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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

A representação da cidade de São Paulo nos albores do século XX: os mapas como operadores na construção da cidade espraiada / The representation of the São Paulo city at the dawn of the twentieth century: the maps as operators in the construction of the sprawling city

Kuvasney, Eliane 18 December 2017 (has links)
O presente trabalho trata da cartografia produzida sobre a cidade de São Paulo entre 1877 e 1930 e de como essa cartografia interferiu na forma como a cidade foi vista e construída no período. Partimos da configuração do urbano metropolitano e de sua extensão, de forma que as questões que nortearam a pesquisa giravam em torno da lógica do espraiamento da cidade. A cidade foi pensada para ter essa característica ou foi sendo construída ao sabor do mercado imobiliário? Esse espraiamento é consequência das desigualdades sócio-espaciais ou é uma de suas causas? E, por fim, se os mapas interferiram na produção da cidade espraiada. Através de abordagem geohistórica e da metodologia de análise de mapas da Nova História da Cartografia, que constitui na desconstrução dos objetos cartográficos por meio da compreensão do contexto em que foram elaborados, desenvolveu-se a tese. Por isso, a primeira parte do trabalho é a contextualização do período na bibliografia existente, além das análises das atas e anais da Câmara Municipal de São Paulo, e dos relatórios de intendentes e prefeitos, visando compreender o período e a forma como o patrimônio municipal as terras pertencentes à municipalidade foi sendo apropriado pelo mercado imobiliário na construção da cidade, ao mesmo tempo em que não se obedecia o código de posturas que, desde 1875 exigia que o município fosse mapeado. Com o objetivo de analisar se os mapas teriam capacidade de agir com desempenho no espaço geográfico, se os mesmos atuaram como operadores na construção da cidade espraiada, optou-se também por análises desdobradas da semiose cartográfica para uma melhor compreensão dos fenômenos da autorreferencia e da iconização. A partir da análise de três séries de mapas da cidade foi possível, através da desconstrução e da ressiginificação dos mapas em suas séries, e da análise de seus aspectos autorreferenciais, chegar à gênese da imagem do espraiamento da cidade a partir da planta de 1897 e seus desdobramentos. / The present work deals with the cartography produced about the city of São Paulo between 1877 and 1930 and how this cartography interfered in the way the city was seen and constructed in the period. We begin from the configuration of the metropolitan urban and its extension, so that the questions which guided the research revolved around the citys sprawlings logic. The city was designed for such structure or was it a product of the real estate market? Is this spreading due to socio-spatial inequalities or is it one of its causes? And, finally, if the maps interfered in the production of the sprawled city. Through a geo-historical approach and methodology of New History of Cartography map analysis, which constitutes in the deconstruction of cartographic objects through the understanding of the context in which they were elaborated, the thesis was developed. Therefore, the first part of the work is the contextualization of the period through existing bibliography, in addition to the analysis of the São Paulo City Halls minutes and annals, and the main deputies and mayors reports, aiming the comprehension of the period and the way in which the municipal patrimony - as lands belonging to the municipality - was being appropriated by the real estate market in the citys construction, while obeying the code of posture that, since 1875, required that the municipality was mapped. With the objective of analyzing whether the maps would have performance capability in the geographic space, that is, if they acted as operators in the construction of the sprawled city, we also opted for unfolded analyzes of cartographic semiosis for a better understanding of the phenomena of self-reference and iconization. From the analysis of the three series of the citys maps it was possible, through the deconstruction and resignification of the map in its series, and the analysis of its self-referential aspects, to arrive at the genesis of the image of the city\'s sprawling - from the 1897 plant - and its unfolding.
242

Tomography of the Earth by Geo-Neutrino Emission / Tomografia da Terra pela emissão de geo-neutrinos

