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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.
71

Fragmentos florestais urbanos e interações climáticas em diferentes escalas = estudos em Campinas, SP / Urban forest fragments and climatic interactions in different scales : studies in Campinas city, São Paulo (Brazil)

Dacanal, Cristiane 10 November 2011 (has links)
Orientador: Lucila Chebel Labaki / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-09-11T21:19:20Z (GMT). No. of bitstreams: 1 Dacanal_Cristiane_D.pdf: 11178954 bytes, checksum: 264b1339c0c91df1787d0fd078e67c29 (MD5) Previous issue date: 2011 / Resumo: O processo de urbanização é causador de grandes impactos ambientais, dentre eles a extinção da vegetação nativa. Pouco se sabe sobre o efeito de fragmentos florestais no clima local urbano, apesar de haver um consenso em relação aos benefícios da vegetação na modificação do microclima e na melhoria dos níveis de conforto térmico humano. Este estudo tem como objetivos caracterizar o microclima de fragmentos florestais, remanescentes da Floresta Estacional Semidecidual, na cidade de Campinas-SP; quantificar a magnitude e a extensão do efeito de fragmentos florestais urbanos no clima do entorno edificado; e encontrar um percentual mínimo de área de fragmento florestal em relação à área total urbanizada que seja suficiente para modificar o clima local urbano. Para tanto, foram realizados monitoramentos fixos e móveis de variáveis climáticas na microescala e na escala local urbana. Os fragmentos florestais foram caracterizados por meio da abertura do dossel florestal, da área e com base em inventários. A paisagem urbana foi descrita a partir da classificação do uso do solo, sendo possível distinguir as zonas climáticas urbanas e o padrão da fronteira. Os resultados mostram que a estabilidade térmica aumenta com a área dos fragmentos florestais. Ocorrem diferenças térmicas e de umidade do ar no perfil vertical e horizontal das florestas, que são influenciadas pelo ambiente construído. Por outro lado, foi possível constatar que o efeito das florestas sobre a o clima local urbano aumenta com o percentual de área de floresta sobre o total urbanizado (A.V. / A.U.). Sugere-se uma porcentagem mínima de 20% de A.V. / A.U. No tecido urbano, recomenda-se a distribuição homogênea de fragmentos florestais, com formato regular, em uma distância de aproximadamente o dobro da largura média dos fragmentos / Abstract: The urbanization process causes major environmental impacts, among them the native vegetation extinction. Little is known about the effects of forest fragments in an urban environment, although there is a consensus regarding the benefits of vegetation in modifying the microclimate and improving the human thermal comfort. This study aims to characterize the microclimate of the forest fragments, remnants of Semideciduous Seasonal Forest, in the city of Campinas; to quantify the magnitude and extent of the effect of urban forest fragments in the climate of the surrounding buildings; and to find a minimum percentage of forest fragmentation area in relation to the total urbanized area which is sufficient to modify the local urban climate. Thus, observations of climate variables in both micro and local scales were made. The forest fragments were characterized by measurements of forest canopy openness, area and inventories. The urban landscape was described based on land use classification, being possible to distinguish the climatic urban zones and the frontier pattern. The results show that thermal stability increases with the area of forest fragments. There were differences of thermal and air humidity in the vertical and horizontal profile of forests, which are influenced by the built environment. On the other hand, it was possible to conclude that the effect of forests on the local urban climate increases along with the percentage of forest area over the total urbanized area (A.V. / A.U.). It was suggested a minimum percentage of 20% of A.V./A.U. It was recommended a homogenous distribution of forest fragments through the city, in a distance about a double of the medium fragments width / Doutorado / Arquitetura e Construção / Doutor em Engenharia Civil
72

O urbanismo progressista e a produção do espaço urbano : limites e potencialidades das AEIS em Diadema

