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Padrões espaciais de localização dos empreendimentos do Programa Minha Casa Minha Vida : impactos na qualidade da habitação social e satisfação dos moradoresLima, Marcia Azevedo de January 2016 (has links)
O trabalho trata da avaliação da qualidade da produção do Programa Minha Casa Minha Vida na Região Metropolitana de Porto Alegre, na busca de subsídios para a produção da habitação social. Primeiramente, foi investigado se existem padrões espaciais de localização diferenciados para as Faixas de renda 1, 2 e 3, que poderiam gerar diferentes níveis de integração do conjunto no tecido urbano consolidado. A partir da identificação dos padrões espaciais de localização, foi verificada a existência de relação desses padrões com as diretrizes da política urbana em nível local, expressas através da regulação urbanística, propiciando localizações mais adequadas para a habitação de interesse social. Ainda, teve o objetivo de averiguar se o modelo de cidade (estrutura do espaço urbano) que está sendo produzido pelo Programa MCMV na RMPA apresentou avanços em relação à produção habitacional do BNH (Banco Nacional de Habitação), no tocante aos padrões espaciais de localização dos empreendimentos. A seguir, foram analisados se os padrões espaciais de localização geram impactos sobre as condições de mobilidade e de acesso a oportunidades de desenvolvimento humano e econômico e afetam os níveis de satisfação dos moradores com o desempenho dos conjuntos. Os procedimentos metodológicos adotados incluem múltiplos métodos de coleta de dados e análises que possibilitaram complementariedade entre os dados obtidos através de levantamento de arquivo, levantamento físico e aplicação de questionários. A análise estatística dos dados quantitativos foi realizada através da verificação das frequências e realização de testes não-paramétricos, como Kruskal-Wallis e Spearman. Foi utilizada a análise sintática para medir os níveis de integração. Os resultados obtidos confirmam que a produção do Programa Minha Casa Minha Vida apresenta um padrão espacial de localização, especialmente para a Faixa 1, com empreendimentos de médio e grande porte, distantes do centro urbano consolidado e segregados do entorno. As localizações dos empreendimentos da Faixas 2 e 3 são bastante similares, porém um pouco melhores do que as localizações dos empreendimentos da Faixa 1, que tendem promover diferentes níveis de satisfação com o desempenho dos conjuntos e diferentes impactos sobre a qualidade de vida dos moradores. Finalmente, é possível concluir que o padrão de localização dos empreendimentos do Programa MCMV na Região Metropolitana de Porto Alegre parece não apresentar avanços em relação à produção habitacional do BNH e é ressaltada a importância de avaliar os impactos da localização de conjuntos habitacionais na satisfação geral dos moradores, na busca da produção de espaços residenciais qualificados que contribuam para a sustentabilidade urbana. / The study deals with quality evaluation of the housing program “Minha Casa Minha Vida” (MCMV) implemented in the Metropolitan Region of Porto Alegre, in order to subsidize the social housing production. Firstly, it aimed at investigate if there are different patterns of spatial location according to income groups 1, 2 and 3, which might generate different levels of integration of the housing scheme in the consolidated urban grid. Secondly, it was verified whether the location patterns are related to urban legislation at local level, incorporated in the urban regulation and resulting in locations that are more appropriate to social housing production. Moreover, it was intended to explore if the structure of the urban space produced by the Program MCMV in the Metropolitan Region of Porto Alegre showed improvements in relation to social housing produced by the National Housing Bank (BNH), considering spatial patterns of location of the housing schemes. Following, the patterns of spatial location were analyzed in order to test their impacts on the conditions of mobility and access to human and economic development opportunities that affect the level of resident satisfaction with the performance of housing schemes. Methodological procedures included multiple methods of data collection and analysis which enabled complementarities between the data obtained through archive information, physical measurements and questionnaires. The statistical analysis of quantitative data was carried out by means of frequencies and non-parametric tests such as Kruskal-Wallis and Spearman correlations. Spatial syntax analysis was used in order to measure levels of integration. Results confirm the existence of patterns of location, especially for the lowest income group, with large and medium size housing schemes distant from the consolidated urban area and segregated from its surroundings. The location of housing schemes for income groups 2 and 3 are similar, but slightly better than the locations of housing schemes for income group 1, which tend to promote different levels of resident satisfaction with the performance of the housing schemes and different impacts on their quality of life. Finally, it was possible to conclude that the patterns of location of the housing schemes produced in the Program MCMV in the Metropolitan Region of Porto Alegre did not improve in relation to social housing produced by the National Housing Bank (BNH) and highlights the importance of assessing the impacts of location of housing schemes on the overall residents satisfaction, in order to produce more qualified residential spaces that promote urban sustainability.
