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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.
71

Wachstumspotentiale erneuerbarer Energien und ihre Implikationen für Klimaschutz, Versorgungssicherheit und Wettbewerbsfähigkeit /

Herholz, Ute. January 2006 (has links) (PDF)
Univ., Diss.--Hamburg, 2005. / Zsfassung in dt. Sprache.
72

População e riscos as mudanças ambientais em zonas costeiras da Baixada Santista = um estudo socio-demografico sobre os municipios de Bertioga, Guaruja e São Vicente / Population and risks to environmental changes in Baixada Santista coastal zoner : a socio-demographic study on the municipalities of Bertioga, Guaruja and São Vicente

Silva, César Augusto Marques da, 1985- 15 August 2018 (has links)
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciencias Humanas / Made available in DSpace on 2018-08-15T21:24:43Z (GMT). No. of bitstreams: 1 Silva_CesarAugustoMarquesda_M.pdf: 4288587 bytes, checksum: 7047af8acde22f0055c700f95c46522f (MD5) Previous issue date: 2010 / Resumo: Durante as últimas décadas a demografia discutiu importantes conceitos ao tratar da relação entre dinâmica populacional e mudança ambiental. Surgiram novos caminhos, buscando compreender essa relação em análises centradas no entendimento do papel do espaço, dos padrões de produção e consumo, do risco e da vulnerabilidade. Recentemente, com a confirmação das estimativas das mudanças climáticas, a demografia é novamente desafiada a elucidar os elementos da dinâmica populacional que afetam o clima e que por ela são afetados. Nessa pesquisa objetiva-se compreender elementos desse segundo ponto, analisando riscos ambientais às mudanças climáticas em populações residentes em zonas costeiras. Mais especificamente, analisamos a dinâmica de três municípios costeiros do Estado de São Paulo, na Região Metropolitana da Baixada Santista: Bertioga, Guarujá e São Vicente. Tais municípios, majoritariamente urbanos, abrigam espaços diferenciados e desiguais, tanto do ponto de vista geográfico como social. Geograficamente, a presença de morros, rios, estuários e do próprio mar, condicionam a formação de riscos ambientais diferenciados. Socialmente, com a ocupação dos espaços para usos diversos (residenciais, turísticos e industriais), e por grupos com perfis sócio-econômicos particulares, cada um desses riscos atinge populações também específicas. A partir desses fatores a hipótese do trabalho é que populações com características distintas passam por diferentes riscos ambientais. Desse modo, os riscos que selecionamos são relativos às mudanças ambientais: a elevação do nível do mar, as inundações e os deslizamentos. Para cada um desses riscos, e de suas possíveis combinações, foram criadas zonas de risco, utilizando os dados de setores censitários. Os resultados indicaram a confirmação da nossa hipótese: populações mais pobres estão nas imediações de corpos d'água e morros, áreas onde a possibilidade das intensificações de inundações e deslizamentos é maior, enquanto as mais ricas localizam-se próximas ao mar, onde o maior risco é o da elevação do nível médio do mar / Abstract: Demography has discussed important concepts in concern with the relation between population dynamics and environmental change through last decades. New ways were developed and the role of space, patterns of production and consumption, risk and vulnerability were incorporated in theses analysis. Recently, with more accuracy estimates of climate change, demography is again challenged to elucidate the elements of population dynamics that affect climate and vice-versa. This research aims to understand this elements, analyzing risks of climate change on populations living in coastal areas. More specifically, we analyze the dynamics of three coastal municipalities of Sao Paulo State, in the Metropolitan Area of Baixada Santista: Bertioga, Guarujá and São Vicente. These municipalities, mostly urban, harbor differentiated and uneven spaces, both geographically and socially. Geographically, the presence of hills, rivers, estuaries and the sea, influence different environmental risks. Socially, space has been transformed according to several social uses (residential, tourist and industrial), resulting in specific groups, with particular socio-economic profiles, living in distinct risks zones. Based on these factors, the hypothesis adopted is that populations with different characteristics are replaced by different environmental risks. Therefore, the risks selected represent some of the environmental changes dangers: rising sea levels, more intensive flooding and landslides. For each of these risks, and their possible combinations were created risk areas, using data from census tracts. The results indicated the poorest are in the vicinity of ponds and hills, where the possibility of intensification of floods and landslides is higher, while the richest are sited near sea, where the greatest risk is the elevation of the average sea level / Mestrado / Demografia / Mestre em Demografia
73

