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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.
31

THE INFLUENCE OF SURFACE MINING ON RUNOFF TIMING AND FLOW PATHWAYS IN ELK VALLEY, BRITISH COLUMBIA

Shatilla, Nadine J. 01 September 2014 (has links)
<p>Surface mining is a common method of accessing coal. In high-elevation environments, vegetation and soils are typically removed prior to the blasting of overburden rock thereby allowing access to mineable ore. The removed waste rock is deposited in adjacent valleys where it may bury existing streams. Previous research, predominantly in Appalachia, has focused on downstream water quality impacts with less focus on how streamflow response and flow pathways are affected by surface mining. This study reports on how surface mining affects streamflow hydrological and chemical responses at the headwater catchment scale in the Elk Valley, British Columbia. A paired catchment approach was utilized between May and October 2012, where a reference catch- ment (Dry Creek - DC) was compared to an impacted catchment (West Line Creek - WLC), whose area is 30% covered by deposited waste rock. Hydrometrically, WLC had considerably lower flows and exhibited a damped, slower response to precipitation events than DC. Dissolved ions were an order of magnitude greater in WLC, with conductivity (SpC) ranging between 400 μS/cm at high flow to 1300 μS/cm at low flow. A strong hysteretic pattern was observed between SpC and flow and with specific ions at WLC, suggesting dilution or changing flowpaths as the season progressed. In contrast, patterns of SpC and flow at DC did not exhibit hysteresis. Major ion hydrochemistry at WLC shows dilution affecting ion concentrations whereas results at DC are consistent with chemostatic behavior. Stable isotopes were more depleted at DC compared with WLC, suggesting different sources and timing of water contributing to streamflow. Future research will work towards a conceptual model of surface mining impacts on catchment scale processes in montane environments through increased understanding of residence time and flowpath distributions at a number of impacted and reference catchments.</p> / Master of Science (MSc)
32

Land-use and environmental changes in the Cerrados of South-Eastern Mato Grosso - Brazil

Grecchi, Rosana Cristina January 2011 (has links)
The human-induced changes of the Earth's land surfaces have been unprecedented, with outcomes often indicating degradation and loss of environmental quality. Mato Grosso State in Brazil, location of the study area, underwent extensive land-use and land-cover changes in recent decades with the rates, patterns and consequences poorly documented until now. In this context, the aim of the present research is to propose a multidisciplinary approach for quantifying historical land-use and environmental changes in the southeast part of this State, where the Cerrado biome (Brazilian savannas) has been intensively converted into agricultural lands. The methodology includes three parts: remote sensing change detection, land vulnerability mapping, and identification of key environmental indicators. Land-use/cover information was extracted from a temporal remote sensing dataset using an object-oriented classification approach, and the changes quantified employing a post-classification method. In addition, the study area was assessed for its vulnerabilities, focusing mainly on erosion risks, wetlands, and areas with limited or no suitability for crops. Finally, key environmental indicators were identified from the preceding steps and analyzed within the Organisation for Economic Co-operation and Development (OECD) Pressure-State-Response (PSR) framework. The results provided an improved mapping of the Cerrados natural vegetation conversion into crops and pastures, and indicate that the Cerrado vegetation was intensively converted and also became more fragmented in the time frame studied. Between 1985 and 2005 the area lost approximately 6491 km 2 of Cerrados (42 %). Modeling based on the Universal Soil Loss Equation indicated significant increase in erosion risk from 1985 to 2005 mainly related to the increase in crop areas and the crops' encroachment into more fragile lands.The identification of environmental indicators rendered complex environmental information more generally accessible by structuring it within the PSR framework.The indicators captured key information about land-use and environmental changes in the area, showing that agricultural expansion is the major human activity exerting pressure on natural resources at a landscape scale, and that the pattern of change included high rates of crop expansion and the use of fragile environments such as wetlands and sandy erodable soils.
33

Advancing Methods to Measure the Atmospheric CO2 Sink from Carbonate Rock Weathering

