Includes bibliographical references (leaves [268]-285) / xiv, 285, [85] leaves : ill. (some folded), maps (col., folded) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geographical and Environmental Studies, 2002

Includes bibliographical references (leaves [268]-285) / xiv, 285, [85] leaves : ill. (some folded), maps (col., folded) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geographical and Environmental Studies, 2002

Streams and rivers are examples of vital ecosystems that frequently undergo various environmental and anthropogenic stresses. A core question in population ecology is whether a given population will persist under changing ecological conditions. This thesis consists of three papers and is devoted to the mathematical analysis of responses of river-dwelling species to population persistence threats. The first paper presents a stochastic approach to the 'drift paradox' problem, where the classical reaction-advection-diffusion model is replaced by a birth-death-emigration process. We explore the effects of temporally varying flow on the persistence probability and highlight the importance of the benthic stage for the persistence of stream organisms. The second paper addresses the problem of river network fragmentation through disconnecting structures such as dams. We construct a population matrix model that incorporates the spatial structure of the studied river network and compare structural connectivity to an indicator of population persistence. The third paper adapts the same basic matrix model to examine fish response to disturbances travelling downstream from upstream sites. The study of these three aspects of persistence challenges for river populations contributes to the cumulative effects assessment on river networks.

A avaliação de efeitos cumulativos e sinérgicos constitui um elemento essencial à boa prática da Avaliação de Impacto Ambiental (AIA), no sentido do fortalecimento do processo de tomada de decisão e integração de aspectos ambientais no planejamento das atividades econômicas, mas a despeito da sua importância, a cumulatividade dos impactos é vista como um elemento que aumenta a complexidade do processo de AIA. Uma perspectiva promissora para a integração dos efeitos ambientais cumulativos no processo de AIA tem sido contemplada a partir inclusão da gestão dos impactos ao ciclo de avaliação de efeitos cumulativos, representada neste caso pela abordagem da Avaliação e Gestão de Efeitos Cumulativos (AGEC). Tendo em vista as limitações apontadas para o Brasil em relação à avaliação de efeitos cumulativos, considera-se relevante verificar em que medida a experiência consolidada de AGEC no contexto internacional poderia contribuir para o aperfeiçoamento da AIA no país. Deste modo, o presente trabalho é voltado para a identificação de boas práticas em AGEC no contexto brasileiro, valendo-se do estudo do caso da Coordenação Geral de Petróleo e Gás (CGPEG) do Instituto Brasileiro de Meio Ambiente e Recursos Naturais Renováveis (IBAMA), responsável pelos processos de licenciamento ambiental de sistemas de produção de petróleo e gás no país. Por meio de uma abordagem metodológica baseada na triangulação entre literatura, documentação, e entrevistas junto ao corpo técnico do órgão ambiental, foram identificadas oportunidades e dificuldades para a aplicação de AGEC no âmbito de atuação da CGPEG. Os resultados indicam que a prática da AGEC encontra-se em fase inicial de desenvolvimento, com a identificação de algumas evidências de boas práticas devidamente internalizadas pelo órgão ambiental, como a abordagem regionalizada e a utilização de metodologia semelhante às práticas internacionais identificadas. Nota-se também o esforço da CGPEG em promover uma atuação mais eficiente e integradora, exigindo programas regionalizados com visão sistêmica, o que leva a ganhos de longo prazo nas atividades de avaliação do corpo técnico. Como destaque está a prática inovadora do Projeto de Avaliação de Impactos Cumulativos (PAIC) no licenciamento da produção de petróleo da camada pré-sal da bacia de Santos, como referência para o órgão, em que houve contribuições significativas por parte de stakeholders mobilizados em espaços de acompanhamento da instalação da cadeia petrolífera na região e resolução de conflitos, o que sugere um quadro promissor para investimentos em sua estruturação e na capacitação de seu corpo técnico e gerencial, com vistas ao aprimoramento da atuação orientada para os efeitos cumulativos. / The evaluation of cumulative and synergistic effects consists in an essential element for Environmental Impact Assessment (EIA) good practices, in the sense that it enhances the decision-making process and environmental aspects integration in development planning. Despite its importance, impact accumulation is seen as adding complexity to EIA process. A promising perspective to integrate cumulative environmental effects on EIA process starts at implementing management to cumulative assessments, in this case represented by Cumulative Environmental Assessment and Management (CEAM) approach. Also recognizing Brazil\'s limitation to implement cumulative effects assessment, it is relevant to verify at which extent internationally recognized CEAM practices can improve the country EIA process. Therefore, the present study aims to identify CEAM good practices on Brazilian context, using a federal agency responsible for oil and gas environmental licensing, the \"Coordenadoria Geral de Petróleo e Gás\" (CGPEG/IBAMA). Using triangulation of methods, starting by literature review on good practices, documents and norms content analysis and semistructured interviews with CGPEG technicians, opportunities and difficulties for CEAM implementation were identified for agency performance. Results shows CEAM practices still in its early stages of development, with good practices adoption evidences for the agency, striving forth cumulative effects performance improvement. Also, CGPEG singular functional structure promotes long therm benefits for technical analysis, such as demanding a more integrated and regional approach in environmental monitoring programs. A innovative practice is the cumulative impacts assessment project demanded at the environmental licensing for Santos\' basin pre-salt layer oil and gas production, or \"Projeto de Avaliação de Impactos Cumulativos\" (PAIC), a \"reccomended administrative process\", seen as a orientative material for oil and gas future projects. The PAIC development context had important stakeholder contribuitions on public particiapion processes, such as follow-up foruns for community discussion over oil industries installation at São Paulo\'s North Coast.