Tavares, Leonardo Estêvão Schendes 05 August 2014 (has links)
Geo-neutrinos are electronic anti-neutrinos originated from the beta decay process of some few elements in the decay chains of $^Th$ and $^U$ present in Earth\'s interior. Recent experimental measurements of these particles have been generating great expectations towards a new way for investigating directly the interior of the planet. It is a new multidisciplinary area, which might in the near future bring considerable clues about Earth\'s thermal dynamics and formation processes. In this work, we construct an inferential model based on the multigrid priors method to deal, in a generic way, with the geo-neutrino source reconstruction problem. It is an inverse problem; given a region in space V and a finite and small number of measurements of the potential generated on the surface of V by some charge distribution $ho$, we try to infer $ho$. We present examples of applications and analysis of models in two and three dimensions and we also comment how other a priori information may be included. Furthermore, we indicate the steps for inferring the best locations for future detectors. The objective is to maximize the amount of information liable to be obtained from experimental measurements. We resort to an entropic method of inference which may be applied right after the results of the multigrid method are obtained. / Geo-neutrinos são neutrinos provindos do decaimento beta de alguns poucos elementos nas cadeias de $^$Th e $^$U presentes no interior da Terra. Recentes medidas experimentais dessas partículas têm proporcionado grandes expectativas como uma nova maneira de se investigar o interior do planeta diretamente. Trata-se de uma área multidisciplinar nova, que poderá no futuro próximo nos trazer grandes esclarecimentos sobre a dinâmica térmica e o processo de formação da Terra. Neste trabalho, construímos um modelo de inferência baseado no método de multigrid de priors para tratar, de modo genérico, o problema da reconstrução das fontes de geo-neutrinos no interior da Terra. Trata-se de um problema inverso; dada uma região do espaço V e um número finito e pequeno de medidas do potencial gerado na superfície de V por uma distribuição de carga $ho$, tentamos inferir $ho$. Apresentamos exemplos de aplicações e análises do método em modelos bidimensionais e tridimensionais e também comentamos como outras informações a priori podem ser incorporadas. Além disso, indicamos os passos para se inferir onde detectores futuros devem ser posicionados. O objetivo é maximizar a informação passível de ser obtida das medidas experimentais. Utilizamos um método baseado em inferência entrópica e que pode ser aplicado diretamente depois que os resultados do método de multigrid são obtidos.
243

Towards Unifying Stream Processing over Central and Near-the-Edge Data Centers

Peiro Sajjad, Hooman January 2016 (has links)
In this thesis, our goal is to enable and achieve effective and efficient real-time stream processing in a geo-distributed infrastructure, by combining the power of central data centers and micro data centers. Our research focus is to address the challenges of distributing the stream processing applications and placing them closer to data sources and sinks. We enable applications to run in a geo-distributed setting and provide solutions for the network-aware placement of distributed stream processing applications across geo-distributed infrastructures.  First, we evaluate Apache Storm, a widely used open-source distributed stream processing system, in the community network Cloud, as an example of a geo-distributed infrastructure. Our evaluation exposes new requirements for stream processing systems to function in a geo-distributed infrastructure. Second, we propose a solution to facilitate the optimal placement of the stream processing components on geo-distributed infrastructures. We present a novel method for partitioning a geo-distributed infrastructure into a set of computing clusters, each called a micro data center. According to our results, we can increase the minimum available bandwidth in the network and likewise, reduce the average latency to less than 50%. Next, we propose a parallel and distributed graph partitioner, called HoVerCut, for fast partitioning of streaming graphs. Since a lot of data can be presented in the form of graph, graph partitioning can be used to assign the graph elements to different data centers to provide data locality for efficient processing. Last, we provide an approach, called SpanEdge that enables stream processing systems to work on a geo-distributed infrastructure. SpenEdge unifies stream processing over the central and near-the-edge data centers (micro data centers). As a proof of concept, we implement SpanEdge by extending Apache Storm that enables it to run across multiple data centers. / <p>QC 20161005</p>
244

Vision-Based Localization and Guidance for Unmanned Aerial Vehicles

Conte, Gianpaolo January 2009 (has links)
The thesis has been developed as part of the requirements for a PhD degree at the Artificial Intelligence and Integrated Computer System division (AIICS) in the Department of Computer and Information Sciences at Linköping University.The work focuses on issues related to Unmanned Aerial Vehicle (UAV) navigation, in particular in the areas of guidance and vision-based autonomous flight in situations of short and long term GPS outage.The thesis is divided into two parts. The first part presents a helicopter simulator and a path following control mode developed and implemented on an experimental helicopter platform. The second part presents an approach to the problem of vision-based state estimation for autonomous aerial platforms which makes use of geo-referenced images for localization purposes. The problem of vision-based landing is also addressed with emphasis on fusion between inertial sensors and video camera using an artificial landing pad as reference pattern. In the last chapter, a solution to a vision-based ground object geo-location problem using a fixed-wing micro aerial vehicle platform is presented.The helicopter guidance and vision-based navigation methods developed in the thesis have been implemented and tested in real flight-tests using a Yamaha Rmax helicopter. Extensive experimental flight-test results are presented. / WITAS
245