Salley, Devon, Mr. 01 April 2016 (has links)
With rising atmospheric CO2 concentrations, a detailed understanding of processes that impact atmospheric CO2 fluxes is required. While a sink of atmospheric carbon from the continents to the ocean from carbonate mineral weathering is, to some degree, offset by carbonate mineral precipitation in the oceans, efforts are underway to make direct measurements of these fluxes. Measurement of the continental sink has two parts: 1) measurement of the dissolved inorganic carbon (DIC) flux leaving a river basin, and 2) partitioning the inorganic carbon flux between the amount removed from the atmosphere and the portion from the bedrock. This study attempted to improve methods to measure the DIC flux using existing data to estimate the DIC flux from carbonate weathering within the limestone karst region of south central Kentucky. The DIC flux from the Barren River drainage basin upstream from Bowling Green in southern Kentucky and northern Tennessee, and the upper Green River drainage basin, upstream from Greensburg, Kentucky, was measured, each for a year, using U.S.G.S. discharge data and water-chemistry data from municipal water plants. A value of the (DIC) flux, normalized by time and area of carbonate rock, of 4.29 g km-3 day-1 was obtained for the Barren River, and 4.95 kg km-3 for the Green. These compared favorably with data obtained by Osterhoudt (2014) from two nested basins in the upper Green River with values of 5.66 kg km-3 day-1 and 5.82 kg km-3 day-1 upstream from Greensburg and Munfordville, respectively. Additional normalization of the values obtained in this study by average precipitation minus evapotranspiration over the area of carbonate rock, or water available for carbonate dissolution, resulted in values of 5.61x107 g C (km3 H20)- 1 day-1 (grams of carbon per cubic kilometer of water, per day) for the Barren, and 7.43x107g C (km3 H20)-1 day-1 for the Green River. Furthermore, a statistical relationship between the total DIC flux and time-volume of water available for dissolution has been observed, yielding an r2 value of 0.9478. This relationship indicates that the primary variables affecting DIC flux for these drainage basins are time and the volume of water available for dissolution.
34

A study of sustainability indicators: Hong Kong's ecological footprint

Yu, Sherman., 余雪雯. January 2002 (has links)
published_or_final_version / Geography / Master / Master of Philosophy
35

Dispersion of Ammonia from Concentrated Animal Feeding Operations

Wardall, Austin D 01 October 2016 (has links)
The purpose of this research is to investigate the dispersion of ammonia (NH3) from three Concentrated Animal Feeding Operations (CAFOs) in western Kentucky, as well as to investigate the Weather Research and Forecasting – Chemistry (WRF-Chem) model’s sensitivity response to initial NH3 concentrations under both wet conditions (significant precipitation) and dry conditions (no precipitation). As expected, pollutant concentrations generally were significantly higher near their points of origin and generally declined away from the sources. Contrary to expectations, ammonia tended to rise through the planetary boundary layer (PBL) regardless of atmospheric conditions. Results showed modeled NH3 pollution levels at the surface generally to be higher under wet conditions. A GIS-based analysis method was developed to investigate model sensitivity to initial NH3 concentrations. Using this method, it was found that WRF-Chem exhibits an exponential relation between initial NH3 concentration and the final amount of NH3 produced by the model.
36

Geomorphologic evolution of a rapidly deteriorating barrier island system with multiple sediment sources: Eastern Isles Dernieres, Louisiana, 1887 to 2006

Kirkland, Benjamin T 15 December 2012 (has links)
Trinity, East, and Wine Islands make up the eastern half of the Isles Dernieres barrier arc in south-central Louisiana. Formed following the abandonment of the Lafourche delta complex, subsidence and storm erosion have led to rapid deterioration of the system. Since 1887, the land area of the islands has decreased seventy-seven percent, and the gulf shoreline has retreated landward more than a kilometer. Wave ravinement on the shoreface of the islands is responsible for the most sediment loss; liberated sediment travels longshore to tidal inlets. The dominant ebb tidal currents then transport the sediment to where it is deposited in ebb tidal deltas or carried to the west, out of the system. A large lobe of sediment bypassing Cat Island Pass is entering the system from the eastern lower shoreface, which helps replace some of the sediment lost through wave ravinement to the upper shoreface.
37