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Neolithic Fisheries : Osteoarchaeology of Fish Remains in the Baltic Sea RegionOlson, Carina January 2008 (has links)
<p>The variety of fish species found at the archaeological sites indicates the exploitation of local and regional ecosystems. The focus of the fisheries varies from site to site. </p><p> The study is based on the analyses of faunal materials from 10 archaeological sites from Eastern Middle Sweden, Gotland, and Åland dating to approximately 3800 – 1850 B.C. The mainland assemblages are mainly burnt and highly fragmented. When comparing burnt and unburnt bone materials, results showed a marked predominance of fish specimens within the unburnt assemblages. The burnt bone materials showed a striking preponderance of marine mammals. The burning process impairs identification and quantification of fishbone. Species presence per context complemented summary data and showed that low and medium frequency species were handled more often than summary data indicate. Intra-site studies of burnt bones demonstrated the importance of detailed studies of the taphonomic history of the faunal assemblages.</p><p> At Ajvide on the island of Gotland, large amounts of well preserved unburnt faunal remains, and ca. 600 bone fishhooks have been unearthed. Replicas of fishhooks from this assemblage were subjected to strength test, osteometric, morphological, and breakage studies. Results point to an elaborated fishing technology for capturing medium sized cod. Incremental studies of cod otoliths (ear stones) from Ajvide showed that most cod were captured in fall and winter. A comparison with the contemporaneous Jettböle site on the Åland islands, showed that in general smaller cod and herring were captured there. </p><p> The ecological conditions were somewhat different during the Neolithic. The growth pattern for cod indicate a more rapid growth for young cod but with a lower asymptotic length compared to modern cod.</p>
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Neolithic Fisheries : Osteoarchaeology of Fish Remains in the Baltic Sea RegionOlson, Carina January 2008 (has links)
The variety of fish species found at the archaeological sites indicates the exploitation of local and regional ecosystems. The focus of the fisheries varies from site to site. The study is based on the analyses of faunal materials from 10 archaeological sites from Eastern Middle Sweden, Gotland, and Åland dating to approximately 3800 – 1850 B.C. The mainland assemblages are mainly burnt and highly fragmented. When comparing burnt and unburnt bone materials, results showed a marked predominance of fish specimens within the unburnt assemblages. The burnt bone materials showed a striking preponderance of marine mammals. The burning process impairs identification and quantification of fishbone. Species presence per context complemented summary data and showed that low and medium frequency species were handled more often than summary data indicate. Intra-site studies of burnt bones demonstrated the importance of detailed studies of the taphonomic history of the faunal assemblages. At Ajvide on the island of Gotland, large amounts of well preserved unburnt faunal remains, and ca. 600 bone fishhooks have been unearthed. Replicas of fishhooks from this assemblage were subjected to strength test, osteometric, morphological, and breakage studies. Results point to an elaborated fishing technology for capturing medium sized cod. Incremental studies of cod otoliths (ear stones) from Ajvide showed that most cod were captured in fall and winter. A comparison with the contemporaneous Jettböle site on the Åland islands, showed that in general smaller cod and herring were captured there. The ecological conditions were somewhat different during the Neolithic. The growth pattern for cod indicate a more rapid growth for young cod but with a lower asymptotic length compared to modern cod.
