La dégradation de la mangrove de la Casamance a fortement été influencée par des contraintes physiques. Mais c’est l’étalement des villes du fait de la croissance démographique, les importants prélèvements de ses ressources par les populations et la mise en œuvre de techniques d’aménagements inadaptées qui ont accentué sa destruction. L’analyse de l’histoire des usages de cet écosystème, sa perception par les populations de diverses origines, les changements de législation foncière et le contexte politique propre à la région expliquent aussi cette situation. On remarque ainsi qu’au fil des années la mangrove péri-urbaine de Ziguinchor ne cesse de perdre des surfaces. Pourtant depuis les années 1990 l’amorce de la prise de conscience croissante de son importance écosystémique a conduit à la multiplication de projets de la part des organismes de développement et de protection de l’environnement pour endiguer ce phénomène. Il ressort en revanche à la suite d’enquêtes réalisées sur le terrain auprès des populations et des opérateurs du développement que ces initiatives et notamment les reboisements de la mangrove n’ont pas toujours eu les résultats escomptés, et cela en raison de leur faible acceptabilité sociale, de l’existence de grandes disparités dans l’exécution des travaux et dans la répartition des moyens de travail.Au regard de ces difficultés, des pistes de travail sont alors proposées et notamment un Système d’Information Géographique (SIG) qui permet de faire un état actualisé des changements de l’occupation du sol.Ce travail de thèse permet de mieux comprendre les changements survenus dans l’occupation du sol et notamment la mangrove avec l’évolution des pratiques des populations et de l’augmentation de leurs besoins. Il permet aussi de disposer d’une base de données sur l’évolution des unités du sol de la région péri-urbaine de Ziguinchor. / Degradation of mangroves in Casamance has been strongly influenced by physical constraints. But it is urban sprawl due to population growth, the sharp drawdown of its resources by the population and the implementation of inadequate technical facilities to which accentuated its destruction.The analysis of the history of the uses of this ecosystem, its perception by people of diverse origins, changes in land laws and the specific political context in the region explainalso this situation. It is thus noted that over the years the peri-urban mangrove Ziguinchor keeps losing surfaces. Yet since the 1990s, the beginning of the growing awareness of its importance ecosystem led to the multiplication of projects from development and environmental protection agencies to curb this phenomenon. It appears however as a result of investigations carried out on the ground with the population and operators of these development initiatives including reforestation of mangroves have not always had the desired results, and that because of their low acceptability social, the existence of large disparities in the performance of work and in the allocation of labor resources.Given these difficulties, work tracks are proposed including a Geographic Information System (GIS) which allows for an update on changes in land use.This work provides insight into the changes in land use, including mangrove populations with changing practices and increasing needs. It also helps to have a database onthe development of ground units in the area peri-urban Ziguinchor.

Esta dissertação discute as ações do poder público no tocante à localização dos conjuntos habitacionais de interesse social e sua relação com a expansão urbana e criação de espaços segregados na malha urbana da cidade de Aracaju, capital do estado de Sergipe. Para isso foi elaborado, primeiramente, um histórico das políticas públicas voltadas para habitação social no Brasil, que serviu de subsídio para compreensão dos momentos e características da política desenvolvida no âmbito local. Posteriormente foi elaborado um resgate histórico da gestão desta política em Aracaju, que foi dividido em dois momentos: o primeiro cujo principal interventor urbano e gestor das políticas habitacionais foi o Governo do Estado e o seguinte quando a Prefeitura Municipal assumiu este papel. A partir dos dados obtidos por meio de pesquisa bibliográfica, documental, de campo e entrevistas, e da elaboração de tabelas e mapas, nota-se que a escolha da localização dos conjuntos, por parte do poder público, impulsionou o crescimento urbano de Aracaju, criando novos eixos de expansão urbana horizontal, sem que houvesse um planejamento ou prévia estruturação destas áreas. A contribuição da presente pesquisa está na apresentação e sistematização das ações do poder público referentes à localização dos conjuntos habitacionais em Aracaju e sua vinculação com a expansão urbana do município, gerando espaços segregados socialmente. Além disso, possibilita uma reflexão crítica sobre a influência da localização habitacional no desenvolvimento urbano de Aracaju. / The subject to be discussed in this work is the manner how actions of public policies of location of social interest housing have inducted urban sprawl as well as have given rise to socially segregated urban spots in the city of Aracaju, the capital of Sergipe. First of all, a report progress was made of public policies concerned with social interest housing in Brazil, which has contributed to an understanding of the steps and characteristics of local public policies. Then another report progress was made of mentioned public policies in Aracaju, which was divided in two parts: the first one is related to the mentioned actions of the State Government, while the second is related to the mentioned actions of the Municipality. Based on the data obtained from bibliographies, documentary as well as from field research, interviews, and elaborated maps and statistics, it is seen how the location of chosen estates for building has inducted an urban sprawl in Aracaju due to public power, though nothing was done concerning a previous planned basic structural condition in mentioned areas. This work contributes in presenting data on actions of mentioned public policies on location of social interest housing inducting urban sprawl and socially segregated urban spots in Aracaju. Besides this, this work allows a critical analysis about the influence of public policies of location of social interest housing inducting urban sprawl in Aracaju.

