• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 120
  • 108
  • 23
  • 17
  • 14
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 371
  • 371
  • 371
  • 108
  • 102
  • 94
  • 73
  • 68
  • 43
  • 37
  • 36
  • 32
  • 32
  • 31
  • 31
  • 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.
161

Interações entre linhas de transmissão e a biodiversidade : uma revisão sistemâtica dos efeitos induzidos por esses empreendimentos

Biasotto, Larissa Donida January 2017 (has links)
A crise na biodiversidade tem se agravado como resultado das atividades humanas. Identificar os efeitos ecológicos causados por empreendimentos, como linhas de transmissão de energia elétrica (LTs), é essencial para o planejamento dessas estruturas e para melhor informar seu processo de tomada de decisão. A Avaliação de Impacto Ambiental (AIA) é um importante instrumento para a minimização de impactos na biodiversidade. No entanto, uma das maiores deficiências para a mitigação de impactos está na ausência da antecipação dos mesmos na fase de planejamento das estruturas. Um dos objetivos deste estudo foi listar e descrever os potenciais efeitos ambientais causados pelas LTs, sua natureza e os componentes bióticos afetados. A partir de uma abordagem de revisão sistemática, a síntese dos estudos mostrou que as interações das linhas com a biodiversidade têm sido investigadas em uma grande amplitude de organismos, abordando doze diferentes efeitos no ambiente. No entanto, é notável a ausência de estudos relacionados a grupos funcionais de menor mobilidade e sobre efeitos como a perda de habitat. Além de listar e descrever os efeitos das LTs, este trabalho estruturou um modelo conceitual para auxiliar na definição do escopo das AIAs. Nós acreditamos que o reconhecimento antecipado do espectro de potenciais impactos, além de ser importante para a compreensão das cadeias causais pelas quais as ações de cada empreendimento conduzem efeitos, auxilia na qualificação do processo de licenciamento, direcionando os estudos para impactos prioritários. Como a forma mais efetiva de evitamento de impactos, nós recomendamos fortemente que iniciativas de espacialização dos mesmos sejam desenvolvidas para a futura incorporação no planejamento da expansão da rede de transmissão de energia. / The biodiversity crisis has worsened in the last decades, as a result of human activities. Identifying the ecological effects caused by infrastructure developments, such as electric power transmission lines (TLs), is essential for planning these developments and for better informing the decision-making process. Environmental Impact Assessment (EIA) is an important instrument to ensure the minimization of impacts on biodiversity. However, one of the major shortcomings for mitigation of impacts is the lack of anticipation in the planning phase of these developments. One of the objectives of this study was to list and describe the potential environmental effects caused by TLs, their nature and the affected biotic components. From a systematic review approach, the synthesis of the studies reveal that line interactions with biodiversity have been investigated over a wide range of organisms, addressing twelve different effects on the environment. However, the absence of studies related to functional groups of lower mobility and other effects, such as habitat loss, is notable. In addition to listing and describing the effects of LTs, this work structured a conceptual model to help define the scope of EIAs. We believe that the early recognition of the spectrum of potential impacts, in addition to being important for understanding the causal chains through which the actions of each undertaking have effects, helps in the qualification of the licensing process, directing the studies to priority impacts. As the most effective way of avoiding impacts, we strongly recommend that spatial analysis and investigation should be developed and incorporated in planning the expansion of the power transmission network.
162

Avaliação de impactos cumulativos para a biodiversidade: uma proposta de quadro de referência no contexto da avaliação de impacto ambiental de projetos. / Cumulative impacts assessment for biodiversity: a reference framework proposal in the context of the environmental impact assessment of projects.