Détermination des facteurs du sol modulant la biodisponibilité et l'accumulation des métaux pour l'escargot (cantareus aspersus) / Determination of soil parameters modulating the biovailability and the accumulation of metals to the snai (cantareus aspersus)

Pauget, Benjamin 12 July 2012 (has links)
[...] L’objectif decette thèse est l’étude des mécanismes modulant la biodisponibilité des métaux pour l’escargotCantareus aspersus (syn. Helix aspersa), invertébré vivant à l’interface sol‐plante‐air (maillonintermédiaire, saprophage, phytophage, de chaînes alimentaires). La biodisponibilité est principalementévaluée ici en mesurant l’accumulation (concentrations internes en métaux après 28 jours d’exposition) etles flux d’assimilation. L’influence de paramètres édaphiques sur la disponibilité et la biodisponibilité desmétaux des sols et la contribution des sources de contamination (sols/plantes) des escargots constituentles variables étudiées dans deux conditions d'exposition :[...] L’ensemble des résultats souligne la nécessité de prendre en compte les facteurs et lesmécanismes qui modulent la biodisponibilité des métaux pour modéliser au mieux leur accumulation etleur assimilation par les escargots. Aucune méthode chimique unique d’estimation de la biodisponibilitédes métaux n’ayant pu être déterminée, nous préconisons l’utilisation de mesures biologiques quireflètent mieux la réelle biodisponibilité. / [...] The aim of this thesis is to study the mechanisms that modulate metal bioavailabilityfor the garden snail Cantareus aspersus (= Helix aspersa) a soil invertebrate living at the interfacesoil‐plant‐air (saprophagous and phytophagous intermediate link in the food chain).[...] These data underline the necessity to take into account the factors and mechanisms that modulate themetal bioavailability for snails to better model accumulation and assimilation of metal by snails. As nounique chemical method to assess metal bioavailability was determined, we recommend the use ofbiological measures that identify the real metal bioavailability rather than the use of chemical measures.
74

Couplage d’approches expérimentales et modélisatrices pour l'étude des mécanismes d'effet de perturbateurs endocriniens chez la limnée des étangs, Lymnaea stagnalis. / Towards understanding the effects of putative endocrine disruptors in the great pond snail Lymnaea stagnalis : experimental and toxicokinetic-toxicodynamic modelling approaches