Esta dissertação discute as ações do poder público no tocante à localização dos conjuntos habitacionais de interesse social e sua relação com a expansão urbana e criação de espaços segregados na malha urbana da cidade de Aracaju, capital do estado de Sergipe. Para isso foi elaborado, primeiramente, um histórico das políticas públicas voltadas para habitação social no Brasil, que serviu de subsídio para compreensão dos momentos e características da política desenvolvida no âmbito local. Posteriormente foi elaborado um resgate histórico da gestão desta política em Aracaju, que foi dividido em dois momentos: o primeiro cujo principal interventor urbano e gestor das políticas habitacionais foi o Governo do Estado e o seguinte quando a Prefeitura Municipal assumiu este papel. A partir dos dados obtidos por meio de pesquisa bibliográfica, documental, de campo e entrevistas, e da elaboração de tabelas e mapas, nota-se que a escolha da localização dos conjuntos, por parte do poder público, impulsionou o crescimento urbano de Aracaju, criando novos eixos de expansão urbana horizontal, sem que houvesse um planejamento ou prévia estruturação destas áreas. A contribuição da presente pesquisa está na apresentação e sistematização das ações do poder público referentes à localização dos conjuntos habitacionais em Aracaju e sua vinculação com a expansão urbana do município, gerando espaços segregados socialmente. Além disso, possibilita uma reflexão crítica sobre a influência da localização habitacional no desenvolvimento urbano de Aracaju. / The subject to be discussed in this work is the manner how actions of public policies of location of social interest housing have inducted urban sprawl as well as have given rise to socially segregated urban spots in the city of Aracaju, the capital of Sergipe. First of all, a report progress was made of public policies concerned with social interest housing in Brazil, which has contributed to an understanding of the steps and characteristics of local public policies. Then another report progress was made of mentioned public policies in Aracaju, which was divided in two parts: the first one is related to the mentioned actions of the State Government, while the second is related to the mentioned actions of the Municipality. Based on the data obtained from bibliographies, documentary as well as from field research, interviews, and elaborated maps and statistics, it is seen how the location of chosen estates for building has inducted an urban sprawl in Aracaju due to public power, though nothing was done concerning a previous planned basic structural condition in mentioned areas. This work contributes in presenting data on actions of mentioned public policies on location of social interest housing inducting urban sprawl and socially segregated urban spots in Aracaju. Besides this, this work allows a critical analysis about the influence of public policies of location of social interest housing inducting urban sprawl in Aracaju.

abstract: After a relative period of growth (2000-06), the U.S. economy experienced a sharp decline (2007-09) from which it is yet to recover. One of the primary factors that contributed to this decline was the sub-prime mortgage crisis, which triggered a significant increase in residential foreclosures and a slump in housing values nationwide. Most studies examining this crisis have explained the high rate of foreclosures by associating it with socio-economic characteristics of the people affected and their financial decisions with respect to home mortgages. Though these studies were successful in identifying the section of the population facing foreclosures, they were mostly silent about region-wide factors that contributed to the crisis. This resulted in the absence of studies that could identify indicators of resiliency and robustness in urban areas that are affected by economic perturbations but had different outcomes. This study addresses this shortcoming by incorporating three concepts. First, it situates the foreclosure crisis in the broader regional economy by considering the concept of regional economic resiliency. Second, it includes the concept of housing submarkets, capturing the role of housing market dynamics in contributing to market performance. Third, the notion of urban growth pattern is included in an urban sprawl index to examine whether factors related to sprawl could partly explain the variation in foreclosures. These, along with other important socio-economic and housing characteristics, are used in this study to better understand the variation in impacts of the current foreclosure crisis. This study is carried out for all urban counties in the U.S. between 2000 and 2009. The associations between foreclosure rates and different variables are established using spatial regression models. Based on these models, this dissertation argues that counties with higher degree of employment diversity, encouragement for small business enterprises, and with less dependence on housing related industries, experienced fewer foreclosures. In addition, this thesis concludes that the spatial location of foreclosed properties is a function of location of origination of sub-prime mortgages and not the spatial location of the properties per se. Also importantly, the study found that the counties with high number of dissimilar housing submarkets experienced more foreclosures. / Dissertation/Thesis / Ph.D. Environmental Design and Planning 2012