Lobo Júnior, Licio Gonzaga January 2014 (has links)
Orientador: Prof. Dr. Jeroen Klink / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Planejamento e Gestão do Território, 2014. / Diadema, cidade da regiao metropolitana de Sao Paulo, tem uma singular trajetoria de politica urbana nas ultimas decadas, devido principalmente a serie ininterrupta de governos de inspiracao progressista, desde 1983 ate 2012. Esta trajetoria tem relacao estreita com a construcao de uma \escola de pensamento. no urbanismo brasileiro, que convencionamos aqui chamar de \urbanismo progressista., formada pela juncao do pensamento sobre a cidade no capitalismo periferico, da pratica de governos de corte popular e das lutas sociais pela Reforma Urbana. Dentre as contribuicoes do \urbanismo progressista. destaca-se a investigacao sobre a concepcao e aplicacao de instrumentos para a garantia da efetiva vigencia da funcao social da propriedade urbana e do \direito a cidade. para todas as camadas da populacao, processos cotidianamente obstaculizados pelas praticas hegemonicas do capital imobiliario. Dentre estes instrumentos destacam-se as AEIS . Areas Especiais de Interesse Social, cuja genese e aplicacao no caso concreto de Diadema sera o objeto desta dissertacao, visando aferir seus limites e potencialidade ao longo da sua aplicacao nesta cidade, desde 1994 ate 2012. / Diadema is a city in the metropolitan region of São Paulo, which has a singular trajectory of urban policy in recent decades, mainly due to the uninterrupted series of governments with progressive inspiration, from 1983 to 2012. This trajectory is closely related to the construction of a "school of thought" in the Brazilian urbanism, what we conventionally call "progressive urbanism", created by the joint of thoughts about the city in peripheral capitalism, the practice of governments with popular bases and social struggles aiming the Urban Reform. Among the contributions of the "progressive urbanism" stands out a research on the conception and application of instruments for ensuring the effective exercise of the social function of urban property and the "right to the city" for the entire population. This process was hindered by the hegemonic practices of real estate capital. Among these instruments there are the AEIS - Special Areas of Social Interest, whose genesis and application in the case of Diadema is the object of this work to verify their limits and potential throughout their application in this city, period of 1994 to 2012.
73

Diadema, planejamento e realidade: o que muda com os planos diretores / Diadema, urban planning and reality: what changes with master plans

Wagner Membribes Bossi 18 June 2009 (has links)
Este estudo aborda os planos diretores do Município de Diadema, na Região Metropolitana de São Paulo, aprovados após a Lei Orgânica Municipal de 1990, seguindo a nova ordem constitucional estabelecida pela Constituição Federal de 1988 e pela Constituição Estadual de 1989. O objeto da pesquisa é a análise do projeto de lei de 1991 para plano diretor (não aprovado) e dos planos diretores aprovados em 1994, 1998, 2002 e 2008, enfocando os instrumentos da política urbana neles contidos, bem como seus resultados alcançados durante os 15 anos de vigência do novo quadro legal e de gestão da política urbana na cidade. Este período inclui a importante promulgação do Estatuto da Cidade, lei federal 10257/2001, que norteou os ajustes introduzidos na versão de 2002. Ao final do processo investigativo são apresentadas entrevistas que registram a visão de representantes de entidades da comunidade e do poder público municipal sobre os referidos planos, seus instrumentos e os resultados obtidos. / This study addresses the master plans of the Municipality of Diadema, in the São Paulo Metropolitan Region, Brazil, developed in response to the rulings of the Municipal Organic Law of 1990, pursuant to the new constitutional guidelines in the Brazilian Constitution of 1988 and São Paulo State Constitution of 1989. By analyzing the bill that proposed a master plan in 1991 (rejected) and examining the master plans approved in 1994, 1998, 2002, and 2008, this study sought to describe the urban policy instruments included in these approaches along with results achieved during the 15 years under the new legislation and urban policy management in the municipality. This period also marked the promulgation of the City Charter under Federal Law 10257/2001, which guided the amendments to the 2002 plan. The study includes interviews with representatives of community organizations and municipal authorities who reveal the views they hold on these urban plans, their instruments, and results achieved.
74

Projeto de lei de responsabilidade territorial urbana: a construção de um referencial normativo comum em torno do parcelamento do solo urbano e da regularização fundiária sustentável / Bill of urban territorial responsibility: the construction of a reference standard on the urban land division and sustainable land tenure regularization.

