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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.
131

Valores de referÃncia de qualidade para metais pesados em solos de mangue do Estado do CearÃ: subsÃdios para gestÃo da zona costeira. / Quality reference values for heavy metals in mangrove soils of the State of CearÃ: subsidies for coastal zone management.

Camila Campos Lopes Moreira 27 August 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Currently, activities related to urbanization and industrialization have contributed to increased concentrations of heavy metals in different types of soil. These elements have significant toxicity and can accumulate in the environment, configuring serious risk to human health and ecosystems in general. Thus, there is an increasing concern among countries in adopting an efficient environmental policy and, thus, the determination of natural concentration (background levels) of metals in soils and the consequent establishment of Quality Reference Values (QRV) are reality in some countries, including Brazil. However, there is a lack of studies like these related to soils under mangrove forests in the country, where these areas play very important roles and services in the environment. In this context, the contamination of mangrove soils by heavy metals is one of the major environmental issues today and may even compromise the estuaries throughout its length. Thus, a study was carried out in mangrove soils of the State of Cearà aiming their classification and characterization, beyond the determination of natural levels of metals in these soils and the consequent proposition of their QRV. For this, physical, chemical and mineralogical analyzes were realized, beyond the metals extraction by methods of semitotal digestion (EPA 3051A and aqua regia) and the determination of QRV was performed in accordance with the resolution 420/2009 of CONAMA. The results indicated that the semiarid climate preponderant in this region explains the behavior of the main attributes of these soils (ex: EC, TOC, mineral composition). It was also found that the levels of metals in these soils are influenced by the intensity of anthropogenic interference in the coastal environments, given that mangrove soils of Cearà River estuary, inserted into urban context and subjected to environmental stresses, showed the highest enrichment factors of metals. On the other hand, it was observed that the distribution of these elements in this environment is also regulated by interactions between the metals themselves and with attributes as clay and Fe and Mn oxides. Furthermore, the aqua regia digestion was efficient in extracting metals in these soils, while EPA 3051A, indicated by CONAMA for soil quality assessments, underestimated the available levels of metals in the analyzed soils. Given the above, the natural levels of metals determined in this study can serve as a basis for defining QRV for mangrove soils of the State of CearÃ, assisting the environmental agency in the formulation of a specific legislation for monitoring mangrove areas in the State, thus setting a new perspective for the management of estuarine environments. / Nos dias de hoje, atividades relacionadas à urbanizaÃÃo e à industrializaÃÃo tÃm contribuÃdo para o aumento das concentraÃÃes de metais pesados nos diversos tipos de solo. Tais elementos apresentam relevante toxicidade e podem se acumular no ambiente, configurando sÃrio risco à saÃde humana e dos ecossistemas em geral. Nesse cenÃrio, percebe-se uma preocupaÃÃo crescente dos paÃses em adotar uma polÃtica ambiental eficiente e, dessa forma, a determinaÃÃo da concentraÃÃo natural (nÃveis de background) de metais nos solos e o estabelecimento de valores de referÃncia de qualidade (VRQs) jà sÃo realidade em alguns paÃses, inclusive no Brasil. Entretanto, percebe-se a escassez de estudos dessa natureza que contemplem os solos sob florestas de mangue no paÃs, onde tais Ãreas sÃo bastante expressivas e desempenham importantes funÃÃes e serviÃos no ambiente. Nesse contexto, a contaminaÃÃo dos solos de mangue por metais pesados à uma das grandes questÃes ambientais da atualidade, podendo, inclusive, comprometer os estuÃrios em toda a sua extensÃo. Assim, foi realizado um estudo em solos de mangue do Estado do Cearà visando a classificaÃÃo e caracterizaÃÃo dos mesmos, alÃm da determinaÃÃo dos teores naturais de metais e a consequente proposiÃÃo de seus VRQs. Para isso, foram realizadas anÃlises fÃsicas, quÃmicas e mineralÃgicas, extraÃÃo dos metais por mÃtodos de digestÃo semitotal (EPA 3051A e Ãgua rÃgia) e a determinaÃÃo dos VRQs foi realizada de acordo com o disposto na resoluÃÃo n 420/2009 do CONAMA. Os resultados obtidos indicaram que o clima predominantemente semiÃrido da regiÃo explica o comportamento dos principais atributos desses solos (ex: CE, COT, constituiÃÃo mineralÃgica). Verificou-se ainda que os teores de metais nos solos em questÃo sÃo influenciados pela intensidade da interferÃncia antropogÃnica nos ambientes costeiros, tendo em vista que os solos de mangue do estuÃrio do rio CearÃ, inserido em contexto urbano e submetido a diversos tipos de tensÃes ambientais, apresentaram os maiores fatores de enriquecimento de metais. Por outro lado, observou-se que a distribuiÃÃo de tais elementos nesses solos à tambÃm regida por interaÃÃes entre os prÃprios metais e dos mesmos com atributos como a fraÃÃo argila e os Ãxidos de Fe e Mn. AlÃm disso, a digestÃo por Ãgua rÃgia mostrou-se eficiente na extraÃÃo de metais nesses solos, enquanto o EPA 3051A, indicado pelo CONAMA para avaliaÃÃes de qualidade dos solos, subestimou os teores dos metais disponÃveis nos mesmos. Diante do exposto, os teores naturais dos metais determinados no presente estudo podem servir de base para a definiÃÃo de VRQs para os solos de mangue do Estado do CearÃ, auxiliando o ÃrgÃo ambiental responsÃvel na formulaÃÃo de uma legislaÃÃo especÃfica para o monitoramento das Ãreas de manguezal do Estado, configurando, portanto, uma nova perspectiva para a gestÃo dos ambientes estuarinos.
132