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-09-12T18:03:59Z No. of bitstreams: 1 FÁBIO LUIZ BEZERRA DE OLIVEIRA – DISSERTAÇÃO (PPGRN) 2018.pdf: 9453519 bytes, checksum: f73d944a24b1f8b13852091e0606e2d2 (MD5) / Made available in DSpace on 2018-09-12T18:03:59Z (GMT). No. of bitstreams: 1 FÁBIO LUIZ BEZERRA DE OLIVEIRA – DISSERTAÇÃO (PPGRN) 2018.pdf: 9453519 bytes, checksum: f73d944a24b1f8b13852091e0606e2d2 (MD5) Previous issue date: 2018-08-10 / A cidade é consequência de uma série de implicações sociais, econômicas, culturais, ambientais e políticas que estão associadas a processos demográficos existentes que podem gerar vulnerabilidades e riscos. Portanto, o estudo da vulnerabilidade socioambiental no contexto urbano foi fundamental para analisar os fatores relacionados à qualidade e às condições de vida nas cidades. Este trabalho de pesquisa objetivou analisar as contribuições do processo de expansão urbana para o nível de vulnerabilidade socioambiental da cidade de Solânea - PB, para isso, foi importante a utilização da metodologia que possibilitou a mensuração de vulnerabilidade socioambiental. Para esse trabalho foi utilizado o Índice Geral de Vulnerabilidade Socioambiental por Bairro – IGVSB, metodologia desenvolvida por Maior (2014), com adaptação para os setores censitários do IBGE para atender a realidade da cidade de Solânea. O método empregado constituiu de pesquisa bibliográfica agregada a uma investigação exploratória, levantamentos de dados e aplicação do IGVSSC. O IGVSSC utilizou três linguagens: a quantitativa, a cartográfica e a qualitativa. Para geração do IGVSB, produziu previamente os dois índices base da metodologia: o de Vulnerabilidade Socioeconômico por Bairros - IVSB e o de Vulnerabilidade Ambiental por Bairros – IVAB. Os resultados da pesquisa consideraram que esta relação entre a dinâmica social e sua localização na cidade influência de forma direta na capacidade de resposta da população urbana de Solânea aos eventos socioambientais danosos. A segregação socioespacial direcionou a população mais fragilizada para setores com riscos de deslizamento, erosão e alagamento como demonstrado no resultado da vulnerabilidade socioambiental da cidade de Solânea. A adaptação do IGVSB para os setores censitários do IBGE possibilita a aplicação Índíce Geral de Vulnerabilidade Socioambiental para todos os municípios brasileiros. / The city is the consequence of a series of social, economic, cultural, environmental and political implications that are associated with existing demographic processes that can generate vulnerabilities and risks. Therefore, the study of socio-environmental vulnerability in the urban context is fundamental to analyze factors related to quality and living conditions in cities. This work aims to analyze the contributions of the process of urban expansion to the level of socio - environmental vulnerability of the city of Solânea - PB, for this, it is important to use methodologies that allow the measurement of social and environmental vulnerability. For this work was used the General Index of Socioenvironmental Vulnerability by Neighborhood - IGVSB, methodology developed by Mayor (2014), with adaptation for the IBGE census sectors to meet the reality of the city of Solânea. The method employed consists of bibliographic research aggregated to an exploratory investigation, data surveys and application of the IGVSSC. The IGVSSC uses three languages: the quantitative, the cartographic and the qualitative. For IGVSB generation, it has previously produced the two basic indices of the methodology: the Socioeconomic Vulnerability by Neighborhoods - IVSB and the Environmental Vulnerability by Neighborhoods - IVAB. The results of the research considered that this relationship between the social dynamics and its location in the city, directly influence the response capacity of the urban population of Solânea to harmful socioenvironmental events. Socio-spatial segregation directed the most vulnerable population to sectors with risks of landslides, erosion and flooding as demonstrated by the socio-environmental vulnerability of the city of Solânea. The adaptation of the IGVSB to the census tracts of IBGE makes it possible to apply the General Index of Social and Environmental Vulnerability to all Brazilian municipalities.

