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Green, Stewart Christopher. "The regulation of sand mining in South Africa." Master's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/4475.
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Sand, an important input to the construction industry, is extensively mined from the environment leading to depletion of the resource as well as damage to riparian habitat and the alteration of river beds and banks. Sand mining in South Africa is controlled by a complex regulatory system that can be distilled into three main themes: mineral regulation; environmental regulation; and land use planning regulation. In this thesis, it is hypothesised that sand mining is subject to all three regulatory themes equally. In practice, however, the regulatory system is skewed in favour of mineral regulation with the effect that the latter two themes are effectively ignored by sand miners.
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Kim, Tae-Goun. "Managing marine resource use conflicts : marine sand mining in Korea /." View online ; access limited to URI, 2007. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3284825.
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Stark, Aimee Lizabeth. "Characterization of sand processed for use in hydraulic fracture mining." Thesis, University of Iowa, 2016. https://ir.uiowa.edu/etd/3195.
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Each hydraulic fracturing well uses up to 5,000 tons of silica-containing sand, or proppant, during its operational lifetime. Over one million wells are currently in operation across the continental United States. The resulting increase in demand resulted in the production of 54 million metric tons of sand for use as hydraulic fracturing proppant in 2015.
The goal of this study was to determine the relative risk of occupational exposure to respirable crystalline silica to workers performing tasks associated with mining, processing, and transport of proppant. Sand samples were aerosolized in an enclosed chamber. Bulk and respirable samples were submitted to a commercial lab for silica analysis. A risk ratio was calculated by comparing respirable dust concentrations to the current occupational safety regulations.
Raw sand produced higher concentrations of respirable dust and a higher risk ratio (3.2), while processed dust contained higher percentages of respirable crystalline silica but a lower risk ratio (0.5). When vibration was introduced prior to aerosolization, concentrations tended to increase as vibration times increased, resulting in an increase of the associated risk ratio (2.3). Results of the study indicate that workers in sand mines and workers exposed to proppant that has undergone low-frequency vibration are at increased risk of exposure to respirable crystalline silica compared to workers who are exposed to proppant that has not undergone vibration.
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Wang, Jun. "The stress-strain and strength characteristics of Portaway Sand." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/10170/.
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Despite the large number of modifications proposed to the standard Cam-clay models over the last three decades, the critical state concept has been much less successful for modelling sand behaviour. This thesis is concerned with understanding the stress-strain and strength characteristics of Portaway sand, a quartz sand, and the validity of several recently developed critical state models formulated in terms of the state parameter concept. The laboratory investigation consisted of the evaluation and modification of two triaxial systems and 83 triaxial tests performed under monotonic and cyclic loading conditions. Emphasis has been placed on assessing the applicability of critical state theory and state parameter concept to sands. Portaway sand was chosen in this research work because it is a typical granular material for which the deformation behaviour can be obtained and used to verify the newly developed constitutive models. The critical state model concerned is known as CASM developed by Yu (1995, 1998). CASM is a relatively simple model because it only requires seven model constants, five of which are the same as those used in the modified Cam-clay model. Three extensions of CASM referred to as CASM-b, CASM-d and CASM-c were developed recently based on the combined hardening concept and the bounding surface plasticity theory. These enable the smooth transition of stiffness, phase transformation and cyclic behaviour to be simulated. For the first time, a simple procedure for determining all the model parameters from triaxial results has been established. The validities of the theoretical assumptions introduced in the new models are critically assessed in light of results obtained from both element testing and numerical modelling. In general, the overall stress-strain behaviour of Portaway sand observed in triaxial tests under various stress paths is well captured by the models.
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Neary, Daniel G., and Pablo Garcia-Chevesich. "Hydrology and Erosion Impacts of Mining Derived Coastal Sand Dunes, Chañaral Bay, Chile." Arizona-Nevada Academy of Science, 2008. http://hdl.handle.net/10150/296690.
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Talbert, Meredith Corea. "Understanding Sand Mining on the Maha Oya: The Conflict Between Economic and Environmental Survival." PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/522.
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River sand mining from the Maha Oya is the main source of income and a force that drives economic activity for residents along the river. This study takes place in Sri Lanka, there are three villages included in this project: Jambugaswatte, Janituspuraya and Thoppuwa. In Sri Lanka, sand serves as the main building material. It is used to make bricks, tiles, asphalt and concrete, therefore demanding a high market value. However, the over-extraction of sand comes along with significant environmental problems. These communities depend on the river in many ways and the health of the river directly corresponds to the health of the ecosystem as a whole. Along the Maha Oya two important elements of survival are in conflict with one another: residents simultaneously need a healthy, thriving ecosystem to live in, as well as economic opportunities. With support from the Environmental Foundation Ltd. (EFL)--a Sri Lankan environmental justice NGO--this study focuses on the complex situation with sand mining on the Maha Oya. Data for this study comes from fifteen formal interviews with a Sinhala-English translator. These interviews are used to address the two research questions for this project: how do village residents along the Maha Oya perceive sand mining? And what are the emotional, practical and theoretical responses of village residents to the effects of sand mining on their local ecosystems? In order to envision a sustainable future, it is vital to begin with a clear understanding of community perceptions of these complex issues, which are at the heart of this project.
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Silva, Michel Willyam Paixão da. "Modelagem e caracterização de uma jazida de areia do município de Igarassu-PE." Universidade Federal de Pernambuco, 2014. https://repositorio.ufpe.br/handle/123456789/16655.
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CAPEs
Este trabalho apresenta a modelagem e caracterização de uma jazida de areia e analisa a viabilidade técnica da mesma, para que a areia seja utilizada como agregado para construção civil. A jazida mineral está localizada às margens da rodovia federal BR-101, à noroeste do município de Igarassu, região metropolitana do Recife-PE e pertence a uma mineração local. Primeiramente, foi realizada uma pesquisa mineral no local do depósito, através de levantamentos geológicos, levantamentos topográficos e sondagens, para cubagem do mesmo. Em seguida, foram efetuadas várias análises físicas e químicas das características do material a ser extraído, tais como: caracterização e qualidade, análises granulométricas, análise química semi-quantitativa e análise de difração de raios-X. Na sequência, foi executada a modelagem geológica do corpo mineral, através do software DATAMINE STUDIO 3.0, para avaliar o seu potencial, sua dimensão e a viabilidade da lavra. Além disso, foram fornecidos subsídios para a elaboração de um projeto do empreendimento mineiro a ser implantado: lavra, carregamento e transporte, beneficiamento (com uma unidade de classificação) e os principais equipamentos necessários para este empreendimento. A partir dos resultados obtidos, constatou-se a viabilidade da areia para ser utilizada como agregado miúdo na construção civil, com a necessidade do tratamento prévio da mesma para se adequar as normas da ABNT, e obteve-se um volume médio de cerca de 7,5 milhões de metros cúbicos, ressaltando a exequibilidade da exploração da jazida com uma vida útil de aproximadamente 60 anos, para uma produção média de 25.000 m³/mês.
This work presents the modeling and characterization of a sand mine and analyze the technical feasibility of the same, so that sand be used as aggregate for civil construction. The mineral deposit is located on the edge of federal highway BR-101, to the northwest of the city of Igarassu, metropolitan area of Recife-PE and belongs to a local mining. First, a mineral survey was conducted at the site of deposit, through geological surveys, topographical surveys and drilling to cubage the same. Then, they were made several physical and chemical analysis of the characteristics of the material to be extracted, such as: characterization and quality, granulometric analyses, semi-quantitative chemical analysis and diffractometry analysis of X-ray. Following, it was executed the geological modeling of the mineral body, through datamine STUDIO 3.0 software to assess their potential, their dimension and viability of the mining operation. In addition, subsidys were provided for the elaboration of a mining project design to be implemented: mining, loading and transportation, beneficiation (with a classification unit) and the main equipment needed for this project. From the results, the feasibility of sand was found to be used as kid aggregate in civil construction, with the need for pretreatment of the same to suit the ABNT, and obtained an average volume of about 7,5 million cubic meters, emphasizing the exequibility of deposit exploration with a lifespan of about 60 years, to an average production of 25,000 m³/month.
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Davey, Stephen. "Environmental governance of sand mining in an urban setting : Macassar Dunes, Cape Town, South Africa." Master's thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/4842.
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Includes bibliographical references.Sand is a resource in high demand for urban expansion and development. Sand mining operations are often located on the edges of cities. The Macassar Dunes are an important source of building sand for the City of Cape Town. The area is located within the Cape Floral Kingdom, the smallest and richest of the six floral kingdoms of the world. The Macassar Dunes area has been identified as a core flora conservation site due to its unique habitat diversity and quality. South Africa is a developing country and this case study is used to highlight the tensions that arise between the need to provide building sand for development and the need for integrated and accountable management that allows for the sustainable functioning of natural physical and ecological processes as well as enhanced social and economic benefits for people.
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Zhu, Qian [Verfasser], Michael [Gutachter] Bollig, and Pelican [Gutachter] Michaela. "River Sand as a Disputed Resource: A Case of Illegal Sand Mining Near Zhuang Villages in Southwest China / Qian Zhu ; Gutachter: Michael Bollig, Pelican Michaela." Köln : Universitäts- und Stadtbibliothek Köln, 2020. http://d-nb.info/121624118X/34.
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Schroeder, Philip D. "Restoration of Prime Farmland Disturbed by Mineral Sand Mining in the Upper Coastal Plain of Virginia." Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/36588.
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Economic deposits of heavy mineral sand were identified in the late 1980's under prime farmland along the Upper Coastal Plain of Virginia. Mining in Virginia will commence in 1997 on the Old Hickory Deposit in Dinwiddie/Sussex Counties. Experiments were established on two mine pits representing two likely pit closure scenarios; regrading the surface with unprocessed subsoil (Pit 1) or filling to the surface with processed material (Pit 3). To evaluate topsoil replacement vs. organic amendment, each pit was split into two experiments, and an adjacent undisturbed control was established. One half of each pit was covered with approximately 30 cm of topsoil, and the other half of each pit received 112 Mg ha of yard waste compost. The -1 experiment was double-cropped with wheat ( Triticum vulgare) and soybeans (Glycine max) in 1995/1996. The control and Topsoil treatment on Pit 1 produced the highest wheat yield, but soybean yield was highest on the Control and the Topsoil and Compost treatments on Pit 3.
Wheat yield was positively related to root length, while soybean yield varied with soil bulk density. Soybean rooting was found throughout all horizons in the undisturbed soils, but was limited to the surface 20 to 40 cm in all mine soil treatments. Very wet weather masked treatment effects in both crops, but the physical and chemical properties of the mine soils indicate that the key to reclaiming these areas lies in effective remixing of mined materials, and developing and maintaining soil humus levels.Master of Science
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Herath, Dulana Nilupul. "Fire impacts on restored shrublands following mining for heavy minerals near Eneabba, southwestern Australia." Curtin University of Technology, Department of Environmental Biology, 2008. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=116352.
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Following mineral-sand mining in the northern sandplains near Eneabba, southwestern Australia, rehabilitation managers have the difficult task of restoring shrubland communities of exceptional plant species richness. Management aims to restore a fully functional and self-sustaining shrubland community with similar vegetation and resilience properties to that of the surrounding natural vegetation. This thesis examines the performance of the restoration program by Iluka Resources Ltd. (and their predecessors) by comparing current vegetation properties and their response to fires on previously mined land versus the surrounding natural shrubland. As biomass accumulates post-restoration, fires will return as a natural disturbance factor and, as a result, a desirable measure of restoration success might include the ability of the postmined lands to recover from disturbance. Pre-burnt plant species diversity, composition, structure and key functional attributes in four mined sites rehabilitated 8 (R8) to 24 (R24) years ago were compared with those of surrounding natural areas classified on the basis of substrate type (low and high sand dunes, shallow sand swales, sand over laterite and sand over limestone). The rehabilitated sites (except R8) had more species (about 140) than natural sites (about 100) with 12–37% species in common with natural sites. Floristic composition was most similar to the local swales and dunes (physically closest).Two strong colonizers, the fire-killed Acacia blakelyi and the fire-tolerant Melaleuca leuropoma, were universally present. Plant densities were about a quarter to half those of natural sites. Fire-resprouters were under-represented. Growth-form distributions were most similar to those of the dunes, with some woody shrubs up to 2.5 m tall present. Greater iron levels and soil hardness (penetrability) were the only soil factors consistently greater in rehabilitated sites. Following experimental fires at the same study sites, species richness fell by 22–41% in rehabilitated sites but increased by 4–29% in natural sites. Species present before fire were reduced by 40–56% in rehabilitated sites and 4–12% in natural sites. Only 42–66% of resprouting species recovered in rehabilitated sites, whereas 96–100% recovered in natural sites. Nonsprouting species recruitment was also lower in rehabilitated (18–57%) than natural (67–85%) sites. Seedling mortality over the first summer after fire was higher in rehabilitated sites (59-86% death of individuals) than in natural sites (14-60%). PCoA ordination showed that fire altered the floristic composition of rehabilitated sites much more than it did in natural sites, mostly attributable to the loss of the extant resprouter species. It was found that the smaller lignotuber size (source of dormant buds) recorded in rehabilitated (vs. natural) resprouters was responsible for their higher post-fire mortality. For equivalent crown size in ten common lignotuberous shrub species, lignotuber circumferences were, on average, 50% smaller at rehabilitated sites.