Gestão da zona costeira: políticas públicas e atores sociais na praia da Cocanha, Caraguatatuba, São Paulo / Coastal zone management: public policy and stakeholders in Cocanhas beach, Caraguatatuba, São Paulo

Jussara Shirazawa de Freitas 18 September 2012 (has links)
A zona costeira é um amplo espaço de interação onde a dinâmica ambiental afeta as complexas relações entre o homem e o meio. Essa região é formada por um mosaico de importantes ecossistemas, que apresentam alta biodiversidade e complexidade, e cuja diversidade é marcada pela transição de ambientes terrestres e marinhos, com interações que lhe conferem caráter de fragilidade requerendo atenção especial do poder público. Observa-se nessa região quadros problemáticos do ponto de vista da gestão ambiental, demandando ações de caráter corretivo, com a mediação dos múltiplos conflitos de usos dos espaços e recursos comuns e de controle do impacto sobre os ambientes marinhos. Uma ferramenta muito importante para que se atinja o equilíbrio entre as atividades na zona costeira e a conservação ambiental é o Gerenciamento Costeiro Integrado (GCI). Este é definido como um conjunto de atividades e procedimentos que permite a gestão dos recursos naturais de forma participativa, objetivando a melhoria da qualidade de vida das populações locais, a conservação da fauna e da flora e a adequação das atividades humanas à capacidade de suporte dos ecossistemas. Uma das ferramentas, no contexto do GCI, é a Avaliação de Políticas Públicas. Esta tem por objetivo fazer com que os resultados e os conhecimentos produzidos pela avaliação resultem na construção de valores para que governantes e população obtenham referências sobre quais fatores determinaram o sucesso ou insucesso de uma ação e possam, então, interferir nos processos e corrigir e/ou propor novas políticas. O presente trabalho tem como objetivo compreender como a implementação de políticas públicas na Praia da Cocanha influenciou a dinâmica das redes sociais e contribuiu para a construção socioespacial. A área de estudo configura-se como excelente exemplo das questões e dos problemas do Litoral Norte do Estado de São Paulo e da região costeira brasileira. A avaliação da construção socioespacial da região e dos efeitos das ações governamentais implementadas sobre o território foi feita com base no modelo teórico de Avaliação de Políticas Públicas. Para fazer a avaliação, foram feitas entrevistas com pessoas que sofreram a ação direta das políticas (membros da comunidade), bem como pessoas que estão ligadas diretamente com a região de estudo (atores externos, como pesquisadores). O que observamos na Praia da Cocanha é que a população local não participou efetivamente e ativamente das políticas públicas implementadas na região. As políticas, apesar de impactos positivos como a geração de empregos e renda para a comunidade, foram mal planejadas e implementadas, ocasionando problemas para a comunidade e degradação ambiental. A realidade local da Praia da Cocanha é um reflexo do que ocorre no município de Caraguatatuba e em muitos outros do País. A falta de planejamento está prejudicando a população e permitindo que haja comprometimento do meio ambiente. / The coastal zone is a broad area of interactions where the environmental dynamics affect the complex relation between man and the surrounding environment. The landscape is formed by a mosaic of highly biodiverse and complex ecosystems, marked by the terrestrial-marine transition and its interactions, what gives it a character of fragility which requires special attention from policy makers. There is a series of problematic issues concerning environmental management practices. Thus, demanding corrective actions such as mediating multiple conflicts in use of space and resources, and controlling the impact on the marine environment. A very important tool to achieve the balance between human activities in the coastal zone and environmental conservation is the Coastal Zone Management (CZM), that can be defined as a set of activities and procedures that enables the management of natural resources in a participatory way, improving the communitys life quality, the conservation of fauna and flora, and the adequacy of human activities to the ecosystems support capacity. One of the tools, in the context of the CZM, is the Evaluation of Public Policies. The present study aims to understand how the implementation of public policies in Cocanha Beach influenced the dynamics of social networks, and contributed to the socio-spatial setting. The study site is considered an excellent example of common issues and problems along the northern coast of São Paulo State, as well along the Brazilian coast. The evaluation of the socio-spatial setting and the effects of implemented government actions on the territory were based on Evaluation of Public Policies theoretical model. In order to the evaluation to be done, several stakeholders were interviewed, such as those who have suffered direct effects of policies (community members), and others who are directly connected with the study site (external actors such as researchers). By the end of the evaluation, it was possible to observe that the local community did not effectively or actively participate in the public policies implemented in the region. Despite the job and income generation among the community, the implemented policies were poorly planned and executed, causing problematic arrangements for the community, as well as environmental degradation. The reality of Cocanha Beach a glimpse of what occurs in the City of Caraguatatuba, and in many other Brazilian coastal cities. The lack of responsible planning is affecting the population and compromising the environment.
133