Dibo, Ana Paula Alves 15 August 2018 (has links)
A avaliação de impactos cumulativos (AIC) é uma prática reconhecida e recomendada internacionalmente em processos de avaliação de impacto ambiental (AIA) de projetos, particularmente onde há concentração espacial de empreendimentos que podem causar significativos impactos, tendo como foco componentes ambientais selecionados que podem ser afetados pelos impactos de diversas ações. Assim, a AIC possibilita uma melhor compreensão das consequências ambientais, principalmente diante da crescente significância de fatores de risco, como os relacionados à biodiversidade. No Brasil, é deficiente a consideração de impactos cumulativos nos estudos de impacto ambiental (EIAs) de projetos submetidos ao licenciamento ambiental. Dentre as principais causas, destacam-se a ausência de diretrizes ou orientações técnicas ou metodológicas, tanto em nível estadual como nacional, e a dificuldade ao acesso de informações essenciais para a realização da AIC. Nesse contexto, para que essa prática possa avançar no Brasil, é necessário discutir os próprios fundamentos e objetivos da AIC, bem como seus desafios, e assim identificar oportunidades para a inclusão dessa prática na AIA de projetos. Ademais, ressalta-se a fundamental importância da adequada AIC sobre componentes ambientais relacionados à biodiversidade, tendo em vista as crescentes ameaças à integridade dos ecossistemas. Nesse sentido, esta pesquisa teve como objetivo propor um quadro de referência com diretrizes e recomendações de iniciativas de suporte, a fim de promover a integração da AIC para a biodiversidade na AIA de projetos. Para tal, a pesquisa foi realizada por meio do desenvolvimento das etapas: (i) elaboração do referencial teórico da pesquisa; (ii) discussão da prática da AIC sobre a biodiversidade no contexto do setor sucroenergético paulista, escolhido devido aos questionamentos sobre os impactos na biodiversidade decorrentes da expansão e concentração das áreas de cultivo de cana-de-açúcar; (iii) discussão da prática internacional em AIC em nível de projeto, considerando a experiência da AIC sobre a biodiversidade no Canadá, devido ao seu histórico e consolidação nesse país; e (iv) construção do quadro de referência para a AIC sobre a biodiversidade, tendo como base o contexto do estado de São Paulo. Como resultados: (i) foram identificados potenciais impactos cumulativos das áreas de cultivo de cana sobre componentes ambientais selecionados relacionados à biodiversidade; (ii) foi constatado que os Termos de Referência (TRs) elaborados no processo de licenciamento ambiental de empreendimentos do setor sucroenergético não apresentam orientação explícita para a realização da AIC sobre a biodiversidade; (iii) verificou-se que os EIAs apresentam informações sobre a biodiversidade que poderiam auxiliar na identificação e análise dos potenciais impactos cumulativos, porém não apresentam avaliação sistemática dos mesmos. A análise dos TRs e EIAs de quatro casos de estudo canadenses selecionados identificou lições aprendidas que poderiam ser refletidas ao contexto brasileiro. Considerando os resultados obtidos, foi elaborado um quadro de referência com diretrizes e recomendações de iniciativas para a integração da AIC para a biodiversidade no processo de AIA, considerando o contexto do estado de São Paulo. Conclui-se que as oportunidades identificadas podem contribuir para a integração estruturada da AIC para a biodiversidade à AIA de projetos submetidos ao licenciamento ambiental. / Cumulative impacts assessment (CIA) is a well-recognized and internationally recommended practice in environmental impact assessment (EIA) processes of projects, particularly where there is a spatial concentration of developments that can cause significant impacts, focusing on valued environmental components that may be affected by the impacts of various actions. Thus, CIA allows a better understanding of the environmental consequences, especially in view of the growing significance of risk factors, such as those related to biodiversity. In Brazil, there is a lack of considering cumulative impacts in the environmental impact statements (EISs) of projects submitted to the environmental licensing. Among the main causes, it is highlighted the lack of guidance or technical or methodological guidelines, both at the state and national level, as well as the difficulty in accessing essential information for the CIA. To improve this practice in Brazil, it is necessary to discuss the elements and purposes of CIA, as well as the challenges, and to identify opportunities for addressing this practice in EIA at project level. Further, it is important to adequately address CIA on components related to biodiversity, in view of the growing threats to the integrity of ecosystems. In this way, the aim of this research was to propose a reference framework with guidelines and recommendations of support initiatives to integrate CIA for biodiversity in the EIA of projects. The research was carried out through the following steps: (i) elaboration of the theoretical reference of the research; (ii) discussion of CIA practice on biodiversity in the context of São Paulo sugarcane industry; chosen due to questions about the impacts on biodiversity by the expansion and concentration of sugarcane areas; (iii) discussion of the international practice in CIA at the project level, considering the Canadian experience in CIA on biodiversity, due to its history and consolidation in that country; and (iv) development of the reference framework for CIA on biodiversity, based on the context of São Paulo state. As results: (i) potential cumulative impacts of sugarcane on valued environmental components related to biodiversity were identified; (ii) Terms of Reference (ToRs) prepared in the environmental licensing process of enterprises of the sugarcane industry do not present explicit guidance for conducting CIA on biodiversity; (iii) EISs present elements on biodiversity that could help in the discussion of potential cumulative impacts, but there is no systematic assessment. Four ToRs and EISs of selected Canadian case studies were analyzed with the identification of lessons learned that could be discussed in the Brazilian context. With the results obtained, a reference framework was developed with guidelines and recommendations of support initiatives to integrate the CIA for biodiversity in the EIA process, in the context of São Paulo state. The opportunities identified can contribute to integrate the CIA for biodiversity to the EIA of projects submitted to the environmental licensing process.
163

O princípio da precaução em conflitos socioambientais por recursos hídricos e mineração: estudo comparativo entre o Brasil e o Peru / The precautionary principle in socio-environmental conflicts by water resources and mining: a comparative study between Brazil and Peru