As a result, overall persistence in these species was much lower in rehabilitated (mean of 52% alive, range of 11–93%) versus natural sites (mean of 96%, range of 79–100%), but improved with time since restoration for five of the ten selected species. Apart from differences in the age of the plants (natural sites having much older plants recruited after previous fires), the lower soil penetrability at rehabilitated sites may have restricted lignotuber development. A tradeoff favoring a higher crown volume to lignotuber size ratio was also apparent in nine of the ten species with greater crown volumes (by 37%) and smaller lignotubers (by 36%) in rehabilitated sites. Demographic attributes for six selected woody species were compared between rehabilitated and natural sites (~3-30 years since disturbance) to investigate growth patterns and optimum fire-return intervals. At matched years since restoration or last fire, nonsprouter species in rehabilitated sites grew larger (1.1 to 4.7 times) and produced/stored more viable seeds per plant (1.1 to 10.9 times). Despite older aged individuals in natural sites at matched years since restoration vs. last fire, restored resprouters were larger (1.1 to 3.6 times) and produced/stored more viable seeds (1.1 to 6.9 times). Although greater growth and fecundity rates were recorded in rehabilitated sites, the estimated optimum fire-return interval based on maximum seed production was similar in rehabilitated and natural sites for five out of six species.
However, mean fire intervals typical of surrounding natural vegetation near the Eneabba area (13 years over the last 40 years) may not be suitable for rehabilitated minesites at Eneabba, whereby longer initial fire intervals (20–30 years) would better ensure persistence of resprouter individuals via the seedling recruitment strategy and resprouting strategy. Iv My study indicated that the returned vegetation can at present be classified as “rehabilitated” or “partially restored” but not “completely restored” since the original plant diversity, composition, structure, and resilience properties to fire have not yet been achieved. It may not be possible/realistic to achieve complete restoration since mining is such a destructive disturbance type that some complex ecological attributes may take centuries to develop. I discuss six key factors as important in improving the overall restoration success at Eneabba: 1) restoration of a deeper topsoil and looser subsoil profile; 2) collection of appropriate amounts of only local provenance species, mulch and topsoil; 3) control of highly competitive species; 4) management of fertilizer additions; 5) reseeding and replanting in subsequent years after the initial restoration treatments, including after initial fires; and 6) delaying the introduction of management fires until the restored vegetation develops sufficient fire-resilience properties.
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Oiffer, Alexander. "Integrated Solid Phase, Aqueous Phase and Numerical Investigation of Plume Geochemistry at an Oil Sand Mining Facility." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/1210.
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A plume of process-affected groundwater was identified in a shallow sand aquifer adjacent to a tailings impoundment at Syncrude Canada Ltd. Quantitative and qualitative Naphthenic Acid (NA) analyses were performed on groundwater samples to investigate NA fate and transport properties in the subsurface. Analysis of dissolved organic and inorganic components was undertaken to identify, quantify and assess the mobility of other dissolved components of environmental significance. NAs at concentrations up to 87 mg/L were found to represent the major contributor to aquatic toxicity. Attenuation of NAs by biodegradation is not observed based on screening techniques developed to date. Retardation of NAs observed at the field scale, is consistent with weak sorption observed in the laboratory by other authors. Concentrations of ammonium approached 4 mg/L in the plume, however mobility is limited by cation exchange. Aromatics and trace metals are present in low quantities (i. e. <10 µg/L) and are only detected in groundwater immediately adjacent to the toe of the tailings impoundment. Cl and Na are found at concentrations of up 282 and 579 mg/L respectively. Dissolved oxygen is typically < 1 mg/L within the plume, while redox indicators Mn(II), Fe(II) and methane are detected between <0. 1 - 2. 6, 0. 2 - 3. 5 and <0. 1 - 2. 1 mg/L respectively within the plume. Solid phase geochemistry, determined through solid phase extractions, was coupled with aqueous geochemistry and reactive transport modeling to identify the dominant geochemical processes occurring within the plume. Based on scenarios evaluated using reactive transport modeling, the most likely origin for the presently observed, weakly reducing conditions in the plume appears to be the presence of a small amount of disssolved, degradable organic carbon. The dominant terminal electron acceptors appear to be Fe(III) and Mn(III/IV) in the plume core and dissolved oxygen at the plume fringe. Dissolved Fe and Mn are observed to enter the domain at the upgradient boundary at maximal concentrations of 4. 2 and 0. 7 mg/L respectively. Trace metal geochemistry of the aquifer material was also assessed using solid phase extractions. The potential for trace metal release via reductive dissolution of the native geologic material is considered minimal in this case, based on the weakly reducing nature of the plume and a lack of excessive trace metal content in the aquifer material.
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Gosling, Christine, University of Western Sydney, and School of Civic Engineering and Environment. "Co-disposal of rejects from coal and sand mining operations in the Blue Mountains : a feasibility study." THESIS_XXXX_CEE_Gosling_C.xml, 1999. http://handle.uws.edu.au:8081/1959.7/824.
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This thesis presents details of investigations into the potential for co-disposal of the two rejects from Clarence Colliery and Kable's Transport Sand Mine. Column experiments were undertaken to simulate field conditions. The experiment consisted of: 1/. creating the required co-disposal arrangement and structure in containers 2/. infiltrating water through each container and measuring the rates of infiltration and overflow 3/. measuring the chemical properties of the leachate water. Geotechnical tests of co-disposal pile stability were undertaken using a specially constructed shear box. Results of this study suggest the co-disposal of course coal washery reject from Clarence Colliery with clay tailings from Kable's Transport Sand Mine is a feasible option for managing the generation of acetic drainage. It is recommended that field trials comprise layers of coal reject and clay tailings in a 9:1 ratio. Layering the coal reject with clay tailings creates a semi-permeable barrier which acts to restrict water percolation through the reject as well as reacting with the leachate to increase the leachate pH and adsorb metalsMaster of Engineering (Hons)
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Gosling, Christine. "Co-disposal of rejects from coal and sand mining operations in the Blue Mountains : a feasibility study /." View thesis, 1999. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030822.133548/index.html.
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Palha, Mirian PerpÃtua e. Silva. "The Production Process in Mining Sand River in Poti in Teresina - PiauÃ: a look at the Health, Work and Environmental." Universidade Federal do CearÃ, 2006. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=4645.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoThis descriptive and cross-sectional survey was designed to evaluate the workersâ health, including occupational risks factors, and the environmental damages caused by sand mining, using hydraulical dredges, on the banks and the riverbed of the Poti river, in Teresina, in Northeast Brazil. Twenty-one dredges were visited, and 18 owners or managers and 75 workers were interviewed. Their main roles were divers, provided manual labors, engine operators, machine operators and administrators. The study showed that the potential risks for workersâ health, included physical, ergonomics, chemical, biological and accidental risks. The most important diseases related to the tasks were respiratory infections, back pain, dermatosis, and clinical manifestations related to barotraumas; the latter occurring only in those who worked as divers performing standard diving. Reports of fatal accidents with divers, and swimmers drowning who had not succeeded in leaving deep holes in the riverbed were also discovered. Serious environmental damages caused by this economical activity were demonstrated, mainly deforestation of the marginal vegetation on the riversides, contamination of the river water with petroleum derivatives, and the development of deep holes in the riverbed. Besides this, the exhaustion of the sand reserves (after an average period of four years of dredging in each explored area) demanded constant movement of dredges along the Poti riverbed, contributing to the gradual deterioration of the environment in the surrounding neighborhoods. In spite of the existence of an environmental legislation, and the action of regulating agencies, little has been done for an appropriate re-vegetation program of the degraded areas. In general, the main actions of the dredges owners, aimed at the recovery of the degraded environment, had been: to keep the minimum distance of the sand box at least 100 meters from the river banks, obeying the environmental preservation zones, and the construction of narrow channels for water draining back into the river. These measures, even so prospicious, are still far from accomplishing the restoration of environmental damages caused by sand dredging of the Poti River.
Este estudo descritivo, observacional e transversal foi conduzido com o propÃsito de avaliar riscos à saÃde dos trabalhadores da atividade de mineraÃÃo de areia, que utiliza dragas hidrÃulicas, nas margens e leito do rio Poti, no municÃpio de Teresina â PiauÃ, bem como detectar danos ao meio ambiente decorrentes desta atividade econÃmica. Foram visitadas vinte e uma dragas em operaÃÃo na Ãrea do estudo e entrevistados 18 proprietÃrios ou prepostos e 75 trabalhadores, todos do sexo masculino, que desempenhavam atividades de mergulhador, caixeiro, operador de motor-bomba, operador de retroescavadeira e administrador. As avaliaÃÃes qualitativas e quantitativas indicaram que os potenciais riscos à integridade fÃsica dos trabalhadores foram os riscos fÃsicos, ergonÃmicos, quÃmicos, biolÃgicos e de acidentes. Os principais agravos à saÃde detectados incluÃram infecÃÃes respiratÃrias, dorsalgias, dermatoses e manifestaÃÃes clÃnicas relacionadas com barotrauma; estas Ãltimas ocorrendo dentre aqueles que realizavam mergulho raso dependente (standard diving). Foram tambÃm resgatados relatos histÃricos de acidentes fatais com colaboradores da Ãrea de prospecÃÃo de areia, como tambÃm afogamento de banhistas que nÃo conseguiram vir à tona apÃs cair em grandes buracos no fundo do rio. Diversos danos ao meio ambiente foram observados, notadamente desmatamentos da vegetaÃÃo ribeirinha nas margens do rio, contaminaÃÃo da Ãgua do rio por derivados do petrÃleo, e a formaÃÃo de buracos profundos no leito do rio. O esgotamento das reservas extrativistas (apÃs perÃodos de dragagem com duraÃÃo mÃdia de quatro anos em cada Ãrea explorada) exigia ainda constante movimentaÃÃo das dragas ao longo do leito do rio Poti, contribuindo para a progressiva deterioraÃÃo ambiental nas proximidades das suas margens. A despeito da existÃncia de legislaÃÃo ambiental e da aÃÃo de ÃrgÃos reguladores, pouco tem sido feito para um apropriado e efetivo programa de re-vegetaÃÃo das Ãreas degradadas. Em geral, as aÃÃes dos proprietÃrios de dragas visando à recuperaÃÃo do meio ambiente foram: manter distÃncia mÃnima do caixÃo de areia de pelo menos 100 metros a partir da margem do rio, em obediÃncia Ãs zonas de preservaÃÃo ambiental, e a construÃÃo de canaletas para drenagem da Ãgua a ser retornada para o rio. Estas medidas, embora promissoras, ainda estÃo longe de cumprir, isoladamente, a funÃÃo de restauraÃÃo dos danos ambientais decorrentes da atividade de mineraÃÃo de areia por dragagem no leito do rio Poti.
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Nunes, Junior Mario da Silva. "Valoração ambiental : casos da mineradora Viterbo Machado Luz." [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287118.
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Orientador: Rachel Negrão CavalcantiDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias
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Resumo: Nas últimas décadas o debate econômico envolvendo questões como a utilização intensiva de recursos naturais (faunísticos, florísticos, hídricos, minerais, etc.) e as graves conseqüências sócio-econômicas geradas pela poluição do meio ambiente têm posto a relação Homem-Natureza no centro das atenções econômicas. Para que sejam propostas soluções economicamente viáveis para problemas ambientais como esses é necessário entender como a economia, enquanto campo do conhecimento, desenvolve este debate através de seus interlocutores (agentes econômicos). Pela lógica econômica os valores econômicos atribuídos aos recursos naturais são determinados pelo seu valor de uso direto. Em relação a bens minerais como a areia, este valor de uso direto é relacionado a sua importância como agregado mineral na construção civil. Com os avanços do debate econômico sobre o meio ambiente, outros valores, além desse estimado pelo uso direto da areia, passaram a ter destaque nas análises econômicas, principalmente através das técnicas de valoração ambiental que possibilitam a mensuração do valor de uso indireto, ou seja, dos valores econômicos atribuídos aos serviços ambientais desempenhados por este bem mineral, a areia. O presente trabalho tem por objetivo mensurar o valor de uso indireto da areia explotada pela Mineradora Viterbo Machado Luz (MVML) instalada em uma área de proteção de mananciais da Região Metropolitana de São Paulo. A escolha dessa mineradora foi em função de seu destaque enquanto modelo de mineração ambientalmente responsável. A determinação do valor de uso indireto contou com a colaboração dos clientes da Mineradora que compunham um universo passível de ser mensurado e entrevistado. Pôde-se concluir que o valor de uso indireto da areia tem um maior sentido quando utilizado como parâmetros para políticas de comando e controle, baseadas na aplicação de multas e indenizações por danos ambientais ou mesmo na elaboração de políticas de incentivos econômicos
Abstract: ln the last decades, the economic debate concerning to questions such as intensive utilization of natural (faunistic, floristic, hydric, mineral etc.) resources, and the serious socio-economic consequences generated by the pollution of the enviromment has put the relation Man-Nature in the centre of the economics attention. In order to propose the economically viable solutions to the environmental problems as these, it is necessary to understand how the economy as field of knowledge develops this debate through its interlocutors (economical agents). Through the economic logic the economical values imputed to the natural resources are determined by its direct use value. In relation to the mineral goods like sand, this direct use value is related to its importance like mineral agregated at the civil architecture. With the improvement of the economic debate about the environment, other values, add to that estimated by direct use of the sand, had passed to have notability in the economic analysis, mainly, through the techniques of environmental valoration that becomes possible the measuring of the indirect use value, that is, of the economic values imputed to the environmental services performed by the mineral good, the sand. This work has as goal to measure the indirect use value of the exploited sand by the Mineradora Viterbo Machado Luz (MVML) settled in a protection area of fountainheads ITom the Metropolitan Region of São Paulo. The choice of this mining was in function of its notability as model of environmentally responsible mining. The determination of the indirect use value counted with the colaboration of the clients ITom the mining who compose an universe susceptible to be measured and interviewed. It is possible to conclude that the indirect use value of the sand has a greater sense when it is used as parameters to the comand and control politics, based in the aplication of fines and compensations by environmental damages or even in the elaboration ofthe politics of economical incentives
Mestrado
Administração e Politica de Recursos Minerais
Mestre em Administração e Politica de Recursos Minerais
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Almeida, Raquel Olimpia Peláez Ocampo. "Revegetação de áreas mineradas: estudo dos procedimentos aplicados em minerações de areia." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-19022004-164619/.