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Spatially and Temporally Resolving Concentration and Temperature Profiles within a Fresh and a Thermally-Aged Monolith CatalystShakir, Osama January 2008 (has links)
The ability to resolve reactions within a monolith spatially and temporally is key in developing reliable kinetic models, as well as in validating proposed reaction mechanisms. In this work, two techniques, IR-thermography and spatially-resolved capillary inlet mass spectrometry (SpaciMS), were used to measure temperature and gas-phase concentrations. Specifically, they were applied to monitor the axial distribution of temperature and concentration profiles during propylene oxidation over a Pt/Al2O3 monolith-supported catalyst. Also, the effect of thermally aging the catalyst on the temperature and concentration patterns observed was investigated.
During temperature programmed oxidation experiments, the data show that conversion of propylene began at the outlet, and a reaction front generated at the rear of the monolith traveled upstream, as a moving reaction zone, thereby creating a temperature wave pattern since the reaction is exothermic. The conversion was always complete downstream of this reaction zone at any point along the catalyst. When the reactor was cooled, the conversion of propylene started to drop, accompanied by a similar temperature wave pattern that traveled in the opposite direction (from upstream to downstream) and was attributed to a phenomenon known as wrong-way behavior.
Finally, thermally aging the catalyst led to a slower and more localized moving hot zone.
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Spatially and Temporally Resolving Concentration and Temperature Profiles within a Fresh and a Thermally-Aged Monolith CatalystShakir, Osama January 2008 (has links)
The ability to resolve reactions within a monolith spatially and temporally is key in developing reliable kinetic models, as well as in validating proposed reaction mechanisms. In this work, two techniques, IR-thermography and spatially-resolved capillary inlet mass spectrometry (SpaciMS), were used to measure temperature and gas-phase concentrations. Specifically, they were applied to monitor the axial distribution of temperature and concentration profiles during propylene oxidation over a Pt/Al2O3 monolith-supported catalyst. Also, the effect of thermally aging the catalyst on the temperature and concentration patterns observed was investigated.
During temperature programmed oxidation experiments, the data show that conversion of propylene began at the outlet, and a reaction front generated at the rear of the monolith traveled upstream, as a moving reaction zone, thereby creating a temperature wave pattern since the reaction is exothermic. The conversion was always complete downstream of this reaction zone at any point along the catalyst. When the reactor was cooled, the conversion of propylene started to drop, accompanied by a similar temperature wave pattern that traveled in the opposite direction (from upstream to downstream) and was attributed to a phenomenon known as wrong-way behavior.
Finally, thermally aging the catalyst led to a slower and more localized moving hot zone.
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Spatial Organization Of Service Activities In AnkaraLevent, Tolga 01 May 2007 (has links) (PDF)
In the last decades, the spatial organization of services has become a key issue in the urban planning literature. The basic reasons for this significance are the difficulties not only in understanding this complex and context-dependent organization, but also in developing planning interventions for this organization. Moreover, author believes that the existing theoretical frameworks have some inabilities in interpreting the spatial organization at the intra-metropolitan scale. Therefore, this study basically aims to redefine the spatial organization of service activities in Ankara with a relational
perspective, and consequently, to develop an information-base for new types of planning interventions. For this purpose, first, the concepts and the fields of concepts
that are integral to the spatial organization of services are examined. These concepts are the spatial patterns of concentration and dispersion and the spatial cohesiveness.
Thereafter, the analytical framework that is required to study these concepts empirically, is introduced by stating the advantages of using descriptive mathematical techniques, indicators and methodological procedures in relational perspective. In the case study, the spatial organization of services in Ankara is redefined basically with reference to the spatial patterns of concentration and dispersion and the spatial cohesiveness of services. This redefinition displays the monocentric structure of Ankara and the differentiated parts within the spatial organization of services according to the
activity compositions. Afterwards, this redefinition is utilized as the starting point for the reformulation of a new planning approach and new regulations directed towards the differentiated parts of the spatial organization of services. Finally, the methodological and contentual contributions, and also the possible further studies are presented as concluding remarks.