Marisa Pulice Mascarenhas 16 May 2012 (has links)
O espaço urbano no Brasil se configura como locus de desigualdades, sendo ao mesmo tempo resultado e palco das dinâmicas socioambientais e econômicas e da expressão política que assume a correlação de forças emanadas dos diversos agentes envolvidos em sua produção e reprodução. Durante o principal período de urbanização brasileiro, a expansão de nossas cidades ocorreu praticamente sem a regulação do Poder Público quanto ao parcelamento do solo, cabendo aos loteadores a definição de vetores de crescimento das cidades, numa perspectiva especulativa de retorno de investimentos a partir da provisão de infraestrutura, essa sim, feita pelo Estado. O objeto desta tese é o processo de elaboração e tramitação do Projeto de Lei 3.057/2000, chamado de projeto de Lei de Responsabilidade Territorial Urbana, que trata da revisão da lei de parcelamento do solo urbano vigente, tendo um capítulo específico sobre o que denomina de \"regularizaç~o fundi|ria urbana sustent|vel\". A tramitaç~o do PL 3.057/2000 teve início pela proposta de alteração pontual de um dos artigos da atual lei nacional de parcelamento do solo, a Lei Lehmann, com o intuito de facilitar a regularização de loteamentos de interesse social. A este projeto foram apensados outros, ampliando seu escopo e atraindo para o processo de discussão variados grupos de interesses. Ao compatibilizar num instrumento normativo único as regras de parcelamento do solo urbano e de regularização fundiária sustentável, o Projeto de Lei reúne campos distintos de intervenção no urbano. A hipótese de pesquisa é que a constituição da arena pública, constituída pelos debates e audiências públicas sobre o projeto, foi determinante para seu processo de elaboração e tramitação. / The urban area in Brazil is shaped as a locus of inequalities, while being the result and the stage of the socio-environmental and economic dynamics and the political expression that takes the correlation of forces emanating from the various agents involved in its production and reproduction. During the main period of Brazilian urbanization, the expansion of our cities took place practically without the regulation of the Government as to the division of the land, with the land holders being responsible for the definition of vectors of the growth of cities, on a speculative perspective of return on investments from the provision of infrastructure, this one indeed, promoted by the state. The object of this thesis is the drafting and processing of the bill 3057/2000 , called Bill of Urban Territorial Responsibility, which deals with the revision of the law of division of urban land in force, with a specific section on what it terms \"sustainable urban land regularization\". The processing of the bill 3057/2000 was initiated by the proposed minor amendments to the articles of the current national law of land division, the Lehmann Law, in order to facilitate the settlement of social housing developments. Others were joined to this project, expanding its scope and attracting to the discussion process various interest groups. On reconciling the rules of urban land division and sustainable land regularization in a single normative instrument, the Bill brings together different fields of intervention in urban areas. The research hypothesis is that the constitution of the public arena, comprising the debates and public hearings on the project, was crucial to its drafting and processing.
75

Potencialidades e limites da outorga onerosa do direito de construir: o caso de São José dos Campos (SP) / Potentialities and limits of the onerous granting of the right to build: the case of São José dos Campos (SP)

Soraya de Paula Rosário 23 May 2018 (has links)
O Estatuto da Cidade, lei federal N. 10.257/01, reconhecido como marco regulatório de promoção da reforma urbana, passados mais de quinze anos de sua aprovação, têm sido deveras debatido quanto à sua real eficácia, em razão da inoperância de aplicabilidade de seus instrumentos urbanísticos. Esta dissertação tem como objetivo geral demonstrar, a partir de um estudo de caso, quais são os entraves enfrentados na aplicabilidade de um instrumento, para além da condição rasa da dificuldade política. Neste sentido, a narrativa revela como transcorreram as questões técnicas que permearam a implementação do instrumento Outorga Onerosa do Direito de Construir, desencadeadas durante o processo de desenvolvimento do projeto de lei de regulação do uso do solo na cidade de São José dos Campos. A partir da leitura de documentos, disponibilizados em endereço eletrônico da prefeitura na época, ou de materiais elaborados e desenvolvidos como consequência da atividade enquanto técnica da gestão pública, foram descritas algumas etapas administrativas e legais, referente ao processo deste projeto de lei. A pesquisa descortina os interesses diversos nas condutas das relações intersetoriais dos atores representativos da sociedade e os caminhos adotados nas busca de consensos. Ao final intenciona-se evidenciar a potencialidade de o instrumento e antagonicamente suas limitações de implementação, e fundamentalmente, contribuir na reflexão para a busca de estratégias de reversão do cenário atual. / The City Statute, Federal Law N. 10.257 / 01, recognized as a regulatory framework for the promotion of urban reform, more than fifteen years after its approval, has been seriously debated as to its real effectiveness, due to the inoperability of its applicability. urban tools. This dissertation aims to demonstrate, from a case study, what are the obstacles faced in the applicability of an instrument, beyond the shallow condition of political difficulty. In this sense, the narrative reveals how the technical issues that permeated the implementation of the Onerous Right of Building instrument, triggered during the development process of the land use regulation project in the city of São José dos Campos, From the reading of documents, made available at the city\'s electronic address at the time, or materials developed and developed as a consequence of the activity as a public management technique, some administrative and legal steps were described regarding the process of this bill. The research reveals the diverse interests in the conduct of the intersectoral relations of the representative actors of society and the paths adopted in the search for consensus. In the end, it is intended to highlight the potentiality of the instrument and, in an antagonistic way, its limitations of implementation, and fundamentally, to contribute to the reflection for the search of strategies of reversion of the current scenario.
76