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Este estudo analisa os métodos e técnicas utilizadas na revegetação de áreas de mineração de areia, e avalia os resultados que vem sendo obtidos. Foram visitadas cinco minerações típicas do setor contendo áreas revegetadas, nas quais observou-se o conjunto das atividades de recuperação. De forma geral, a revegetação vêm cumprindo papel fundamental na recuperação das áreas mineradas. Para uma avaliação mais detalhada, numa segunda fase do estudo, selecionou-se duas minerações: Viterbo Machado onde houve revegetação com espécies nativas em área de disposição de rejeito e; Cinco Lagos onde foi executada revegetação em antiga área operacional visando a recuperação de mata ciliar. Para avaliar os resultados da revegetação, foram selecionados cinco indicadores de desempenho: aspecto visual da revegetação, densidade, altura média de plantas, número de espécies plantadas e mortalidade de mudas. Na Mineração Viterbo, as características do rejeito depositado (finos) dificultam o desenvolvimento normal das plantas. As práticas atuais de manejo amenizam o problema, mas ainda não são suficientes. O tipo de manutenção de uma área revegetada há cinco anos, ainda não permite a regeneração natural, e nem todas as espécies utilizadas estão adaptadas às condições do substrato. Outra área semeada há nove anos só com gramíneas, hoje em dia revela um processo de regeneração natural considerável, embora com número restrito de espécies e distribuição localizada. A revegetação na Mineração Cinco Lagos tem pouca diversidade de espécies, mas apresenta bons resultados de crescimento e regeneração natural, especialmente em área com distanciamento de 6x1m entre linhas e plantas, respectivamente. Alguns aspectos observados do manejo do solo precisam ser aprimorados, e a escolha das espécies deve considerar a adaptação local. O número de espécies usadas para implantação de mata nativa é muito restrito, mas a regeneração natural vem se mostrando decisiva na diversificação de espécies. A revegetação em bacias de decantação requer a incorporação de novas estratégias de manejo do solo e das plantas. O método de avaliação demonstrou-se válido desde que realizado mediante a aplicação de um conjunto de indicadores e tendo em conta as características intrínsecas de cada local. Pesquisas neste campo podem ser aprofundadas com aplicação de indicadores adicionais (por exemplo sobre o estado do solo), e com estudos do aprimoramento do manejo nas suas dimensões técnica e econômica.This dissertation analyses the methods and techniques used to revegetate areas of sand mines and assess the results obtained. In the first phase of study, reclamation activities of five typical sand mines were observed. In general, revegetation in these mines plays a fundamental role in mined areas reclamation. Two mines were selected for a more detailed assessment, namely: Viterbo Machado Mine- where revegetation of decantation ponds has been carried out with native species; and Cinco Lagos Mine- where revegetation was performed in previous operational area aims to recover riparian vegetation. For assessing results, indicators were selected for collecting the following data: visual aspect of vegetation, plants density and number of species per hectare, plants height average and settled plant mortality. In Viterbo Mine, tailings characteristics make difficult the normal plant development. Current practices of soil management diminish this problem, but efforts have not shown to be enough to obtain satisfactory results. The type of maintenance of a five year plantation does not permit natural regeneration, and plant species chosen are not the best suitable. In a nine year grassland sown, nowadays there is a good natural regeneration process but with few number of species. Cinco Lagos Mine presents low planted species diversity but shows good conditions of vegetation growth and natural regeneration, mainly with 6mx1m grid between lines and plant respectively. Some aspects of soil management must be improved and the choice of species has to consider local adaptation. A low number of species are used for restoring natural vegetation, but natural regeneration process has been found is showing to be a decisive factor for diversification of vegetal species. Revegetation practice of decantation pond needs to add new soil and plant management strategies. Results assessment has been done through the application of a set of indicators. New research can be done to test the applicability of additional performance indicators (soil condition, for example).
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Oliveira, Leandro de. "Soil recuperation in forest settlements in mining areas in the Tremembé municipality - SP." Universidade de Taubaté, 2006. http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=77.
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The recuperation of degraded areas due to mining activity namely sand mining is carried out by the forest recomposition with native species. In the present work the availability of nutrients along with amount of living matter cover accumulated in a native ciliary wood and in five fragments of forest recomposition of areas previously used for sand mining in the municipality of Tremembe SP. Such areas are currently at different phases of vegetative development process, ranging from 1, 5 and 11 years. The content of nutrient, organic matter, soil acidity and total
production of living matter cover and coarse living matter leaves ,twigs and roots were analyzed .The living matter cover was sampled in 1 m2 fragments the 0-20 and 20-40 cm layers at five different random points in the beds and between the beds in all areas. The soil samples were analyzed in terms of the attributes pH, organic matter, P, K, Ca , Mg , H , Al , base aggregation , cation exchange capacity and base saturation percentage. The comparison of the living matter cover production and the chemical attributes between the areas were analyzed by means of variance analysis complemented by the Tukey test. A smaller production of total living matter cover was observed in the fragments over 6, 5 reforestation years. As from that period
however, the relation between the content of the organic matter and the amount of living matter cover in the superficial layer of the soil tends to differ. There is an increase in the nature of organic matter and the reduction of the production of living matter cover possibly due to the
cumulative effect of the organic matter in the soil through the organic composts that are more resistant to decomposition and respond for the humus formation. By means of the analyses of the chemical attributes the soils of the forest fragments were classified as dystrophic and moderately fertile. The nature and level of nutrients presented average values for Ca and Mg, high for P and low for K. The higher values for Ca, Mg and P may be a result of the residual effect of the fertilization carried out during the planting process.A recuperação de áreas degradadas devido à exploração mineraria, notadamente pela extração de areia, é realizada pela recomposição florestal com espécies nativas. No presente trabalho analisou-se a disponibilidade de nutrientes e a quantidade de serapilheira acumulada em um fragmento de mata ciliar nativa e em cinco fragmentos de recomposição florestal de áreas anteriormente utilizadas para exploração de areia no município de Tremembé, SP. Estas áreas apresentam-se em processo de desenvolvimento vegetativo com períodos diferentes, variando de 1,5 a 11 anos. Foi analisado o teor de nutrientes, matéria orgânica, acidez do solo e a produção da serapilheira total e fracionada em folhas, ramos e raízes. As serapilheira foi amostrada em parcelas de 1m2, nas camadas 0-20 e 20-40 cm em cinco pontos escolhidos aleatoriamente nas leiras e entre leiras, em todas as áreas. Nas amostras de solo analisaram-se os atributos pH, matéria orgânica, Fósforo, Potássio, Cálcio, Magnésio, Hidrogênio, Alumínio, soma de bases, capacidade de troca catiônica e porcentagem de saturação de base. A comparação da produção de serapilheira e dos atributos químicos entre as áreas foi analisada por meio de análise de variância complementada pelo teste de Tukey. Observou-se menor produção de serapilheira total nos fragmentos a partir de 6,5 anos de reflorestamento. Entretanto, a partir deste período, a relação entre o teor de matéria orgânica e a quantidade de serapilheira da camada superficial do solo tende a diferir, com aumento no teor de matéria orgânica e redução da produção de serapilheira, decorrente, possivelmente, do efeito acumulativo da matéria orgânica no solo através de compostos orgânicos mais resistentes à decomposição responsáveis pela formação do húmus. Por meio das análises dos atributos químicos, os solos dos fragmentos florestais foram classificados como distróficos e de fertilidade moderada. Os teores dos nutrientes apresentaram valores médios para cálcio e magnésio, alto para o fósforo e baixo para o potássio. Os valores mais elevados de cálcio, magnésio e fósforo podem ser decorrentes do efeito residual da adubação realizada na época do plantio.
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Sand, Christian [Verfasser], Jörg [Akademischer Betreuer] Franke, Jörg [Gutachter] Franke, Michael [Gutachter] Amberg, Jörg [Herausgeber] Franke, Nico [Herausgeber] Hanenkamp, Marion [Herausgeber] Merklein, Michael [Herausgeber] Schmidt, and Sandro [Herausgeber] Wartzack. "Prozessübergreifende Analyse komplexer Montageprozessketten mittels Data Mining / Christian Sand ; Gutachter: Jörg Franke, Michael Amberg ; Betreuer: Jörg Franke ; Herausgeber: Jörg Franke, Nico Hanenkamp, Marion Merklein, Michael Schmidt, Sandro Wartzack." Erlangen : FAU University Press, 2021. http://d-nb.info/1232075884/34.
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Miyoshi, Carolina. "Reconstrução ambiental de uma região sob influência antrópica: uma avaliação dos últimos 200 anos do Rio Guaíba (RS)." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/21/21137/tde-31072017-170653/.
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O Antropoceno é marcado pelo aumento da demanda populacional e pelo desenvolvimento industrial. Essas alterações antrópicas têm tido como consequência mudanças ambientais e climáticas, principalmente nos últimos 200 anos. O Rio Guaíba, localizado no Estado brasileiro do Rio Grande do Sul, é considerado de extrema importância por diferentes atributos: (1) principal fonte de abastecimento de água potável para a população de Porto Alegre; (2) importante via de navegação, que liga a região central do Estado com a Lagoa dos Patos e, consequentemente, com o Oceano Atlântico; e (3) abriga o setor industrial da capital Porto Alegre. Este trabalho apresenta como objetivo principal a realização de um estudo de reconstrução ambiental em três testemunhos coletados ao longo do Rio Guaíba. Para atingir este objetivo, determinaram-se níveis de elementos traço (As, Cr, Cu, Ni, P, Pb, Sc e Zn), em conjunto com a geocronologia recente, obtida por meio das atividades dos radionuclídeos 210Pb e 137Cs, utilizando o modelo CRS (Constant Rate of Supply). Foram calculados os índices de geoacumulação: Fator de Enriquecimento, Pollution Load Index e Sediment Pollution Index. As colunas sedimentares G1 e G2 demonstraram resultados que expressam as consequências da mineração de areia que ocorre no rio Jacuí, principal fonte de sedimento para o Rio Guaíba. A partir de aproximadamente 1998, houve uma maior fiscalização das dragas operantes neste rio, e a dinâmica deposicional desses testemunhos foi novamente alterada. A reconstrução realizada no testemunho G3 demonstrou-se diferente das demais. Alterações no perfil granulométrico foram explicadas por eventos climáticos (El Niño e La Niña); e o aumento na concentração de elementos traço, principalmente Cr, Pb, P e Zn, está ligado a possíveis fontes antropogênicas. Neste estudo de reconstrução ambiental, a utilização do modelo CRS, de proxies de metais e da granulometria de finos mostrou-se adequada, principalmente no caso das consequências relacionadas à mineração de areia no rio Jacuí.The new epoch Anthropocene is marked by the increase of population and industrial development. These anthropic alterations have had as consequences environmental and climatic changes, especially in the last two hundred years. The Guaíba River, located at the Brazilian State of Rio Grande do Sul, is extremely important for different attributes: (1) it is the main source of potable water to the capital Porto Alegre; (2) it is an important navigation route, that connects the State central region with the Patos Lagoon and the Atlantic Ocean; and (3) it harbors the main industries of Porto Alegre. The principal objective of this study was to obtain environmental reconstructions for three sediment cores from Guaíba River. To accomplish this goal, we determined the concentrations of trace elements (As, Cr, Cu, Ni, P, Pb, Sc and Zn) and proceeded the analysis of recent geochronology, which was acquired through 210Pb and 137Cs activities with the CRS model. Furthermore, we calculated geoaccumulation indices: Enrichment Factor, Pollution Load Index and Sediment Pollution Index. The sediment cores G1 and G2 presented results that expressed the consequences of the sand mining that occurs at Jacuí River. Approximately after 1998, there has been better control of the dredges that operate on the river and the depositional dynamics were changed again. The G3 reconstruction had different conclusions compared with the others. Grain size alterations were explained by climatic events, like El Niño and La Niña; and the concentration increase of trace elements, mainly Cr, Pb, P and Zn, was connected with possible anthropogenic sources. In this study of environmental reconstruction, the utilization of the CRS model and of metals concentrations and grain size as proxies proved to be adequate, especially in the case of the sand mining at Jacuí River and its consequences.
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Souza, Ariane de. "Avaliação do ciclo de vida da areia em mineradora de pequeno porte, na região de São José do Rio Preto - SP." Universidade Federal de São Carlos, 2012. https://repositorio.ufscar.br/handle/ufscar/4333.
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Previous issue date: 2012-09-21Financiadora de Estudos e Projetos
The mining of sand, although of great socio-economic importance to the national scene, has several negative impacts throughout the production chain. Among some of the interference in the natural environment occurs, soil degradation, air pollution and stress in the fauna and flora. This fact has generated great interest in mechanisms that mitigate or prevent adverse effects on the natural environment, such as the Life Cycle Analysis (LCA), which through mass balances and energy gains can provide socio-economic and environmental. The objective of this research was to evaluate the life cycle of the sand extracted from a riverbed mining in the small region of Sao Jose do Rio Preto in the stages of extraction, processing, storage and transport of sand. For this purpose, the procedures were based on ISO standards 14040 and 14044, which require the determination of he purpose and scope, inventory analysis, environmental impact assessment (conducted through the EDIP method (Environmental Development of Industrial Products)) and interpretation. There was a visit to a mining company to collect information on techniques, technologies and inputs used in the production process. In determining the scope, purpose, system boundaries, scales, functional unit and other details were defined. The other steps involved the standardization of units of measurement, classification of environmental changes, normalization and weighting. As a result, it was found that the higher are the atmospheric emissions of carbon dioxide followed by nitrogen oxides and carbon monoxide, whereas potential environmental impacts are most significant global warming and ozone photochemical formation. So, are recommended as the main mitigating actions: activities aimed at optimizing the extraction of sand, implementation of a program for managing the vehicle fleet and dredges and resizing of centrifugal pumps.
