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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

Estudo do meio físico e caracterização da capacidade de suporte natural da região de Pirassununga/SP /

Lima, Meire Mateus de. January 2016 (has links)
Orientador: Jairo Roberto Jiménez-Rueda / Banca: Archimedes Perez Filho / Banca: Daniel Marcos Bonotto / Resumo: Os crescentes usos e ocupação do meio e utilização dos recursos naturais têm mostrado a necessidade do desenvolvimento de estudos integrados dirigidos a uma adequação das atividades do homem com a capacidade de suporte natural do meio físico. Desta forma, este projeto objetiva, para a região de Pirassununga, localizada no centro-nordeste paulista, aplicar um procedimento metodológico que auxilie a compartimentação do meio físico, mediante o uso de geotecnologias e aspectos geodinâmicos, visando o planejamento do uso e ocupação da terra, com fins de definir a suscetibilidade natural à erosão e a capacidade de suporte natural do meio. Tais informações poderão ser utilizadas pelos produtores rurais e órgãos públicos no intuito de orientar a tomada de decisões quanto às medidas de controle para os problemas ambientais encontrados, para a recuperação de áreas impactadas, bem como orientações para o uso e ocupação sustentável da terra, reduzindo os impactos negativos. Com base nos resultados das análises de drenagem, do relevo, morfoestrutural, morfotectônica e da evolução paleoambiental (isobases confluentes) nota-se que a região apresenta uma grande densidade de drenagem, variação altimétrica e de classes de declividade, assim como um intenso fraturamento, o que gera paisagens de abatimento e soerguimento de blocos (horsts e grabens), altos e baixos estruturais deformados e altos e baixos topográficos intercalados, exigindo, deste modo, indicações de manejo específicos para cada ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The increasing use and occupation of the environment and utilization of the natural resources has presented the need for the development of integrated studies driven towards an adaptation of the activities performed by people with natural support for the physical environment. This way, this project has the objective, for a region of Pirassununga, located in the center northeast of São Paulo, to apply a methodological procedure that aids the partitioning of the physical environment, with the use of geotechnologies and geodynamic aspects, seeking the planning of the soil occupation use, to define the natural susceptibility to the erosions and the capacity of natural environment support. Such information can be utilized by farmers and public agencies in the intent orientate the decision making of the control measures for the environmental problems found, for the recovery of impacted areas, as well as in orientating for sustainable soil occupation use, reducing the negative impacts. With basis on the analysis results of drainage, relief, morphostructural, morphotectonic and the paleoenvironmental (confluent isobases), it is noticed that the region presents a great density of drainage, altimetry variation and gradient classes, as well as intense fracturing, which generates a landscape of abatement and uplift of blocks (horst and grabens), high and low structural deformation and high and low interleaved topographic, demanding, in this way, specific handling indications for each ... (Complete abstract click electronic access below) / Mestre
72