Rodriguez, Zenaida Luisa Lauda 31 July 2018 (has links)
Diferente da maioria dos conflitos socioambientais por recursos hídricos e mineração, nos últimos anos, têm surgido casos de conflitos cujas ações de resistência foram pautadas não pelos impactos ambientais gerados pela mineração, mas pela preocupação das populações com os possíveis riscos que geraria o projeto minerador nos seus territórios. Nestes casos, as comunidades se opuseram aos empreendimentos antes da implantação ou início de qualquer atividade da mineradora, ainda que as empresas contassem com licenças ambientais outorgadas pelas autoridades competentes. Para isso, além de atos de resistência, estas populações recorreram à judicialização do conflito com a invocação, entre outros argumentos, do Princípio da Precaução por possíveis graves e irreversíveis danos que o projeto minerador poderia causar sobre os recursos hídricos e os ecossistemas. Tais são os casos do projeto de mineração de fosfato de Anitápolis em Santa Catarina Brasil, e o projeto de mineração de ouro Conga em Cajamarca Peru. Devido à complexidade teórica do Princípio da Precaução, o objetivo deste trabalho é entender qual é a incidência e as implicações da invocação deste princípio no contexto de conflitos socioambientais por recursos hídricos e mineração. Para responder a este objetivo, este trabalho aborda o tema dos riscos e o princípio da precaução, assim como os instrumentos que materializam este princípio nos ordenamentos jurídicos do Brasil e no Peru, e propõe sua articulação teórica com três teorias que nos ajudam a entender a questão dos conflitos socioambientais: a ecologia política, a justiça ambiental e o póscolonialismo/decolonialidade. Através deste quadro analítico este trabalho mostra a conexão entre estas teorias e revela a importância deste tipo de conflitos iniciados pela percepção dos riscos contra projetos mineradores, aos quais denominamos como conflitos socioambientais precautórios. Em base a esta análise, este trabalho aponta os problemas das desigualdades de poder nos conflitos socioambientais por recursos hídricos e mineração, assim como a inclusão de um novo fator de conflitos baseado na percepção dos riscos, que merece especial tratamento pela dificuldade da sua análise. Todos estes elementos são observados nos dois casos de conflitos por recursos hídricos e mineração que são expostos em forma comparativa para revelar a incidência destes fatores e sua similaridade tanto no contexto peruano quanto brasileiro. / Unlike most socio-environmental conflicts over water resources and mining, in recent years there have been several cases of conflicts whose actions of resistance were based not on the environmental impacts generated by mining but on the population\'s concern with the possible risks that the mining project would generate in their territories. In these cases, the communities opposed to the projects prior to their implementation or commencement of any activity by mining company, even if the companies had the required environmental licenses. In addition to acts of resistance, these populations resorted to the judicialisation of the conflict with the invocation, among other arguments, of the Precautionary Principle due to possible serious and irreversible damage that the mining project could cause on water resources and ecosystems. Such are the cases of the Anitápolis phosphate mining project in Santa Catarina - Brazil, and the Conga gold mining project in Cajamarca - Peru. Due to the theoretical complexity of the Precautionary Principle, the objective of this work is to understand the incidence and implications of its invocation in the context of socio-environmental conflicts for water resources and mining. In order to achieve it, this work addresses the topic of risks and the precautionary principle, as well as the instruments that materialize this principle in the legal systems of Brazil and Peru, and proposes its theoretical articulation with three theories that help us to understand the environmental conflicts: political ecology, environmental justice and postcolonialism / decoloniality. This analytical framework shows the connection between these theories and reasserts the relevance of this type of conflicts initiated by the perception of the risks against mining projects, which we call \"social-environmental precautionary conflicts\". Based on this framework, this work points out the problems of power inequalities in socio-environmental conflicts for water resources and mining, as well as the inclusion of a new conflict factor, based on the perception of risks, that deserve special treatment due to its difficult analysis. All these elements are observed in the two cases of water and mining conflicts, that has been exposed comparatively in order to reveal the incidence of these factors and their similarity in both Peruvian and Brazilian contexts.
164

O sistema de licenciamento ambiental e o desafio econômico - proposta para o Estado de São Paulo. / The environmental licenses system and the economic challenge: a proposal for the state of São Paulo.

Paulo Ferreira 30 September 2010 (has links)
As conferências mundiais de meio ambiente de 1972 em Estocolmo e de 1992 no Rio de Janeiro trouxeram um novo despertar para a humanidade nas questões ambientais. Por outro lado, a globalização econômica ampliou de maneira extraordinária os fluxos de produção e comércio, inaugurando uma nova era de crescimento econômico, que trouxe como consequência novas oportunidades de desenvolvimento, mas também pressões sobre os ativos ambientais. A resposta às pressões tem sido um arcabouço legal de regulação, que tem, na visão de alguns, inibido o crescimento econômico e restringido as oportunidades de mobilidade social. As críticas estão concentradas, especialmente nos procedimentos de concessão das licenças ambientais, excessivamente burocráticos, e que acarretam custos econômicos, que reduzem a competitividade dos empreendimentos, principalmente os de infra-estrutura. O presente trabalho procurou analisar, comparativamente, a aplicação desses instrumentos em diversos países, em quatro continentes, com diferentes graus de desenvolvimento, população e nível de renda. Pesquisou as formas de aplicação dos instrumentos das políticas ambientais em diversos estados do Brasil, com suas diferenças de interpretação e de formas de atuação, sob o ponto de vista dos agentes governamentais, das entidades de classe e das organizações da sociedade civil. É apresentada uma análise crítica dos procedimentos e regulamentos em vigor no Estado de São Paulo, bem como é formulada uma proposta de atuação, que objetiva valorizar os procedimentos técnicos e reduzir os burocráticos; integrar as diferentes informações produzidas por diversos órgãos governamentais, importantes para o licenciamento; aumentar a transparência; fortalecer a participação popular e modernizar estruturas de acompanhamento e monitoramento pós-licença. / The 1972 Stockholm Environmental World Conference along with its counterpart held in 1992 in Rio de Janeiro generated a wake-up call to humanity regarding environmental issues. On the other hand economic globalization leveraged production and trade flow, launching a new era of economic growth, providing new development opportunities but also concentrating pressures over environmental assets. The response to these pressures has been a framework of legal regulation which has, according to some professionals, inhibited economic growth and restrained opportunities for social advancement. Current critics are focused mostly in excessively bureaucratic environmental permit procedures which carry on economic costs reducing a projects competitive advantage, mainly in infrastructure. The following work attempts to examine comparatively the application of these instruments in several countries, in four Continents, with different levels of development, population and income. Research was made on the various applications of the environmental policies instruments in several States of Brazil, with its differences in interpretation and decision making process, under the viewpoint of governmental officers, class entities and organizations within society. A critical analysis of the current procedures and regulations in the State of São Paulo is presented along with an engaging proposition that seeks to exalt technical procedures and reduce bureaucratic ones, integrate the diverse but relevant information generated by a number of governmental agencies, increase transparency, strengthen the participation of common people and modernize the follow up apparatus employed in monitoring activity after the permits are submitted.
165

