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Surface impacts of gold mining activities on the Kromdraai/Koekemoerspruit : a situation analysis / Alida Jane BothaBotha, Alida Jane January 2015 (has links)
Six point sources of potential contamination from gold mine tailings were identified along the Kromdraai/Koekemoerspruit drainage basin. The degree of contamination of the tailings, soils, surface water, stream sediments and plants at each point source, as well as the individual contribution of these point sources to the contamination of downstream localities was determined by means of quantitative indices. These indices include availability percentage, threshold exceedance ratio, geoaccumulation index, bioaccumulation index and hyperaccumation threshold exceedance ratio. Both the total concentration pool as well as the available (soluble) fraction thereof were evaluated relative to pH and plant uptake, and as applicable to the sample type, by using the USEPA 3050b and DIN 19730 (NH4NO3) extraction methods, respectively. The results for the eight selected potentially toxic trace elements (Cr, Co, Ni, Cu, Pb, Zn, As and U) were further categorised under current and potential future contamination statuses and discussed according to a source-pathway-receptor model relative to individual localities. Composite sampling was employed to provide a representative average of each locality for an overall contamination profile of the study area. Plant species were classified according to accumulation degree and hyperaccumulation status in order to derive an indication of accumulation efficiency relative to the geochemical status of soils or tailings. A document was compiled in order to be used as a guideline for rehabilitation purposes specific to a geochemically-contaminated drainage system. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
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Surface impacts of gold mining activities on the Kromdraai/Koekemoerspruit : a situation analysis / Alida Jane BothaBotha, Alida Jane January 2015 (has links)
Six point sources of potential contamination from gold mine tailings were identified along the Kromdraai/Koekemoerspruit drainage basin. The degree of contamination of the tailings, soils, surface water, stream sediments and plants at each point source, as well as the individual contribution of these point sources to the contamination of downstream localities was determined by means of quantitative indices. These indices include availability percentage, threshold exceedance ratio, geoaccumulation index, bioaccumulation index and hyperaccumation threshold exceedance ratio. Both the total concentration pool as well as the available (soluble) fraction thereof were evaluated relative to pH and plant uptake, and as applicable to the sample type, by using the USEPA 3050b and DIN 19730 (NH4NO3) extraction methods, respectively. The results for the eight selected potentially toxic trace elements (Cr, Co, Ni, Cu, Pb, Zn, As and U) were further categorised under current and potential future contamination statuses and discussed according to a source-pathway-receptor model relative to individual localities. Composite sampling was employed to provide a representative average of each locality for an overall contamination profile of the study area. Plant species were classified according to accumulation degree and hyperaccumulation status in order to derive an indication of accumulation efficiency relative to the geochemical status of soils or tailings. A document was compiled in order to be used as a guideline for rehabilitation purposes specific to a geochemically-contaminated drainage system. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
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Mapeamento e avaliação da vegetação urbana da cidade de Vitória-ES, utilizando geotecnologias / Mapping and assessment of the urban vegetation of the town of Vitoria-ES, using geotechnologySouza, Samira Murelli de 15 July 2011 (has links)
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Previous issue date: 2011-07-15 / Taking the set of intra-urban vegetation as a factor to be considered in the environmental quality of a city, this study aims analyzing qualitative and quantitatively the vegetation of the city of Vitoria-ES. Initially was obtained the mapping of 17 classes of vegetation, from image interpretation techniques and scanning, on a scale of 1:1,500 using the computer application ArcGIS 10, which allowed the analysis of the distribution of classes by the urban mesh, as well as calculations of percentages and indexes of vegetation coverage, open spaces and green areas, per inhabitant. Were found 46,504 vegetation areas, equivalent to a total of 1393.38 ha, representing 14.98% of the study area. For all indexes were found very low values when correlated to indexes proposed by other authors and recommended by the Urban Afforestation Brazilian Society (15 m²/inhabitant), pointing out that the configuration of the vegetation is poorly distributed, favoring the regions finest, while there is a shortage in the neighborhoods more peripherals. Next, were analyzed the benefits of the vegetation using the relation between vegetation and the behavior of varying temperature and relative humidity throughout the day, at three sites with different environmental conditions, being they the Moscoso Park (Center), the Square Philogomiro Lannes (Jardim da Penha) and a forest fragment on the campus of UFES (Goiabeiras). The results of this analysis showed that, in the most wooded location, with less spaces built and paved, there is a strong influence on the alleviation of the air temperature and increase of the humidity. Finally, was prepared a spatialization map of annual average temperature the air of Vitoria, obtained by means of Digital Elevation Model (DEM) SRTM (Shuttle Radar Topography Mission) and equation Multiple regression adjusted. It was proven from the map that the Massif Central, place of higher altitude and greater forest fragment that comprises the city of Vitoria, shows up to 2 ° C below the annual average temperature across the city, estimated between 24.5 to 25 °C / Tomando-se o conjunto da vegetação intraurbana como um dos fatores a ser considerado na qualidade ambiental de uma cidade, este trabalho tem por finalidade, analisar qualitativa e quantitativamente a vegetação da cidade de Vitória-ES. Inicialmente foi obtido o mapeamento de 17 classes de vegetação, a partir de técnicas de fotointerpretação e digitalização, na escala de 1:1.500, utilizando o aplicativo computacional ArcGIS 10, o que possibilitou a análise da distribuição das classes pela malha urbana, bem como os cálculos das porcentagens e índices de cobertura vegetal, espaços livres e áreas verdes, por habitante. Foram encontradas 46.504 áreas de vegetação, equivalente a um total de 1.393,38 ha, representando 14,98% da área de estudo. Para todos os índices foram constatados valores bastante baixos quando correlacionados a índices propostos por outros autores e ao recomendado pela Sociedade Brasileira de Arborização Urbana (15 m²/habitante), mostrando ainda que a configuração da vegetação é mal distribuída, favorecendo as regiões mais nobres, enquanto há carência nos bairros mais periféricos. Em seguida, foram analisados os benefícios da vegetação, por meio da relação entre a vegetação e o comportamento das variáveis temperatura e umidade relativa do ar, ao longo do dia, em três locais com diferentes condições ambientais, sendo eles o Parque Moscoso (Centro), a Praça Philogomiro Lannes (Jardim da Penha) e um fragmento florestal no campus da UFES (Goiabeiras). Os resultados desta análise comprovaram que, nos locais mais arborizados, com menos espaços construídos e pavimentados, há forte influência na amenização da temperatura do ar e no aumento da umidade. Por último, foi elaborado o mapa de espacialização da temperatura média anual do ar de Vitória, obtido por meio de modelo digital de elevação (MDE) SRTM (Shuttle Radar Topography Mission) e equação de regressão múltipla ajustada. Ficou comprovado, a partir do mapa, que o Maciço Central, local de maior altitude e maior fragmento florestal urbano que compõe a cidade de Vitória, apresenta até 2º C abaixo da temperatura média anual de toda a cidade, estimada entre 24,5 a 25° C
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