Áreas verdes em Teresina-PI : aspectos legais, ambientais e de gestão /

Carvalho, Andrea Melo de. January 2015 (has links)
Orientador: Manoel Rolando Berríos Godoy / Banca: Eliane Maria Foleto / Banca: Rafael Alves Orsi / Banca: Silvia Aparecida Guarnieri Ortigoza / Banca: Diego Correa Maia / Resumo: Em Teresina/PI existem muitas áreas verdes intituladas de parques ambientais, bosques ou hortos. A maioria de tais áreas encontra-se abandonada pelo poder público e pela população do entorno, apesar de representar importantes instrumentos de conservação ambiental e de melhoria no clima urbano. Essa realidade é consubstanciada, principalmente, pela inaplicabilidade da legislação referente a áreas verdes, tanto na própria criação da área como na sua manutenção. Em grande parte, são criadas indiscriminadamente e, sem a feitura do plano de uso para sua administração, além da ausência de incentivos para uma educação ambiental direcionada à população do entorno. Isso vem provocando a degradação dessas áreas, manifestada, principalmente, através da poluição, além da desafetação das mesmas para construção de conjuntos habitacionais. Para melhor compreensão do tema buscou-se através da história analisar a origem dessas áreas verdes. Depois foi enfocada a legislação correlata. Foram apontados meios para a criação e manutenção dessas áreas verdes através da participação tanto do poder público como da iniciativa privada, através de uma gestão participativa entre Município e coletividade, objetivando um melhor aproveitamento e administração dessas áreas, evitando, dessa forma, a degradação ambiental das mesmas. Por último, foram analisadas as áreas verdes de Teresina divididas por zona / Abstract: There are many green areas in Teresina/PI called environmental parks: forests or orchards. They are important instruments for environmental conservation and improvements in the urban climate, but most of these areas are abandoned by the government and the population surrounding it, which is caused mainly because of the inapplicability of local legislation about green areas either to the creation or maintenance of the parks. In general, they are indiscriminately created and do not have a land-use plan for their management. There are no incentives for environmental education of the surrounding population and it has led to the degradation of the environmental parks - manifested mainly through pollution and government usage of these lands for housing purposes. For better understanding of the subject, this thesis sought to analyze the origin of the environmental parks throughout history. Then it focused on related legislation. Finally, it pointed out ways of creating and maintaining the aforementioned green areas through the participation of both government and private sector or the use of participative management involving municipality and community. It aims at better utilization and administration of these areas, thus avoiding environmental degradation. Lastly, it analyzes the green areas of Teresina categorized by zones / Doutor
73

Vegetation patterns in tropical forests of the Rumpi Hills and Kimbi-Fungom National Park, Cameroon, West-Central Africa

Sainge, Nsanyi Moses January 2017 (has links)
Thesis (DTech (Environmental health))--Cape Peninsula University of Technology, 2017. / Western Cameroon is thought to hold rich biodiversity and diverse vegetation types, and contains two important forest reserves: Rumpi Hills Forest Reserve (RHFR), which is lowland to montane forest located in southwestern Cameroon and Kimbi Fungom National Park (KFNP), which is a semi-deciduous and savanna forest located in northwestern Cameroon. These forest blocks form part of the continental Cameroon Mountains. Thus far, few or limited studies have been undertaken at these two sites to characterise their floristic composition, vegetation patterns, biomass, and carbon stock. Hence, the vegetation of RHFR and KFNP were inventoried from February to November 2015 in detail with the view of describing and understanding the biodiversity and vegetation patterns vis-à-vis elevation gradient. This will enable us to answer the main research questions: How does elevation and vegetation patterns influence species composition, diversity, biomass and carbon in selected wet and dry tropical forests of the Congo Basin? Are plant species equitably distributed among life forms and elevations gradient? What are the extent of land cover changes in RHFR and the KFNP? The objectives of this study were: to characterise vegetation patterns, understand how elevation influences species distributions and diversity, and evaluate biomass and carbon stock per hectare. Furthermore, the study intended to assess the vegetation cover changes over the last few decades in RHFR and KFNP in western Cameroon. RHFR and KFNP were chosen as representative forests because limited ecological studies have been carried out on these forests, and each represented a tropical wet or dry forest, respectively. The floristic composition and vegetation patterns of the reserves were studied in 25 1-ha plots in the RHFR and 17 1-ha plots in the KFNP spread along elevation gradient and different vegetation types. In each plot, the dbh of trees and lianas of diameter at breast height ≥10 cm were measured, and dbh of shrubs <10 cm were measured in nested plots of 10 m x 10 m. Remote sensing data (Landsat images) was downloaded from the Global Land Cover Facility (GLCF) and United States Geological Survey (USGS) websites to assess forest cover changes. Forest cover changes over time were compared for both sites. Satellite images from Rumpi Hills (2000 and 2015) and Kimbi Fungom forest (1979 and 2015) were used to compare past and present vegetation (forest cover changes over time). Phytosociological parameters such as basal area, relative density, relative dominance, and relative frequency were used to described forest structure and composition. The statistical program “PAST” version 2.17 was used to calculate species diversity and richness. Allometric equations were used to evaluate above ground biomass and carbon stock.
74

Mapeamento da fragilidade potencial do alto curso da Bacia Hidrográfica Do Rio Cotegipe - PR / Mapping the potential fragility of the high course of the watershed of the river Cotegipe - PR