Potencialidades e limites da outorga onerosa do direito de construir: o caso de São José dos Campos (SP) / Potentialities and limits of the onerous granting of the right to build: the case of São José dos Campos (SP)

Rosário, Soraya de Paula 23 May 2018 (has links)
O Estatuto da Cidade, lei federal N. 10.257/01, reconhecido como marco regulatório de promoção da reforma urbana, passados mais de quinze anos de sua aprovação, têm sido deveras debatido quanto à sua real eficácia, em razão da inoperância de aplicabilidade de seus instrumentos urbanísticos. Esta dissertação tem como objetivo geral demonstrar, a partir de um estudo de caso, quais são os entraves enfrentados na aplicabilidade de um instrumento, para além da condição rasa da dificuldade política. Neste sentido, a narrativa revela como transcorreram as questões técnicas que permearam a implementação do instrumento Outorga Onerosa do Direito de Construir, desencadeadas durante o processo de desenvolvimento do projeto de lei de regulação do uso do solo na cidade de São José dos Campos. A partir da leitura de documentos, disponibilizados em endereço eletrônico da prefeitura na época, ou de materiais elaborados e desenvolvidos como consequência da atividade enquanto técnica da gestão pública, foram descritas algumas etapas administrativas e legais, referente ao processo deste projeto de lei. A pesquisa descortina os interesses diversos nas condutas das relações intersetoriais dos atores representativos da sociedade e os caminhos adotados nas busca de consensos. Ao final intenciona-se evidenciar a potencialidade de o instrumento e antagonicamente suas limitações de implementação, e fundamentalmente, contribuir na reflexão para a busca de estratégias de reversão do cenário atual. / The City Statute, Federal Law N. 10.257 / 01, recognized as a regulatory framework for the promotion of urban reform, more than fifteen years after its approval, has been seriously debated as to its real effectiveness, due to the inoperability of its applicability. urban tools. This dissertation aims to demonstrate, from a case study, what are the obstacles faced in the applicability of an instrument, beyond the shallow condition of political difficulty. In this sense, the narrative reveals how the technical issues that permeated the implementation of the Onerous Right of Building instrument, triggered during the development process of the land use regulation project in the city of São José dos Campos, From the reading of documents, made available at the city\'s electronic address at the time, or materials developed and developed as a consequence of the activity as a public management technique, some administrative and legal steps were described regarding the process of this bill. The research reveals the diverse interests in the conduct of the intersectoral relations of the representative actors of society and the paths adopted in the search for consensus. In the end, it is intended to highlight the potentiality of the instrument and, in an antagonistic way, its limitations of implementation, and fundamentally, to contribute to the reflection for the search of strategies of reversion of the current scenario.
77