Barsi, Alpar 14 January 2015 (has links)
Les produits phytosanitaires contiennent des molécules qui peuvent interférer avec le système endocrinien et induire des effets délétères sur les êtres vivants. Ce sont des perturbateurs endocriniens. Afin d’assurer un niveau de protection satisfaisant pour les mollusques aquatiques, une bonne compréhension des perturbations du système endocrinien est nécessaire. L’organisation pour le développement et la coopération économique s’est exprimée en faveur de la mise en place de protocoles standards d’écotoxicité chez les mollusques, notamment sur la reproduction, dans le cadre des processus d’évaluation du risque écologique et des autorisations de mise sur le marché de nouvelles molécules. Cette thèse vise à proposer des tests standards et des outils d’analyse afin d’évaluer les effets de substances chimiques chez un escargot d’eau douce, Lymnaea stagnalis. Une série de tests de toxicité a été conduite dans laquelle les limnées ont été exposées à des androgènes, des oestrogènes et dessolvants. Les effets observés ont été évalués à l’aide d’approches statistiques standards et d’un modèle de toxicokinétique-toxicodynamique (TKTD). Les limnées ont montré une sensibilité uniquement au tributyltin et triphényltin à des concentrations réalistes d’un point de vue environnemental. Le triéthylène glycol et l’acétone étaient les solvants les moins nocifs. De plus, le modèle TKTD suggère un mécanisme généraliste dans l’action du composé. La manifestation des perturbations endocriniennes chez L. Stagnalis restent évasives et nécessitent d’autres recherches. Enfin, la thèse a montré que / Plant protection products and biocides may contain chemicals that interfere with the endocrine system and consequently induce adverse effects on wildlife. Such chemicals are known as endocrine disruptors (EDs). To ensure a satisfactory protection level for aquatic molluscs a comprehensive understanding of endocrine disruption is needed. The Organisation for Economic Co-operation and Development supports the standardisation of toxicity tests guideline on mollusc reproductive toxicity, which is intended for environmental risk assessments purposes. This PhD thesis aimed at improving toxicity test protocols and data analysis tools to evaluate effects of chemicals on the great pond snail Lymnaea stagnalis. A suite of toxicity tests was conducted in which snails were exposed to putative androgens (tributyltin, triphenyltin, methyltestosterone), putative oestrogens (alkylphenols and ethynyloestradiol), and solvents. Resulting effects were evaluated using standard statistical approachesand/or a toxicokinetic-toxicodynamic (TKTD) model. Snails were sensitive to tributyltin and triphenyltin, while none of the oestrogenic chemicals and methyltestosterone significantly impacted animals at environmentally relevant concentrations. Triethylene glycol and acetone were the least harmful solvents. Further, the analysis of data from the tributyltin test with the TKTD model suggested a generic mechanism of action of the compound (i.e., not specific for EDs). The demonstration of endocrine disruption in L. stagnalis remained elusive and deserves further research. Finally, the thesis highlight
75

Governando as mudanças climáticas no nível local : riscos e respostas políticas / Governing climate change at local level : risks and policy responses

Barbi, Fabiana, 1980- 24 August 2018 (has links)
Orientadores: Leila da Costa Ferreira, Carlos Alfredo Joly / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-24T10:19:44Z (GMT). No. of bitstreams: 1 Barbi_Fabiana_D.pdf: 3791389 bytes, checksum: 643d52986788ca4e3ec62ffb7dc0af22 (MD5) Previous issue date: 2014 / Resumo: O objetivo dessa tese é analisar como os tomadores de decisão têm se apropriado dos riscos das mudanças climáticas em suas políticas locais e na integração com as políticas existentes, em diferentes níveis de governança. Para analisar o processo de internalização dos riscos das mudanças climáticas em termos de respostas políticas ao problema pelos governos locais e metropolitano, construiu-se uma matriz analítica baseada em quatro pontos: riscos das mudanças climáticas na região; estruturas político-institucionais para a questão climática; respostas políticas relacionadas às mudanças climáticas e percepções dos atores governamentais acerca do tema. Essa matriz analítica foi concebida a partir dos capítulos teóricos e utilizada no estudo em profundidade na cidade de Santos, na Região Metropolitana da Baixada Santista. Os resultados mostraram que essa região é bastante vulnerável aos riscos das mudanças climáticas e mostraram a existência de algumas ações governamentais relacionadas a essa questão em diferentes setores de atuação no nível local e metropolitano. Entretanto, nenhuma dessas ações está diretamente voltada a lidar com os riscos das mudanças climáticas, abordando essa questão de maneira tangencial. Os riscos das mudanças climáticas não estão sendo internalizados pelos governos em termos de respostas políticas, embora ações referentes a esses riscos sejam misturadas às respostas governamentais a outros problemas urbanos que possuem interface com a questão climática e podem ser exacerbados a partir das mudanças no clima. Na região estudada, os riscos das mudanças climáticas são internalizados como riscos naturais, isto é, as respostas políticas estão mais direcionadas aos riscos naturais do que aos riscos climáticos, não incorporando os cenários previstos de mudanças climáticas nas respostas governamentais. Os riscos das mudanças climáticas são produtos dos próprios processos de desenvolvimento das sociedades contemporâneas. Isso implica no questionamento desses processos. E isso, as políticas climáticas ou relacionadas às mudanças climáticas apresentadas nessa tese estão longe de lograr, ou seja, elas não vão ao cerne do problema, mas se configuram como paliativos que permitem manter os mesmos padrões de desenvolvimento conhecidos até aqui: poluidores e emissores de gases de efeito estufa / Abstract: The aim of this dissertation is to analyze how policy makers have internalized the risks of climate change in their local policies and have integrated them with existing policies at different levels of governance. In order to analyze the internalization process of climate change risks in terms of policy responses to the problem by local and metropolitan governments, an analytical matrix based on four points was constructed: the risks of climate change; political-institutional structures for the climate issue; climate-relate policy responses and the perceptions of governmental actors on the subject. This analytical matrix was based on the theoretical chapters and used in the in-depth study in the city of Santos, in the Santos Metropolitan Region. The results showed that this region is quite vulnerable to the risks of climate change and showed the existence of some government actions related to this issue in different sectors of activity, at the local and metropolitan levels. However, none of these actions is directly geared to deal with climate change risks, addressing them tangentially. The risks of climate change are not being internalized by governments in terms of policy responses, although actions related to these risks are mixed to other policy responses to urban problems that have interface with the climate issue and may be exacerbated by changes in the climate. In the study area, the risks of climate change are internalized as natural hazards, i.e., the political responses are more directed to natural hazards than to climate risks, without incorporating climate change scenarios into the political responses. Climate change risks are products of the development processes themselves in contemporary societies. This implies questioning these processes. The climate or climate-related policies presented in this thesis are far from achieving this, i.e., they do not go to the heart of the problem, but are configured as palliatives that allow the maintenance of the same development standards known so far: polluters and greenhouse gases emitters / Doutorado / Aspectos Sociais de Sustentabilidade e Conservação / Doutora em Ambiente e Sociedade
76

