in the global tropics. This is repeated for 13 years, and the resulting mode of the time of maximum rainfall is established. It is seen that (i) most land regions receive rainfall during the late afternoon/early evening hours; (ii) rainfall over open oceans lack a dominant diurnal signature with a possible combination of early morning and afternoon showers; (iii) coastal regions show a clear south/southwest propagation in the mode of the peak octet of rainfall. In addition to being a comprehensive documentation of the diurnal cycle at very fine scales, the results serve as a critical test for the validation of theoretical and numerical models of global tropical rainfall.
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Direções da Segregação Socioespacial na Região Metropolitana de Campinas : uma abordagem sociodemográfica a partir dos censos 2000 e 2010 / Directions of Socio-Spatial Segregation in the Metropolitan Region of Campinas : a sociodemographic approach from the 2000 and 2010 censuses

Mello, Camila Canuto Dias de, 1981- 11 May 2013 (has links)
Orientadores: Alberto Augusto Eichman Jakob, José Marcos Pinto da Cunha / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-24T11:21:46Z (GMT). No. of bitstreams: 1 Mello_CamilaCanutoDiasde_M.pdf: 3313963 bytes, checksum: 9cdec82646e4d1a96c88a1ef66950cf3 (MD5) Previous issue date: 2013 / Resumo: Em estudos urbanos o termo "segregação" geralmente é utilizado na tentativa de explicar e verificar a existência da separação e concentração de grupos sociais em determinadas áreas das cidades. Uma maneira usual de abordar a segregação é a que considera o caráter socioeconômico, dos grupos sociais e sua distribuição espacial. Esta forma é a que comumente caracteriza a estruturação das nossas metrópoles. A forma de alocação das camadas populacionais de altos rendimentos acaba por forçar a os grupos populacionais de menor renda a localizar-se em outras áreas dos espaços intraurbanos. Dessa forma, procurou-se conhecer, as direções para onde se expande a região, e de que forma o espaço metropolitano vai sendo apropriado por uns e imposto a outros, criando o que se chama de segregação socioespacial. Parte-se da discussão em torno da relação entre as alterações populacionais e influência nos padrões de segregação socioespacial / Abstract: In urban studies the term "segregation" is usually used in an attempt to explain and verify the existence of the separation and concentration of social groups in certain areas of cities. A common way to approach is the segregation that considers the socioeconomic character of social groups and their spatial distribution. This form is that commonly characterizes the structure of our cities. The form of allocation of fish layers of high yields eventually force the lower income population groups to be located in other areas of intraurbanos spaces. Thus, we sought to know the directions to the region expands, and how the metropolitan space will be appropriate for a tax and the other, creating what is called a sociospatial segregation. Part of the discussion was around the relationship between population change and influence on patterns of socio-spatial segregation / Mestrado / Demografia / Mestra em Demografia
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Estudo dos indivíduos heterozigotos para doença falciforme identificados na triagem neonatal em Sergipe

Leite, Débora Cristina Fontes 27 July 2016 (has links)
Hemoglobinopathies are genetic alterations of high population frequency. Neonatal screening identified both homozygous cases (patients) and heterozygotes (sound carriers). This study aims to identify the spatial distribution of the HbS carriers (SCT) in Sergipe from universal newborn screening and evaluate knowledge about hemoglobinopathies in heterozygous families for genetic counseling performed in the delivery of the results of neonatal screening. The sample consisted of all individuals born in Sergipe, from October 2011 to October 2012, that have been submitted to neonatal screening by the National Health System. Tests were carried out in basic health units and forwarded to the University Hospital Lab where they were analyzed. The relatives of patients with SCT were called to attend the meeting where the delivery of the examination was made, and answered the questionnaire on knowledge of sickle cell disease and trait, before and after orientation. Analysis of the spatial distribution of individuals heterozygous for hemoglobinopathies was performed using spatial autocorrelation (Moran index). To evaluate the number of total hits questionnaire before and after we used the Wilcoxon test and each question was performed McNemar test. Among the 32,906 examinations, 1,202 showed abnormalities standard hemoglobin. There was a positive correlation with the percentage of blacks and mulattos county and the incidence of SCT and a negative correlation with the percentage of blacks in the cities. In heterozygous distribution analysis of the state of Sergipe conducted by autocorrelation were identifying three regions in the state more frequently to HbS. Of the 1,202 individuals identified with SCT only 290 families attended the genetic counseling. The knowledge of the study population regarding hemoglobinopathies are limited. Even though the need for neonatal screening, the majority of respondents is unaware of what the diseases surveyed by examination. However, they managed to assimilate information with the strategy used. / As hemoglobinopatias são alterações genéticas de alta frequência populacional. Com a triagem neonatal identificamos tanto os casos homozigotos (doentes), quanto os heterozigotos (portador sadio). O presente estudo tem como objetivo identificar a distribuição espacial da presença do portador de Hemoglobina S (HbS) em Sergipe a partir da triagem neonatal universal e avaliar o conhecimento a respeito das hemoglobinopatias, nos familiares dos lactentes heterozigotos identificados na triagem neonatal durante orientação genética realizada na entrega dos resultados do exame. A amostra estudada constituiu-se de todos os indivíduos nascidos em Sergipe, de outubro de 2011 a outubro de 2012, e que tenham sido submetidos à triagem neonatal pelo Sistema Único de Saúde. A coleta dos exames foi realizada nas unidades básicas de saúde e encaminhadas ao Laboratório do Hospital Universitário onde foram analisadas. Os familiares de pacientes com traço falciforme (TF) eram convocados a participar de uma reunião, onde foi realizada a entrega do exame, e aplicado questionário sobre o conhecimento da doença e TF antes e após a orientação. A análise da distribuição espacial dos indivíduos heterozigotos para HbS foi realizada através autocorrelação espacial (Índice de Moran). Para avaliação do conhecimento sobre as hemoglobinopatias, o número de acertos total do questionário antes e após foi utilizado o teste de Wilcoxon e cada questão foi realizado o teste de Mc Nemar. Dentre os 32.906 exames realizados, 1.202 apresentaram alguma alteração do padrão da hemoglobina. Observou-se correlação positiva entre o percentual de negros e pardos dos municípios e a incidência de TF, mas correlação negativa quando apenas o percentual de negros era considerado. Na análise da distribuição de heterozigotos no estado de Sergipe, realizada pela autocorrelação foram identificadas 3 regiões no estado com maior frequência da HbS. Dos 1.202 indivíduos identificados com TF apenas 290 familiares compareceram à orientação genética. O conhecimento da população estudada a respeito das hemoglobinopatias foi limitado. Mesmo sabendo da necessidade de realização da triagem neonatal, grande parte dos entrevistados desconhece quais são as doenças pesquisadas pelo exame. Entretanto, conseguiram assimilar informações com a estratégia utilizada.

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