Geo-Visualization Tools for Participatory Urban Planning - The Case of Tripoli, Lebanon

El Nabbout, Khaled 08 June 2007 (has links) (PDF)
Geo-data visualization has always been an important tool in the urban planning process. Recent trends in geo-information technology are, however, offering additional opportunities for the development of new visualization tools. In parallel, developments have also taken place in the field of urban planning, which has evolved from the rational planning model towards a more strategic planning process with a greater emphasis on collaboration and inclusiveness. This study investigates how an innovative geo-data visualisation tool can be used to develop more inclusive and participatory planning processes, and it tests this approach by means of a case study in Tripoli, Lebanon. The study compared two geo-data visualization techniques regarding their potential for an increased involvement of different types of stakeholders in the urban planning processes: The first technique employed coloured printed transparency maps of the present land-use and the 2000-2020 Master Plan, both geo-referenced to a mosaic of QuickBird satellite imagery used to assist the participant’s orientation. The second technique was the Lenticular Foil Display (LFD) using the so-called flip effect, also based on the geo-coding of the same three “layers”. By tilting this product the observer was easily able to interpret the changes between present and planned state. The LFD technology is particularly useful for true-3D (auto-stereoscopic) viewing. Statistical evaluations of questionnaires concerning sociological and perception-scientific aspects revealed interesting details regarding the role of the new visualization method in the participatory city planning process. The result of the interviews revealed that all stakeholders were readily able to participate in the planning process and to contribute their ideas by sketch-map drawing and writing, using the LFD technology. Regarding the possibilities to stimulate the participation of different stakeholders in the planning process, the LFD was found to be more effective than the conventional approach using transparencies overlaid over orthophotos. Non-experts, in particular, preferred the LFD technology to the transparent overlays which were, however, the preferred approach for the professionals and experts familiar with Master Plan map-reading. One conclusion of the present study is that an efficient participatory urban-planning process should explicitly consider the level of map-reading skills of the stakeholders. Geo-data visualization products like the Multi-Flip-LFDs and other innovative approaches offer possibilities to improve stakeholder participation. The monograph closes by making concrete suggestions for further research into the development and optimization of LFDs.
246

Σχεδιασμός και υλοποίηση προηγμένων μαθηματικών μεθόδων για την επίλυση προβλημάτων πολλαπλών πεδίων σε σύγχρονες υπολογιστικές αρχιτεκτονικές