A mineração de areia, embora de grande importância socioeconômica para o cenário nacional, apresenta diversos impactos negativos ao longo de toda sua cadeia produtiva. Dentre algumas das interferências no meio natural, ocorre: a degradação do solo, poluição do ar e estresse na fauna e na flora. Este fato gerou grande interesse por mecanismos que mitiguem ou anulem os efeitos prejudiciais no meio natural, a exemplo da Avaliação do Ciclo de Vida (ACV), que através de balanços de massa e energia pode propiciar ganhos socioeconômicos e ambientais. Assim, o objetivo desta pesquisa foi avaliar o ciclo de vida da areia extraída de leito de rio de uma mineradora de pequeno porte na região de São José do Rio Preto-SP nas etapas de extração, beneficiamento, armazenagem e transporte. Para tanto, os procedimentos metodológicos se basearam nas normas ABNT NBR ISO 14040 e 14044, que requerem a determinação do objetivo e escopo; análise de inventário; avaliação de impactos ambientais (realizado através do método EDIP (Environmental Development of Industrial Products)) e interpretação. Foi realizado um levantamento em mineradora de pequeno porte para coleta de informações sobre técnicas, tecnologias e insumos usados no processo de produção. Na determinação do escopo, o objetivo, as fronteiras do sistema, as escalas, a unidade funcional e outros detalhes foram definidos. As outras etapas envolveram a padronização de unidades de medidas, classificação de mudanças ambientais, normalização e ponderação. Como resultado, verificou-se que as maiores emissões atmosféricas são as de dióxido de carbono, seguidas de óxidos de nitrogênio e monóxido de carbono, enquanto que os potenciais de impactos ambientais mais expressivos são: aquecimento global e formação fotoquímica de ozônio. Dessa forma, recomendam-se como principais ações mitigadoras: atividades voltadas para otimização da extração de areia, implantação de um programa de gerenciamento da frota de veículos e dragas e redimensionamento das bombas centrífugas.
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Tibiriçá, Luciana Gonçalves. "Aspectos econômicos e sociais da mineração em Goiás, com ênfase na extração de areia." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7584.
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The State of Goiás (Brazil) has in the mining activity a relevant source of gathering funds and which is part of its history of occupation and formation of urban networks. The mining activity is administrated by technical criteria defined by the Brazilian Department of Mining Production (as known as DNPM), being environmental licensing a part that integrates them. With the pointed requirements on the environmental legislation, the formal mining exploration has adapted itself in front of the need of conserve/preserve the environment considering the geological and geographical conditions. Present in several industries, the use of mineral resources allows the development of varied goods, moving finance market and creating jobs. From the principles that mining is an activity of wide economic impact, involves environmental problems and that the mining activity of the State of Goiás needs deep researches of characterization, we developed this thesis. The assessment of the several mineral was made by the employment of a methodology in municipal scale, from those with major revenue arising from the mineral compensation due to the extraction of metallic minerals or non metallic more profitable currently for Goiás, beyond the sand considering the period between 2010 and 2014. The results show that in the social aspect, the difference between the main mining municipalities of Goiás is not relevant, even with the contribution from the mineral compensation. For the municipalities producers of sand, the economic impact is minimum and there are difficulties in following the recuperation of degraded areas, because the resource is not enough to enable the manager the actions of local development.
O Estado de Goiás tem na mineração uma fonte de arrecadação relevante e que faz parte de sua história de ocupação e formação das redes urbanas. A atividade mineral é administrada por critérios técnicos definidos pelo Departamento Nacional da Produção Mineral (DNPM), sendo que o licenciamento ambiental é parte integrante dos mesmos. Com as exigências apontadas nas legislações ambientais, a exploração mineral formal tem se adaptado frente à necessidade de conservar/preservar o ambiente considerando as condições geológicas e geográficas. Presente em diversas indústrias, o uso dos recursos minerais permite o desenvolvimento de produtos variados, movimentando o mercado financeiro e gerando emprego. A partir dos princípios de que a mineração é uma atividade de amplo impacto econômico, envolve problemas ambientais e que a mineração goiana necessita de pesquisas de caracterização mais aprofundadas, desenvolveu-se esta tese. Para avaliação dos diversos minérios empregou-se uma metodologia em escala municipal, a partir daqueles com maior receita oriunda da compensação mineral decorrente da extração de minérios metálicos ou não metálicos mais rentáveis atualmente para Goiás, além da areia considerando o período entre 2010 e 2014. Os resultados obtidos demonstram que no aspecto social, a diferença entre os principais municípios mineradores de Goiás não é relevante, apesar do aporte advindo da compensação mineral. Para os municípios produtores de areia, o impacto econômico é mínimo e há dificuldades em acompanhar a recuperação das áreas degradadas, pois o recurso não é suficiente para possibilitar ao gestor as ações de desenvolvimento local.
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Estaiano, João Claudio. "Impactos da mineração de areia em planícies fluviais meândricas da bacia hidrográfica do Alto Tietê: o caso do rio Embu Guaçu, São Paulo - SP." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-13032008-140809/.
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Este estudo apresenta conhecimento geomorfológico sobre sistemas físicos meândricos e, em especial, busca o entendimento das atividades antrópicas sobre estes sistemas físicos, exemplificando assim um dos princípios fundamentais da Antropogeomorfologia ou Geomorfologia Antropogênica. A pesquisa tem como objetivo a análise qualitativa e quantitativa das mudanças produzidas pelas atividades de mineração de areia em um compartimento fluvial da planície meândrica do Rio Embu-Guaçu, setor sul do município de São Paulo (SP). O estudo das mudanças foi realizado com utilização da cartografia geomorfológica evolutiva como recurso analítico das condições do sistema físico em situação préintervenção e após 22 anos de extração de areia (situação durante intervenção). Para tanto, foram produzidos dois mapas geomorfológicos de detalhe da área de estudo: um, referente ao ano de 1981, e representa a morfologia original, o outro, referente à 2003, representa a morfologia antropogênica. A seleção e representação das formas, materiais e processos que constituem os mapas geomorfológicos, bem como sua análise comparativa baseiam-se em um conjunto de geoindicadores considerados como parâmetros para interpretação qualitativa e quantitativa.This study presents the geomorphological knowledge about physical meandering systems and pursuits the understanding of the anthropic activities effects on these physical systems, so characterizing one of the main principles of a anthropogeomorphology and anthropogenic geomorphology. The main purpose of this research was the qualitative and quantitative analysis of the modifications performed by sand mining activities in a fluvial compartment of the meandering floodplain of the Embu-Guaçu river, in the southern sectin Sao Paulo county. This study was performed with the application of evolutionary geomorphological cartography mapping as analytical tool for the physical system conditions in a preintervention situation and after 22 year of sand extraction (state during intervention). Two detailed geomorphological maps were produced: one refers to 1981 and presents the original morphology and the other to 2003 including the anthropogenic morphology. The selection and representation of forms, materials and processes included in geomorphological maps as well as the comparative analysis were based upon a series of geoindicators considered as qualitative and quantitative interpretation parameters.
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Franchi, José Guilherme. "Aplicação de turfa na recuperação de solos degradados pela mineração de areia." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-17122001-110912/.
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A recuperação ambiental de áreas exploradas pela mineração de areia na região do Vale do Paraíba, Estado de São Paulo, constitui anseio popular, obrigação constitucional e fator de diferenciação dentro da mais moderna visão empresarial. Este trabalho estuda a aplicação de turfa como um melhorador de solos na etapa final do processo de recuperação destas áreas: o restabelecimento da vegetação nativa. O interesse surgiu da experiência de trabalho do autor com pesquisa mineral e tecnológica desta substância, além da observação e acompanhamento de alguns projetos de revegetação nestas áreas, tidas como ambientalmente sensíveis e onde os solos apresentam-se, via de regra, improdutivos; sua utilização representou, nestes casos, a diferença entre o sucesso e a necessidade de replantio. Apresenta-se uma revisão bibliográfica sobre turfa e suas propriedades agronômicas, bem como acerca da utilização de matéria orgânica na revegetação de áreas degradadas. O estudo constituiu um comparativo entre resultados de ensaios efetuados em amostras de solo provenientes de área abandonada pela mineração de areia, homogeneizadas em laboratório em seu estado original (branco), de um lado, e com adição de turfa em diferentes proporções, de outro, visando aferir se alguma delas poderia adequar-se mais satisfatoriamente à melhoria das condições gerais do solo em questão. Foram analisadas variações em propriedades químicas e físicas como retenção de cátions, efeito tampão, densidade aparente, condutividade hidráulica e porosidade. Abre-se a possibilidade de os resultados deste projeto não se limitarem apenas à Indústria Mineral mas estenderem-se a outros setores onde haja a necessidade de recuperação de solos, fornecendo subsídios a eventuais modificações no manejo de solos agricultáveis, com perspectivas de geração de economia de recursos em irrigação, fertilizantes e defensivos agrícolas.The environmental recuperation of areas explored by sand mining in the Vale do Paraíba region, in the State of São Paulo, is a popular aspiration, a constitutional obligation and constitutes a differentiating factor in the visions of modern enterprise. This work studies the utilization of peat as a soil conditioner in the final stage of the recuperation process for these areas: the revival of indigenous vegetation. This idea arose from the author's experience in technological and mineral research into peat, coupled with the observation and monitoring of these environmentally sensitive areas, whose soils were, from an agricultural stance, generally unproductive. The utilization of peat, in these cases, represented the difference between success and the necessity for a replantation process. This study presents a review of the agronomic properties of peat as well as the application of organic matter in the revegetation of damaged land. It is a comparative study between laboratory assay results from soil samples in their original state, and those where the soil has variable peat contents, seeking to ascertain which, if any, results in better general conditions for that particular soil. Both physical and chemical properties were analyzed, with an emphasis on cation exchange capacity, buffering, bulk density, hydraulic conductivity and porosity. There is a possibility that the results of this project can extended beyond the Mineral Industry to other sectors, where there are needs for soil recuperation, leading to cost savings for irrigation, fertilizers and agrotoxic compounds in food production areas.
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Pissato, Edilson. "Gestão da mineração de areia no município de Guarulhos: aproveitamento de resíduos finos em cerâmica vermelha." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-10092009-173027/.
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O município de Guarulhos, localizado na Região Metropolitana da Grande São Paulo, possui uma área de 341 km², e população de aproximadamente 1.200.000 habitantes. Apresenta franco crescimento do ponto de vista urbano, o que o coloca como um grande consumidor de matérias primas para a construção civil. A atividade extrativista no município foi muito grande no passado, estando hoje restrita a três minerações de brita, três minerações de areia em atividade, o uma mineração de areia paralizada. As minerações de areia realizam a extração do minério utilizando o processo de desmonte hidráulico, resultando em um resíduo fino composto principalmente por argila. Esta argila atualmente é considerada como rejeito do processo de beneficiamento e descartada em bacias de decantação, quase sempre constituídas pelas antigas cavas de exploração. Ao término da lavra restam as cavas que devem ser recuperadas.O processo de recuperação mais utilizado consiste no tratamento paisagístico e formação de lago para utilização como área de lazer. O objetivo deste trabalho é propor a utilização da argila armazenada nas bacias de decantação (rejeito), assim como das camadas de argila segregadas no processo de extração (estéril) para cerâmica vermelha, prolongando a vida útil da mineração e promovendo um melhor aproveitamento da jazida. Para tal foram realizados ensaios para caracterização da matéria-prima e ensaios cerâmicos. Em um contexto mais amplo, a proposta do trabalho é fornecer parâmetros técnicos e sócio-econômicos para o desenvolvimento estratégico e sustentável da atividade mineral próximo a grandes centros urbanos, integrando-a ao uso do solo municipal e garantindo o suprimento dos recursos minerais industriais imprescindíveis para o desenvolvimento da cidade. É proposto ainda a utilização das cavas de extração remanescentes para disposição dos resíduos inertes oriundos da construção civil, integrada ao Plano de Gestão dos Resíduos da Construção Civil, desenvolvido pela Prefeitura do Município de Guarulhos.The municipality of Guarulhos located in the Metropolitan Region of São Paulo has an area of 341 square kilometers and a population of approximately 1,200,000 inhabitants. It shows frantic urban growth what places it among major consumer centers of raw materials for civil construction. Mining activities in the municipality were of considerable importance in the past, being restricted nowadays to three quarries used for the production of crushed stone and four minings where extraction of sand is carried out. The hydraulic process is commonly used for ore extraction which results in a fine residue made up mainly of clay. This clay, currently considered as a by-product, is discarded in decanting basins which nearly always are old exploitation diggings. When mining exploitation comes to an end, the resultant diggings must undergo landscaping and formation of artificial lakes used as leisure areas. The objective of the proposed work is to make longer the mining lifetime as well as diversify its products through the utilization of the clay stored in the decanting basins as structural ceramics. As a whole the proposal is to present a contribution for the sustainable development of mineral activities near to great centers, currently in conflict with urban growth. Another proposal is to turn exploitation diggings into deposition sites of inert residue originated from civil construction works, this activity being integrated to the Civil Construction Residues Management Plan devised by the City of Guarulhos.