Environmental impact assessment and process simulation of the tidal current energy resource in the Strait of Messina

El-Geziry, Tarek Mohamed Ahmed January 2010 (has links)
Interest in exploring renewable energy resources has increased globally, especially with recent worldwide intentions to maintain the global climate. Looking at the oceans as a vast sustainable clean energy resource to satisfy present high humankind energy demands has been strongly recommended. Several types of renewable energy resources exist in the oceans: waves, tides, thermal and salinity variations, currents, and offshore winds. Exploiting tidal currents is considered one of the most effective approaches to the generation of electricity. Tidal turbines are deployed beneath the sea surface to transfer the kinetic energy in tidal currents to mechanical energy suitable for ongoing conversion to electricity and subsequent transmission. However, choosing a suitable site to deploy these turbines is not a trivial process. Various constraints must be satisfied subject to basic criteria dependent upon local factors, technology limitation and economic consideration. In addition, an important issue to consider is taking care to harness energy from tidal currents with minimum possible impact on the surrounding environment. The present study justifies the nomination of the Strait of Messina as an exceptional tidal current energy resource within the Mediterranean Sea basin. The maximum tidal current velocity at spring peak tide through the Strait may exceed 3 m/s. This mainly results from the tidal phase-difference (180°) between the northern (Tyrrhenian Sea) and southern (Ionian Sea) tips of the Strait, associated with a difference of 0.27 m in tidal wave amplitudes. In addition, the complex coastline configuration of the Strait plays an important role in enhancing tidal current velocities. Therefore, the Strait of Messina fulfils the basic criterion (2 m/s tidal current velocity) to be considered as a valid tidal current energy resource. This massive tidal current energy resource is assessed in the present study. A detailed full desk-based Environmental Impact Assessment (EIA) study is performed using the interactive matrix approach in order to investigate the anticipated environmental impacts on the marine ecosystem of the Strait of Messina resulting from the harnessing of energy from its tidal currents. Through the EIA study the different environmental components, both biotic and abiotic, which may be affected by the energy extraction process, are explained. In addition, the proposed key project activities are listed; the likelihood of occurrence and the magnitude of impact interaction with the environmental components are evaluated. The final judgment matrix guides to make a right decision on the proposed project. From the resulted matrix, the major impacts do not exceed 10% of the total anticipated effects. The positive point is that all the expected impacts, including the majors, can be controlled and minimised to the lowest possible limits by applying a good monitoring programme. The University of Edinburgh “Tidal Flow Development (TFD)” numerical model is used to mimic the tidal environment of the Strait of Messina in different cases. The model successfully simulates the tidal flow regime within the Strait under some exceptional conditions. Modifications to the main numerical code and coefficients were necessary in the present research to adjust the model according to each case study. In the three different cases of simulation, using these exceptional coefficients, the model simulates the main tidal characteristics of the tidal flow within the Strait. According to the results of the numerical simulation process, tidal currents are more intensive close to the eastern coast of the Strait of Messina near to Punta Pezzo. This area is far from any ferry route between Italy and Sicily. The best location to deploy tidal turbines for the energy extraction process is therefore recommended to be within these surroundings. Finally, a physical (laboratory) model is used to simulate the flow regime within the Strait of Messina. The Particle Image Velocimetry (PIV) technique was applied in the flow-table tank at the University of Edinburgh. The physical model simulates the flow behaviour within the Strait of Messina to a satisfactory degree. The cyclonic and anti-cyclonic motions observed at the southern extremity of the Strait are also very well simulated. The results of the present study assure confidence in the use of tidal currents within the Strait of Messina as a renewable energy resource. The safety of the environment must be ensured by following environmental guidelines, respecting the energy extraction limits and by applying an effective monitoring programme. The later is strongly recommended to be an adaptive one in which higher environmental authorities are able to watch, revise and control the environmental team within the project. These authorities are also able to postpone the project in case of any severe environmental case. The simulation processes emphasize the effect of morphometry and topography in enhancing tidal currents in the Strait of Messina. Moreover, numerical simulation assures that the complex morphometry and bathymetry, in addition to the open boundaries of the Strait of Messina, are challenging issues for modellers in order to mimic the real tidal current resource in the case of the Strait of Messina. The study also strongly recommends applying a more effective numerical model than TFD to assess the tidal hydrodynamical environment before and after any proposed energy extraction process. This will certainly, with the EIA of the marine ecosystem, help to make a right decision about the proposed project in order to achieve the goal of using clean and clear renewable energy resources while maintaining both natural and hydrodynamical environments to the most possible safest degree.
166