Household Water Demand and Land Use Context: A Multilevel Approach

Breyer, Elizabeth Yancey 04 April 2014 (has links)
Urban water use arises from a mix of scale-dependent biophysical and socioeconomic factors. In Portland, Oregon, single-family residential water use exhibits a tightly coupled relationship with summertime weather, although this relationship varies with land use patterns across households and neighborhoods. This thesis developed a multilevel regression model to evaluate the relative importance of weather variability, parcel land use characteristics, and neighborhood geographic context in explaining single-family residential water demand patterns in the Portland metropolitan area. The model drew on a high-resolution panel dataset of weekly mean summer water use over five years (2001-2005) for a sample of 460 single-family households spanning an urban-to-suburban gradient. Water use was found to be most elastic with respect to parcel-scale building size. Building age was negatively related to water use at both the parcel and neighborhood scale. Half the variation in water use can be attributed to between-household factors. Between-neighborhood variation exerted a modest but statistically significant effect. The analysis decomposed household temperature sensitivity into four components: a fixed effect common to all households, a household-specific deviation from the fixed effect, a separate extreme heat effect, and a land use effect, where lot size exaggerated the effect of temperature on water use. Results suggested that land use planning may be an effective non-price mechanism for long-range management of peak demand, as land use decisions have water use implications. The combined effects of population growth, urbanization, and climate change expose water providers to risk of water stress. Modeling fine-grain relationships among heat, land use, and water use across scales plays a role in long-range climate change planning and adaptation.
78

Função social da propriedade na escala da metrópole: construção de uma polí­tica fundiária e atuação do Departamento de Controle da Função Social da Propriedade na cidade de São Paulo (2013-2016) / Social Function of Property at the Scale of the Metropolis: construction of a land policy and the action of the Social Function of Property Control Departament at the City of São Paulo (2013-2016).

Campos, Gustavo Soares Pires de 03 April 2019 (has links)
Entre os anos de 2013 e 2016, a cidade de São Paulo apresentou a mais intensa ação de utilização dos instrumentos de indução à função social da propriedade registrada no Brasil até o presente momento. Os mais de 1300 imóveis notificados através do Parcelamento, Utilização ou Utilização Compulsória (PEUC) superam todas as outras experiências brasileiras anteriores. Esta dissertação se propõe a fazer uma reconstrução do histórico da legislação federal e municipal que permitem a atuação do Departamento de Controle da Função Social da Propriedade na cidade de São Paulo, bem como análise quantitativa de seus resultados e uma especulação qualitativa da aplicação PEUC e de seu sucedâneo, o IPTU Progressivo no Tempo. Ainda que a partir de 2017, com a mudança de gestão municipal e da diretoria do departamento - hoje coordenação - as atividades tenham sido basicamente interrompidas, o marco que os anos compreendidos entre 2013 e 2016 representam para a política fundiária paulistana devem ser registrados e analisados tamanha sua importância no atendimento do exigido constitucionalmente no tocante ao cumprimento da função social da propriedade. / Between the years of 2013 and 2016, the city of São Paulo presented the most intense use of the instruments of induction to the social function of property registered in Brazil until the present moment. The more than 1300 properties notified through the Compulsory Subdivision, Building or Utilization of Land (CSBU) surpass all previous Brazilian experiences. This dissertation proposes itself to reconstruct the history of federal and municipal legislation that allows the Social Function of Property Control Department of the in the city of São Paulo, as well as quantitative analysis of its results and a qualitative speculation of the CSBU and the Time Progressive Urban Land Tax. Even though from 2017, with the change of municipal management and the department\'s board of director - today a coordination - the activities were basically interrupted, the landmark that the years between 2013 and 2016 represent for the São Paulo land policy must be recorded and analyzed by its importance in complying with the constitutionally required in relation to the fulfillment of the social function of property.
79

Urbanised territories as a specific component of the global carbon cycle / Urbanised territories as a specific component of the global carbon cycle