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Impacts of aggregated retention harvesting on the diversity patterns of nocturnal moth species assemblages in the mixedwood boreal forest of northwestern AlbertaBodeux, Brett B Unknown Date
No description available.
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Interpretando padrões espaciais de heterogeneidade funcional de ecossistemas no Rio Grande do Sul : uma abordagem mediante uso de imagens MODIS-LANDGalindo, Marcela Pinillos January 2007 (has links)
O conceito de ‘ecossistema’ emergiu da necessidade de compreender o caráter extremamente dinâmico da vegetação, interpretado a partir daí como o resultado da interação recíproca entre um dado complexo de organismos e seu conjunto amplo de fatores do ambiente físico. Um ramo das ciências ecológicas desenvolveu-se desse conceito, visando examinar o resultado de tais interações em termos de fluxos de energia, matéria e informação. Desenvolvimentos conceituais recentes apontam para uma concepção do ecossistema sob a ótica de um novo paradigma, para o qual aninhamento, hierarquia, decomposabilidade relativa, probabilidade e dependência de escala são critérios chave. Outro desenvolvimento importante, a análise de trajetórias, abriu a possibilidade de tratar a dinâmica e o funcionamento do ecossistema como fenômenos em múltiplas escalas. Incertezas metodológicas e ecológicas decorrem numa visão pouco nítida de como o funcionamento e a estrutura do ecossistema interagem sob a influência de um determinado conjunto de fatores de uso e do ambiente físico. A situação demanda uma abordagem analítica na qual classificações funcionais e estruturais sejam implementadas independentemente, com o fim de estabelecer ‘a posteriori’ quanto e como as classificações estão interconectadas. A tarefa é ainda mais desafiante, em termos de método e interpretação, quando consideramos o contexto hierárquico e complexo em que a análise deve ser feita e a dependência de definição dos resultados. Esta tese refere-se ao desenvolvimento de ferramentas conceituais e metodológicas para analisar a heterogeneidade funcional dos ecossistemas no espaço, em relação a fatores significativos de uso e do ambiente, e aos diferentes tipos de vegetação presentes numa determinada região. Com esse objetivo, adotamos o conceito de ‘Tipos Funcionais de Ecossistemas’ (TFEs), os quais reúnem unidades espaciais com padrão de funcionamento similar, sem considerar seus atributos estruturais, e avançamos num esquema classificatório de TFEs que permite capturar as respostas funcionais de curto prazo dos ecossistemas em cenários de mudanças ambientais e de uso altamente dinâmicas. Também examinamos a sensibilidade dos tipos funcionais de ecossistemas a diferentes definições de funcionamento e parâmetros de escala espacial. Os TFEs provaram ser sensíveis a estas variáveis analíticas, oferecendo assim a possibilidade de indagar a natureza multidimensional e multi-escala dos fenômenos do ecossistema. Os TFEs capturam eficientemente os aspectos mais relevantes da resposta sazonal da vegetação aos fatores do ambiente biofísico, provendo assim uma ferramenta útil para descrever a heterogeneidade espacial do funcionamento dos ecossistemas em domínios temporais e geográficos específicos. Nesta tese avançamos no reconhecimento e descrição dos principais tipos de paisagem no planalto basáltico do Rio Grande do Sul, e propomos mecanismos e controles responsáveis desses padrões característicos. Da associação espacial entre feições do terreno, solos, tipos de uso e vegetação, identificamos três tipos básicos de paisagens e definimos preliminarmente seu domínio espacial. Os resultados descrevem um forte relacionamento entre a distribuição dos grandes tipos fisionômicos de vegetação, os solos e os processos formadores de relevo. Assim sendo, os campos dominam onde relevo e solos indicam a ocorrência de remanescentes de uma antiga superfície de pediplanação, em quanto as florestas prevalecem onde os agentes geomorfológicos têm rejuvenescido a paisagem. Porém, com o objetivo de compreender os processos responsáveis destes padrões, é essencial fazer ‘downscaling’ desde a escala regional na qual os processos formadores de relevo e de solos dominam a diferenciação espacial de variáveis ecológicas, até a escala local na