The judicious use of environmental sustainability indicators in support of mine closure in South Africa

01 July 2015 (has links)
MSc. (Geography) / Please refer to full text to view abstract
38

Proposta metodológica para elaboração de um índice espacial de sustentabilidade ambiental aplicado a bacias hidrográficas /

Silva, Darllan Collins da Cunha e. January 2016 (has links)
Orientador: Roberto Wagner Lourenço / Resumo: Índices e indicadores ambientais são importantes mecanismos para a comunicação de informações resumidas sobre o estado em que se encontra uma Bacia Hidrográfica. A escolha da Bacia Hidrográfica como unidade de gestão territorial neste estudo foi baseada na Lei 9.433/97, enquanto que, a utilização de índices e indicadores se deve ao fato de sua comprovada eficiência em processos de gestão. Visto isso, elaborou-se um Índice de Sustentabilidade Ambiental de Bacias Hidrográficas (ISABH) que integrou informações sociais, econômicas e ambientais visando analisar a sustentabilidade dessas unidades de gestão territorial e servir de instrumento de comparação entre as Bacias Hidrográficas. Além disso, avaliou-se a correlação espacial entre as Sub-Bacias Hidrográficas com objetivo de identificar padrões ou agrupamentos que possam facilitar a gestão pública dessas unidades. Dentro das dimensões adotadas, os indicadores e índices foram selecionados considerando-se as bases territoriais definidas pelo recorte dos setores censitários municipais bem como pelo recorte das Sub-Bacias Hidrográficas. Nesse caso, o índice privilegiou as variáveis que pudessem gerar uma superfície de distribuição espacial dos dados ao longo da Bacia Hidrográfica. Para o estudo do ISABH escolheu-se a Bacia Hidrográfica do Rio Una, que está localizada no interior do Estado de São Paulo a aproximadamente 75km da capital do Estado de São Paulo, no município de Ibiúna. A partir dos resultados obtidos, foi possível veri... (Resumo completo, clicar acesso eletrônico abaixo) / Environmental index and indicators are important mechanisms for report summarized information about the state of Watershed. The choice of the Watershed as a territorial management unit in this study was based on Law 9,433/97, while the use of index and indicators is because its proven efficiency in management processes. Therefore, was prepared an Environmental Sustainability Index of Watershed (ISABH) that integrated social, economic and environmental information to analyze the sustainability of these territorial management units and serve as a comparison tool between the Watershed. Furthermore, we evaluated the spatial correlation between the Micro-Watersheds to identify patterns or groups that can facilitate public management of these units. Within the adopted dimensions, indicators and index were selected considering the territorial bases defined by the limits of the municipal census tracts as well as the outline of the Micro-Watersheds. In this case, the index favored the variables that could generate a spatial distribution of surface data along the Watershed. To study the ISABH was choose the Una River Watershed, which is located in the State of São Paulo, approximately 75km from the capital of São Paulo, in the city of Ibiúna. From the results, was found that the lowest values of ISABH occur on south of the watershed and are inserted in the rural city of Ibiúna/SP under the influence of agricultural activities and poor sanitation conditions. Still, these areas have high rates of illiteracy and income per capita lower of the residents. Furthermore, only 19.4% of the study area shows of ISABH values equal or above 0.60, indicating a reasonable quality, far from desirable, i.e, greater than 0.9. Regarding water quality, was verified a low concentration of dissolved oxygen in the water bodies ... (Complete abstract click electronic acess below) / Doutor
39

Avaliação da vulnerabilidade socioambiental dos distritos do município de São Paulo ao processo de escorregamento. / Social and environmental vulnerability assessment of the districts of São Paulo to the process of landsilde

