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Environmental factors influencing the distribution of southern right whales (Eubalaena australis) on the South African coastElwen, Simon Harvey 21 November 2005 (has links)
Distributional data from 32 years of aerial surveys of southern right whales (Eubalaena australis) along the south coast of South Africa were investigated using GIS, over a variety of spatial and temporal scales to test whether their discontinuous yet predictable distribution is related to environmental characteristics. Most whales were found in areas that provided reasonable protection from open ocean swell and seasonal winds as well as having sedimentary floors with gentle slopes, despite these characteristics being less common. Correlation type analyses with whale density only showed significance at the broadest scale. Cow-calf pairs were found significantly closer to shore and in shallower water than unaccompanied whales; they also segregated longshore in nursery areas. No relationship between reproductive success and distribution was found except a higher than expected incidence of neonatal strandings in areas dominated by unaccompanied whales. Habitat choice at this time of year was concluded to be related both to energy conservation for calves and lactating females and protection of neonates. / Dissertation (MSc (Zoology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted
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Adaptação da metodologia de Fragilidade Ambiental para atividades de mineração de argila : um estudo de caso visando o planejamento territorial /Vieira, Paulo Henrique. January 2018 (has links)
Orientador: Andréia Medinilha Pancher / Banca: Cenira Maria Lupinacci / Banca: Maria Isabel Castreghini de Freitas / Banca: André Luiz Pinto / Banca: Lindon Fonseca Matias / Resumo: A partir da segunda metade do século XX, através da Conferência Ambiental de Estocolmo em 1972, as análises dos impactos ambientais decorrentes de atividades antrópicas, passaram a ter uma maior relevância nas questões acerca do meio ambiente. Fóruns e Congressos ambientais (Estocolmo 1972; Rio de Janeiro 1992, e demais anos) foram conduzidos, visando a criação de propostas para minimizar os efeitos nocivos que as ações antrópicas têm sobre o meio ambiente. Dentre as atividades antrópicas que provocam impactos ambientais, destaca-se a mineração. Tal atividade ocorre na área de estudo deste trabalho, o município de Cordeirópolis/SP, cujos impactos ambientais provenientes da mineração afetam diretamente a população local. O município de Cordeirópolis/SP, localiza-se na microrregião de Limeira, e a presença de reservas de argila foi determinante para a implantação de um Polo Cerâmico Industrial, especializado na produção de revestimentos cerâmicos. O Polo Cerâmico de Santa Gertrudes (PCSG) é o maior do Continente Americano, e inclui os município de Araras, Cordeirópolis, Iracemápolis, Limeira, Piracicaba, Rio Claro e Santa Gertrudes, sendo responsável por gerar 15 mil empregos diretos; atualmente abrange 34 industrias cerâmicas, sendo que 10 dessas localizam-se em Cordeirópolis/SP. Simultaneamente ao crescimento industrial e a mineração, se intensificaram os problemas ambientais como poluição da água, solo e ar; poluição sonora; retirada da cobertura vegetal; rebaixamento do len... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: From the second half of the twentieth century, through the Stockholm Environmental Conference in 1972, analyzes of the environmental impacts of anthropic activities have become more relevant to environmental issues. Environmental forums and congresses (Stockholm 1972, Rio de Janeiro 1992, and other years) were conducted, aiming at creating proposals to minimize the harmful effects that anthropic actions have on the environment. Among the anthropic activities that cause environmental impacts, mining stands out. This activity occurs in the study area of this work, the municipality of Cordeirópolis/SP, whose environmental impacts from mining directly affect the local population. The city of Cordeirópolis/SP, is located in the Limeira microregion, and the presence of clay reserves was determinant for the implantation of an Industrial Ceramic Pole, specialized in the production of ceramic coatings. The Santa Gertrudes Ceramic Complex (PCSG) is the largest in the Americas, and includes the municipalities of Araras, Cordeirópolis, Iracemápolis, Limeira, Piracicaba, Rio Claro and Santa Gertrudes, and is responsible for generating 15,000 direct jobs; currently covers 34 ceramic industries, 10 of which are located in Cordeirópolis/SP. Simultaneously with industrial growth and mining, environmental problems such as water, soil and air pollution have intensified; noise pollution; removal of plant cover; retraction of the water table; among others. Thus, the main objective of this work wa... (Complete abstract click electronic access below) / Doutor
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History to Data: Converting Topographic Maps into Digital Elevation ModelsPierce, Briar, Ernenwein, Eileen G. 07 April 2022 (has links)
Studying past landscapes existing before the modern era (pre-1945) carries great difficulty. Historical maps can offer insight to researchers, but the two-dimensional cartographic features on these maps remain largely inaccessible for geospatial analyses. This study investigates the idea of unlocking the data within historical maps to be utilized by Geographic Information Systems (GIS). To realize this goal, the cartographic features must be extracted and converted into digital vector (line) and raster (grid) data. For the purposes of this study, we focus on the extraction of elevation contour lines in United States Geological Survey (USGS) historical topographic maps. These lines are converted into Digital Elevation Models (DEMs), thus creating historically accurate digital landscapes. To ensure a high-quality result, the topographically derived DEMs (TOPO-DEMs) are compared to modern satellite-derived DEMs. The implications of this study can be directly applied to historical, archeological, and environmental research.