qual fatores biológicos e relacionados com o regime de distúrbio adquirem maior importância na produção de padrões de heterogeneidade espacial. Identificamos que a abordagem ecossistêmica funcional é a maneira mais promissora de relacionar processos de natureza tão divergente. / The ‘ecosystem’ concept emerged from the need for understanding the highly dynamic nature of the vegetation, interpreted from thereon as the reciprocal interaction among the organism-complex and a wide array of factors of the physical environment. A full branch of the ecological sciences developed from this concept, aimed to assessing the outcome of such interactions as flows of energy, matter and information. Recent conceptual developments points to a conception of ecosystem as an entity evolving under the influence of a novel paradigm, for which nestedness, hierarchy, relative decomposability, probability and scale-dependency are central. Another important development, trajectory analysis, opens the possibility to treat ecosystem dynamics and ecosystem functioning as multi-scale phenomena. Methodological and ecological uncertainties determine a rather fuzzy picture of how ecosystem function and structure interplay under the influence of some set of drivers of the physical environment and land use. The whole situation waits for an analytical path to be designed in which functional and structural classifications are carried out independently, in order to establish a posteriori whether they are connected and how they are connected. The task is even more defiant, both in terms of methods and interpretation, if we consider the already complex hierarchical context in which the analysis should be set and the definition-dependency of the outcome. This thesis is about the development of conceptual and analytical tools for analyzing the functional heterogeneity of the ecosystems in the space, in relation to meaningful environmental and land-use factors and to the different types of vegetation present over a given region. To that aim, we adopt the concept of Ecosystem Functional Types (EFTs), which enclose spatial units with similar functional patterns, no attention paid to their structure, and advance on an EFT classificatory scheme that allows capturing the short-term functional response of the ecosystems to environmental and land-use changes. Furthermore, we examine the effect of using different surrogates of ecosystem functioning on the resulting picture of functional patchiness. The effect of changing parameters of spatial scale is also tested. The Ecosystem Functional Types proved to be heavily definition-dependent and sensitive to spatial scale, which allows exploring the multi-dimensional and multi-scale nature of ecosystem phenomena. The EFTs efficiently capture the most relevant features of the seasonal response of the vegetation to the drivers of the biophysical environment, providing so a useful tool for depicting the spatial heterogeneity of ecosystem functioning in a given geographic and temporal domain. In this report we also accomplished the recognition and description of main landscape types in the basaltic tablelands of Rio Grande do Sul, and proposed mechanisms and controls responsible for their characteristic patterns. From the spatial association of terrain features, soils, land-use and vegetation, we identified three basic landscape types and broadly defined their spatial domain. The picture described tells of a rather close relationship among the distribution of the major physiognomic types of the vegetation, soils, land-use and land-forming processes. In this picture, the grasslands prevail where terrain and soil features suggest there are the remnants of an old pediplanation surface, while forests seems to dominate wherever geomorphic agents have rejuvenated the landscape. However, in order to understand the processes responsible of these patterns it is then essential to downscale from the regional realm where terrain and soil-forming phenomena dominate spatial differentiation, to the fine-scale processes at which biological and disturbance-related factors are most influential in the production of patterns of spatial heterogeneity. We identify the functional approach to the ecosystems as the most promising way to correlate processes of such a different nature.