Hodnocení environmentálních rizik v průmyslovém podniku / Environmental risk assessment in industrial enterprise

Marada, Vojtěch January 2014 (has links)
Environmental risk assessment in industrial enterprise is important part of safety documentation required by legislation of the Czech Republic and of the EU. Despite that, there is given less attention to this part of risk analysis in the Czech Republic, than in the other countries of EU. Importance of this part is evident for a number of significant industrial accidents with impact to the environment. This Master’s thesis deals with the methods used in safety engineering for the environmental risk assessment, according to Act No. 59/2006 Coll., on the prevention of major accidents, as amended by later regulations. The thesis is divided into theoretical and practical part. Theoretical part includes the legislative summary of Act No. 59/2006 Coll. on the prevention of major accidents, as amended by later regulations and requirements for owners, which result from this law. Further, the frameworks for environmental risk assessment in the EU and USA were evaluated and compared. Main part deals with the characteristics of selected (most commonly used in practice) methods for environmental risk assessment, evaluation of its usability and creation of compact process for environmental risk assessment in industrial enterprise in accordance to legislative requirements. In the final part, there is performed application of suggested process for environmental risk assessment in the concrete industrial enterprise.
77

Effekter av vägsalt på träd och grundvatten i Stockholms stad : Miljöriskbedömning och åtgärdsförslag / Effects of road salt on trees and groundwater in the city of Stockholm : Environmental risk assessment and proposed measures