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A methodology for determining mass movement susceptibility for land-use planningCimmery, Vern Walter 01 January 1976 (has links)
Land-use planning takes into consideration geologic hazards in order to protect both life and property. One type of geologic hazard is mass movement. Mass movement is a collective term for the downslope movement of mass units of debris e.g., bedrock, soil, and subsurface material, resulting from the influence of gravity and involving transporting media such as ice, snow, water, and air. As population increases, further pressures are placed on existing land use. Many areas once considered unsuitable for development due to steep slope or other physical characteristics are now experiencing problems. These areas, due to their physical characteristics, can be susceptible to mass movement. The problem is, information related to the areal distribution of susceptibility is most often not available for input to the land-use planning process. This thesis is proposing a methodology to provide general-level mass movement susceptibility maps.
The methodology is a computer application utilizing the Harvard I. M. G. R. l. D. (IMGRID) System. IMGRID is a system using grid cells as the basic units of data storage, analysis, retrieval, and display. Basically, the methodology consists of three major components or phases: (1) providing the computer with data acceptable to the machine and computer programs (input); (2) manipulation of the data and storage of map results within the machine's memory (processing); and (3) the retrieval and display of results (output).
The processing of the data is organized around susceptibility models which generate computer maps identifying areas susceptible to mass movements. Areas susceptible to moss movements are defined as portions of the landscape characterized by a set of natural characteristics existing in a stable state which will yield a failure of the material if acted upon by an external or internal triggering event either natural or man-induced.
The methodology was applied to a small area in Southwest Washington as a demonstration of how one mechanically follows it from beginning to end. Nine mass movement models were constructed based on the Varnes’ classification system and applied to a data bank containing eleven data variables. The susceptibility mops generated were analyzed to determine the significant mapping classes using the statistical output from IMGRID.
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Development and application of a water budget model for lake level fluctuation, Goose Lake basin, Oregon-CaliforniaNebert, Douglas Daniel 01 January 1985 (has links)
A water budget model was developed to estimate year-end lake volumes of Goose Lake, Oregon-California, to determine whether an accurate reconstruction of lake volumes/levels could be made with several synthesized or partial volumetric components. Components evaluated were the lake level/volume observations, precipitation, streamflow, and evaporation during the data-rich study period, 1946 to 1975. By regressing estimated year-end volumes against actual volumes (using actual volumes as the input at the beginning of each year) a correlation coefficient of 0.97 was obtained. By letting the series' year-end volumes be substituted for the following years' antecedent volumes a systematic error was created, identical in time and degree to irrigation consumptive use in the basin. The consideration of this additional component improved the self-generating series. The interaction of the components described by the model was then fed into a reconstruction model which used regression equations relating precipitation and runoff to annual tree-ring width indices. In this manner, a long-term synthetic runoff and precipitation record was developed for the basin for the period 1422 to 1964. Trends in the model output for the recent period (1830 to present) closely parallel recorded observations of lake level/volume although the range of reconstructed volumes was not as extreme as actually occurred. Nevertheless, the "actual" versus "synthesized" lake level series (1946 to 1964) were fairly well correlated (r=0.75), being significant to the 0.99 level. The study shows that tree rings are useful in the reconstruction of hydrologic and climatologic phenomena and are especially sensitive to changes in available water supply but do not show the high interannual variation seen in both precipitation and streamflow. Additionally, the tree ring record appears to be more sensitive to drought than to dry conditions in the basin and is therefore not well suited to determining the recurrence interval of high-water conditions.