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Padrões espaciais de localização dos empreendimentos do Programa Minha Casa Minha Vida : impactos na qualidade da habitação social e satisfação dos moradoresLima, Marcia Azevedo de January 2016 (has links)
O trabalho trata da avaliação da qualidade da produção do Programa Minha Casa Minha Vida na Região Metropolitana de Porto Alegre, na busca de subsídios para a produção da habitação social. Primeiramente, foi investigado se existem padrões espaciais de localização diferenciados para as Faixas de renda 1, 2 e 3, que poderiam gerar diferentes níveis de integração do conjunto no tecido urbano consolidado. A partir da identificação dos padrões espaciais de localização, foi verificada a existência de relação desses padrões com as diretrizes da política urbana em nível local, expressas através da regulação urbanística, propiciando localizações mais adequadas para a habitação de interesse social. Ainda, teve o objetivo de averiguar se o modelo de cidade (estrutura do espaço urbano) que está sendo produzido pelo Programa MCMV na RMPA apresentou avanços em relação à produção habitacional do BNH (Banco Nacional de Habitação), no tocante aos padrões espaciais de localização dos empreendimentos. A seguir, foram analisados se os padrões espaciais de localização geram impactos sobre as condições de mobilidade e de acesso a oportunidades de desenvolvimento humano e econômico e afetam os níveis de satisfação dos moradores com o desempenho dos conjuntos. Os procedimentos metodológicos adotados incluem múltiplos métodos de coleta de dados e análises que possibilitaram complementariedade entre os dados obtidos através de levantamento de arquivo, levantamento físico e aplicação de questionários. A análise estatística dos dados quantitativos foi realizada através da verificação das frequências e realização de testes não-paramétricos, como Kruskal-Wallis e Spearman. Foi utilizada a análise sintática para medir os níveis de integração. Os resultados obtidos confirmam que a produção do Programa Minha Casa Minha Vida apresenta um padrão espacial de localização, especialmente para a Faixa 1, com empreendimentos de médio e grande porte, distantes do centro urbano consolidado e segregados do entorno. As localizações dos empreendimentos da Faixas 2 e 3 são bastante similares, porém um pouco melhores do que as localizações dos empreendimentos da Faixa 1, que tendem promover diferentes níveis de satisfação com o desempenho dos conjuntos e diferentes impactos sobre a qualidade de vida dos moradores. Finalmente, é possível concluir que o padrão de localização dos empreendimentos do Programa MCMV na Região Metropolitana de Porto Alegre parece não apresentar avanços em relação à produção habitacional do BNH e é ressaltada a importância de avaliar os impactos da localização de conjuntos habitacionais na satisfação geral dos moradores, na busca da produção de espaços residenciais qualificados que contribuam para a sustentabilidade urbana. / The study deals with quality evaluation of the housing program “Minha Casa Minha Vida” (MCMV) implemented in the Metropolitan Region of Porto Alegre, in order to subsidize the social housing production. Firstly, it aimed at investigate if there are different patterns of spatial location according to income groups 1, 2 and 3, which might generate different levels of integration of the housing scheme in the consolidated urban grid. Secondly, it was verified whether the location patterns are related to urban legislation at local level, incorporated in the urban regulation and resulting in locations that are more appropriate to social housing production. Moreover, it was intended to explore if the structure of the urban space produced by the Program MCMV in the Metropolitan Region of Porto Alegre showed improvements in relation to social housing produced by the National Housing Bank (BNH), considering spatial patterns of location of the housing schemes. Following, the patterns of spatial location were analyzed in order to test their impacts on the conditions of mobility and access to human and economic development opportunities that affect the level of resident satisfaction with the performance of housing schemes. Methodological procedures included multiple methods of data collection and analysis which enabled complementarities between the data obtained through archive information, physical measurements and questionnaires. The statistical analysis of quantitative data was carried out by means of frequencies and non-parametric tests such as Kruskal-Wallis and Spearman correlations. Spatial syntax analysis was used in order to measure levels of integration. Results confirm the existence of patterns of location, especially for the lowest income group, with large and medium size housing schemes distant from the consolidated urban area and segregated from its surroundings. The location of housing schemes for income groups 2 and 3 are similar, but slightly better than the locations of housing schemes for income group 1, which tend to promote different levels of resident satisfaction with the performance of the housing schemes and different impacts on their quality of life. Finally, it was possible to conclude that the patterns of location of the housing schemes produced in the Program MCMV in the Metropolitan Region of Porto Alegre did not improve in relation to social housing produced by the National Housing Bank (BNH) and highlights the importance of assessing the impacts of location of housing schemes on the overall residents satisfaction, in order to produce more qualified residential spaces that promote urban sustainability.