O princípio da precaução em conflitos socioambientais por recursos hídricos e mineração: estudo comparativo entre o Brasil e o Peru / The precautionary principle in socio-environmental conflicts by water resources and mining: a comparative study between Brazil and Peru

Zenaida Luisa Lauda Rodriguez 31 July 2018 (has links)
Diferente da maioria dos conflitos socioambientais por recursos hídricos e mineração, nos últimos anos, têm surgido casos de conflitos cujas ações de resistência foram pautadas não pelos impactos ambientais gerados pela mineração, mas pela preocupação das populações com os possíveis riscos que geraria o projeto minerador nos seus territórios. Nestes casos, as comunidades se opuseram aos empreendimentos antes da implantação ou início de qualquer atividade da mineradora, ainda que as empresas contassem com licenças ambientais outorgadas pelas autoridades competentes. Para isso, além de atos de resistência, estas populações recorreram à judicialização do conflito com a invocação, entre outros argumentos, do Princípio da Precaução por possíveis graves e irreversíveis danos que o projeto minerador poderia causar sobre os recursos hídricos e os ecossistemas. Tais são os casos do projeto de mineração de fosfato de Anitápolis em Santa Catarina Brasil, e o projeto de mineração de ouro Conga em Cajamarca Peru. Devido à complexidade teórica do Princípio da Precaução, o objetivo deste trabalho é entender qual é a incidência e as implicações da invocação deste princípio no contexto de conflitos socioambientais por recursos hídricos e mineração. Para responder a este objetivo, este trabalho aborda o tema dos riscos e o princípio da precaução, assim como os instrumentos que materializam este princípio nos ordenamentos jurídicos do Brasil e no Peru, e propõe sua articulação teórica com três teorias que nos ajudam a entender a questão dos conflitos socioambientais: a ecologia política, a justiça ambiental e o póscolonialismo/decolonialidade. Através deste quadro analítico este trabalho mostra a conexão entre estas teorias e revela a importância deste tipo de conflitos iniciados pela percepção dos riscos contra projetos mineradores, aos quais denominamos como conflitos socioambientais precautórios. Em base a esta análise, este trabalho aponta os problemas das desigualdades de poder nos conflitos socioambientais por recursos hídricos e mineração, assim como a inclusão de um novo fator de conflitos baseado na percepção dos riscos, que merece especial tratamento pela dificuldade da sua análise. Todos estes elementos são observados nos dois casos de conflitos por recursos hídricos e mineração que são expostos em forma comparativa para revelar a incidência destes fatores e sua similaridade tanto no contexto peruano quanto brasileiro. / Unlike most socio-environmental conflicts over water resources and mining, in recent years there have been several cases of conflicts whose actions of resistance were based not on the environmental impacts generated by mining but on the population\'s concern with the possible risks that the mining project would generate in their territories. In these cases, the communities opposed to the projects prior to their implementation or commencement of any activity by mining company, even if the companies had the required environmental licenses. In addition to acts of resistance, these populations resorted to the judicialisation of the conflict with the invocation, among other arguments, of the Precautionary Principle due to possible serious and irreversible damage that the mining project could cause on water resources and ecosystems. Such are the cases of the Anitápolis phosphate mining project in Santa Catarina - Brazil, and the Conga gold mining project in Cajamarca - Peru. Due to the theoretical complexity of the Precautionary Principle, the objective of this work is to understand the incidence and implications of its invocation in the context of socio-environmental conflicts for water resources and mining. In order to achieve it, this work addresses the topic of risks and the precautionary principle, as well as the instruments that materialize this principle in the legal systems of Brazil and Peru, and proposes its theoretical articulation with three theories that help us to understand the environmental conflicts: political ecology, environmental justice and postcolonialism / decoloniality. This analytical framework shows the connection between these theories and reasserts the relevance of this type of conflicts initiated by the perception of the risks against mining projects, which we call \"social-environmental precautionary conflicts\". Based on this framework, this work points out the problems of power inequalities in socio-environmental conflicts for water resources and mining, as well as the inclusion of a new conflict factor, based on the perception of risks, that deserve special treatment due to its difficult analysis. All these elements are observed in the two cases of water and mining conflicts, that has been exposed comparatively in order to reveal the incidence of these factors and their similarity in both Peruvian and Brazilian contexts.
167