Ergün, Rukiyye January 2023 (has links)
För att motverka halka på vägar och skapa bättre framkomlighet och trafiksäkerhet för trafikanter under vintersäsonger, används halkskyddsmedel på vägarna. I dagsläget och sannolikt under en överskådlig framtid innebär det att man använder natriumkloridbaserade medel NaCl i form av vägsalt då NaCl är det mest effektiva samt kostnadseffektiva medlet för halkskydd. Trots att NaCl är det mest effektiva medlet mot halka kan vägsalt samtidigt orsaka vissa negativa effekter på miljön. Studier visar på att vägsaltet sprider sig i miljön genom flera olika transportmekanismer vilket gör vägsaltet till ett komplext problem. Vägsalt påverkar bland annat träden negativt, långvarig exponering för salt kan försvaga träden och leda till att träden dör. Klimatförändringar har potentialen att även i framtiden öka, om än kontraintuitivt, efterfrågan på vägsalt i städer med kallt vinterklimat. Därav behövs ett proaktivt tillvägagångssätt för att minska de negativa effekterna vägsaltet har på miljön och träden. Forskning visar på att det finns behov av mer kunskap samt kvalitativa studier gällande vägsalt och dess miljöeffekter. Hittills har det inte funnits någon probabilistisk metod för att bedöma miljörisken vägsalt utgör för gatuträden för att ge nödvändigt stöd till beslutsfattare. Riskbedömningar och riskhantering är viktiga medel i beslutstödjande arbeten. Syftet med denna studie har därav varit att utveckla, tillämpa och utvärdera modeller för övergripande miljöriskbedömningar av vägsalt som ett miljöförorenande ämne. För studien valdes två gator i Stockholms stad, Vasagatan samt Sockenvägen. Studien inleds med litteraturstudier som behandlar trädens roll i urbana miljöer, vägsaltets spridningsvägar, vägsaltets påverkan på träden och miljön samt olika saltmanagementmetoder. Baserade på data från litteraturstudien utfördes miljöriskbedömningar för träd-och vegetation, grundvatten samt jord i studieområdena. En riskbedömning utfördes för ett scenario där vägsalt inte används på vägarna och risken detta kan utgöra för människor. Vidare utvecklades och arbetades det fram olika åtgärdsförslag för studieområdena. Åtgärdsförslagen bedömdes och graderades i en bedömningsmatris. Sammantaget belyser studien vikten av att kontinuerligt samla in saltdata, skapa förståelse för vägsaltets spridningsvägar, utföra miljöriskanalyser på flera miljöområden gällande vägsalt, arbeta fram olika saltmanagementmetoder samt upprätta policyn för vägsalt i syfte att minimera vägsaltets skadliga effekter på träden och ekosystemen i Stockholms stad. / To prevent slippery roads and ensure better traffic safety for road-users during winter seasons, de-icing agents are used on the roads. Currently and probably for the foreseeable future this means using the sodium chloride-based agent NaCl in the form of road salt, which currently is the most effective and cost-effective de-icer. Despite benefits for road safety road salt can at the same time pose negative effects on the environment. Several studies describe how road salt spreads in the environment through several different transport mechanisms, which deems road salt a complex problem. Road salt affects, among other things trees negatively, prolonged exposure to salt weakens the trees and can lead to the death of the damaged trees. Climate change has the potential to even in the future, albeit counterintuitively, increase the demand for NaCl based road salt, during winter seasons in cities with continental climate, as road salt is a cost-effective agent. Hence, a proactive approach is needed to be able to reduce the negative effects road salt has on the environment and trees. Research shows there is a need for more knowledge and qualitative studies regarding road salt and its environmental effects and the effects on street trees. Until now there has been no probabilistic method to assess the environmental risks posed by road salt on street trees to provide the necessary support to decision makers. Environmental risk assessments and risk management are important tools in decision support. The aim of this study has therefore been to develop, apply and evaluate a model for an overall environmental risk assessment of road salt as a pollutant. For the study two streets were chosen in the city of Stockholm, Vasagatan and Sockenvägen. The study is introduced with literature studies on the roles of trees in urban environments, the dispersal paths of road salt, the impact of road salt on trees and the environment and road salt management methods. Based on data from the literature study an environmental risk assessment was carried out for trees and vegetation, ground water and soil in the study areas. A risk assessment was carried out for a scenario where road salt is not applied on the roads and the risk this may pose to human health. Furthermore, various suggestions for mitigation methods for the study areas were developed. The proposed mitigation measures were assessed and graded in an assessment matrix. The study highlights the importance of collecting road salt data continuously over several seasons, creating an understanding of road salt's dispersal paths, performing environmental risk assessments and analysis on several environmental areas regarding road salt. The study also highlights the need for developing different salt management methods and establishing policies aimed to reduce harmful effects of road salt on the trees and ecosystems in the city of Stockholm.
78