Gamba, Carolina 16 June 2011 (has links)
Diante de tantas crises e catástrofes ocorridas nos últimos anos, relacionadas a eventos extremos de precipitação, que muitas vezes resultam em graves prejuízos materiais e, sobretudo, em perda de vidas humanas; a discussão sobre os riscos socioambientais ganha outra dimensão. O atual modelo de desenvolvimento caracteriza-se pela banalização do risco, haja vista que a produção incessante de riquezas atrela-se à produção de um número cada vez maior de contextos vulneráveis, sobretudo em áreas de grande pobreza - onde a capacidade de resposta aos diferentes impactos é bastante reduzida. No ambiente urbano, o problema é ainda mais evidenciado, pela grande extensão das áreas ocupadas por assentamentos precários. As mudanças microclimáticas observadas nas grandes metrópoles, bem como os cenários apresentados pelo Painel Intergovernamental de Mudança do Clima, apontam a necessidade do desenvolvimento de medidas que visem ao gerenciamento adequado de riscos relacionados a eventos extremos, uma vez que estes podem se tornar mais frequentes e intensos nas próximas décadas. Este trabalho procura realizar uma análise multidimensional da vulnerabilidade do município de São Paulo frente a processos relacionados a chuvas intensas, em especial os escorregamentos de vertentes. Pretende apontar no espaço paulistano a estreita relação entre vulnerabilidade social e infraestrutural; e as áreas mais suscetíveis a este tipo de fenômeno, situação que caracteriza a segregação urbana. Para tal, faz-se uso de indicadores socioambientais. Com base em dados secundários, obtidos junto ao IBGE e à Prefeitura do Município de São Paulo, desenvolveu-se um conjunto de índices sintéticos. Os mesmos foram integrados e inseridos num Sistema de Informação Geográfica, com vistas a apontar diferentes níveis de vulnerabilidade socioambiental entre os distritos frente ao processo de escorregamento. / With so many crises and disasters in recent years, related to extreme precipitation events, which often result in serious damage and, especially, loss of human lives, the discussion on social and environmental risks gains another dimension. The current model of development is characterized by the risk trivialization, considering that the incessant production of wealth is linked to the production of an increasing number of vulnerable contexts, especially in areas of great poverty - where the response to different impacts is greatly reduced. In the urban environment, the problem is further evidenced by the large extent of areas occupied by slums. The microclimatic changes observed in the large cities, as well as the scenarios presented by the Intergovernmental Panel on Climate Change, indicate the need for developing measures for the proper management of risks related to extreme events, since these may become more frequent and intense in the coming decades. This study seeks to accomplish a multi-dimensional analysis of the vulnerability of São Paulo city against processes related to heavy rainfall, particularly the landslides. Intends to point in space paulistano the close relationship between social and infrastructural vulnerability, and the areas most susceptible to this type of phenomenon, a situation that characterizes urban segregation. To do this, makes use of social and environmental indicators. Based on secondary data, obtained from the IBGE and the Municipality of Sao Paulo, was developed a set of synthetic indices. They were integrated and included in a Geographic Information System, in order to point out different levels of socio-environmental vulnerability among districts facing the process of landslide.
40

Morbidade por problemas respiratórios em Ribeirão Preto-SP, de 1995 a 2001, segundo indicadores ambientais, sociais e econômicos. / Morbidity by respiratory problems in Ribeirão Preto-SP, from 1995 to 2001, according to environmental, social and economics indicators.