Grisa, Kleitson Telmo 05 May 2014 (has links)
Made available in DSpace on 2017-07-10T17:51:37Z (GMT). No. of bitstreams: 1 Kleitson_Telmo_Grisa.pdf: 5688088 bytes, checksum: fd45f9a5580eb8f87c6cc2bacb8eb1af (MD5) Previous issue date: 2014-05-05 / This research aims to develop a mapping of the potential fragility of the upper course of the river Cotegipe in the City of Francisco Beltrão in the State of Paraná. Increasingly it is necessary an integrated study of the natural environment , where the elements that are present in that region are covered, so that the results are most near reality. Thus , this study provides reliable data on the upper course of the river Cotegipe with regard to conservation of the natural environment. To perform the mapping of the potential fragility of the upper course of the river was necessary to analyze the physical boundaries of the study area, slope classes and soil types . The methodology for this research is based on the concepts of analysis of potential frailty proposed by Ross (1994). Maps hypsometric, slope , land use and soil were obtained based on Elevation Aster Gdem V2 with a resolution of 30 m , found on the website www.gdem.aster.ersdac.or.jp. The results showed a relative environmental balance in the upper course of the river area Cotegipe explained more fully by the forms of land use properly than to natural factors present in the area . The knowledge provided by research serves as a basis for planning the interference in the actions performed on the conservation and exploitation of the area that makes up the upper course of the river Cotegipe / Esta pesquisa tem como objetivo apresentar o mapeamento da fragilidade potencial do alto curso do rio Cotegipe no Município de Francisco Beltrão no Estado do Paraná. Cada vez mais se faz necessário um estudo integrado do ambiente natural, onde sejam contemplados os elementos que estão presentes naquela região, para que os resultados encontrados sejam os mais próximos à realidade. Sendo assim, esta pesquisa fornece dados confiáveis sobre o alto curso do rio Cotegipe no que diz respeito à conservação do ambiente natural. Para a realização do mapeamento da fragilidade potencial do alto curso do rio Cotegipe foi necessário analisar os limites físicos da área em estudo, classes de declividade e tipos de solos. A metodologia aplicada para essa pesquisa tem base nos conceitos da análise da fragilidade potencial, propostos por Ross (1994). Os mapas de hipsometria, declividade, solos e uso dos solos foram obtidos com base na Elevação Aster Gdem V2 com resolução de 30m, encontrada no site www.gdem.aster.ersdac.or.jp. Os resultados obtidos demonstraram um relativo equilíbrio ambiental na área do alto curso de rio Cotegipe, explicados mais devidamente pelas formas de uso do solo do que propriamente aos fatores naturais presentes na área. O conhecimento proporcionado pela pesquisa serve de embasamento para o planejamento da interferência nas ações executadas na preservação e na exploração da área que compõe o alto curso do rio Cotegipe
75

Relações entre a vulnerabilidade social e a fragilidade ambiental no litoral norte paulista = o caso dos municípios de Ilhabela, São Sebastião, Caraguatatuba e Ubatuba / Relations between the environmental fragility and social vulnerability on this coast : the case of municipalities in Ilhabela, São Sebastião, Ubatuba and Caraguatatuba