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Coastal zone landscape classification using remote sensing and model developmentSlocum, Kevin R. 01 January 2002 (has links)
Coastal zone landscape characterization and empirical model development were evaluated using multi-spectral airborne imagery. Collectively, four projects are described that address monitoring and classification issues common to the resource management community. Chapter 1 discusses opportunities for remote sensing. Chapter 2 examines spectral and spatial image resolution requirements, as well as training sample selection methods required for accurate landscape classification. Classification accuracy derived from 25nm imagery with 4m pixel sizes outperformed 70nm imagery with 1m pixel sizes. Eight natural and five cultural landscape features were tested for classification accuracy. Chapter 3 investigated the ability to characterize 1m multispectral imagery into rank-ordered categorical biomass index classes of Phragmites australis. Statistical clustering and sample membership was based upon normalized field-measurements. The red imagery channel showed highly significant correlation with field measurements (p = 0.00) and explained much of its variability (r2 = 0.79). Addition of near-infra red, green, and blue image channels in a forward stepwise regression improved the coefficient of determination (r2 = 0.98). In Chapter 4, a landscape cover map was revised by incorporating expert knowledge into a simple spatial model. Examples are provided for a barrier island environment to illustrate this post-classification methodology. A prototype selection of expert rules was sufficient to change more than 20 per cent of the originally classified landscape pixels. Chapter 5 discusses the development of an empirical model that uses vegetation community classes to estimate: (a) soil type, (b) soil compaction rate, and (c) elevation. Vegetation class proved itself a reliable surrogate for estimating these variables based upon field-based statistical measures of association and significance tests. Vegetation was highly associated with four soil types (Cramer's V = 0.98) and soil compaction rates values at depths of 30 and 46cm (Cramer's V > 0.85), and was able to accurately estimate three decimeter-level elevation zones (r2 = 0.86, p = 0.00). A preliminary model to estimate transverse dune crest heights and locations under forest canopy was presented. Lastly, Chapter 6 offers a summary and concluding statements advocating continued use of remote sensing as an application tool for resource management needs.
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Relative Risk Assessment for Cape Hatteras National SeashoreBuie, John Cary 01 January 1996 (has links)
No description available.
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Extracting Topography from Historic Topographic Maps Using GIS-Based Deep LearningPierce, Briar Z, Ernenwein, Eileen G 25 April 2023 (has links)
Historical topographic maps are valuable resources for studying past landscapes, but two-dimensional cartographic features are unsuitable for geospatial analysis. They must be extracted and converted into digital formats. This has been accomplished by researchers using sophisticated image processing and pattern recognition techniques, and more recently, artificial intelligence. While these methods are sometimes successful, they require a high level of technical expertise, limiting their accessibility. This research presents a straightforward method practitioners can use to create digital representations of historical topographic data within commercially available Geographic Information Systems (GIS) software. This study uses convolutional neural networks to extract elevation contour lines from a 1940 United States Geological Survey (USGS) topographic map in Sevier County, TN, ultimately producing a Digital Elevation Model (DEM). The topographically derived DEM (TOPO-DEM) is compared to a modern LiDAR-derived DEM to analyze its quality and utility. GIS-capable historians, archaeologists, geographers, and others can use this method in their research and land management practices.
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Slope Stability Risk Assessment in Urban Development, Eastern Tennessee HillslopeHickerson, Noah, Nandi, Arpita, Jennings, David 25 April 2023 (has links) (PDF)
Landslides are a massive problem within the Appalachians causing large amounts of damage, and even loss of life. Urban development on the hill slope further destabilizes slope and accelerates failure. The objective of this project is to examine the slope stability condition at an urban community in eastern Tennessee and assess the relative risk in the area.
The first step included a digital survey of the area by collecting all available soil, geology, elevation, watershed, slope, drainage condition, stream, and building footprint data. This data was collected from a multitude of sources including but not limited to the United States Geological Survey (USGS), Environmental Systems Research Institute (ESRI) and Tennessee State Government resources. After this a process of field verification was required to confirm the validity of acquired digital data. This field verification process included four separate trips that aimed to access the extent of damage, slope condition, bedrock geology, and soil information. The data collected from the previous digital survey and field verification trips were used to prepare a landslide hazard prediction map using Weighted Overlay method in ArcGIS Pro software. To validate the accuracy of the hazard map, an unmanned aircraft system (UAS) drone survey will be completed in April 2023. A final Slope Stability Hazard Map will be produced for the urban community and the report will be shared with the community members.