Limitations to plant root growth in highly saline and alkaline bauxite residue

Kopittke, Peter Martin Unknown Date (has links)
Revegetation of bauxite residue is hampered by a lack of understanding of the limitations imposed on plant growth in highly saline and alkaline growth mediums. In this study, several of these growth limiting factors were investigated. The toxicity of the hydroxyl ion (OH-) was examined using a solution culture system developed to allow studies at high pH without nutritional limitations. Also using this solution culture system, the effect of the high Na and Mg concentrations of bauxite residue on the Ca nutrition of plants was investigated. As the toxicity of Al at high pH is not known, a study was conducted to examine the rhizotoxicity of aluminate (Al(OH)4-) and polycationic Al at high pH. The ability of plant roots to reduce rhizosphere pH in bauxite residue was also considered. A novel gypsum application method was assessed for its efficiency at improving the Ca status of bauxite residue. Manual adjustment, ion exchange resins and automated titration were examined for their suitability for nutrient solution pH control in alkaline conditions. For short-term studies, it was found that a solution without supply of Cu, Fe, Mn and Zn, and aerated with CO2 depleted air, greatly reduced nutrient precipitation at high pH, thus eliminating nutritional differences between treatments. Manual pH adjustment and the use of ion exchange resins as pH buffers were unsuitable methods of pH control. In contrast, pH control by automated titration had little effect on solution composition while maintaining constant pH. The solution culture system was used to examine OH- toxicity in mungbeans (Vigna radiata (L.) Wilczek cv. Emerald), with root length reduced at a bulk solution pH of 8.5 and greater. The effect of Ca activity ratio (CAR) and pH on Ca uptake by mungbeans and Rhodes grass (Chloris gayana cv. Pioneer) in Na dominated solution cultures and in soil was investigated. Changes in pH in the alkaline range were shown to have no effect on the critical CAR of 0.024 (corresponding to 90 % relative root length) for mungbeans grown in solution culture. Results from soil grown mungbeans confirmed those from solution culture, with a critical CAR of 0.025. A critical CAR of 0.034 was also established for soil grown Rhodes grass. However, using dilute nutrient solutions dominated by Mg at pH 9.0, root growth was found to be more limited than had been observed for Na solutions, with growth reduced beneath a critical CAR of 0.050. Using a CAR equation modified with plasma membrane binding constants (to incorporate the differing antagonistic effects of Mg and Na), new critical CAR values were calculated for Na (0.56) and Mg (0.44) dominated solutions. This modified CAR equation permits the calculation of CAR irrespective of the dominant salt present. Solubilities of various gypsum sources and size fractions in seawater were studied to investigate the effectiveness of gypsum addition to the residue sand pipeline, rather than as a direct field application. The dissolution rate constant varied with gypsum source (analytical grade (AR) > phosphogypsum (PG) > mined gypsum (MG)) due to reactivity and surface area differences, generally reaching saturation within 15 s (AR) to 30 min (MG > 2.0). The ability of bauxite residue to remove Ca from solution (due to cation exchange and precipitation) was also examined; the quantity of the total solution Ca adsorbed was found to be small (5 %). These low rates of solution Ca adsorption, comparatively rapid dissolution rates, and long pumping times (20 min), preclude the application of gypsum to the residue sand/seawater slurry as a method for residue amelioration. Dilute, alkaline (pH 9.5) nutrient solutions were used to investigate the effects of aluminate (Al(OH)4-) on mungbean root growth. Although root growth in Al(OH)4- solutions was slightly limited, the symptoms associated with this growth reduction were observed to be similar to those caused by the Al13 polycation at concentrations lower than that which can be detected. Also, when roots displaying these symptoms were transferred to fresh Al(OH)4- solutions, no root tip lesions were observed, and root hair growth on the lateral roots improved. Thus, Al(OH)4- is considered to be non-toxic, with the observed reduction in root growth in solutions containing Al(OH)4- due to the gradual formation of toxic Al13 in the bulk nutrient solution resulting from the acidification of the alkaline nutrient solution by the plant roots. The effect of Mn deficiency in Rhodes grass and of legume inoculation in lucerne (Medicago sativa L. cv. Hunter River), on the rhizosphere pH of plants grown in highly alkaline bauxite residue was investigated. In response to Mn deficiency in residue sand, Rhodes grass was observed to increase acidification of its rhizosphere (being up to 1.22 pH units lower than the bulk soil). Due to its ability to fix atmospheric N2 rather than relying on soil N (NO3-) reserves, inoculated lucerne (1.75 pH unit decrease) was also found to acidify its rhizosphere to a greater extent than non-inoculated lucerne (1.16 pH unit decrease).
168