Systematic marine spatial planning and monitoring in a data poor environment: a case study of Algoa Bay, South Africa

Chalmers, Russell January 2012 (has links)
Globally the failure of traditional fisheries management approaches is evident through the increasing number of overexploited or depleted marine stocks. Past sectoral management has failed to address cumulative impacts of fisheries activities on ecosystem health. Ecosystem based approaches have been advocated as a viable alternative for sustainable management of marine ecosystems as they present a holistic and precautionary approach, which integrates management of multiple activities with that of maintaining ecological health. Although conceptually advanced, implementation has been poor due to the complexities of competing ecological and socio-economic management objectives. Marine spatial planning can facilitate the implementation of ecosystem based management as it is able to address the spatial heterogeneity of biological communities and anthropogenic activities. Ecosystem based management approaches aim to address the full range of anthropogenic drivers on the marine environment, including but not limited to fisheries, tourism, coastal development, and land and marine based pollution sources amongst others. Fisheries activities have a direct impact on the local marine environment and were therefore the focus of this study which forms a starting point for implementing ecosystem based management in Algoa Bay. It is envisaged that future research will build on this foundation and include additional anthropogenic drivers into the management and monitoring strategies developed in this study in order to achieve a truly holistic ecosystem approach to management in Algoa Bay. Algoa Bay is situated centrally within the warm-temperate Agulhas bioregion along the east coast of South Africa and is the largest and best formed logarithmic spiral bay along this section of coastline. A large city, two commercial ports and several coastal settlements are located within Algoa Bay and a wide range of marine based activities occur within the area. A large section of the coastline is proclaimed as a National Park yet only two small offshore marine areas are formally protected. The development of a large marine protected area (MPA) adjoining the terrestrial section was proposed in the mid-1990s but a lack of adequate spatial data with which to quantify the fishery costs and conservation benefits led to wide scale public opposition and halted the declaration process. The primary goal of this study was to obtain and analyse baseline data to understand spatial and temporal trends in the distribution and abundance of fish populations and fisheries activities in order to develop a spatial framework for marine conservation and management in a data limited situation using Algoa Bay, South Africa as a case study. Furthermore, it aims to contribute to the development of a monitoring framework to evaluate the success of implementation and the resultant changes in biological and socio-economic environments. This information will be used to re-initiate the stakeholder engagement process in the future.
134

An examination of the role of local government in coastal zone management: the case of Richmond, B.C.