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Rocha, Luciano. "Mineração oceânica: uma alternativa sustentável para o aproveitamento de areias quartzosas." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-14072016-105049/.
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Este estudo apresenta ao Departamento de Engenharia de Minas e Petróleo (PMI) da Escola Politécnica da USP, e também a toda a sociedade, a importância que os oceanos têm com relação às suas riquezas minerais. Pretende ainda mostrar a grande responsabilidade que um empreendimento mineiro no fundo do mar precisa ter, com relação aos impactos ambientais, sendo possível minerar em regiões profundas no oceano promovendo a sustentabilidade. A ideia da mineração oceânica/submarina está ainda sendo amadurecida, este é o momento adequado para se propor metodologias de trabalho submarino sustentáveis; mitigar seus impactos. Este trabalho abrange o tema de maneira ampla, abordando o aspecto histórico, legal, ambiental, bem como questões técnicas de engenharia de minas, como sondagem submarina, caracterização tecnológica, lavra submarina, beneficiamento de minério oceânico e descarte de rejeitos. O trabalho apresenta os passos e resultados de um caso real de exploração oceânica. Trata-se de um estudo para viabilizar economicamente a extração e o beneficiamento de areia marinha, para fins industriais, proveniente da Baía de Guanabara (RJ). O trabalho apresenta desde o planejamento da amostragem no fundo do mar, execução destes trabalhos, caracterização tecnológica, simulação de processo e estudos específicos do uso industrial da areia após beneficiamento. Apresenta ainda uma proposta de rota de processo para a areia marinha e questões ligadas à lavra e ao descarte de rejeitos.This study aims to show the importance of the oceans and its mineral wealth. It intends also to show the big responsibility that an undersea enterprise must bear concerning the environmental impact. It shows the availability to minein a sustainable way in the bottom of the sea. The undersea mining is still raising, now is the auspicious time to suggest sustainably submarine work methodologies; to mitigate its impact. This study covers the historic, legal and environmental aspects, as well as technical issues of mining engineering such as undersea survey, process mineralogy, undersea mining, mineral beneficiation for marine ores and tailings disposal. This study presents the steps and results of a real subsea exploration case. The studied ore is a marine sand from Baía de Guanabara (Rio de Janeiro), aiming to supply industrial market. This is a feasibility and technical study to show how to exploit and process this kind of ore. The study shows the undersea survey planning and its execution, the process mineralogy planning and its results, process simulation and some specific studies to industrial uses for this sand, after its beneficiation. Besides these subjects, the study proposes an industrial process route for process and tailings disposal.
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Vieira, Elisa Hardt Alves. "O licenciamento ambiental de portos de areia da bacia do rio Corumbataí como instrumento para a recuperação de áreas de preservação permanente." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-09052006-153754/.
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Este trabalho avaliou se os instrumentos legais do licenciamento ambiental da extração de areia contribuem para a recuperação das Áreas de Preservação Permanente (APP), além disso, investigou as condições e os recursos dos órgãos envolvidos e o grau de informação dos proprietários. A área de estudo foi a Bacia Hidrográfica do Rio Corumbataí, localizada no Estado de São Paulo. A estratégia de estudo se baseou: a) na análise dos processos de licenciamento ambiental e mineral dos 36 empreendimentos existentes na bacia; b) na análise de campo dos plantios em APP de 21 portos de extração de areia de leito de rio; c) em entrevistas com 15 empreendedores e 15 funcionários dos cinco principais órgãos envolvidos. Foi verificado que a maioria dos órgãos envolvidos apresentam alguma dificuldade na atribuição de suas funções dentro do licenciamento, o que reside principalmente da carência de recurso humano, além da carência de recursos financeiros e materiais e de condições de preparo dos técnicos envolvidos. As irregularidades ambientais e legais dos portos de areia são função de uma soma de fatores, entre eles, a falta de informação e negligência dos empreendedores e a lentidão e os elevados custos do licenciamento ambiental e mineral. A avaliação final mostrou que 52% dos plantios podem ser classificados como ruins, 38% como regulares e somente 10% puderam ser considerados como bom e ótimo. Na maioria das vezes, as técnicas de reflorestamento utilizadas não atenderam aos critérios mínimos para o restabelecimento da estrutura e da função de uma floresta. Foi evidenciado ainda uma situação preocupante de perda de biodiversidade, uma vez que a maioria dos plantios e projetos de reflorestamento possui baixa diversidade em espécies e uma tendência à homogeneidade florística quando comparado com áreas naturais. Chama a atenção o insucesso dos plantios efetivados. Grande parte deles apresentou alta mortalidade, baixa densidade, baixa cobertura do solo por sombreamento da copa, fisionomia florestal sem estrutura vertical bem definida, serapilheira ausente ou escassa e regeneração ausente ou de baixas quantidade e qualidade. Os projetos de recuperação por reflorestamento não são satisfatoriamente cumpridos pelos empreendedores e a maioria mostrou uma listagem florística idêntica a de outros projetos. Além disso, se fossem implementados, na sua maioria, não garantiriam a manutenção da biodiversidade natural das matas ciliares. De acordo com os resultados, pode-se inferir que os atuais instrumentos legais do licenciamento ambiental dos portos de areia não estão contribuindo para a recuperação das APP da Bacia do Rio Corumbataí. Entretanto, o licenciamento ambiental da atividade parece estar contribuindo com a conservação das matas naturais ainda existentes na bacia, em função da atual política ambiental de não desmatamento de novas matas em APP.The purposes of this work were to evaluate whether the environmental licensing legislation for sand mining contributes to the recovery of the riparian vegetation of the Permanent Preservation Areas (river buffer zones), as well as the conditions and resources availability of the involved agencies, and the land owners information level. The study area was the Corumbatai River basin, located in the State of São Paulo. The study strategy involved: a) the analysis of the environmental licensing procedures of the 36 existing mining sites in the river basin; b) field analysis of the seedlings growth in the revegetated areas in the 21 sand mining sites; c) interviews with 15 entrepreneurs and 15 officers of the five main agencies involved. It was observed that most agencies have problems with their own attributions in the licensing process, mainly owing to human resource deficiencies, lack of financial and material resources, and poor conditions for the adequate technical capacitating of the responsible officers. The environmental and legal irregularities of the sand mining sites are due to several factors, such as entrepreneurs misinformation and negligence, slowness and high costs involved in the environmental and mineral licensing. A final evaluation showed that 52% of the revegetation areas could be classified as bad, 38% as regular, and only 10% could be considered good or excellent. Generally, the revegetation techniques used did not meet the minimal criteria for reestablishing the riparian forest structure and function. A worrying situation regarding biodiversity loss was also evidenced, since most of the revegetation projects presented low species diversity and a tendency to floristic homogeneity, as compared to what is observed in natural areas. Most of the revegetated areas showed high mortality rate, low density, little soil cover due to canopy shading, poorly defined vertical structure, absense or inadequate litter and absence or low regeneration quantity and quality. Revegetation projects are not succesfully accomplished by the entrepreneurs and most of them showed an identical floristic list of species to those found in previous projects. Moreover, if such projects were implemented, they would probably not guarantee the maintenance of the natural biodiversity of riparian forests. According to the results, it can be inferred that the current environmental licensing legislation of sand mining sites are not contributing to the recovery of the riparian vegetation in the Corumbatai River basin. However, the environmental licensing of the sand mining activity may seem to be contributing to the conservation of the remaining natural forests in the basin, due to the current environmental policy that prohibities the cutting of riparian forests.
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Blood, Jeremy Russell. "Monitoring rehabilitation success on Namakwa Sands heavy minerals mining operations, Namaqualand, South Africa." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/2310.
Full textAbstract:
Thesis (MScConsEcol(Conservation Ecology and Entomology)--University of Stellenbosch, 2006.Anglo American Corporation’s Namakwa Sands heavy minerals mining and beneficiation operation has been strip-mining a heavy mineral deposit, rich in the commercially valuable minerals ilmenite, rutile and zircon, since September 1994. The mine is located in the vicinity of Brand-se-Baai on the west coast of South Africa, approximately 385 km north of Cape Town. Strip-mining causes total destruction of natural ecosystems through the removal of vegetation and soil in the area where mining is being undertaken. Namakwa Sands has been rehabilitating mined out areas as the mining front moves forward. Due to the difficulty of rehabilitating mined out areas as a result of harsh environmental factors, Namakwa Sands has initiated various research projects to gain an understanding of the baseline conditions and ecosystem function in order to increase plant cover and biodiversity on post-mined areas. This on-going research and the development of rehabilitation and mining techniques have resulted in the implementation of four rehabilitation techniques varying in investment of topsoil replacement, seeding and plant translocation. This study assesses the success and effectiveness of these techniques in terms of various vegetation and soil parameters. In addition, those parameters that are considered useful for monitoring are identified. This study indicated that topsoil replacement and plant translocation facilitate the return of similarity, species richness, species diversity and vegetation cover to post-mined areas. The rehabilitation site that had the greatest amount of biological input (topsoil replacement and plant translocation) appeared to be the most successful technique in facilitating vegetation recovery similar to reference sites. In comparison, the site that had the least amount of biological input performed the worst and requires adaptive management, e.g. reseeding and / or plant translocation. Namakwa Sands should continue to replace topsoil in all future rehabilitation efforts and, when possible (e.g. after sufficient winter rain), continue to translocate species in multi-species clumps. In terms of species selected for translocation, Othonna cylindrica, Ruschia versicolor and Lampranthus suavissimus should be considered for future large-scale translocation projects. Zygophyllum morgsana appears to be more difficult to re-establish under the current climatic conditions (below average rainfall). The long-term viability of rehabilitated Z. morgsana populations needs to be determined before considering this species for any future large-scale translocation purposes. No translocated Asparagus spp. individuals survived and should therefore not be considered for any further translocation purposes. The grass Ehrharta calycina, which is dominant in the site seeded, should continue to be considered for future seeding. Species and functional diversity appear to be the most limiting factors within all the rehabilitation sites and Namakwa Sands will not be able to meet their long-term objective of small-stock farming if diversity and the number of palatable species do not increase significantly. Adaptive management should seriously be considered in order to speed up this process. Alternatively, an appropriate grazing strategy, which is related to the Tetragonia fruticosa dominated vegetation within rehabilitation sites, would need to be determined and adopted.More time is needed to ameliorate the rehabilitated soil profiles to the same level as in reference sites, especially with regard to carbon, pH and sodium levels. In order to increase organic matter within rehabilitation areas, Namakwa Sands should consider creating clumps with cleared vegetation from the mining front. Since the long-term rehabilitation goal has not been achieved, Namakwa Sands will need to continue to monitor plant and soil changes until it has been achieved. The objectives of the current rehabilitation programme are limited and Namakwa Sands should develop additional objectives relating to the structure and function of the natural vegetation. This will give a better indication of whether rehabilitation sites are progressing towards the desired end point and if adaptive management is required. In addition, the current monitoring programme (vegetation survey) implemented at Namakwa Sands could be improved by increasing the vegetation parameters to be monitored. It is recommended that the following vegetation parameters be monitored as part of the long-term monitoring programme: species composition and similarity, species richness, species diversity, vegetation cover, species dominance, vertical structure and functional diversity of the vegetation (clumps and inter-clumps). It is also recommended that carbon, pH and sodium of soil profiles be monitored as part of the long-term monitoring programme. These parameters should not be seen as exhaustive as this study only considered various vegetation parameters and soil chemistry between rehabilitation and reference sites. The results of other studies on the fauna, mycorrhiza, insects, etc. should also be taken into consideration and the monitoring parameters expanded accordingly.
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Bohannon, Stacy Jo. "Hydrogeology of the San Xavier Mining Laboratory and Geophysics Test Site and surrounding area." FIND on the Web, 1991.
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Anderson, Jonathan D. "Impacts of amending bauxite residue sands with residue fines for the establishment of vegetation on residue disposal areas /." Murdoch University Digital Theses Program, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090831.155453.
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Manhique, A. J. (Arao Joao). "Optimisation of alkali-fusion process for zircon sands: A kinetic study of the process." Diss., University of Pretoria, 2003. http://hdl.handle.net/2263/27817.
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Saoudi, Massinissa. "Conception d'un réseau de capteurs sans fil pour des prises de décision à base de méthodes du Data Mining." Thesis, Brest, 2017. http://www.theses.fr/2017BRES0065/document.