Limitations to plant root growth in highly saline and alkaline bauxite residue

Kopittke, Peter Martin Unknown Date (has links)
Revegetation of bauxite residue is hampered by a lack of understanding of the limitations imposed on plant growth in highly saline and alkaline growth mediums. In this study, several of these growth limiting factors were investigated. The toxicity of the hydroxyl ion (OH-) was examined using a solution culture system developed to allow studies at high pH without nutritional limitations. Also using this solution culture system, the effect of the high Na and Mg concentrations of bauxite residue on the Ca nutrition of plants was investigated. As the toxicity of Al at high pH is not known, a study was conducted to examine the rhizotoxicity of aluminate (Al(OH)4-) and polycationic Al at high pH. The ability of plant roots to reduce rhizosphere pH in bauxite residue was also considered. A novel gypsum application method was assessed for its efficiency at improving the Ca status of bauxite residue. Manual adjustment, ion exchange resins and automated titration were examined for their suitability for nutrient solution pH control in alkaline conditions. For short-term studies, it was found that a solution without supply of Cu, Fe, Mn and Zn, and aerated with CO2 depleted air, greatly reduced nutrient precipitation at high pH, thus eliminating nutritional differences between treatments. Manual pH adjustment and the use of ion exchange resins as pH buffers were unsuitable methods of pH control. In contrast, pH control by automated titration had little effect on solution composition while maintaining constant pH. The solution culture system was used to examine OH- toxicity in mungbeans (Vigna radiata (L.) Wilczek cv. Emerald), with root length reduced at a bulk solution pH of 8.5 and greater. The effect of Ca activity ratio (CAR) and pH on Ca uptake by mungbeans and Rhodes grass (Chloris gayana cv. Pioneer) in Na dominated solution cultures and in soil was investigated. Changes in pH in the alkaline range were shown to have no effect on the critical CAR of 0.024 (corresponding to 90 % relative root length) for mungbeans grown in solution culture. Results from soil grown mungbeans confirmed those from solution culture, with a critical CAR of 0.025. A critical CAR of 0.034 was also established for soil grown Rhodes grass. However, using dilute nutrient solutions dominated by Mg at pH 9.0, root growth was found to be more limited than had been observed for Na solutions, with growth reduced beneath a critical CAR of 0.050. Using a CAR equation modified with plasma membrane binding constants (to incorporate the differing antagonistic effects of Mg and Na), new critical CAR values were calculated for Na (0.56) and Mg (0.44) dominated solutions. This modified CAR equation permits the calculation of CAR irrespective of the dominant salt present. Solubilities of various gypsum sources and size fractions in seawater were studied to investigate the effectiveness of gypsum addition to the residue sand pipeline, rather than as a direct field application. The dissolution rate constant varied with gypsum source (analytical grade (AR) > phosphogypsum (PG) > mined gypsum (MG)) due to reactivity and surface area differences, generally reaching saturation within 15 s (AR) to 30 min (MG > 2.0). The ability of bauxite residue to remove Ca from solution (due to cation exchange and precipitation) was also examined; the quantity of the total solution Ca adsorbed was found to be small (5 %). These low rates of solution Ca adsorption, comparatively rapid dissolution rates, and long pumping times (20 min), preclude the application of gypsum to the residue sand/seawater slurry as a method for residue amelioration. Dilute, alkaline (pH 9.5) nutrient solutions were used to investigate the effects of aluminate (Al(OH)4-) on mungbean root growth. Although root growth in Al(OH)4- solutions was slightly limited, the symptoms associated with this growth reduction were observed to be similar to those caused by the Al13 polycation at concentrations lower than that which can be detected. Also, when roots displaying these symptoms were transferred to fresh Al(OH)4- solutions, no root tip lesions were observed, and root hair growth on the lateral roots improved. Thus, Al(OH)4- is considered to be non-toxic, with the observed reduction in root growth in solutions containing Al(OH)4- due to the gradual formation of toxic Al13 in the bulk nutrient solution resulting from the acidification of the alkaline nutrient solution by the plant roots. The effect of Mn deficiency in Rhodes grass and of legume inoculation in lucerne (Medicago sativa L. cv. Hunter River), on the rhizosphere pH of plants grown in highly alkaline bauxite residue was investigated. In response to Mn deficiency in residue sand, Rhodes grass was observed to increase acidification of its rhizosphere (being up to 1.22 pH units lower than the bulk soil). Due to its ability to fix atmospheric N2 rather than relying on soil N (NO3-) reserves, inoculated lucerne (1.75 pH unit decrease) was also found to acidify its rhizosphere to a greater extent than non-inoculated lucerne (1.16 pH unit decrease).
169