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Interpretando padrões espaciais de heterogeneidade funcional de ecossistemas no Rio Grande do Sul : uma abordagem mediante uso de imagens MODIS-LANDGalindo, Marcela Pinillos January 2007 (has links)
O conceito de ‘ecossistema’ emergiu da necessidade de compreender o caráter extremamente dinâmico da vegetação, interpretado a partir daí como o resultado da interação recíproca entre um dado complexo de organismos e seu conjunto amplo de fatores do ambiente físico. Um ramo das ciências ecológicas desenvolveu-se desse conceito, visando examinar o resultado de tais interações em termos de fluxos de energia, matéria e informação. Desenvolvimentos conceituais recentes apontam para uma concepção do ecossistema sob a ótica de um novo paradigma, para o qual aninhamento, hierarquia, decomposabilidade relativa, probabilidade e dependência de escala são critérios chave. Outro desenvolvimento importante, a análise de trajetórias, abriu a possibilidade de tratar a dinâmica e o funcionamento do ecossistema como fenômenos em múltiplas escalas. Incertezas metodológicas e ecológicas decorrem numa visão pouco nítida de como o funcionamento e a estrutura do ecossistema interagem sob a influência de um determinado conjunto de fatores de uso e do ambiente físico. A situação demanda uma abordagem analítica na qual classificações funcionais e estruturais sejam implementadas independentemente, com o fim de estabelecer ‘a posteriori’ quanto e como as classificações estão interconectadas. A tarefa é ainda mais desafiante, em termos de método e interpretação, quando consideramos o contexto hierárquico e complexo em que a análise deve ser feita e a dependência de definição dos resultados. Esta tese refere-se ao desenvolvimento de ferramentas conceituais e metodológicas para analisar a heterogeneidade funcional dos ecossistemas no espaço, em relação a fatores significativos de uso e do ambiente, e aos diferentes tipos de vegetação presentes numa determinada região. Com esse objetivo, adotamos o conceito de ‘Tipos Funcionais de Ecossistemas’ (TFEs), os quais reúnem unidades espaciais com padrão de funcionamento similar, sem considerar seus atributos estruturais, e avançamos num esquema classificatório de TFEs que permite capturar as respostas funcionais de curto prazo dos ecossistemas em cenários de mudanças ambientais e de uso altamente dinâmicas. Também examinamos a sensibilidade dos tipos funcionais de ecossistemas a diferentes definições de funcionamento e parâmetros de escala espacial. Os TFEs provaram ser sensíveis a estas variáveis analíticas, oferecendo assim a possibilidade de indagar a natureza multidimensional e multi-escala dos fenômenos do ecossistema. Os TFEs capturam eficientemente os aspectos mais relevantes da resposta sazonal da vegetação aos fatores do ambiente biofísico, provendo assim uma ferramenta útil para descrever a heterogeneidade espacial do funcionamento dos ecossistemas em domínios temporais e geográficos específicos. Nesta tese avançamos no reconhecimento e descrição dos principais tipos de paisagem no planalto basáltico do Rio Grande do Sul, e propomos mecanismos e controles responsáveis desses padrões característicos. Da associação espacial entre feições do terreno, solos, tipos de uso e vegetação, identificamos três tipos básicos de paisagens e definimos preliminarmente seu domínio espacial. Os resultados descrevem um forte relacionamento entre a distribuição dos grandes tipos fisionômicos de vegetação, os solos e os processos formadores de relevo. Assim sendo, os campos dominam onde relevo e solos indicam a ocorrência de remanescentes de uma antiga superfície de pediplanação, em quanto as florestas prevalecem onde os agentes geomorfológicos têm rejuvenescido a paisagem. Porém, com o objetivo de compreender os processos responsáveis destes padrões, é essencial fazer ‘downscaling’ desde a escala regional na qual os processos formadores de relevo e de solos dominam a diferenciação espacial de variáveis ecológicas, até a escala local na qual fatores biológicos e relacionados com o regime de distúrbio adquirem maior importância na produção de padrões de heterogeneidade espacial. Identificamos que