Svirejeva-Hopkins, Anastasia January 2004 (has links)
Wir betrachten folgende Teile: die zusätzlichen Kohlenstoff(C)-emissionen, welche aus der Umwandlung von natürlichem Umland durch Stadtwachstum resultieren, und die Änderung des C-Flusses durch 'urbanisierte' Ökosysteme, soweit atmosphärisches C durch diese in umliegende natürliche Ökosysteme entlang der Kette “Atmosphäre -> Vegetation -> abgestorbene organische Substanzen” gepumpt wird: d.h. C-Export; für den Zeitraum von 1980 bis 2050. Als Szenario nutzen wir Prognosen der regionalen Stadtbevölkerung, welche durch ein 'Hybridmodell' generiert werden für acht Regionen. Alle Schätzungen der C-Flüsse basieren auf zwei Modellen: das Regression Modell und das sogenannte G-Modell. Die Siedlungsfläche, welche mit dem Wachstum der Stadtbevölkerung zunimmt, wird in 'Grünflächen' (Parks, usw.), Gebäudeflächen und informell städtisch genutzte Flächen (Slums, illegale Lagerplätze, usw.) unterteilt. Es werden jährlich die regionale und globale Dynamik der C-Emissionen und des C-Exports sowie die C-Gesamtbilanz berechnet. Dabei liefern beide Modelle qualitativ ähnliche Ergebnisse, jedoch gibt es einige quantitative Unterschiede. Im ersten Modell erreicht die globale Jahresemission für die Dekade 2020-2030 resultierend aus der Landnutzungsänderung ein Maximum von 205 Mt/a. Die maximalen Beiträge zur globalen Emission werden durch China, die asiatische und die pazifische Region erbracht. Im zweiten Modell erhöht sich die jährliche globale Emission von 1.12 GtC/a für 1980 auf 1.25 GtC/a für 2005 (1Gt = 109 t). Danach beginnt eine Reduzierung. Vergleichen wir das Emissionmaximum mit der Emission durch Abholzung im Jahre 1980 (1.36 GtC/a), können wir konstatieren, daß die Urbanisierung damit in vergleichbarer Grösse zur Emission beiträgt. Bezogen auf die globale Dynamik des jährlichen C-Exports durch Urbanisierung beobachten wir ein monotones Wachstum bis zum nahezu dreifachen Wert von 24 MtC/a für 1980 auf 66 MtC/a für 2050 im ersten Modell, bzw. im zweiten Modell von 249 MtC/a für 1980 auf 505 MtC/a für 2050. Damit ist im zweiten Fall die Transportleistung der Siedlungsgebiete mit dem C-Transport durch Flüsse in die Ozeane (196 .. 537 MtC/a) vergleichbar. Bei der Abschätzung der Gesamtbilanz finden wir, daß die Urbanisierung die Bilanz in Richtung zu einer 'Senke' verschiebt. Entsprechend dem zweiten Modell beginnt sich die C-Gesamtbilanz (nach annähernder Konstanz) ab dem Jahre 2000 mit einer fast konstanten Rate zu verringern. Wenn das Maximum im Jahre 2000 bei 905MtC/a liegt, fällt dieser Wert anschliessend bis zum Jahre 2050 auf 118 MtC/a. Bei Extrapolation dieser Dynamik in die Zukunft können wir annehmen, daß am Ende des 21. Jahrhunderts die “urbane” C-Gesamtbilanz Null bzw. negative Werte erreicht. / We calculate the additional carbon emissions as a result of the conversion of natural land in a process of urbanisation; and the change of carbon flows by “urbanised” ecosystems, when the atmospheric carbon is exported to the neighboring territories, from 1980 till 2050 for the eight regions of the world. As a scenario we use combined UN and demographic model′s prognoses for regional total and urban population growth. The calculations of urban areas dynamics are based on two models: the regression model and the Gamma-model. The urbanised area is sub-divided on built-up, „green“ (parks, etc.) and informal settlements (favelas) areas. The next step is to calculate the regional and world dynamics of carbon emission and export, and the annual total carbon balance. Both models give similar results with some quantitative differences. In the first model, the world annual emissions attain a maximum of 205 MtC/year between 2020-2030. Emissions will then slowly decrease. The maximum contributions are given by China and the Asia and Pacific regions. In the second model, world annual emissions increase to 1.25 GtC in 2005, beginning to decrease afterwards. If we compare the emission maximum with the annual emission caused by deforestation, 1.36GtC per year, then we can say that the role of urbanised territories (UT) is of a comparable magnitude. Regarding the world annual export of carbon by UT, we observe its monotonous growth by three times, from 24 MtC to 66 MtC in the first model, and from 249 MtC to 505 MtC in the second one. The latter, is therefore comparable to the amount of carbon transported by rivers into the ocean (196-537 MtC). By estimating the total balance we find that urbanisation shifts the total balance towards a “sink” state. The urbanisation is inhibited in the interval 2020-2030, and by 2050 the growth of urbanised areas would almost stop. Hence, the total emission of natural carbon at that stage will stabilise at the level of the 1980s (80 MtC per year). As estimated by the second model, the total balance, being almost constant until 2000, then starts to decrease at an almost constant rate. We can say that by the end of the XXI century, the total carbon balance will be equal to zero, when the exchange flows are fully balanced, and may even be negative, when the system begins to take up carbon from the atmosphere, i.e., becomes a “sink”.
80