Diógenes, Kenia Nogueira, 1979 08 May 2011 (has links)
Orientador: Antonio Carlos Vitte / Dissertação (mestrado) - Universidade Estaudal de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-19T02:34:17Z (GMT). No. of bitstreams: 1 Diogenes_KeniaNogueira_M.pdf: 10110351 bytes, checksum: 03695d4de5c0175fedce6724f0b3d01d (MD5) Previous issue date: 2011 / Resumo: O objetivo deste trabalho é entender a relação entre fragilidade ambiental e vulnerabilidade social no litoral norte do Estado de São Paulo, que é composto pelos municípios Caraguatatuba, Ilhabela, São Sebastião e Ubatuba. A fragilidade ambiental entendida aqui é o resultado da relação entre as características do sítio natural, com seus limiares e potencialidades e as características de valorização do espaço, fruto da apropriação capitalista deste. O ambiente litorâneo em questão tem, dentre suas características naturais, uma complexa combinação entre grandes diferenças altimétricas (0m a 1000m), a proximidade da Serra do Mar com a praia, e altos índices pluviométricos (1700mm a 2500mm), que tornam os sítios urbanos bastante suscetíveis a eventos que podem deflagrar em situação de risco para sua população, além das pequenas enseadas que abrigam as cidades. Associada a essa questão natural temos a apropriação dos espaços naturais sob a ótica capitalista, onde os principais agentes produtores capitalistas do espaço tem na especulação imobiliária, nas atividades portuárias e de exploração do pré-sal seu principal caminho. O litoral norte paulista tem sido o destino de dois principais grupos populacionais distintos, o turista (ou veranista) e os trabalhadores para fornecer mão-de-obra às atividades crescentes nos últimos anos. Essa forte pressão populacional mediada pelas relações capitalistas de apropriação do espaço, culmina numa segregação sócio-espacial onde a população com menor poder aquisitivo (mas não somente estas) são levadas a habitar em áreas de risco ambiental. Uma população socialmente vulnerável é aquela que se encontra em situação de fragilidade ou desproteção frente as mudanças originadas em seu entorno. Se uma população se encontra em estado de resistência, ou resiliência ante algum evento ambiental provocado, ou por sua dinâmica natural, ou pela forma de apropriação do espaço, dizemos que essa população se encontra em estado de vulnerabilidade socioambiental. Essa situação de vulnerabilidade socioambiental se fez presente nos quatro municípios dessa pesquisa. As estratégias utilizadas para desenvolver essa pesquisa foram, um levantamento das características naturais e sociais, bem como das suas relações somada à discussão sobre as formas de apropriação desse ambiente litorâneo / Abstract: The objective of this study is to understand the relationship between environmental fragility and social vulnerability on the northern coast of São Paulo, which is composed of the municipalities Caraguatatuba, Ilhabela, São Sebastião and Ubatuba. The environmental fragility understood here is the result of the relationship between the characteristics of the natural site, with their thresholds and potential, and characteristics of the valorization of the space, result of capitalist appropriation of this. The coastal environment in question has, among its natural features, a complex combination between the big altimetric differences (0m to 1000m), the proximity of the Serra do Mar with beach, and high rainfall (1700mm to 2500mm) that make urban sites very susceptible to events that can trigger at risk for the population, beyond the small coves that are home to the cities. Associated with this natural question we have the appropriation of natural spaces in the capitalist perspective, where the main producers of the capitalist space have, in land speculation, in port activities and operation of the pre-salt, his main option. The northern coast of São Paulo has been the main target of two distinct populations, the tourist (or summer tourist ) and workers to provide manpower to the growing activities in recent years. This strong population pressure mediated by capitalist relations of appropriation of space, culminating in a sociospatial segregation where people with lower income (but not only these) are taken up residence in areas of environmental risk. A socially vulnerable population is one that is in a position of weakness or lack of protection against the changes originating from their surroundings. If a population is in a state of resistance or resilience against some environmental event or caused by its dynamic nature or by way of appropriation of space, we say that this population is in a state of socio-environmental vulnerability. This situation of socio-environmental vulnerability was present in all four municipalities of this research. The strategies used to develop this research was a survey of natural and social characteristics and their relationship, including discussion of the forms of appropriation of the coastal environment / Mestrado / Análise Ambiental e Dinâmica Territorial / Mestre em Geografia
76

Quantifying the Interaction of Wildlife and Roads: a Habitat and Movement Approach