Pernu, James Victor 11 1900 (has links)
The management of the coastal zone is a complex task facing all three levels of Canadian Government. While academic research and public attention tend to focus on federal and provincial agencies, the role of local government has been left largely unexplored. This thesis examines the role of local government in coastal zone management in British Columbia and evaluates local government’s contribution to the management of the coastal zone based on the performance of local planning policies in the coastal community of Richmond, B.C. Coastal zone management (C.Z.M.) is a specialized subset of contemporary resource management models having three hierarchically integrated components representing biophysical, socio-economic and institutional subsystems. A literature review yielded many management issues of which seven were selected to reflect the local government experience in C.Z.M. The seven issues are: Habitat Conservation, Water Quality, Coastal Hazards, Public Access and Aesthetics, Public Input, Water Dependency and Interjurisdictional Coordination. The evaluation of Richmond’s C.Z.M. policies was undertaken using a methodology similar to those employed by Rosentraub (1975) and Jessen et al. (1983). A retrospective analysis of Development Permit Application files processed between 1988 and 1991 was employed in the evaluation of existing policies contained within Richmond’s Official Community Plan. While the exact extent of local responsibilities remains poorly defined by existing legislation, local regulatory powers in C.Z.M. were determined to be nonetheless significant. The British Columbia Municipal Act provided a considerable amount of regulatory authority for each of the seven coastal zone management issues, namely in the form of Zoning bylaws, Official Community Plan bylaws and Development Permits. The findings indicate that Richmond’s existing policies displayed limited effectiveness concerning the management of C.Z.M. issues such as Habitat Conservation, Water Quality, Coastal Hazards and Interjurisdictional Coordination. However, the results also suggested that local policies addressing coastal zone issues such as public access and aesthetics were effective. Furthermore, explicit policies for Water Dependency and Public Input were non existent. Several recommendations were made in this thesis. The first is an expanded recognition of C.Z.M. as a local government concern and responsibility. Further recommendations include increased interjurisdictional involvement, greater public access to waterfront surrounding industrial sites and discouraging the pressure to develop in the floodplain. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
135

A proposed approach to the formulation of an integrated coastal zone management policy for the Erongo zone in Namibia

Gxaba, Lungiswa Thandiwe January 1996 (has links)
Bibliography: pages 89-92. / As a follow-up to the United Nations Conference on Environment and Development (UNCED) which was held in Rio de Janeiro in 1992, the Danish Co-operation for Environment and Development (DANCED) was established in 1993. DANCED was established with the overall objective of contributing to the restoration of the global environment in accordance with the recommendations of Agenda 21. The DANCED programme is managed by the Danish Ministry of Foreign Affairs. To support the DANCED programme in the Southern African region, a DANCED office has been established at the Royal Danish Embassy in Pretoria. In the Southern African region, activities were initiated in 1995 with South Africa, Namibia and Botswana as target countries. In February 1995, a DANCED programme formulation mission assessed institutional and organisational issues in relation to the future DANCED programme in Namibia. During this process, the Ministry of Fisheries and Marine Resources (MFMR) requested assistance from DANCED with an environmental management plan for Walvis Bay and surrounding areas. This concept fitted with DANCED's identification of integrated coastal zone management (ICZM) as one of its key areas of support. After discussions with the Ministry of Environment and Tourism (MET), and other key stakeholders, the project proposal was broadened into developing an integrated management plan for the Erongo coastal zone in Namibia. The mission for this project was carried out from September to November 1995. In November 1995, DANCED contracted the 1995/96 masters students from the Environmental and Geographical Sciences Department, at the University of Cape Town, to collect baseline information which would contribute to the development of an ICZM plan for the Erongo coastal zone in Namibia. 'Ibis exercise was initiated in November 1995. Information was gathered, synthesised and compiled into a baseline report which was submitted to DANCED at the end of March 1996. This dissertation focuses particularly on the policy aspects of an ICZM plan and draws on the information contained in the baseline report.
136