Κορφιάτη, Αίγλη 05 February 2015 (has links)
Για την επίλυση προβλημάτων πολλαπλών πεδίων / πολλαπλών φυσικών έχουν προταθεί διάφορες τεχνικές στη βιβλιογραφία. Οι μέθοδοι χαλάρωσης στις διεπαφές είναι μια ενδιαφέρουσα προσέγγιση για την επίλυση αυτών των προβλημάτων. Υποθέτοντας κάποιες αρχικές τιμές στις διεπαφές του προβλήματος, οι μέθοδοι χαλάρωσης στις διεπαφές επιλύουν επαναληπτικά τα υποπροβλήματα και χαλαρώνουν τις τιμές στις διεπαφές έως ότου επιτευχθεί σύγκλιση. Τα κυριότερα πλεονεκτήματα των μεθόδων αυτών είναι ότι οι ρυθμοί σύγκλισής τους εξαρτώνται μόνο από τις παραμέτρους των ίδιων των προβλημάτων, τις παραμέτρους που σχετίζονται με την ανάλυση των προβλημάτων σε υποπροβλήματα και τις παραμέτρους που σχετίζονται με τον τελεστή που εφαρμόζεται στις διεπαφές. Στην παρούσα μεταπτυχιακή εργασία παρουσιάζεται μια νέα υλοποίηση μιας μεθόδου χαλάρωσης στις διεπαφές, της μεθόδου GEO. Η GEO βασίζεται σε έναν απλό μηχανισμό γεωμετρικής διόρθωσης και δρα επαναληπτικά, ώστε να χαλαρώσει τις τιμές στις διεπαφές. Πιο συγκεκριμένα, προσθέτει στις παλιές τιμές των διεπαφών έναν γεωμετρικά σταθμισμένο συνδυασμό των κανονικών παραγώγων των οριακών σημείων των γειτονικών πεδίων. Η υλοποίηση της μεθόδου GEO γίνεται στην πλατφόρμα FEniCS, η οποία είναι μια συλλογή ελεύθερου λογισμικού για την αυτοματοποιημένη, αποδοτική υλοποίηση διαφορικών εξισώσεων. Η υλοποίηση πραγματοποιείται με τρόπο τέτοιο που ο χρήστης να μπορεί εύκολα να ορίζει τις ιδιότητες των πεδίων του προβλήματος (όπως, γεωμετρία του προβλήματος, τελεστής μερικής διαφορικής εξίσωσης, οριακές συνθήκες, συνθήκες διεπαφών). Στο παρασκήνιο γίνεται η δημιουργία ή / και η βελτιστοποίηση των πλεγμάτων (τριγωνικά στοιχεία) για κάθε πεδίο του προβλήματος, η επίλυση των τοπικών προβλημάτων μερικών διαφορικών εξισώσεων και η εμφάνιση των υπολογισμένων τιμών για το πρόβλημα συνολικά και για τις διεπαφές. Η κυριότερη πρόκληση της υλοποίησης είναι η πρόσβαση στις τιμές των λύσεων στις διεπαφές και η εισαγωγή των χαλαρωμένων τιμών πίσω στα υποπροβλήματα για να αποτελέσουν τις οριακές συνθήκες των υποπροβλημάτων. Πραγματοποιούνται πειράματα σε προβλήματα-μοντέλα, ώστε να ελεγχθεί η εφαρμοσιμότητα και η σύγκλιση της μεθόδου. Στη συνέχεια, υλοποιείται μια παράλληλη έκδοση της μεθόδου και πραγματοποιούνται συγκριτικά πειράματα απόδοσης. Η παράλληλη υλοποίησή μας αποδεικνύεται πολύ χρήσιμη, ειδικά για μεγάλα προβλήματα. / Several approaches have been suggested in the literature for the solution of multiphysics / multidomain problems. Interface Relaxation (IR) methods are an interesting approach for the solution of these problems. Assuming initial guesses on the interfaces of the original problem, IR methods iteratively solve the subproblems and relax for new values on the interfaces until convergence is succeeded. Their main advantages are that their rates of convergence only depend on the parameters of the problem itself, the parameters related to its decomposition into subproblems and the parameters related to the operator imposed on the interfaces. In the present master thesis a new implementation of an IR method named GEO is presented. GEO is based on a simple geometric correction mechanism and acts iteratively so as to relax the values of the solution on the interfaces. In particular, it adds to the old interface values a geometrically weighted combination of the normal boundary derivatives of the adjacent subdomains. In this thesis GEO is implemented in FEniCS. The FEniCS project is a collection of free software for automated, efficient solution of differential equations. In order to evaluate the GEO implementation, it is applied on two different PDE problems with the same differential equation and boundary conditions and different domains. FEniCS methods are used to specify the problem's subdomains properties (i.e. geometry, PDE operator and boundary/interface conditions). They are also used to generate and/or refine meshes (triangular elements) for each subdomain, solve the local PDE problems and show the computed results in the global domain and on the interfaces. Getting values of the solutions on the interface (boundaries of the subproblems) and passing the new relaxed values back to the subproblems as updated values for the boundary conditions is the main challenge of the IR methodology implementation. Experiments are performed for 2-dimensional elliptic partial differential model problems with partitions in multiple subdomains and the results are examined in terms of the method's applicability and convergence. A parallel implementation of the GEO method using FEniCS is also presented, as well as its performance comparison to the serial implementation. The parallel implementation proves to be really useful, especially for large problems.
247

Geografická gramotnost laické veřejnosti / Geographical literacy of general public

Wackershauserová, Marie January 2018 (has links)
This thesis focuses on geographical literacy of the general public. It sets two main aims. Firstly to identify geographical community opinion on what knowledge and skills should be these days considered basics of geographical literacy for everyone regardless of their age and achieved education. Secondly to verify the selected basics of geographical literacy with the lay public. The structure of this work follows these aims. The theoretical part concentrates on the explanation of key words and the definition of geographical literacy in accordance with contemporary literature. The other part of the work presents the results of two researches of one's own. The first one was done in the form of an electronic questionnaire and addressed to the members of the geographical community. They firstly used a four-level scale to consider the importance of knowledge and skills that were verified in the research of the geographical literacy of adults in the USA. Secondly, in the form of open-answer questions, they could express their opinion on the core of the monitored assessment reference scope. It proved that assessment statements to most suggested skills are very varying. On the grounds of the evaluation of this survey we suggested requirements for individual performances that apply to closely defined issues,...
248