Loraamm, Rebecca Whitehead 01 January 2015 (has links)
There is a growing need to address the effects of roadway presence on wildlife. Not only do roads directly impact gene dispersal from a movement perspective, but they limit movement of the individual animal from a habitat perspective by presenting an artificial barrier between one area of viable habitat and another. For this reason it is becoming increasingly important to quantify contact between humans and wildlife and to develop better methods for mitigating these types of conflicts. Studying habitat connectivity and animal mobility in the context of roads can provide actionable information on how, where, and when these encounters might occur in order to minimize the effects transportation networks have on wildlife. This study uses two different approaches for studying wildlife-road interactions: (1) quantifying habitat fragmentation caused by roads and (2) directly quantifying wildlife interaction with roadways. This was achieved through the development and extension of methods found in the fields of landscape ecology and time geography. First, this study demonstrates the utility of one newly created road-based landscape metric through a detailed case study via the creation of an original ArcGIS toolbox. Second, this study develops a new time-geographic methodology to probabilistically measure and predict where wildlife interactions are most likely to occur on road networks. Additionally, it is important to ensure these methods not only quantify effects of roads from habitat and movement perspectives but can be used to mitigate these conflicts in real world conservation settings. Each of these approaches individually leverages techniques found in the field of spatial optimization to strategically locate wildlife crossing structures. This study developed two new methodologies to quantify where, when, and how wildlife interactions with roads are most likely to occur: the first using road-based landscape metrics and the second using a probabilistic voxel-based time-geographic approach. To address habitat connectivity issues, one road-based landscape metric was validated on a real world data set and further advanced by developing a GIS-based tool for real world applications. Utilizing landuse and roadway layers in combination with user specified parameters, the script tools developed here readily calculate this road-based landscape metric for a given study area. To address wildlife mobility issues, probabilistic space-time prisms were used to quantify interaction probabilities between wildlife and roads. These prisms were generated for a given set of tracking points and overlaid with an intersecting roads layer in GIS. Summing the probabilities at prism-roadway intersections revealed a pattern in the likelihood of animal-roadway interactions. Finally, each method was expanded to capture habitat fragmentation and animal movement in the presence of roads over large spatial scales using location analysis techniques. This research also develops and implements new methods that explicitly address wildlife-road interactions and aid in siting potential wildlife crossing structures. Since this study directly addresses effects of roadway presence on wildlife, the techniques developed here offer an alternative approach versus existing methods from a habitat and wildlife movement perspective. These methods can aid planners in the conservation of wildlife whose habitat has been impacted by road development by identifying and targeting areas of high impact.
77

Paleoenvironmental Reconstruction of Florida Bay, South Florida, Using Benthic Foraminifera

Cheng, Jie 15 June 2009 (has links)
Efforts that are underway to rehabilitate the Florida Bay ecosystem to a more natural state are best guided by a comprehensive understanding of the natural versus human-induced variability that has existed within the ecosystem. Benthic foraminifera, which are well-known paleoenvironmental indicators, were identified in 203 sediment samples from six sediment cores taken from Florida Bay, and analyzed to understand the environmental variability through anthropogenically unaltered and altered periods. In this research, taxa serving as indicators of (1) seagrass abundance (which is correlated with water quality), (2) salinity, and (3) general habitat change, were studied in detail over the past 120 years, and more generally over the past ~4000 years. Historical seagrass abundance was reconstructed with the proportions of species that prefer living attached to seagrass blades over other substrates. Historical salinity trends were determined by analyzing brackish versus marine faunas, which were defined based on species’ salinity preferences. Statistical methods including cluster analysis, discriminant analysis, analysis of variance and Fisher’s α were used to analyze trends in the data. The changes in seagrass abundance and salinity over the last ~120 years are attributed to anthropogenic activities such as construction of the Flagler Railroad from the mainland to the Florida Keys, the Tamiami Trail that stretches from the east to west coast, and canals and levees in south Florida, as well as natural events such as droughts and increased rainfall from hurricanes. Longer term changes (over ~4000 years) in seagrass abundance and salinity are mostly related to sea level changes. Since seawater entered the Florida Bay area around ~4000 years ago, only one probable sea level drop occurring around ~3000 years was identified.
78

Ecological Niche Modeling and Sustainable Agroforestry: Climate Change Mitigation for Guatemalan Coffee