Roseiro, Maria Nazareth Vianna 17 December 2002 (has links)
Os problemas respiratórios representaram a segunda causa de morbidade na distribuição de doenças no país, no ano 2000 (MS, 2002), tendo como uma das principais causas a poluição atmosférica, dentre outros fatores. Os efeitos na saúde devido à poluição do ar têm sido tema intensamente estudado nos últimos anos, mostrando que a exposição a poluentes atmosféricos vem causando um aumento na morbi-mortalidade e nas internações hospitalares devido a problemas respiratórios (Brunekreef & Holgate, 2002). Em Ribeirão Preto, cidade do estado de São Paulo, considerada o maior pólo sucro-alcooleiro do mundo, a prática da queima da palha da cana-de-açúcar vem causando grande discussão pelo incômodo aos moradores e pelos danos à saúde. A colheita da cana-de-açúcar ocorre no inverno, entre os meses de maio e novembro. Esta pesquisa teve o objetivo de descrever o quadro de morbidade ligado às internações hospitalares por problemas respiratórios nesse município, no período de 1995 a 2001, baseando-se em indicadores ambientais, econômicos e sociais. A metodologia fundamenta-se na pesquisa epidemiológica não-experimental, descritivo-exploratória, caracterizando-se em um estudo retrospectivo. As variáveis independentes consideradas foram o Índice de Poluição Atmosférica em Ribeirão Preto, medido pela CETESB, os indicadores econômicos como PIB e renda per capita, fornecidos pela Prefeitura Municipal e Associação Comercial e Industrial de Ribeirão Preto e os indicadores sociais, IDH, IDH-M e ICV do município. As internações hospitalares na rede pública do município por problemas respiratórios constituíram a variável dependente. Os sujeitos da pesquisa foram formados por toda a população residente no município de Ribeirão Preto no período do estudo, independente de sexo, cor, profissão, faixa etária e nível sócio-cultural, internada nos hospitais da rede pública em decorrência de distúrbios respiratórios. Dentre os resultados destaca-se que o grupo que mais necessitou de hospitalização na rede pública foi o constituído por crianças de até 4 anos, principalmente menores de um ano de idade, seguido por idosos acima de 50 anos, em especial do grupo feminino, embora os homens tenham utilizado mais a rede pública hospitalar para a internação hospitalar do que as mulheres. Os poluentes atmosféricos medidos no município, nesses anos estudados, foram o SO2 e a Fumaça, sendo que as concentrações de SO2 apresentaram-se abaixo dos limites preconizados para padrão primário pela OMS, USEPA e CETESB e as taxas de concentração de Fumaça, com exceção das referentes ao ano 2000, encontraram-se acima dos valores aceitos pelos mesmos órgãos no que refere a padrão secundário. Os indicadores econômicos e sociais demonstraram um alto nível de desenvolvimento, em escala crescente nos anos selecionados. Os dados mostraram que há uma estreita relação entre o nível de desenvolvimento econômico e social em Ribeirão Preto-SP, no período de 1995 e 2001 e o quadro epidemiológico retratado pelas internações hospitalares por problemas respiratórios. / The breathing problems represented the second reason of morbidity in the sickness distribution in the country, in 2000, having as principal cause the atmospheric pollution, among another factors. The effects of air pollution on health has been broadly studied the last years, showing an increment in the morbidity and mortality associated with breathing problems. In Ribeirao Preto, city of Sao Paulo State, considered the most important productor center of sugar cane, the burning practice is been discussing because of the troubles the generate to the population and the health damage. Sugar cane colletion is done in winter, from may to november. This research aim the describe the morbidity associated with the hospital admissions for respiratory causes in this city from 1995 to 2001, based on environmental, economics and social indicators. It was done an epidemiological research, non experimental, descriptive and explorative, characterized by a retrospective study. As independent parameters were used the Atmospheric Pollution Indicator (CETESB), economic indicators such as PIB and income per capita (from the Ribeirao Preto City Office and the Comercial and Industrial Association of Ribeirao Preto) and the social indicators were the HDI, HDI-M and VCI from the Ribeirao Preto City Office. As dependend parameter was sellected the hospital admissions for respiratory causes. Any person hospitalized in the municipal system with respiratory problems, living in Ribeirao Preto, was included in this research, were not considered sex, color, profession, age or social and cultural level. Among the results it can be observed that the group that needed hospital admissions more frequently was constituded by childrens up to 4 years old, especially during the first year of life. This group was followed by adults over 50 years old, especially the female, altough men had used also the municipal system for treatment. The atmospheric contaminants analyzed in Ribeirao Preto, were SO2 and smog. The levels of SO2 were bellow the primary standard level established by OMS, USEPA and CETESB. The smog levels, excepting the data from 2000, were over the established as secondary standards levels. The economic asn social indicators are showing a high level of development in Ribeirao Preto-SP, been incremented from 1995 to 2001. Data showed that exist an important relation between the economic and social indicators, in that time, and the breathing problems hospitalization rates.

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