Physical-spatial and social configuration at neighborhood level, the Raval (Barcelona), an urban evaluation according with the Compact City Model Edwin Javier Azofeifa Valverde ABSTRACT In urban areas, economic development and efforts for improving the quality of citizens' lives, instead of complementing each other and contributing to the advancement of the city, both of them generate and accentuate the processes of physical and social fragmentation in cities. This thesis describes and evaluates the physical-spatial and social configuration in the neighbourhood of Raval in Barcelona, with a particular focus on the role played in that configuration by the immigrant population. The aim is to identify how those processes in which social inequality and a lack of access to certain services and facilities manifest themselves. In order to illustrate this reality and understand the configuration of Raval, population data and information regarding services, facilities, and urban furniture were gathered. The concept of compact urban development (the compact city model) was used in order to interpret the potential weaknesses in the neighbourhood, which hinder its functionality. The main drawbacks are the predominance of population groups occupying certain spaces hindering their potential integration in the...

Conventionally geographic data produced and disseminated by the national mapping agencies are used for studying various urban issues. These data are not commonly available or accessible, but also are criticized for being expensive. However, this trend is changing along with the rise of Volunteered Geographic Information (VGI). VGI, known as user generated content, is the geographic data collected and disseminated by individuals at a voluntary basis. So far, a huge amount of geographic data has been collected due to the increasing number of contributors and volunteers. More importantly, they are free and accessible to anyone.   There are many formats of VGI such as Wikimapia, Flickr, GeoNames and OpenStreetMap (OSM). OSM is a new mapping project contributed by volunteers via a wiki-like collaboration, which is aimed to create free, editable map of the entire world. This thesis adopts OSM as the main data source to uncover the hidden patterns around the urban systems. We investigated some fundamental issues such as city rank size law and the measurement of urban sprawl. These issues were conventionally studied using Census or satellite imagery data.   We define the concept of natural cities in order to assess city size distribution. Natural cities are generated in a bottom up manner via the agglomeration of individual street nodes. This clustering process is dependent on one parameter called clustering resolution. Different clustering resolutions could derive different levels of natural cities. In this respect, they show little bias compared to city boundaries imposed by Census bureau or extracted from satellite imagery. Based on the investigation, we made two findings about rank size distributions. The first one is that all the natural cities in US follow strictly Zipf’s law regardless of the clustering resolutions, which is different from other studies only investigating a few largest cities. The second one is that Zipf’s law is not universal at the state level, e.g., Zipf’s law for natural cities within individual states does not hold valid.   This thesis continues to detect the sprawling based on natural cities. Urban sprawl devours large amount of open space each year and subsequently leads to many environmental problems. To curb urban sprawl with proper policies, a major problem is how to objectively measure it. In this thesis, a new approach is proposed to measure urban sprawl based on street nodes. This approach is based on the fact that street nodes are significantly correlated with population in cities. Specifically, it is reported that street nodes have a linear relationship with city sizes with correlation coefficient up to 0.97. This linear regression line, known as sprawl ruler, can partition all cities into the sprawling, compact and normal cities. This study verifies this approach with some US census data and US natural cities. Based on the verification, this thesis further applies it to three European countries: France, Germany and UK, and consequently categorizes all natural cities into three classes: sprawling, compact and normal. This categorization provides a new insight into the sprawling detection and sets a uniform standard for cross comparing sprawling level across an entire country. / QC 20101206

As a pattern of growth, sprawl is often criticized for its extensive negative impacts. These impacts range from economic costs to health and environmental problems. Critics of sprawl have also emphasized the negative consequences of this type of growth for social neighborhood ties. The physical environment of sprawling areas, characterized by low population density, segregation of land-uses, and lack of public spaces does not provide spaces for social interaction. On the contrary, transit-oriented and mixed-use neighborhoods might encourage interaction among residents because individuals are more likely to walk from place to place which might increase opportunities for informal contact and gather. Although there is a large body of research that study the impacts of sprawl, there is little empirical research of the impacts of sprawl on social interactions among neighbors. The purpose of this study is to contribute to the understanding of sprawl impacts and to fill this gap in the current literature by exploring the relationship between urban sprawl and neighborhood social interactions at the metropolitan level. According to my results, while neither an overall index of sprawl, nor individual indicators are observed to have a statistical significant association with different dimensions of neighbor interaction; a statistical significant association was found between the use of public spaces and the type and frequency of neighbor interaction among participants in this research. As such, the use of public parks and plazas, public libraries, and in some cases community centers is positively associated with neighborhood social interaction. These results, obtained while statistically controlling for demographic characteristics, highlight the importance of public spaces on the behavior of participants.