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Les réseaux de capteurs sans fil (RCSFs) déterminent un axe de recherche en plein essor, puisqu’ils sont utilisés aujourd’hui dans de nombreuses applications qui diffèrent par leurs objectifs et leurs contraintes individuelles.Toutefois, le dénominateur commun de toutes les applications de réseaux de capteurs reste la vulnérabilité des nœuds capteurs en raison de leurs caractéristiques et aussi de la nature des données générées.En effet, les RCSFs génèrent une grande masse de données en continue à des vitesses élevées, hétérogènes et provenant d’emplacements répartis. Par ailleurs, la nécessité de traiter et d’extraire des connaissances à partir de ces grandes quantités de données nous ont motivé à explorer l’une des techniques conçues pour traiter efficacement ces ensembles de données et fournir leurs modèles de représentation. Cependant, parmi les techniques utilisées pour la gestion des données, nous pouvons utiliser les techniques de Data mining. Néanmoins, ces méthodes ne sont pas directement applicables aux RCSFs à cause des contraintes des noeuds capteurs. Il faut donc répondre à un double objectif : l’efficacité d’une solution tout en offrant une bonne adaptation des méthodes de Data mining classiques pour l’analyse de grosses masses de données des RCSFs en prenant en compte les contraintes des noeuds capteurs, et aussi l’extraction du maximum de connaissances afin de prendre des décisions meilleures. Les contributions de cette thèse portent principalement sur l’étude de plusieurs algorithmes distribués qui répondent à la nature des données et aux contraintes de ressources des noeuds capteurs en se basant sur les techniques de Data mining. Chaque noeud favorise un traitement local des techniques de Data mining et ensuite échange ses informations avec ses voisins, pour parvenir à un consensus sur un modèle global. Les différents résultats obtenus montrent que les approches proposées réduisent considérablement la consommation d’énergie et les coûts de consommation, ce qui étend la durée de vie du réseau.Les résultats obtenus indiquent aussi que les approches proposées sont extrêmement efficaces en termes de calcul du modèle, de latence, de réduction de la taille des données, d’adaptabilité et de détection des événementsRecently, Wireless Sensor Networks (WSNs) have emerged as one of the most exciting fields. However, the common challenge of all sensor network applications remains the vulnerability of sensor nodes due to their characteristics and also the nature of the data generated which are of large volume, heterogeneous, and distributed. On the other hand, the need to process and extract knowledge from these large quantities of data motivated us to explore Data mining techniques and develop new approaches to improve the detection accuracy, the quality of information, the reduction of data size, and the extraction of knowledge from WSN datasets to help decision making. However, the classical Data mining methods are not directly applicable to WSNs due to their constraints.It is therefore necessary to satisfy the following objectives: an efficient solution offering a good adaptation of Data mining methods to the analysis of huge and continuously arriving data from WSNs, by taking into account the constraints of the sensor nodes which allows to extract knowledge in order to make better decisions. The contributions of this thesis focus mainly on the study of several distributed algorithms which can deal with the nature of sensed data and the resource constraints of sensor nodes based on the Data mining algorithms by first using the local computation at each node and then exchange messages with its neighbors, in order to reach consensus on a global model. The different results obtained show that the proposed approaches reduce the energy consumption and the communication cost considerably which extends the network lifetime.The results also indicate that the proposed approaches are extremely efficient in terms of model computation, latency, reduction of data size, adaptability, and event detection
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Sundareisan, Shashidhar. "Making diffusion work for you: Classification sans text, finding culprits and filling missing values." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/49678.
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Can we find people infected with the flu virus even though they did not visit a doctor?
Can the temporal features of a trending hashtag or a keyword indicate which topic it belongs to without any textual information?
Given a history of interactions between blogs and news websites, can we predict blogs posts/news websites that are not in the sample but talk about the ``the state of the economy'' in 2008?
These questions have two things in common: a network (social networks or human contact networks) and a virus (meme, keyword or the flu virus) diffusing over the network. We can think of interactions like memes, hashtags, influenza infections, computer viruses etc., as viruses spreading in a network. This treatment allows for the usage of epidemiologically inspired models to study or model these interactions. Understanding the complex propagation dynamics involved in information diffusion with the help of these models uncovers various non-trivial and interesting results.
In this thesis we propose (a) A fast and efficient algorithm NetFill, which can be used to find quantitatively and qualitatively correct infected nodes, not in the sample and finding the culprits and (b) A method, SansText that can be used to find out which topic a keyword/hashtag belongs to just by looking at the popularity graph of the keyword without textual analysis.
The results derived in this thesis can be used in various areas like epidemiology, news and protest detection, viral marketing and it can also be used to reduce sampling errors in graphs.Master of Science
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Williamson, Christian Thoreau. "Hydrologic mechanisms and optimization of in-situ copper leaching case study-BHP Copper, San Manuel, Arizona /." Diss., The University of Arizona, 1998. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1998_473_sip1_w.pdf&type=application/pdf.
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Lasley, Katrina. "Chemistry and Transport of Metals from Entrenched Biosolids at a Reclaimed Mineral Sands Mining Site in Dinwiddie County, Virginia." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/33994.
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Deep row incorporation of biosolids is an alternative land application method that may allow higher than currently permitted mine land reclamation application rates. Biosolids treated by various processes possess characteristics that uniquely affect metal solubility and mobility due to their influence on metal speciation. The objectives of this research were to compare the effects of biosolids stabilization type and rate on heavy metal solubility, mobility, and speciation. Two rates each of Alexandria, (Virginia) anaerobically digested (213 and 426 dry Mg ha-1) and Blue Plains (Washington, DC) lime-stabilized (329 and 657 dry Mg ha-1) biosolids were placed in trenches at a mineral sands mine reclamation site in Dinwiddie County, Virginia in June and July 2006. Vertical and lateral transport of heavy metals from the biosolids seams were determined by analyzing leachate collected in zero tension lysimeters below the trenches and suction lysimeters adjacent to the trenches. Chloride (Cl-), sulfate (SO42-), nitrate (NO3-), phosphate (PO43-), dissolved organic carbon (DOC), and pH were also determined within the dissolved fractions (< 0.45 µm) collected on September 8, 2006, November 3, 2006, January 5, 2007, June 8, 2007, and September 7, 2007 as input for the speciation program MINTEQA2. Silver, Cd, Pb, and Sn did not move vertically or laterally to any significant extent. Lime-stabilized biosolids produced higher cumulative metal mass transport per sampling period for Cu (967 g ha-1), Ni (171 g ha-1), and Zn (1027 g ha-1) than the anaerobically digested biosolids and control during the 15-month period following entrenching. Barium mass loss was similar for both biosolids. All metals moved primarily with particulates. MINTEQA2 predicted the majority of the metals within the dissolved fraction were present as free ions. As pH decreased and time increased, the amount of association with fulvic acids decreased allowing more free ions and binding with inorganic ligands. Little movement into groundwater demonstrates that anaerobically digested and lime-stabilized biosolids can be land-applied at high rates with little concern of heavy metal contamination of groundwater under these conditions.Master of Science
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Rasor, Bart A. "DATA MINING FOR TECTONIC TREMOR IN THE IRIS PREPROCESSED QUALITY ANALYSIS DATABASE." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1399642220.
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Moeun, Brian. "Toxicokinetics and Bioaccumulation of Metals in Wood Frog Tadpoles (Lithobates sylvaticus) Exposed to Sediment Near Oil Sands Mining in Northern Alberta." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38156.
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Bitumen extraction in the Athabasca oil sands in Alberta releases metals to the
region. In this study, I performed an uptake-elimination experiment with wood frog
tadpoles (Lithobates sylvaticus) to determine the bioaccumulation potential of metals
from exposure to MacKay River sediment, an area affected by oil sands contamination,
and to uncontaminated reference sediment. Wood frog tadpoles, Gosner stages 28-32,
were exposed to two sediments: (1) MacKay River sediment that is enriched in
petrogenic hydrocarbons from natural and anthropogenic sources; and (2) an
uncontaminated reference sediment. Tadpole exposures to sediments lasted 4 days,
followed by a depuration phase for an additional 4 days where tadpoles were allowed to
eliminate excess metals from their bodies. The metal concentrations at various time
points during the uptake and elimination phases were determined in order to define
toxicokinetic parameters, such as uptake and elimination first order rate constants,
accumulation by ingestion, and assimilation efficiencies for specific metals.
It was determined that tadpoles exposed to the MacKay sediment had higher
concentrations of Al, Co, Cu, Cr, Mg, Ni, Pb, V, and Zn throughout the uptake phase of
the study compared to tadpoles exposed to reference sediment. We also observed little to no decrease in concentrations of Al, Co, Cu, Cr, Mg, Ni, Pb, V, and Zn throughout the
elimination phase of the study. In addition, biota-sediment accumulation factors (BSAF)
revealed that Cu, Zn, Cr, and V had among the highest bioaccumulation potential in our
trials. The experiment was subsequently repeated by preventing direct contact of the
tadpoles to sediment with a screen, exposing tadpoles only to metals in water. By
comparing tadpole exposures to metals from ‘aqueous’ and ‘aqueous +sediment’ in separate trials, and by tracking sediment ingestion rates, I am able to show that sediment ingestion constitutes the primary source of metal bioaccumulation by tadpoles. Not only were metal concentrations higher in tadpoles that were ingesting sediment, but they also had greater metal uptake rates compared to tadpoles that were only exposed to contaminated water. It was also determined that assimilation efficiencies were higher in tadpoles exposed to reference sediment compared to ones exposed to MacKay River sediment. Using toxicokinetic parameters defined by the uptake-elimination experiment, I developed a computational model using STELLATM
system dynamics software to accurately estimate first order uptake and depuration rate constants for metals in exposed aquatic animals. The model estimated metal uptake and depuration kinetics with a mean relative error of 2.25 ± 0.93 % (±SE, n=9) for the uptake study and 2.53 ± 2.61 % (±SE, n=9) for the depuration study. With increased oil-sands production anticipated, we recommend continued monitoring of contaminants from oil-sands for the purpose of understanding the potential risks they may have on northern Alberta’s ecosystems.
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Salas, Carreño Guillermo. "Intoxication by mining revenues. San Marcos district politics after twelve years of Antamina’s presence." Pontificia Universidad Católica del Perú, 2012. http://repositorio.pucp.edu.pe/index/handle/123456789/79101.
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Este artículo describe y analiza los procesos de cambio en la políticadel distrito de San Marcos (Huari, Ancash) asociados con lallegada del canon minero —fracción del impuesto a renta pagadopor Antamina— que incrementó súbita y espectacularmente las arcasmunicipales de modo que San Marcos es hoy uno de los distritos másricos del Perú. El texto analiza estos cambios prestando atención alas elecciones municipales de 2006 y a la implementación del PlanPiloto de Mantenimiento de la Infraestructura Pública, que consisteen un programa de empleo temporal. Este último es clave para unanovedosa alianza entre el municipio y los sectores rurales, en particularel llamado Cono Sur, tradicionalmente ausente como actorpolítico importante en el distrito. La política distrital ha dejado deestar dominada por la pugna entre las dos facciones de familias exhacendadas para articularse en una oposición entre los caseríosrurales y el pueblo de San Marcos. La política local ha pasado degirar en torno a Antamina hacia acusaciones, debates y pugnasalrededor de la administración municipal del canon minero. No obstante,las comunidades campesinas que tienen una relación directa con Antamina continúan siendo actores políticos independientes delmunicipio y tienen un peso importante en el distrito.This paper describes and analyses the changes in local politicstaken place in the district of San Marcos (Huari, Ancash) associatedwith the arrival of the Canon Minero – a fraction of taxes paid byAntamina mining company to the Peruvian State. Canon Minero hasincreased sudden and spectacularly the municipality’s funds so muchthat currently San Marcos in «ones of the Peruvian richest districts».The paper pays attention to the municipal elections of 2006 and theimplementation of the Plan Piloto de Mantenimiento de la InfraestructuraPública, a program of temporary work for all San Marcos’citizens. The latter was key for launching a novel alliance betweenthe municipality and the rural population, particularly with the ConoSur composed by hamlets which were traditionally unimportantactors in district politics. Hence, district politics had stopped to bedominated by the struggle between two factions of former landlordfamilies and had become articulated by the opposition between therural hamlets and the town of San Marcos with the emergence ofethnic political claims. Also, local politics ceased to revolve aroundAntamina and has become entangled with struggles over the administrationof Canon Minero. Rural communities which have directnegotiations with Antamina remain important political actors whichare independent from the municipality and are even oppose to it.
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Hughes, Charles E. "The Development of the Smelting Industry in the Central Salt Lake Valley Communities of Midvale, Murray, and Sandy Prior to 1900." BYU ScholarsArchive, 1990. https://scholarsarchive.byu.edu/etd/4810.
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This thesis found that the three communities of Midvale, Murray, and Sandy were the center of the smelting industry in the Salt Lake Valley. These communities became the center of smelting because of their central location, the readily available water supply, and the availability of an inexpensive, efficient transportation system to ship the bullion. The smelters were surrounded by two major mountain ranges which provided a ready supply of good lead, silver, and copper ore.The development of the smelting industry followed three separate phases or periods. The first phase was one of experimentation or period of discovery, in which the smelters operated without the technological skill necessary to be financially successful. The second phase was highlighted by the emergence of skilled German mining engineers who enabled the smelters to be financially successful. Phase three was ushered in during the late nineteenth century by the industrialists who consolidated the smaller smelters and built larger, more efficient plants.
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Brunier, Guillaume. "Côtes sablo-vaseuses sous influence deltaïque de l'Amazone et du Mékong : dynamique morpho-sédimentaire, stabilité et aménagement." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM3112.