A avaliação de efeitos cumulativos e sinérgicos constitui um elemento essencial à boa prática da Avaliação de Impacto Ambiental (AIA), no sentido do fortalecimento do processo de tomada de decisão e integração de aspectos ambientais no planejamento das atividades econômicas, mas a despeito da sua importância, a cumulatividade dos impactos é vista como um elemento que aumenta a complexidade do processo de AIA. Uma perspectiva promissora para a integração dos efeitos ambientais cumulativos no processo de AIA tem sido contemplada a partir inclusão da gestão dos impactos ao ciclo de avaliação de efeitos cumulativos, representada neste caso pela abordagem da Avaliação e Gestão de Efeitos Cumulativos (AGEC). Tendo em vista as limitações apontadas para o Brasil em relação à avaliação de efeitos cumulativos, considera-se relevante verificar em que medida a experiência consolidada de AGEC no contexto internacional poderia contribuir para o aperfeiçoamento da AIA no país. Deste modo, o presente trabalho é voltado para a identificação de boas práticas em AGEC no contexto brasileiro, valendo-se do estudo do caso da Coordenação Geral de Petróleo e Gás (CGPEG) do Instituto Brasileiro de Meio Ambiente e Recursos Naturais Renováveis (IBAMA), responsável pelos processos de licenciamento ambiental de sistemas de produção de petróleo e gás no país. Por meio de uma abordagem metodológica baseada na triangulação entre literatura, documentação, e entrevistas junto ao corpo técnico do órgão ambiental, foram identificadas oportunidades e dificuldades para a aplicação de AGEC no âmbito de atuação da CGPEG. Os resultados indicam que a prática da AGEC encontra-se em fase inicial de desenvolvimento, com a identificação de algumas evidências de boas práticas devidamente internalizadas pelo órgão ambiental, como a abordagem regionalizada e a utilização de metodologia semelhante às práticas internacionais identificadas. Nota-se também o esforço da CGPEG em promover uma atuação mais eficiente e integradora, exigindo programas regionalizados com visão sistêmica, o que leva a ganhos de longo prazo nas atividades de avaliação do corpo técnico. Como destaque está a prática inovadora do Projeto de Avaliação de Impactos Cumulativos (PAIC) no licenciamento da produção de petróleo da camada pré-sal da bacia de Santos, como referência para o órgão, em que houve contribuições significativas por parte de stakeholders mobilizados em espaços de acompanhamento da instalação da cadeia petrolífera na região e resolução de conflitos, o que sugere um quadro promissor para investimentos em sua estruturação e na capacitação de seu corpo técnico e gerencial, com vistas ao aprimoramento da atuação orientada para os efeitos cumulativos. / The evaluation of cumulative and synergistic effects consists in an essential element for Environmental Impact Assessment (EIA) good practices, in the sense that it enhances the decision-making process and environmental aspects integration in development planning. Despite its importance, impact accumulation is seen as adding complexity to EIA process. A promising perspective to integrate cumulative environmental effects on EIA process starts at implementing management to cumulative assessments, in this case represented by Cumulative Environmental Assessment and Management (CEAM) approach. Also recognizing Brazil\'s limitation to implement cumulative effects assessment, it is relevant to verify at which extent internationally recognized CEAM practices can improve the country EIA process. Therefore, the present study aims to identify CEAM good practices on Brazilian context, using a federal agency responsible for oil and gas environmental licensing, the \"Coordenadoria Geral de Petróleo e Gás\" (CGPEG/IBAMA). Using triangulation of methods, starting by literature review on good practices, documents and norms content analysis and semistructured interviews with CGPEG technicians, opportunities and difficulties for CEAM implementation were identified for agency performance. Results shows CEAM practices still in its early stages of development, with good practices adoption evidences for the agency, striving forth cumulative effects performance improvement. Also, CGPEG singular functional structure promotes long therm benefits for technical analysis, such as demanding a more integrated and regional approach in environmental monitoring programs. A innovative practice is the cumulative impacts assessment project demanded at the environmental licensing for Santos\' basin pre-salt layer oil and gas production, or \"Projeto de Avaliação de Impactos Cumulativos\" (PAIC), a \"reccomended administrative process\", seen as a orientative material for oil and gas future projects. The PAIC development context had important stakeholder contribuitions on public particiapion processes, such as follow-up foruns for community discussion over oil industries installation at São Paulo\'s North Coast.