The widespread loss and degradation of habitat constitutes the largest threat to biodiversity in North America. While regulatory programs such as the Endangered Species Act of 1973 and wetland permitting under the Clean Water Act have addressed acute assaults on critical habitat, large areas of unprotected uplands have been lost. Urban development, particularly the advent of lower density suburban and rural sprawl, has greatly diminished the extent of contiguous patches of forest habitat and introduced a host of other undesirable effects on ecosystem function. This study sought to evaluate the extent of urban sprawl and its effects on ecological integrity in Florida using Landsat-derived land cover data collected by the Florida Fish and Wildlife Conservation Commission (FWC) circa 1987 and 2003. Chapter 1 described a novel GIS technique for correcting the systematic errors in the FWC 1987 and 2003 land cover data and converting those data to a common classification system so that they could be used in any ad hoc land cover change analysis. Comparison to ground-truth observations demonstrated a significant improvement in the accuracy of the land cover data following the Land Cover Correction Process (LCCP). Change detection between 1987 and 2003 using the correct land cover revealed trends in land cover conversion that were very different from previously published results derived from the original FWC land cover data. Conversion to urban uses in the corrected data was 47,293 ha lower, and conversion to agricultural uses was reduced by 196,773 ha, resulting in 244,067 ha less anthropogenic land conversion than had been previously estimated. Although the corrected land cover data showed that overall land conversion of natural areas was lower compared to the earlier estimate, the corrected data showed proportionally greater habitat losses for four important habitat types: Pinelands (-10.08% in the corrected land cover as compared to -5.90% in the original FWC data); upland forest (-9.46% versus 6.37%); sandhill (-13.90% versus 11.18%); and scrub (-15.52% versus -9.83%). Given the relatively small areal extent of some of these habitats, the larger percent loss estimates over the study period revealed by the corrected land cover data are cause for even greater concern by conservation planners and policymakers. Now that its utility has been demonstrated, the LCCP technique can be applied to any pair of roughly similar land cover mapping datasets provided that their original classification systems can be composed by a cross-walk into a single scheme, and that one or more ancillary data sets are available to serve in the tie-breaker role performed here by the land use data from Florida's Water Management Districts. The Soil Survey Geographic (SSURGO) and State Soil Geographic (STATSGO) soils data of the National Resource Conservation Service, the National Land Cover Dataset (NLCD) or the statewide habitat mapping of the USGS GAP Analysis Program could be adapted to provide the ancillary tie-breaker data required by the LCCP to conduct change detection between disparate land cover data sources heretofore considered too incompatible for that purpose. In Chapter 2, measures of urban sprawl, habitat loss and fragmentation in Florida were estimated using the corrected land cover data for 1987 and 2003. The Northwest and North regions of the state exhibited significantly higher indices of urban sprawl, habitat loss and habitat fragmentation via application of the Moran's I statistic. Reducing urban sprawl and habitat fragmentation spatial metrics to simple ordination variables through the use of non-metric multidimensional scaling produced new measures of urban sprawl and habitat fragmentation that correlated strongly with the original FRAGSTATS metrics, but could be more easily mapped and interpreted. Urban and Habitat ordination metrics were each spatially autocorrelated (Local Moran's I and K-means grouping analyses) but not correlated to each other using the Procrustes analysis PROTEST statistic (m2 = 0.952, p = 0.061). In contrast, individual urban sprawl metrics (CA, NP, LPI, ED, SHAPE_AM and DCAD) correlated with habitat fragmentation. NP and DCAD appeared to be particularly useful in predicting fragmentation, and county governments should take measures to reduce establishment of new urban patches to minimize NP and DCAD. Chapter 3 explored the relationship between environmental outcomes in habitat loss and fragmentation and the quality of county local government comprehensive plans. The use of NMS analysis provided a powerful technique for capturing the intrinsic variability of the Local Government Comprehensive Plan (LGCP) plan scoring systems of Brody (2003) and Pannozzo (2013) into a pair of variables each that could be used to explore associations with metrics of urban sprawl, habitat fragmentation and other county characteristics that influence urban growth and development. The geographic distribution of LGCP plan quality favored coastal counties with higher quality plans over inland counties, and there was some evidence that plans in Central and South regions of Peninsular Florida were superior to those in the North and Northwest Panhandle regions. Key factors in plan quality, specifically Coordination and Management, were strongly associated with urban sprawl or habitat fragmentation outcomes. The resources available to counties in the form of tax revenues, whether the county possessed a rural or urban economy, and the county's political makeup also appeared related to LGCP plan quality, urban sprawl or habitat fragmentation outcomes. More research will be needed to elucidate the specific causal mechanisms behind the implementation of local government planning that resulted in the observed environmental outcomes.

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