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Ce travail de thèse a porté sur l’étude de littoraux sous l’influence de deux grands deltas, l’Amazone et le Mékong, avec un focus sur les plages et cheniers de Guyane intégrant le système de dispersion vaseuse de l’Amazone, et sur les liens entre la déstabilisation du littoral du delta du Mékong et les changements morpho-bathymétriques des chenaux deltaïques sous influence anthropique croissante. L’étude de la plage de Montjoly en Guyane a été conduite en combinant une approche innovante de photogrammétrie aéroportée SfM (Structure from Motion), des mesures hydrodynamiques, bathymétriques, et la modélisation de la propagation des houles à travers cette bathymétrie. Les résultats obtenus montrent le potentiel considérable de la technique de photogrammétrie SfM pour l’étude géomorphologique des plages, et confirment un modèle de rotation de la plage sous l'influence de banc de vase. Le suivi du second site d’étude, un chenier en recul sur un ancien polder rizicole vaseux, au travers d'une analyse multi décennale d’images satellites et des mesures de terrain, a démontré très finement les taux (atteignant 160 m par an) et mécanismes de recul du substrat vaseux en lien avec sa rhéologie.L’analyse de l'évolution de la bathymétrie des chenaux deltaïques du Mékong sur une décennie (1998 et 2008), conduite à travers une méthode sous SIG, a permis de quantifier une perte nette de 200 millions de m3 de sédiments et un approfondissement de chenaux ne relevant pas de processus naturels mais d'extraction de granulats.Ces prélèvements importants de sédiments ont des répercussions importantes sur les apports de sédiments au littoral du delta qui montre des taux d’érosion importantsThis thesis is a geomorphic study of two separate sites associated with two large deltas: the Amazon and the Mekong, with a focus on a beach and chenier in French Guiana integrated into the mud dispersal system of the Amazon, and on the links between destabilization of the Mekong delta shoreline and morpho-bathymetric changes in the deltaic channels under increasing human influence.The study of Montjoly beach in French Guiana was carried out using a combination of an innovative approach in SfM (Structure from Motion) airborne photogrammetry, hydrodynamic and bathymetric measurements, and wave propagation modelling over the nearshore bathymetry. The results show the strong potential of SfM photogrammetry in high-resolution morphometric and sediment budget surveys of sandy beach, and confirm a previously proposed model of beach rotation under mud-bank influence.The second field site in French Guiana, a retreating chenier over a muddy abandoned polder formerly a rice fields, work based on a multi-decadal analysis of satellite images combined with short-term field topographic and hydrodynamic measurements highlighted high rates of chenier migration (up to 160 m a year) and retreat mechanisms over the muddy substrate due to its rheology.A GIS-based analysis of bathymetric changes in the deltaic channels of the Mekong over a 10-year period (1998 to 2008) enabled the quantification of a net loss of 200 million m3 of sediments and an increase in the mean depth of the channels, which appears as unnatural and due to sand mining.These important sediment extractions have serious repercussions on sediment supply to the Mekong delta coast, which shows important rates of erosion
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Rix, Estelle. "Dispersions aqueuses de polyuréthanes bio-sourcés sans isocyanates." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0378/document.
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Les polyuréthanes forment une importante famille de polymère ; ils sont obtenus industriellement à partir d’isocyanates, des dérivés du phosgène. Dans l’optique de s’affranchir de ces composés toxiques et de promouvoir l’utilisation de la biomasse, cette thèse s’intéresse à la synthèse de dispersions aqueuses de polyuréthanes sans isocyanates et dérivés d’huiles végétales. Deux voies de synthèse de polyuréthane sans isocyanate sont étudiées : la transuréthanisation et l’aminolyse des carbonates cycliques. Des synthons biscarbamates et bis-carbonates cycliques dérivés d’acides gras ont ainsi été développés, et leur polymérisation en masse avec des diols ou diamines étudiée. Les deux voies de synthèse permettent d’obtenir des polyuréthanes pour des températures de 20 à 130°C en quelques heures ; le méthanolate de sodium est identifié comme un catalyseur efficace lors de la transuréthanisation tandis que l’aminolyse des carbonates cycliques ne nécessite pas de catalyse. Les masses molaires (Mn) obtenues sont de l’ordre de 5-17kg.mol-1, ces résultats sont cohérents avec la littérature. La polymérisation en mini-émulsion (aqueuse) a alors été utilisée pour la synthèse de polyuréthanes par aminolyse des carbonates cycliques. De nombreuses expériences de formulation des mini-émulsions ont permis d’aboutir à des mini-émulsions et latex de polyuréthanes stablesPolyurethanes are a major polymer family; they are industrially obtained from phosgene derivatives: isocyanates. In order to avoid the use of such toxic compounds and to promote the use of biomass, this thesis investigates the synthesis of aqueous dispersions of nonisocyanate polyurethanes derived from vegetable oils. Two synthesis pathways have been studied; transurethanization and aminolysis of cyclic carbonates. Bis-carbamates and biscyclic carbonates were synthesized from fatty acids, and their polymerizations with diols or diamines were studied in bulk. The two routes allow the production of polyurethanes in a few hours at 20-130°C. Sodium methoxide is used as catalyst for transurethanization reactions while the other synthesis pathway does not require catalysts to proceed. Polyurethanes obtained have molar mass (Mn) around 5-17kg.mol-1, which is in accordance with the literature. The polymerization in aqueous miniemulsion was then investigated for the synthesis of polyurethane by aminolysis of cyclic carbonates. Many formulation experiments were necessary to achieve stable miniemulsion and latex; aqueous dispersions of bio-based non-isocyanate polyurethanes were then obtained
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Kjelleros, Fredrik. "Tjärsandsindustrins miljöpåverkan : Alberta, Kanada." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-28534.
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In Alberta, Canada, amongst its mixture of sand, clay, water and other minerals, the tar sand’s heavy and viscous component bitumen, a thick, sticky form of crude oil is extracted through two methods; open-pit mining for shallower deposits (<75 m), and in situ for deeper deposits (>75 m). This degree project consists of a comparison between these two extraction methods impact on air, nature and water, which all have been evaluated by reviewing and analyzing literature. Studies showed that in situ methods cause a higher impact on air than open-pit mining, through higher emissions of greenhouse gases and sulfur dioxide (SO2), and will surpass the carbon dioxide (CO2) emissions caused by the open-pit mines when the shallower, more accessible tar sands dwindle. Open-pit mining causes a higher impact on water due to its large tailing ponds that causes leakage of processing water and fine tailings, polyaromatic hydrocarbons (PAH: s) and these 13 following elements considered priority pollutants (PPE) by the US Environmental Protection Agency (EPA); antimony (Sb), arsenic (As), beryllium (Be), lead (Pb), cadmium (Cd), copper (Cu), chromium (Cr), mercury (Hg), nickel (Ni), selenium (Se), silver (Ag), thallium (Tl) and zinc (Zn). However studies remain unclear whether or not in situ methods are worse due to underground tailing ponds. Finally, when it comes to nature, open-pit mining causes a more direct environmental impact through deforestation, drainage of peat and wetland, and blasting of rock. In situ methods however, seem to cause more of a long term environmental impact through fragmentation. Dividing the landscape into smaller units through roads, wells, pipelines and seismic lines, leads to domestic biodiversity and homogenization of flora and fauna as unfavorable conditions is created for the nature’s wildlife. In conclusion, in situ methods causes a bigger impact on air than open-pit mining, while open-pit mining causes a bigger impact on water. Due to lack of time and resources, more research about the direct impact on nature is needed to fully evaluate which of the two extraction methods causes the least environmental impact.
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Pauw, Marco Johann. "Monitoring ecological rehabilitation on a coastal mineral sands mine in Namaqualand, South Africa." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17886.
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Thesis (MSc)--Stellenbosch University, 2011.ENGLISH ABSTRACT: The Exxaro Namakwa Sands heavy mineral sands mine at Brand-se-Baai, on the west coast of South Africa, is an important source of income, development and job-creation in the region. However, this comes at a great environmental cost, as strip mining causes large scale destruction of ecosystems through the complete removal of vegetation and topsoil. This is particularly problematic in an environment, such as Namaqualand, where the arid and windy climate, as well as saline and nutrient-poor soils, hamper rehabilitation. These environmental constraints create the need to develop a site-specific rehabilitation program. At Namakwa Sands the objective of rehabilitation is to “rehabilitate and re-vegetate disturbed areas and establish a self-sustaining Strandveld vegetation cover in order to control dust generation, control wind and water erosion, as well as restore land capability. In general, vegetation will be rehabilitated to a minimum grazing standard capable of supporting small stock (sheep) grazing.” In order to achieve this Namakwa Sands conducted rehabilitation experiments with topsoil replacement, seeding of indigenous species and translocation of mature plants. Monitoring is an important part of the rehabilitation process as it allows rehabilitation practitioners to evaluate success and to adapt their management strategies and rehabilitation methods, as well as to evaluate and, if necessary, change their rehabilitation objectives. This study forms part of the monitoring process at Namakwa Sands. It assesses the success of sites that were experimentally rehabilitated in 2001 and a site that was rehabilitated in 2008, using current practice, in order to identify possible management requirements on rehabilitated sites as well as improvements on rehabilitation objectives, methods and monitoring. This study also tests the Landscape Function Analysis (LFA) as rehabilitation monitoring tool by correlating LFA indices with traditional measurements of biophysical variables or their surrogates. Results showed that experimental sites were not successful in returning vegetation cover and plant species richness to the required levels, but did achieve the grazing capacity objective. These sites will need adaptive management to achieve the vegetation cover and plant species richness objectives. The recently rehabilitated site achieved the three-year vegetation cover and plant species richness objectives, as well as the grazing capacity objective, within two years after rehabilitation. Namakwa Sands should therefore continue using the current rehabilitation method. However, rehabilitation should be done in multiple stages in future to decrease the mortality of nursery cuttings and to facilitate the return of late successional species to rehabilitated sites. The sustainability of small stock farming on rangeland with the grazing capacity that is identified as the minimum objective is questionable and this merits further investigation. LFA can be a useful tool to monitor nutrient cycling and soil stability at Namakwa Sands, provided that enough replicates are used. However, LFA cannot be used as is to assess water infiltration at Namakwa Sands, due to assumptions in the calculation of this index that do not hold for the Namaqualand environment. Landscape functioning should be monitored annually to complement vegetation surveys.
AFRIKAANSE OPSOMMING: Die Exxaro Namakwa Sands swaarminerale-sandmyn by Brand-se-Baai, aan die weskus van Suid-Afrika, is ‘n belangrike bron van inkomste, ontwikkeling en werkskepping in die streek. Daar is egter negatiewe omgewingsimpakte aan verbonde, aangesien die strookmyntegniek grootskaalse vernietiging van ekosisteme veroorsaak deur die algehele verwydering van die plantegroei en bogrond. Dit is veral problematies in ‘n omgewing, soos Namakwaland, waar die droë en winderige klimaat, asook die souterige en voedingstof-arme grond, rehabilitasie belemmer. Hierdie beperkings wat deur die omgewing veroorsaak word skep die behoefte om ‘n rehabilitasieprogram te ontwikkel wat spesifiek is tot die terrein. Die doel van rehabilitasie by Namakwa Sands is om te rehabiliteer en herplant op versteurde gebiede en om selfonderhoudende Strandveld plantbedekking te vestig om sodoende stofgenerering te beheer, om wind- en watererosie te beheer, en om grondgebruik-vermoë te herstel. In die algemeen sal plantbedekking gerehabiliteer word tot ‘n minimum weidingskapasiteit wat kleinveeweiding (skaapweiding) kan onderhou. Om dit te bereik het Namakwa Sands rehabilitasie-eksperimente uitgevoer met terugplasing van bogrond, saai van inheemse spesies en oorplanting van volwasse inheemse plante. Monitering is ‘n belangrike deel van die rehabilitasieproses, aangesien dit rehabilitasie-praktisyns in staat stel om sukses te evalueer en om bestuurstrategieë en rehabilitasiemetodes aan te pas, sowel as om rehabilitasiedoelwitte te evalueer en, indien nodig, aan te pas. Hierdie studie vorm deel van die moniteringsproses by Namakwa Sands. Dit assesseer die sukses op persele wat eksperimenteel gerehabiliteer is in 2001 en ‘n perseel wat in 2008 gerehabiliteer is, volgens die huidige praktyk, om moontlike bestuursbehoeftes op gerehabiliteerde persele en verbeteringe aan rehabilitasiedoelwitte, -metodes en –monitering te identifiseer. Hierdie studie toets ook die geskiktheid van die Landscape Function Analysis (LFA) as ‘n rehabilitasie-moniteringsinstrument deur LFA-indekse met tradisionele metings van biofisiese veranderlikes of hul surrogate te korreleer. Resultate dui daarop dat eksperimentele persele nie suksesvol was om plantbedekking en plantspesies-rykdom tot die vereiste vlakke te herstel nie, maar wel die weidingskapasiteit-doelwit bereik het. Hierdie persele benodig aanpassingsbestuur om plantbedekking- en plantspesiesrykdom-doelwitte te bereik. Die perseel wat onlangs gerehabiliteer is, het binne twee jaar na rehabilitasie die drie-jaar plantbedekking- en plantspesiesrykdom-doelwitte, sowel as die weidingskapasiteitdoelwit bereik. Daarom moet Namakwa Sands voortgaan om die huidige rehabilitasiemetode te gebruik. Rehabilitasie moet egter in die toekoms in veelvoudige stadiums gedoen word om die mortaliteit van kwekery-steggies te verminder en om die terugkeer van laatsuksessionele spesies na gerehabiliteerde persele te fasiliteer. Die volhoubaarheid van kleinveeboerdery op weiveld met die minimum vereiste weidingskapasiteit word betwyfel en vereis verdere ondersoek. LFA kan ‘n bruikbare instrument wees om siklering van voedingstowwe en grondstabiliteit te monitor by Namakwa Sands indien genoeg repliserings gebruik word. LFA kan egter nie in die huidige vorm gebruik word om waterinfiltrasie by Namakwa Sands te assesseer nie, aangesien daar aannames in die berekening van die indeks is wat nie juis is in die Namakwaland omgewing nie. Landskapfunksionering behoort jaarliks gemoniteer te word om plantopnames aan te vul.
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Helguera, Arellano Christian. "Contribution à la résolution du problème des minima locaux dans une méthode de planification de trajectoires sans collision pour robots manipulateurs." Poitiers, 2001. http://www.theses.fr/2001POIT2282.
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Bilodeau, Julie. "Toxicokinetics and Bioaccumulation of Polycyclic Aromatic Compounds in Wood Frog Tadpoles (Lithobates sylvaticus) Exposed to Athabasca Oil Sands Sediment." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35847.