Proposta de zoneamento geoambiental do munic?pio do Crato/CE

Lima, Fl?via Jorge de 28 October 2008 (has links)
Made available in DSpace on 2015-03-13T17:10:30Z (GMT). No. of bitstreams: 1 FlaviaJL.pdf: 4348490 bytes, checksum: 9833ad5ebc75cab0e9063c256b3ba90c (MD5) Previous issue date: 2008-10-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The geo-environmental zoning is an important means to plan the management of the territory, once it is the result of integration of different elements of the physical environment. The Municipality of Crato has a diversity of geo-environmental systems due to its complex landscape, which characterization and delimitation will contribute to the most appropriate occupation and the fewer prejudicial to municipal area. This study, which was supported by geo-systemic theory, searched to reach the following objectives: to elaborate a proposal of geo-environmental zoning; to characterize identified and demarcated geo-environmental systems, including their potentiality and limitations of land use and human occupation; and to generate a database on digital maps through GIS Geographic Information System. Four geo-environmental systems were identified (Chapada do Araripe: plateau and hillside, Massif and residual crest, Sert?o of peripheric southern depression and fluvial Plains) and ten geo-environmental subsystems (Eastern plateau covered by cerrad?o/cerrado, Western plateau covered by cerrado/carrasco, Northern-west hillside, central residual Massif, Northern Residual Massifs, Sertaneja depression dominated by sedimentary materials, Sertaneja depression dominated by embasement crystalline material; wet fluvial plains and dry fluvial plains). The identified system and subsystem are similar to those proposed by FUNCEME in spite of some changes due to the more detailed mapping / O zoneamento geoambiental, como produto da integra??o dos diferentes elementos do meio f?sico, ? um importante instrumento para o planejamento da gest?o do territ?rio. O munic?pio do Crato, em fun??o de sua complexa paisagem, apresenta uma diversidade de sistemas geoambientais, cuja caracteriza??o e delimita??o poder?o contribuir para a ocupa??o mais adequada e menos impactante do espa?o municipal. Esse trabalho, apoiado na teoria geossist?mica, buscou atingir os seguintes objetivos: elaborar uma proposta de zoneamento geoambiental; caracterizar os sistemas geoambientais identificados e delimitados, envolvendo suas potencialidades e limita??es em termos de uso e ocupa??o do solo; e gerar uma base de dados com mapas digitais em ambiente SIG (Sistema de Informa??o Geogr?fica). Foram identificados quatro sistemas geoambientais (Chapada do Araripe: Plat? e Encostas, Maci?os e Cristas Residuais, Sert?es da Depress?o Perif?rica Meridional do Cear? e Plan?cies Fluviais) e dez subsistemas geoambientais (Plat? Oriental Revestido por Cerrad?o/Cerrado, Plat? Ocidental Revestido por Cerrado/Carrasco, Encosta Norte-Ocidental, Encosta Oriental, Maci?o Residual Central, Maci?os Residuais Setentrionais, Depress?o Sertaneja Dominada por Material Sedimentar, Depress?o Sertaneja Dominada por Material do Embasamento Cristalino, Plan?cies Fluviais ?midas e Plan?cies Fluviais Secas). Os sistemas e subsistemas identificados seguem, em parte, aqueles propostos pela FUNCEME, com mudan?as em fun??o do maior detalhe do mapeamento proposto
249

Tomography of the Earth by Geo-Neutrino Emission / Tomografia da Terra pela emissão de geo-neutrinos