Multitemporal Spaceborne Polarimetric SAR Data for Urban Land Cover Mapping

Niu, Xin January 2012 (has links)
Urban land cover mapping represents one of the most important remote sensing applications in the context of rapid global urbanization. In recent years, high resolution spaceborne Polarimetric Synthetic Aperture Radar (PolSAR) has been increasingly used for urban land cover/land-use mapping, since more information could be obtained in multiple polarizations and the collection of such data is less influenced by solar illumination and weather conditions.  The overall objective of this research is to develop effective methods to extract accurate and detailed urban land cover information from spaceborne PolSAR data. Six RADARSAT-2 fine-beam polarimetric SAR and three RADARSAT-2 ultra-fine beam SAR images were used. These data were acquired from June to September 2008 over the north urban-rural fringe of the Greater Toronto Area, Canada. The major landuse/land-cover classes in this area include high-density residential areas, low-density residential areas, industrial and commercial areas, construction sites, roads, streets, parks, golf courses, forests, pasture, water and two types of agricultural crops. In this research, various polarimetric SAR parameters were evaluated for urban land cover mapping. They include the parameters from Pauli, Freeman and Cloude-Pottier decompositions, coherency matrix, intensities of each polarization and their logarithms.  Both object-based and pixel-based classification approaches were investigated. Through an object-based Support Vector Machine (SVM) and a rule-based approach, efficiencies of various PolSAR features and the multitemporal data combinations were evaluated. For the pixel-based approach, a contextual Stochastic Expectation-Maximization (SEM) algorithm was proposed. With an adaptive Markov Random Field (MRF) and a modified Multiscale Pappas Adaptive Clustering (MPAC), contextual information was explored to improve the mapping results. To take full advantages of alternative PolSAR distribution models, a rule-based model selection approach was put forward in comparison with a dictionary-based approach.  Moreover, the capability of multitemporal fine-beam PolSAR data was compared with multitemporal ultra-fine beam C-HH SAR data. Texture analysis and a rule-based approach which explores the object features and the spatial relationships were applied for further improvement. Using the proposed approaches, detailed urban land-cover classes and finer urban structures could be mapped with high accuracy in contrast to most of the previous studies which have only focused on the extraction of urban extent or the mapping of very few urban classes. It is also one of the first comparisons of various PolSAR parameters for detailed urban mapping using an object-based approach. Unlike other multitemporal studies, the significance of complementary information from both ascending and descending SAR data and the temporal relationships in the data were the focus in the multitemporal analysis. Further, the proposed novel contextual analyses could effectively improve the pixel-based classification accuracy and present homogenous results with preserved shape details avoiding over-averaging. The proposed contextual SEM algorithm, which is one of the first to combine the adaptive MRF and the modified MPAC, was able to mitigate the degenerative problem in the traditional EM algorithms with fast convergence speed when dealing with many classes. This contextual SEM outperformed the contextual SVM in certain situations with regard to both accuracy and computation time. By using such a contextual algorithm, the common PolSAR data distribution models namely Wishart, G0p, Kp and KummerU were compared for detailed urban mapping in terms of both mapping accuracy and time efficiency. In the comparisons, G0p, Kp and KummerU demonstrated better performances with higher overall accuracies than Wishart. Nevertheless, the advantages of Wishart and the other models could also be effectively integrated by the proposed rule-based adaptive model selection, while limited improvement could be observed by the dictionary-based selection, which has been applied in previous studies. The use of polarimetric SAR data for identifying various urban classes was then compared with the ultra-fine-beam C-HH SAR data. The grey level co-occurrence matrix textures generated from the ultra-fine-beam C-HH SAR data were found to be more efficient than the corresponding PolSAR textures for identifying urban areas from rural areas. An object-based and pixel-based fusion approach that uses ultra-fine-beam C-HH SAR texture data with PolSAR data was developed. In contrast to many other fusion approaches that have explored pixel-based classification results to improve object-based classifications, the proposed rule-based fusion approach using the object features and contextual information was able to extract several low backscatter classes such as roads, streets and parks with reasonable accuracy. / <p>QC 20121112</p>

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