a abordagem ecossistêmica funcional é a maneira mais promissora de relacionar processos de natureza tão divergente. / The ‘ecosystem’ concept emerged from the need for understanding the highly dynamic nature of the vegetation, interpreted from thereon as the reciprocal interaction among the organism-complex and a wide array of factors of the physical environment. A full branch of the ecological sciences developed from this concept, aimed to assessing the outcome of such interactions as flows of energy, matter and information. Recent conceptual developments points to a conception of ecosystem as an entity evolving under the influence of a novel paradigm, for which nestedness, hierarchy, relative decomposability, probability and scale-dependency are central. Another important development, trajectory analysis, opens the possibility to treat ecosystem dynamics and ecosystem functioning as multi-scale phenomena. Methodological and ecological uncertainties determine a rather fuzzy picture of how ecosystem function and structure interplay under the influence of some set of drivers of the physical environment and land use. The whole situation waits for an analytical path to be designed in which functional and structural classifications are carried out independently, in order to establish a posteriori whether they are connected and how they are connected. The task is even more defiant, both in terms of methods and interpretation, if we consider the already complex hierarchical context in which the analysis should be set and the definition-dependency of the outcome. This thesis is about the development of conceptual and analytical tools for analyzing the functional heterogeneity of the ecosystems in the space, in relation to meaningful environmental and land-use factors and to the different types of vegetation present over a given region. To that aim, we adopt the concept of Ecosystem Functional Types (EFTs), which enclose spatial units with similar functional patterns, no attention paid to their structure, and advance on an EFT classificatory scheme that allows capturing the short-term functional response of the ecosystems to environmental and land-use changes. Furthermore, we examine the effect of using different surrogates of ecosystem functioning on the resulting picture of functional patchiness. The effect of changing parameters of spatial scale is also tested. The Ecosystem Functional Types proved to be heavily definition-dependent and sensitive to spatial scale, which allows exploring the multi-dimensional and multi-scale nature of ecosystem phenomena. The EFTs efficiently capture the most relevant features of the seasonal response of the vegetation to the drivers of the biophysical environment, providing so a useful tool for depicting the spatial heterogeneity of ecosystem functioning in a given geographic and temporal domain. In this report we also accomplished the recognition and description of main landscape types in the basaltic tablelands of Rio Grande do Sul, and proposed mechanisms and controls responsible for their characteristic patterns. From the spatial association of terrain features, soils, land-use and vegetation, we identified three basic landscape types and broadly defined their spatial domain. The picture described tells of a rather close relationship among the distribution of the major physiognomic types of the vegetation, soils, land-use and land-forming processes. In this picture, the grasslands prevail where terrain and soil features suggest there are the remnants of an old pediplanation surface, while forests seems to dominate wherever geomorphic agents have rejuvenated the landscape. However, in order to understand the processes responsible of these patterns it is then essential to downscale from the regional realm where terrain and soil-forming phenomena dominate spatial differentiation, to the fine-scale processes at which biological and disturbance-related factors are most influential in the production of patterns of spatial heterogeneity. We identify the functional approach to the ecosystems as the most promising way to correlate processes of such a different nature.
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