Leonardo Estêvão Schendes Tavares 05 August 2014 (has links)
Geo-neutrinos are electronic anti-neutrinos originated from the beta decay process of some few elements in the decay chains of $^Th$ and $^U$ present in Earth\'s interior. Recent experimental measurements of these particles have been generating great expectations towards a new way for investigating directly the interior of the planet. It is a new multidisciplinary area, which might in the near future bring considerable clues about Earth\'s thermal dynamics and formation processes. In this work, we construct an inferential model based on the multigrid priors method to deal, in a generic way, with the geo-neutrino source reconstruction problem. It is an inverse problem; given a region in space V and a finite and small number of measurements of the potential generated on the surface of V by some charge distribution $ho$, we try to infer $ho$. We present examples of applications and analysis of models in two and three dimensions and we also comment how other a priori information may be included. Furthermore, we indicate the steps for inferring the best locations for future detectors. The objective is to maximize the amount of information liable to be obtained from experimental measurements. We resort to an entropic method of inference which may be applied right after the results of the multigrid method are obtained. / Geo-neutrinos são neutrinos provindos do decaimento beta de alguns poucos elementos nas cadeias de $^$Th e $^$U presentes no interior da Terra. Recentes medidas experimentais dessas partículas têm proporcionado grandes expectativas como uma nova maneira de se investigar o interior do planeta diretamente. Trata-se de uma área multidisciplinar nova, que poderá no futuro próximo nos trazer grandes esclarecimentos sobre a dinâmica térmica e o processo de formação da Terra. Neste trabalho, construímos um modelo de inferência baseado no método de multigrid de priors para tratar, de modo genérico, o problema da reconstrução das fontes de geo-neutrinos no interior da Terra. Trata-se de um problema inverso; dada uma região do espaço V e um número finito e pequeno de medidas do potencial gerado na superfície de V por uma distribuição de carga $ho$, tentamos inferir $ho$. Apresentamos exemplos de aplicações e análises do método em modelos bidimensionais e tridimensionais e também comentamos como outras informações a priori podem ser incorporadas. Além disso, indicamos os passos para se inferir onde detectores futuros devem ser posicionados. O objetivo é maximizar a informação passível de ser obtida das medidas experimentais. Utilizamos um método baseado em inferência entrópica e que pode ser aplicado diretamente depois que os resultados do método de multigrid são obtidos.
250

Os valores de referência, assinatura isotópica de fatores de enriquecimento de metais Pb e pesados em solos que cercam uma baía do ambiente impactado no Brasil. / Reference values, isotopic signature of Pb and heavy metal enrichment factors in soils surrounding an environmentally-impacted bay in Brazil