MODELING GROUND ELEVATION OF LOUISIANA COASTAL WETLANDS AND ANALYZING RELATIVE SEA LEVEL RISE INUNDATION USING RSET-MH AND LIDAR MEASUREMENTS

Unknown Date (has links)
The Louisiana coastal ecosystem is experiencing increasing threats from human flood control construction, sea-level rise (SLR), and subsidence. Louisiana lost about 4,833 km2 of coastal wetlands from 1932 to 2016, and concern exists whether remaining wetlands will persist while facing the highest rate of relative sea-level rise (RSLR) in the world. Restoration aimed at rehabilitating the ongoing and future disturbances is currently underway through the implementation of the Coastal Wetlands Planning Protection and Restoration Act of 1990 (CWPPRA). To effectively monitor the progress of projects in CWPPRA, the Coastwide Reference Monitoring System (CRMS) was established in 2006. To date, more than a decade of valuable coastal, environmental, and ground elevation data have been collected and archived. This dataset offers a unique opportunity to evaluate the wetland ground elevation dynamics by linking the Rod Surface Elevation Table (RSET) measurements with environmental variables like water salinity and biophysical variables like canopy coverage. This dissertation research examined the effects of the environmental and biophysical variables on wetland terrain elevation by developing innovative machine learning based models to quantify the contribution of each factor using the CRMS collected dataset. Three modern machine learning algorithms, including Random Forest (RF), Support Vector Machine (SVM), and Artificial Neural Network (ANN), were assessed and cross-compared with the commonly used Multiple Linear Regression (MLR). The results showed that RF had the best performance in modeling ground elevation with Root Mean Square Error (RMSE) of 10.8 cm and coefficient of coefficient (r) = 0.74. The top four factors contributing to ground elevation are the distance from monitoring station to closest water source, water salinity, water elevation, and dominant vegetation height. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
137

L'environnement "révolutionnaire" : pratiques, discours et dynamique socio-environnementale de la gestion des ressources côtières à Cuba

Doyon, Sabrina January 2003 (has links)
No description available.
138

Ecologically sustainable coastal management: A legal blueprint

Macdonald, Roslyn January 2003 (has links)
The theme of this thesis is that ecologically sustainable coastal management (ESCM) is achievable through the application of law. Once the legal principles and the administrative structures that that law supports have been put into place a framework is created within which the goal of ecologically sustainable development - 'Development that improves the total quality of life, both now and in the future, in a way that maintains the ecological processes on which life depends' can be realised. This thesis approaches the task by analysing the components of ecologically sustainable development (ESD), synthesising them into a set of principles for achieving ESCM and then, by using a comparative approach, devising a number of recommendations, which, if followed, will enable ESCM to be achieved. While the focus is on ESCM, the recommendations could be applied with minimal adaptation, to most, if not all, natural resource management. The thesis is divided into five Parts. Part A looks at the function of law in ESCM and proposes a theoretical model for a legal and administrative regime to be tested in the remaining Parts. Part B considers the context for ESCM and the policies and approaches followed by the different jurisdictions compared throughout this thesis, in addressing sustainable development, with emphasis in chapter four on devising the principles for ESCM. These principles are then developed and analysed in the remaining Parts of the thesis. Part C looks at the current constitutional legal regime for the coastal zone in each jurisdiction and then moves on to consider the first two of the principles for ESCM, international responsibilities and integrated coastal zone management, linked together in this part by the direct dependence on law as the agent for management Part D is about the four remaining principles of ESCM - the practical instruments for achieving ESCM. These are environmental impact assessment, public participation, coastal planning and economic instruments. In the last Part, Part E, the suggested principles for ESCM are brought together and, by a comparison of the various legal and administrative mechanisms used in the jurisdictions reviewed in this thesis, recommendations for achieving ESCM are drawn up. It is suggested that implementation of these recommendations will achieve ecologically sustainable coastal management.
139

Marine protected areas in Hong Kong: present status and future management challenges

Lui, Fong-fong., 雷芳芳. January 1999 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
140

Challenging prospects for marine conservation and coastal zone management in Hong Kong

Ng, Lai-ha., 吳麗霞. January 1999 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

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