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Many polycyclic aromatic compounds (PACs) are toxic, carcinogenic, and mutagenic. As a result, their effects on aquatic biota and ecosystems are of great concern. Research on PACs in aquatic biota often overlooks the role of amphibians, alkylated PACs, and sediment as an uptake route. In order to study the accumulation and toxicokinetics of PACs following sediment and aqueous exposure, and to compare the bioaccumulation potentials of parent and alkyl PACs, two accumulation-elimination experiments using wood frog tadpoles (Lithobates sylvaticus) of Gosner stage 28-32 were conducted (one evaluating exposure to contaminated sediment and water, and the other to contaminated water alone). A complementary field study was then conducted near Fort McMurray, Alberta to assess PAC body burdens in field-collected amphibian larvae, and to determine whether PAC body burdens are related to exposure to sediment and/or water in the field.
The results of our studies showed that PAC concentrations and uptake rates in wood frog tadpoles were highest when they were exposed to PAC-contaminated sediment. Consequently, we determined that the dominant route of exposure of wood frog tadpoles to PACs is sediment rather than water. This finding supports other studies that have shown dietary uptake to be an important route of PAC exposure in other aquatic organisms. In both the laboratory and field study, alkyl PAC concentrations exceeded those of parent PACs in wood frog tadpoles, which also demonstrated petrogenic PAC profiles. Interestingly, parent PACs seemed to have greater bioaccumulation potential than alkyl PACs in the laboratory-exposed wood frog tadpoles (in relation to sediment), possibly due to greater bioavailability or lower metabolism of parent PACs or alternatively, due to a saturation in uptake of alkyl PACs. Nevertheless, only a few compounds, including anthracene, fluoranthene, retene, and C1-benzofluoranthenes/benzopyrenes, were found to have higher bioaccumulation potentials. Lithobates sylvaticus tadpoles seemed to be efficient at eliminating and metabolizing both parent and alkyl PACs. However, the elimination of some compounds, such as C4-naphthalenes, was not as efficient.
Furthermore, C3-fluorenes and C2-dibenzothiophenes were isolated as potential markers of amphibian larvae exposure to PAC-contaminated sediment due to their positive correlation with the wetland sediment concentrations. Additional field collections in the Athabasca oil sands are warranted to verify the utility of these markers in the natural environment. Evidently, this thesis highlights the importance of including sediment exposure and alkylated PACs in toxicological and field studies of benthic and epibenthic organisms. The results of this study are the largest, most comprehensive set of toxicokinetic and bioaccumulation information of PACs (52 analytes) in the amphibian larvae Lithobates sylvaticus obtained to date.
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Dance, Anne T. "Landscapes of perception : reclaiming the Athabasca oil sands and the Sydney tar ponds." Thesis, University of Stirling, 2013. http://hdl.handle.net/1893/16957.
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This interdisciplinary project offers new insights into the reclamation history of two of the most controversial and contaminated sites in Canadian history: the Sydney tar ponds and coke ovens and the Athabasca oil sands. It argues that Canada’s natural resource-dependent economy, combined with jurisdictional uncertainty, created a hesitant, fragmentary site cleanup regime, one that left room for different ideas about landscapes to shape and even distort reclamation’s goals and processes. In the absence of substantive reclamation standards and legislation, researchers struggled to accommodate the unique challenges of the oil sands during the 1960s and 1970s. Ambitious goals for reclamation faltered, and even the most successful examples of oil sands reclamation differed significantly from the pre-extraction environment; reclamation was not restoration. Planners envisioned transforming northeastern Alberta into a managed wilderness and recreation nirvana, but few of these plans were realised. The Sydney tar ponds experience suggests that truly successful reclamation cannot exist unless past injustices are fully acknowledged, reparations made, and a more complete narrative of contamination and reclamation constructed through open deliberation. Reclamation, after all, does not repair history; nor can it erase the past. Effective oil sands reclamation, then, requires a reconsideration of the site’s past and an acknowledgement of the perpetuated vulnerabilities and injustices wrought by development and reclamation.
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Grigg, Alasdair M. "An ecophysiological approach to determine problems associated with mine-site rehabilitation : a case study in the Great Sandy Desert, north-western Australia." University of Western Australia. School of Plant Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0118.
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[Truncated abstract] Establishment of vegetation and ecosystem functioning is central to the mitigation of environmental impacts associated with mining operations. This study investigated the ecophysiological functioning of mature plants in natural vegetation and applied this knowledge to diagnose problems affecting plant health and causes of poor plant cover at a mine-rehabilitation site. Ecophysiological parameters, including plant water relations and mineral nutrition, were studied in conjunction with soil physical, hydraulic and chemical properties. The natural ecosystem at the study location in the Great Sandy Desert is characterised by sand dunes and interdunes with distinct plant communities on each. One of the most notable features of the vegetation is the presence of large Corymbia chippendalei trees high on the dunes and relatively small scattered shrubs in the interdunes. Triodia grasses (spinifex), dominate the vegetation in both habitats but different species occur in each; T. schinzii is restricted entirely to the dunes, and T. basedowii occurs only in the interdunes. It was hypothesised that the deep sandy dunes afford greater water availability but lower nutrient supply to plants in this habitat compared with those occurring in the lower landscape position of the interdunes. Water-relations parameters (leaf water potentials, stomatal conductance, d13C) revealed that dune plants, particularly woody species, displayed higher water status and water use than closely related and often congeneric plants in the interdunes. Nutrient concentrations in soils were significantly higher in the interdunes, but concentrations in foliage were similar for related species between habitats. It is concluded that the dunes provide a greater store of accessible water than the soil profile in the interdunes. ... Following an experimental wetting pulse equivalent to a summer cyclone event, A. ancistrocarpa plants displayed significant increases in stomatal conductance, leaf water potential and sap velocity in lateral roots within three days of irrigation at the natural site and two days at the rehabilitation site. Secondary sinker roots originating from distal sections of lateral roots were evidently supplying water to maintain hydraulic function in laterals, thus enabling a fast pulse response. This was accentuated at the rehabilitation site where roots were confined closer to the surface. These results indicate that plants at the rehabilitation site are more dependent on small pulses of water and have less access to deep reserves than plants at the natural site. It is concluded that high runoff losses and insufficient soil depth are major factors contributing to plant water stress, and combined with the direct impacts of erosion, are largely responsible for plant death and ultimately poor plant cover. These issues can be alleviated if cover soil depth is increased to more than 0.5 m and slope angles are reduced to <12o. This study demonstrates the value of an ecophysiological approach for diagnosing problems affecting plant establishment at mine-rehabilitation sites. Furthermore, it has provided recommendations that will improve the rehabilitation strategy and lead to the development of a well vegetated, resilient ecosystem on a stable and non-polluting land form.
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Guo, Jing. "Téléopération sans fil reflétant la force pour la chirurgie robot-assistée." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT332/document.
Full textAbstract:
La robotique a fait progresser les interventions chirurgicales, avec des interventions moins invasives, une manipulation d’instruments plus précise et une meilleure dextérité. Néanmoins, le manque de retour haptique sur les plates-formes chirurgicales existantes aujourd’hui rend délicat l’accomplissement des gestes chirurgicaux et par conséquent augmente le risque de ces procédures. Avec l’introduction d’un retour haptique, les robots chirurgicaux sont conçus avec une approche de télé-opération bilatérale. Le retard, inhérent à cette approche, est crucial car même un petit retard pourrait déstabiliser le système. En pratique, le retard est inévitable, notamment pour les robots miniaturisés avec communication sans fils. Pour résoudre les problèmes liés à l’instabilité induite par le retard et rendre passif le canal de communication, l’approche de wave variable transformation (WVT) a été proposée. Néanmoins, les performances de suivi sont compromises à cause de la conservation de la condition de passivité. Dans cette thèse, une nouvelle approche de compensation basée sur la structure de wave variable, et considérant moins de condition de conservation est proposée afin d’améliorer les performances de suivi en position, en vitesse et en force. Pour garantir la passivité du système global, une approche énergétique (energy reservoir based regulators) est développée pour ajuster les termes de WVT avec une analyse rigoureuse. La méthode proposée permet d’améliorer les performances de suivi avec uniquement un retard de transmission dans un seul sens. Pour faciliter davantage les procédures chirurgicales, notamment les microchirurgies, deux facteurs d’échelle ont été rajoutés à l’approche de compensation. Une analyse de passivité a été par ailleurs menée en considérant la transparence du système. Les performances de suivi peuvent être obtenues si et seulement si les conditions de passivité et de transparence sont satisfaites. Les approches de compensation, avec et sans mise à l’échelle, ont été vérifiées à travers des simulations et des évaluations expérimentalesRobotic technology has advanced the surgical procedures in terms of reduced trauma, more accurate manipulation and enhanced dexterity. However, the lack of haptic feedback on existing surgical robotic platforms makes it impossible for the surgeon to feel the operative site,and thus increases the risks of surgical procedures. With the introduction of haptic feedback, the surgical robots are design in bilateral teleoperation way. Time delay in bilateral teleoperation is crucial because even small time delay may destabilize the system. In practice, time delay is unavoidable, e.g. wireless communication miniaturized surgical robots, internet based robotic-assisted telesurgery and transmission of big amount of information, etc. In order to solve the instability caused by time delay in bilateral teleoperation, wave variable transformation (WVT) method has been proposed to passivate the delayed communication channel. However, the tracking performances are compromised due to the conservative passivity condition. In this thesis, a new wave variable compensation (WVC) structure with less conservative condition is proposed to enhance the velocity/position and force tracking performances. In order to guarantee the passivity of the whole system, energy reservoir based regulators are designed to adjust the WVC terms in the proposed structure with rigorous analysis. The WVC is able to achieve tracking performance with only single trip time delay. To better facilitate the surgical procedures, e.g. the microsurgeries, a scaled WVC structure is also developed by adding two scaling factors to the WVC structure. Passivity analysis on the scaled WVC is conducted with consideration of system transparency. Scaled tracking performance can be obtained as long as the two obtained passivity and transparency conditions are satisfied. The proposed WVC and scaled WVC have been verified through simulation and experimental studies
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Dye, Jeremiah M. "An evaluation of two strains of Cyrtobagous salviniae Calder and Sands as natural enemies of the aquatic weeds salvinia molesta Mitchell and Salvinia minima Baker." Texas A&M University, 2005. http://hdl.handle.net/1969.1/3331.
Full textAbstract:
The floating aquatic weeds common salvinia (Salvinia minima Baker) and giant
salvinia (Salvinia molesta Mitchell) degrade aquatic systems through fast, mat forming
growth. The Salvinia specialist weevil Cyrtobagous salviniae Calder and Sands has
been used to reduce the severity of giant salvinia infestations and associated with
reduced severity of common salvinia infestations. Genetically, morphologically and
biologically distinct strains of C. salviniae exist, but their relative potential for success as
biological control agents of Salvinia species has not been evaluated. This thesis (1)
describes a recirculating water system designed for conducting such studies and (2)
reports the results of C. salviniae strain comparisons.
A recirculating water system with a high degree of replication and minimal
variation in water flow, temperature and light intensity was used for laboratory
experiments using sixty-day temperature profiles averaging 31.4, 26.5 and 8.0ºC
derived from surface water temperatures measured at lakes in expected range of Salvinia
species in the North America. Larval and adult population numbers of two C. salviniae strains (Australia and Florida) were determined for each temperature profile along with
feeding induced plant necrosis on both Salvinia species. Australia C. salviniae had
lower survivorship rates to adulthood on common salvinia than did Florida C. salviniae
at the 31.4 and 26.5ºC temperature profiles. Neither strain reproduced, and no
significant between-strain differences in plant necrosis were detected at the 8.0ºC
temperature profile. At 31.4ºC there were no significant differences in adult counts,
larval counts or plant damage between the two strains on giant salvinia. At 26.5ºC,
however, significantly fewer larvae were collected from initially released adults and
significantly less plant necrosis was associated with weevil feeding by Florida strain
compared to Australia strain weevils. These results may have arisen from comparing
Australia weevils from a growing colony to Florida weevils from a declining colony.
Overall, the results indicate that only Florida C. salviniae should be released against
common salvinia. Florida C. salviniae may be equally suitable to Australia C. salviniae
for releases against giant salvinia, but further study is needed to fully assess the potential
for using Florida C. salviniae against giant salvinia.
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Bristeau, Pierre-Jean. "Techniques d'estimation du déplacement d'un véhicule sans GPS et autres exemples de conception de systèmes de navigation MEMS." Phd thesis, École Nationale Supérieure des Mines de Paris, 2011. http://pastel.archives-ouvertes.fr/pastel-00755348.
Full textAbstract:
Dans cette thèse, on explique la conception et la mise au point d'un système de navigation sans GPS pour un véhicule automobile. Ce système exploite des mesures de champs magnétiques réalisées à bord du véhicule en mouvement, combinées à des mesures inertielles réalisées à partir de capteurs MEMS bas coût. Il permet de reconstituer, à partir d'une condition initiale, la trajectoire du véhicule en temps réel. Un prototype fonctionnel complet est présenté ainsi que des résultats expérimentaux. La conception de ce système repose sur une analyse de l'observabilité d'un modèle classique du véhicule, qui permet d'établir comment les différents biais et défauts des capteurs peuvent être estimés grâce à des filtres de Kalman agencés suivant deux schémas d'interconnexion: par partition des variables d'états et par séquencement. Une analyse de convergence des schémas d'estimation est étudiée. En dernière partie du manuscrit, deux autres exemples de systèmes de navigation à base de capteurs MEMS sont décrits, celui du quadricoptère Parrot AR.Drone et celui de fusées expérimentales à propulsion hybride, pour lesquels les mêmes principes de conception sont appliqués.