SANTOS, Nielson Machado dos 06 July 2015 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2016-08-17T12:29:29Z No. of bitstreams: 1 Nielson Machado dos Santos.pdf: 2159134 bytes, checksum: 0924bbce3bea148e3c14b840a9443026 (MD5) / Made available in DSpace on 2016-08-17T12:29:29Z (GMT). No. of bitstreams: 1 Nielson Machado dos Santos.pdf: 2159134 bytes, checksum: 0924bbce3bea148e3c14b840a9443026 (MD5) Previous issue date: 2015-07-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work was carried out to investigate the possible influence of human activities on heavy metal concentrations, by enrichment factor and isotopic signature of Pb and determine the natural levels of heavy metals in the vicinity Todos os Santos Bay-BA (BTS). For this, two sampling design of the soil around the BTS were realized. The first sampling 114 topsoil samples (0.0 - 0.2 m depth) were collected from 38 samplings sites and the concentrations of Pb, Zn, As, Cd, and Hg were determined by ICP-OES or AA-FIAS after microwave sample digestion. Results showed that mean values for heavy metal concentrations in soils (mg kg-1) followed the order Pb (39.45) > Zn (12.52) > As (1.95) > Cd (0.23) > Hg (0.09). The mean natural concentrations of heavy metals found in the soils of an important economic region of Brazil’s were generally lower than those reported in the national and international literature, with exception Pb concentration that was higher than all compared soils.The quality reference values (QRvs) calculated for the TSB based on the 75th percentile, were as follows (mg kg−1): Pb (54.37); Cr (36.55); Zn (10.40); Cu (7.10); Ni (4.05); Co (0.38); Cd (0.30). The second sampling six soil profiles were collected, the samples were collected from different horizons, totaling 44 samples. Soil pits were dug until 2 m or until the parent material (C horizon) was reached.The soil samples were microwave digested in the mixture of HNO3, H2O2 using the method described by Sah and Miller (1992). Concentrations of Pb and the isotopes 204Pb, 206Pb, 207Pb and 208Pb were measured on an inductively coupled plasma (quadrupole) mass spectrometry. Pb concentrations varied from 3.2 to 44.1 mg kg−1 with an average concentration of 13.65 mg kg−1. In general the samples feature a wide range of Pb isotope ratios, ranging from 36.71 to 47.38 for 208Pb/204Pb, 16.86 to 20.59 for 206Pb/204Pb, 1.10 to 1.31 for 206Pb/207Pb and a ranged slightly from 15.00 to 15.65 for 207Pb/204Pb. The PCA performed identified that Pb, Zn, and Cd were associated with the same factor (F1) and had chiefly anthropogenic origin whereas Pb and Zn have also contributions from both sources (natural, lithogenic and anthropogenic). The As and Hg concentrations (F2) were related to the natural component; the parent material underlying the soils (igneous-metamorphic rocks) seemingly confirm this hypothesis. The natural concentrations of heavy metals in soils of TSB had the following decreasing order: Pb > Cr > Zn > Cu > Ni > Co > Cd. Pb concentration in all soil profiles not seem have been influenced by the abandoned lead smelter plant located in the municipality of Santo Amaro da Purificação-BA. The distinct Pb isotopic compositions were clearly related to the different exposure of the sampling sites in relation to atmospheric deposition and geological parent material. / Este trabalho foi realizado para investigar a possível influência das atividades humanas sobre as concentrações de metais pesados, por fator de enriquecimento e assinatura isotópica de Pb e determinar os níveis naturais de metais pesados ​​nas imediações Todos os Santos Bay-BA (BTS). Para isso, duas projecto de amostragem do solo ao redor da BTS foram realizados. A primeira amostragem de 114 amostras de solo superficial (0,0-0,2 m de profundidade) foram coletadas de 38 amostragens sites e as concentrações de Pb, Zn, As, Cd, Hg e foram determinados por ICP-OES ou AA-FIAS após digestão de amostras de microondas. Os resultados mostraram que os valores médios para as concentrações de metais pesados ​​em solos (mg kg-1) seguido a ordem Pb (39,45)> Zn (12,52)> Como (1,95)> Cd (0,23)> Hg (0,09). As concentrações médias naturais de metais pesados ​​encontrados nos solos de uma importante região econômica do Brasil de foram em geral menores que os relatados na literatura nacional e internacional, com exceção Pb concentração que era maior do que todos em comparação soils.The valores de referência de qualidade (QRvs) calculada para TSB a partir do percentil 75, foram as seguintes (mg kg-1): Pb (54,37); Cr (36,55); Zn (10,40); Cu (7,10); Ni (4,05); Co (0,38); Cd (0,30). A segunda amostragem seis perfis de solo foram coletadas, as amostras foram coletadas de horizontes diferentes, totalizando 44 amostras. Poços de solo foram escavadas até 2 m ou até que o material de origem (C horizonte) foi amostras de solo foram reached.The microondas digerido na mistura de HNO3, H2O2, utilizando o método descrito por Sah e Miller (1992). As concentrações de Pb e os isótopos 204Pb, 206Pb, 207Pb e 208Pb foram medidos em uma espectrometria de massa com plasma indutivamente acoplado (quadrupolo). Concentrações de Pb variou de 3.2 para 44,1 mg kg-1 com uma concentração média de 13,65 mg kg-1. Em geral, as amostras apresentam uma vasta gama de relações isotópicas Pb, variando 36,71-47,38 para 208Pb / 204Pb, 16,86-20,59 para 206Pb / 204Pb, 1,10-1,31 para 206Pb / 207Pb e uma variou ligeiramente 15,00-15,65 para 207Pb / 204Pb . O PCA realizada identificou que Pb, Zn e Cd foram associados com o mesmo fator (F1) e teve origem principalmente antropogénica Considerando Pb e Zn também tem contribuições de ambas as fontes (naturais, litogênicos e antropogênicos). As concentrações de Hg e Como (F2) estavam relacionados com a componente natural; o material de origem subjacentes aos solos (ígnea-rochas metamórficas) aparentemente confirmar esta hipótese. As concentrações naturais de metais pesados ​​em solos de TSB teve a seguinte ordem decrescente: Pb> Cr> Zn> Cu> Ni> Co> Cd. Concentração de Pb em todos os perfis de solo não parecem ter sido influenciados pela planta fundição de chumbo abandonada localizada no município de Santo Amaro da Purificação-BA. As composições isotópicas de Pb distintas foram claramente relacionadas com a diferente exposição dos pontos de amostragem em relação à deposição atmosférica e material de origem geológica.

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