Tillämpning av GIS-analyser i MKB / Application of GIS-analyses in EIA

Wall, Erik January 2006 (has links)
The reason for performing an Environmental Impact Assessment (EIA) is to incorporate environmental concern in different kinds of plans and projects. The purpose of such an assessment is to identify and describe direct, indirect and cumulative environmental impacts. Geographical Information System (GIS) is a tool that can be used to combine spatial extension of both sensitive areas and different environmental impacts in a quick and easy way. Because of that, descriptions of environmental impacts and motivation of different standpoints on a specific issue can be more correct and easier to make if GIS is used as a tool. Hence, GIS can contribute to improve the quality of Environmental Impact Assessments. If the benefits of using GIS are to out weight the costs, geographical information of satisfactory detail, actuality and accuracy need to be available at reasonable prices. In this paper, case studies are carried out for three different geographical analyses to investigate the use of GIS as a tool in EIA. From these case studies, more general conclusions about the benefits and limitations of using GIS for Environmental Impact Assessments are also drawn. The criteria, after which benefits and limitations of GIS have been estimated, are data availability, time consumption for performing the analyses and how the results from the performed analyses can make impact assessments easier, motivate different standpoints and increase the comprehensiveness of the EIA-report. The three different GIS-analyses includes calculation of pollution load in a catchment area, estimation of the visual impact from planned buildings and generation of alternative locations for underwater pipes. These analyses have been applied on one ongoing EIA for a freight terminal and one ongoing EIA for an underwater wastewater transmission pipe. The analyses in these case studies have been undertaken with ArcGIS software using the extensions “Spatial Analyst” and “3D Analyst”. It is shown in this study that due to uncertainty in available model values and the time consuming data manipulation, it is unlikely that calculations of pollution loads with GIS will be used to any larger extent in EIA. To carry out visual assessments with help of GIS to estimate visual impacts is on the other hand assumed to be useful in EIA-work. Both to assess impacts and to estimate how changes in building design can alter those impacts. To use GIS to produce alternative locations for underwater pipes is also considered valuable in EIA-work, even though there is a considerable lack of data to predict the environmental class of marine areas and the connections between available data and real environmental values are weak. However, the risk of damaging vulnerable and high valued marine areas should decrease when applying this type of analyse. / Miljökonsekvensbeskrivningar (MKB) genomförs för att möjliggöra att hänsyn om miljön tas vid olika typer av exploateringsprojekt och exploateringsplaner. Syftet med en miljökonsekvensbeskrivning är att identifiera och beskriva direkta, indirekta och kumulativa miljöeffekter. Geografiska informationssystem (GIS) är ett verktyg som kan användas för att snabbt och enkelt kombinera rumslig utsträckning av både känsliga områden och olika miljökonsekvenser. GIS kan därför användas för att underlätta beskrivningar av miljökonsekvenser och motivera olika ställningstaganden. Därigenom kan GIS bidra till bättre grundade och mer rättvisande miljökonsekvensbeskrivningar. Men för att vinsterna av att genomföra GIS-analyser ska överstiga kostnaderna krävs att geografisk information av tillräcklig detaljeringsgrad, aktualitet och säkerhet finns att tillgå till rimliga kostnader. Syftet med denna studie har varit att genom fallstudier undersöka om tre olika GIS-analyser kan användas som verktyg i miljöbedömningar med idag tillgänglig data, samt att utifrån fallstudierna dra mer allmänna slutsatser om vinster och begränsningar av att använda GIS i miljökonsekvensbeskrivningar. De kriterier som har använts för att bedöma vinster och begränsningar är tidsåtgång för analyserna, tillgång på data samt hur analyserna kan vara ett stöd i MKB-arbetet genom att underlätta beskrivningar av konsekvenser, motivera ställningstaganden som görs och öka rapportens begriplighet. De tre genomförda GIS-analyserna innefattar beräkning av föroreningsbelastning inom ett avrinningsområde, bedömning av byggnaders landskapspåverkan genom synlighetsanalys samt generering av förslag till alternativ ledningsdragning för en undervattensledning. Dessa analyser har tillämpats på en pågående MKB för en detaljplan för en partihall och en pågående MKB för en avloppsvattenledning under vatten. Analyserna i fallstudierna har genomförts i programmet ArcGIS med tilläggen ”Spatial Analyst” och ”3D Analyst”. Studien visar att det på grund av osäkerheter i tillgängliga schablonvärden och tidsåtgång för databehandling är osannolikt att beräkning av föroreningsmängd inom ett avrinningsområde med GIS kommer att användas till någon större utsträckning i MKB. Att med GIS genomföra synlighetsanalyser för att utvärdera landskapspåverkan bedöms däremot kunna användas i MKB, både för att bedöma påverkan och för att utvärdera hur en förändring i en byggnads utformning kan förändra den påverkan. Även att med GIS generera förslag till alternativa ledningsdragningar under vatten bedöms kunna fylla en funktion i MKB trots att tillgången på data för att kunna beskriva olika marina områdens naturvärden är klart bristfällig och kopplingen mellan tillgängliga data och verkliga naturvärden är osäker. Denna typ av analys bör ändå minska risken att värdefulla och skyddsvärda marina områden skadas vid lednignsdragning.
170

The Mechanism of Long-Term Environmental Impact Assessment for Large Oil Spill Events

Tsao, Kai 19 October 2011 (has links)
Ever since humans began using cargo by sea to transport oil, oil spill incidents have occurred on different scales in different environments. Oil leaks by cargo tankers on the high seas have a bigger and more serious impact on the environment. Among the many oil spills in the ocean, the most serious was the Exxon Valdez incident in Alaska¡¦s Prince William Sound (PWS). While it may not have been the largest spill in terms of the volume of oil leaked, its effects were far-reaching; the location of the spill was in the sensitive area between the temperate and subtropical zones, and it was home to many fish, migratory birds, and mammals. Therefore, this location has become an important place for researchers to study the environmental and biological impacts of an oil leak. In the past, there have been several studies conducted from various perspectives and in various stages. In 2001, the Greek oil tanker The Amorgos ran aground near Kenting National Park¡¦s Long-Keng Environmental Protection Zone and seriously damaged the ecological environment. Taiwanese studies on the ecological impacts of oil spills include investigations and evaluations done on a short-term basis, and have been mainly focused on contingency plans and designs, evaluation systems, and handling technology. Thus, the purpose of this paper is to use related studies conducted in Alaska PWS to evaluate the ecological system in the Long-Keng area and to assess the long-term impacts of an oil spill in the ecological sensitive area of Taiwan.

Page generated in 0.1031 seconds