This dissertation describes a proposed methodology for Cumulative Effects Assessment (CEA) with the purpose of improving the process by making it both more substantive and quantitative. The general principles of the approach include the following: use of effect-based analyses where selected Valued Component (VC) sensitivities are identified first and then effect pathways are determined building bottom-up linkages from VC sensitivities to potential stressors or combinations of stressors to effect drivers and forces behind the drivers. Models were developed based on statistical or historic trend analysis or literature review that predicted the responses of the VCs to changes in effect drivers. Further, scenarios of divergent futures were created that involved different developments of each effect driver or force, and finally the models were applied to each scenario to project the state of the studied VCs. A practical implementation was conducted to demonstrate the use of the proposed methods on future population trends of two anadromous salmon species from the Cowichan River, British Columbia, Chinook and Coho. The assessment was conducted for both early freshwater and marine phases of their life. For the freshwater phase, the assessment focused on two main factors affecting salmon survival, streamflow and stream temperature and established two main drivers affecting these stressors, land use and climate change, and two main forces behind these drivers, Local and Global human development driven change, respectively. Effects of stream temperature and streamflow on salmon freshwater survival were simulated using two models; one was based on Chinook freshwater survival correlations with stream temperature and was developed only for Chinook, and the other was based on literature-derived temperature and streamflow thresholds and was developed for both species. Connections between the stressors (stream temperature and streamflow) and drivers (land use and climate change) were established through a hydrologic model and stream temperature regression model. For the marine environment, models were created using Pearson correlation and stepwise regression analysis examining links between survival of Cowichan River Chinook and Strait of Georgia hatchery-raised and wild Coho and various environmental variables of the nearshore zone of Strait of Georgia and Juan de Fuca Strait. The models were applied to project future salmon survival under four future scenarios for 2050 that were created by combining two opposite scenarios of land use in the watershed, forest conservation and development, and two climate change scenarios, extreme and moderate. Scenario projections showed a decrease in overall (combined early freshwater marine) survival by 2050 for all three studied salmon populations. None of them are likely to survive in scenarios with extreme climate change, while scenarios with moderate climate change showed positive survival rates although lower than present-day baseline levels. Analysis also showed that land use management within the Cowichan River watershed can also affect freshwater survival of both Chinook and Coho and marine survival of Chinook through influence of river discharge on nearshore processes. However, our land-use management scenarios have considerably weaker effect than climate change on salmon survival. Therefore, we conclude that land use management alone is not sufficient to offset effects of climate change on salmon survival. / Graduate