Utilizing soil characteristics, tissue residues, invertebrate exposures and invertebrate community analyses to evaluate a lead-contaminated site: A shooting range case study

Bowman, Sarah R. 16 September 2015 (has links)
No description available.
79

Environmental risk assessment for the electricity sector : a case of Swaziland electricity company

Van Zuydam, Constance Sthembile 06 1900 (has links)
The provision of reliable, safe, affordable and accessible power supply is one of the most important cornerstones for economic development, particularly for third world countries. Notwithstanding all known benefits of power supply, there are environmental risks associated with electricity generation, transmission and usage that need to be identified, assessed and managed. These risks range from minor to major risks such as serious bodily harm and fatalities as well as environmental degradation. In order to minimise and control the operational risks, it is key for the sector to ensure that the risks are identified and assessed using appropriate tools and systems to ensure sustainability and safe work environments. This study explored, improved and designed a tool for environmental risk assessment within Swaziland Electricity Company, (SEC) based on clause 4.3.1 of ISO 14001 (2004), Environmental Management System and Occupational Health and Safety Assessment Series, OHSAS 18001 (2007), Occupational Health and Safety System. The previous risk assessment and evaluation tool used in the company ignored existing risk control practices employed and thus did not truly quantify identified risks. The methodology presented in this study focused on the identification of hazards/aspects and risks associated with processes in electricity generation, transmission and distribution. Risks were evaluated and all possible measures to control the identified risks were suggested. The top three significant hazards identified include; exposure to live wires, road hazards and the use of uncertified/ defective/wrong equipment and/or machinery whilst the significant impacts were: soil pollution, natural resource degradation/ depletion, loss of flora and fauna and social impacts. The distribution department was observed to have the most environmental risks when compared to the other departments. The developed tool and data could be used as baseline information by other sectors wishing to implement environment and safety systems. It will also continually improve the safety and environmental performance of SEC. / Environmental Science / D. Phil. (Environmental Science)
80

Risk-based assessment of environmental asbestos contamination in the Northern Cape and North West provinces of South Africa

Jones, Robert Ryan January 2011 (has links)
The commercial mining of asbestos occurred in four Provinces of South Africa (Northern Cape, North West, Limpopo and Mpumalanga). It was initiated in the late 1800's and lasted for over a hundred years into the beginning of this century. As a producer of amphibole asbestos, South Africa far outpaced every other country being responsible for 97% of global production. The last crocidolite mine closed in 1996 and chrysotile in 2002. Anecdotal information concerning environmental contamination as a result of the former mining activities and the improper disposal of mine waste tailings has been reported by a variety of authors. Few comprehensive or systematic surveys have been conducted to date to document this issue and very little quantifiable research has been completed on the communities located in close proximity to the former mine sites to determine the extent of contamination. In 2004-2006 communities were surveyed within the Northern Cape and North West Provinces to determine the extent and severity of environmental contamination. This research developed and applied a methodology to select those communities suspected of environmental contamination, a targeted survey methodology, and a protocol for rapid sample laboratory analysis. A total of 41 communities were initially predicted by the model to be suspected for environmental asbestos contamination. Based on the inclusion of local knowledge, a final 36 communities were selected for a screening-level field assessment, 34 of which were found to contain environmental asbestos contamination at rates ranging from 20 to 100% of the surveyed locations. A total of 1 843 samples of soil and building material were collected in the screening level assessment. One community (Ga-Mopedi) was selected as being representative of the total cohort and a more detailed house to house survey was completed. A total of 1 486 samples were collected during the detailed survey. Results of the detailed survey revealed 26.2% of the homes were contaminated with asbestos containing soil and/or building material. A theoretical quantitative cumulative exposure assessment was developed to estimate the disease burden within the study area population of 126,130 individuals within the surveyed communities resulting in a predicted range of 25-52.4 excess deaths per year from lung cancer and mesothelioma due solely to environmental exposures to asbestos pollution.

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