The result indicated that both the soil and geology reports were spatially inaccurate as the entirety of urban development was constructed on Sevier Shale Formation, whereas Knox Formation appears on the map. The slope and hill shade information were correct including the identification of a road that was uncompleted that undercut a steep slope. After our first survey the maps were combined and weighted in a “Weighted Overlay map” with slope, curvature, and stream data to make a map that showed likely areas of risk. The study area contains multiple areas with high slope instability risk. These areas are steep slopes as high as 51° and weathered shale with a lack of vegetation that has been undercut by a roadway that was unfinished. Other areas of high concern with clear evidence of slope sliding are present with the movement of supportive foundation beams. Signs of cracking and sliding have been spotted within the road leading to some of the housing complexes. This information will then be compared to a UAS drone survey to create a final Slope Stability Hazard Map.
The urban community can plant vegetation, divert storm water, keep the slope dry, and reduce overburden pressure on the slopes to reduce further movement. Costly engineering structures like slope anchors, soil nails, and retaining walls are possible solutions and could help to support the steep and overburdened slopes.
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Vulnerabilidade às inundações em Teresina, Piauí /Chaves, Sammya Vanessa Vieira. January 2015 (has links)
Orientador: Antônio Carlos Tavares / Banca: Roseane Corrêa Grilo / Banca: Thiago Salomão de Azevedo / Banca: Diego Correa Maia / Banca: Sandra Elisa Contri Pitton / Resumo: A falta de planejamento urbano, o aumento populacional nas áreas urbanas culminando com a ocupação de áreas inadequadas para a construção de moradias, podem ser consideradas como fatores que têm contribuído para o aumento do número de pessoas afetadas pelos chamados desastres naturais ao longo dos anos. No Brasil, inexiste uma tendência natural para fenômenos de origem tectônica, como os terremotos e vulcões, no entanto, são frequentes os registros de desastres resultantes de variabilidades climáticas e instabilidades atmosféricas, como secas, inundações e deslizamentos de terra. Dentre esses desastres, as inundações são as mais recorrentes e quando ocorrem em centros urbanos adensados, os transtornos se tornam mais graves. Em Teresina, capital do estado do Piauí, assim como em muitos municípios brasileiros, as inundações são frequentes em determinados pontos da cidade durante o período chuvoso, que vai de janeiro a maio. Diante disso, pretende-se com essa pesquisa, analisar a vulnerabilidade às inundações em Teresina, à luz das características do seu sítio urbano, das funções da cidade e seu meio ambiente, apontando as áreas com maior recorrência de episódios e o perfil da população afetada. Estudos acerca da vulnerabilidade em áreas urbanas vêm sendo, nos últimos anos, valioso instrumento utilizado por diversos estudiosos no sentido de apontar as áreas das cidades em que a população é suscetível a qualquer desastre que comprometa a sua qualidade de vida e a importância desses estudos perpassa o fato de que podem subsidiar políticas públicas que minimizem os problemas de parcelas significativas dos citadinos que estão suscetíveis aos diversos desastres. Para tanto, foram utilizados como procedimento metodológico, a construção de um referencial teórico abordando os conceitos de desastres naturais, seus tipos e ocorrências no mundo e no Brasil, bem como a aplicação de questionários... / Abstract: The lack of urban planning, the increase of the population in the urban areas culminating in the occupation of areas inadequate to build houses, can be considered as factors that have contributed to the increase in the number of people affected by the natural disasters throughout the years. In Brazil, there is no natural tendency for tectonic origin phenomenon, such as earthquakes and volcanoes, however, the records of disasters resulting from climate variability and atmospheric instability, such as droughts, floods and landslides are frequent. Among these disasters, the floods are the most recurring and when they happen in the dense urban centers, the troubles become more aggravated. In Teresina, capital of the state of Piauí, just like many other Brazilian counties, the floods are frequent in specific parts of the city during the rainy season, which goes from January to May. In view of the above, it's intended with this research, to analyze the vulnerability to floods in Teresina, by the light of the characteristics of its urban site, the functions of the city and its environment, pointing out the areas with the most recurring episodes and the profile of the affected population. Studies about the vulnerability in urban areas are becoming, in the recent years, a valuable instrument used by many scholars in order to point out the areas of the city in which the population is susceptible to any disaster that can compromise their quality of life and the importance of these studies goes through the fact that they can subsidize public policies that minimize the problems of less fortunate segments of the townspeople that are susceptible to many disasters. In order to achieve this, we used as methodological procedures the making of a theoretical referential approaching the concepts of natural disasters, their types and occurrences in the world and in Brazil, as well as the application of questionnaires in segments considered vulnerable to... / Doutor
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