Bledsoe, April, Mosher, Danika, Ogden, Mitchell, Ayala, Monica, Joyner, T. Andrew Joyner, Luffman, Ingrid 12 April 2019 (has links)
Coffea arabica is a species with far-reaching impacts on the global economy. Nevertheless, climate-related challenges threaten the coffee industry at its source: its growing regions. The coffee industry is a significant economic driver in Guatemala, but farmers are increasingly reporting losses in crop yield and arable land due to climate-related challenges. Ecological niche modeling (ENM) can be employed to make predictions about the current and future suitability of regions for a species by identifying significant biotic or abiotic indicators. An ENM was used to project suitable land into the future using climate change projection models known as representative concentration pathways (RCPs), for the coffee plant and a number of other species. Due to the potential of shade trees to lessen heat stress on coffee plants, common shade trees for the region were modeled. Additionally, a fungus species responsible for detrimental coffee leaf rust was modeled. Results of these models indicated potential for substantial climate-related habitat losses for the coffee plant in the coming decades. Examination of model predictions allow for greater understanding of the climate-related variables affecting the ecology of the coffee plant, and the potential risks to the industry, in a changing climate. Additionally, ENM models for coffee rust and shade trees can help Guatemalan farmers make informed decisions about farm management.
79

A River Transformed: Historic Geomorphic Changes of the Lower Rio Grande in the Big Bend Region of Texas, Chihuahua, and Coahuila

Dean, David James 01 May 2009 (has links)
Over the last century, the construction and management of large dams and stream-flow diversions, and periodic drought have resulted in significant declines in stream flow of the lower Rio Grande in the Big Bend region. Reductions in mean annual flow and peak discharge have resulted in channel narrowing by the formation of vertically accreting inset floodplains. Narrowing has been temporarily interrupted by infrequent large dam releases greater than 1000 m3/s that have temporarily widened the channel; however, after each of these events, narrowing has resumed. Prior to 1942, floods of this magnitude occurred approximately once every 4 years and maintained a wide sandy channel. Since 1942, they have occurred 4 times. The decline in frequency of these large floods has resulted in a channel approximately 50% narrower than in the 1940s. Since the most recent channel widening floods in 1991, the channel has narrowed between 35 and 50%. In two large floodplain trenches, we observed between 2.75 and 3.5 m of vertical accretion during the same period. Additionally, nearly 90% of bare active channel bars have been converted to vegetated floodplains. Since 1991, the cross section channel area at the Johnson Ranch gage has decreased by approximately 30%. The reduction in cross section area and the invasion of non-native vegetation have resulted in higher flood stages, flooding at lower discharges, and continued vertical accretion. Channel narrowing has negatively impacted the native and endemic aquatic ecosystem through the loss of ecologically important habitats such as backwaters, side channels, and low velocity portions of the channel. Reductions in cross section area and resultant increased flood stages have also endangered historic cultural sites within the Big Bend region. Restoration efforts are currently underway within the region without a clear understanding of these historical channel changes and why they occurred. Our reconstruction of historical channel changes shows that the most significant periods of channel narrowing occurred during drought and increased stream-flow management. Management practices also appear to have enabled the invasion of non-native riparian species, which promoted sedimentation, bank stabilization, and additional channel narrowing. In order to restore historical measures of channel width, management options include non-native vegetation removal, common low magnitude dam releases that provide flood disturbance and prevent vegetation establishment, and large dam releases in excess of 1000 m3/s that create and maintain a wide channel. Vegetation management is expensive; and time consuming, and managed dam releases are politically unpopular and expensive, however, without the management of non-native riparian species and reinstatement of portions of the historical flood regime, ecological restoration will be difficult.
80

Preliminary inventory of lifeline systems and evaluation of seismic hazards in Reno and Sparks, Nevada

Priest, Barbara 01 January 1981 (has links)
The Reno-Sparks community is in a seismically hazardous area. Recent research indicates that a Richter 7.0 or greater magnitude earthquake could affect the area. Many of the emergency and essential facilities are situated in dangerous geological locations and are housed in outdated structures which could be severely damaged in the event of a major earthquake. Detailed site evaluations need to be made with respect to location of new structures and of existing building safety. The 1979 Unified Building Code seismic provisions should be adopted without exception; Nevada Revised Statute 278 .160 needs to be revised to require a seismic safety plan; Alquist-Priolo legislation should be implemented, and creation of a comprehensive civil defense plan for seismic hazards is essential.

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