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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.
141

Scenario Development and Analysis of Freshwater Ecosystem Services under Land Cover and Climate Change in the Tualatin and Yamhill River Basins, Oregon

Hoyer, Robert Wesley 13 December 2013 (has links)
Humans make decisions within ecosystems to enhance their well-being, but choices can lead to unintended consequences. The ecosystem services (ES) approach supports decision-making that considers all environmental goods and services. Many challenges remain in the implementation of the ES approach like how specific ES vary through space and time. We address this research problem using the Tualatin and Yamhill river basins in northwestern Oregon as a study area. Freshwater ES are quantified and mapped with the spatially-explicit ES modeling tool, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST). In chapter II, we develop a simple urban land cover change modeling approach with selected stakeholder input. The products of this analysis are used in part to answer the question of how the freshwater ES of water yield, nutrient retention, and sediment retention will change in the future, and how their distribution potentially will change? In chapter III, these ES are modeled in InVEST using the land cover scenarios and three downscaled global climate models. The base period is 1981 to 2010 and the future period is 2036 to 2065. The models are calibrated to empirical estimates, and display different sensitivities to inputs. Water yield increases with higher rainfall but decreases with the highest temperature scenario. Nutrient export and retention estimates are positively correlated. In the Tualatin basin, more urban lands generally lead to increases in nutrient exports and retention. The effect is reversed in the Yamhill basin from much larger agricultural exports. Sediment exports and retention increase with higher winter rainfall but are negatively spatially correlated due to topographic effects. Simulation of a landscape scale installation of riparian buffers leads to decreases in exports and increases in retention. The distribution of the provision of freshwater ES remains unchanged throughout the scenarios. With few parameters in each InVEST model, all display a high degree of sensitivity. Parameterization is subject to high uncertainty even with calibrated values. We discuss the assumptions and limitations of InVEST's freshwater models. The spatially explicit nature of InVEST is its main advantage. This work coupled with other analyses in the study area can facilitate the identification of tradeoffs amongst ES leading to better ecosystem management.
142

Developing integrated management of ephemeral river basins in Botswana : the case of Boteti river sub-basin

Motsholapheko, Moseki Ronald 04 1900 (has links)
Botswana is a water scarce country. Rainfall is highly variable, leading to limited surface and groundwater resources. Due to persistently dry conditions most rivers found in Botswana are ephemeral. The Boteti River sub-Basin is one of the numerous ephemeral river sub-Basins, in Botswana. Key environmental challenges, resulting from human activities, in the sub-Basin are: increased pressure on local resources due to overstocking, overgrazing and over-harvesting; reductions in wildlife numbers; denudation of vegetation and the resultant exposure of the soil to wind erosion. As a major step, to pilot implementation of river basin management in the ephemeral river basins in southern Africa, the Boteti River sub-Basin is one of the key areas identified for study under the Ephemeral River Basins in the Southern African Development Community SADC (ERBSADC) Project. This study was initiated, as part of the ERB-SADC project and its aim is to investigate the socio-economic status of the Boteti River sub-Basin and determine the potential for developing integrated management of water and land resources in the sub- Basin. Its key objectives are to identify and assess types and patterns of water use; to identify and assess key livelihood activities; and to critically assess community participation in water resources management in the sub-Basin. A questionnaire was administered to 293 households, a focus group discussion was held with twelve community representatives of six villages in the sub-Basin, six traditional leaders and five local government officers were interviewed as key informants, and informal discussions were held with three local farmers. Results from the study indicate low livelihood levels based on livestock and arable agriculture, high dependence on natural resources and low participation of communities in water management. The study concludes that a livelihood approach to integrated water resources management can help deal with environmental challenges and enhance community participation. / Environmental Sciences / Thesis (M.A. (Environmental Science))
143

Developing integrated management of ephemeral river basins in Botswana : the case of Boteti river sub-basin

Motsholapheko, Moseki Ronald 04 1900 (has links)
Botswana is a water scarce country. Rainfall is highly variable, leading to limited surface and groundwater resources. Due to persistently dry conditions most rivers found in Botswana are ephemeral. The Boteti River sub-Basin is one of the numerous ephemeral river sub-Basins, in Botswana. Key environmental challenges, resulting from human activities, in the sub-Basin are: increased pressure on local resources due to overstocking, overgrazing and over-harvesting; reductions in wildlife numbers; denudation of vegetation and the resultant exposure of the soil to wind erosion. As a major step, to pilot implementation of river basin management in the ephemeral river basins in southern Africa, the Boteti River sub-Basin is one of the key areas identified for study under the Ephemeral River Basins in the Southern African Development Community SADC (ERBSADC) Project. This study was initiated, as part of the ERB-SADC project and its aim is to investigate the socio-economic status of the Boteti River sub-Basin and determine the potential for developing integrated management of water and land resources in the sub- Basin. Its key objectives are to identify and assess types and patterns of water use; to identify and assess key livelihood activities; and to critically assess community participation in water resources management in the sub-Basin. A questionnaire was administered to 293 households, a focus group discussion was held with twelve community representatives of six villages in the sub-Basin, six traditional leaders and five local government officers were interviewed as key informants, and informal discussions were held with three local farmers. Results from the study indicate low livelihood levels based on livestock and arable agriculture, high dependence on natural resources and low participation of communities in water management. The study concludes that a livelihood approach to integrated water resources management can help deal with environmental challenges and enhance community participation. / Environmental Sciences / Thesis (M.A. (Environmental Science))
144

Anthropocentric impacts on the ecology and biodiversity of the Natalspruit watercourse and its associated wetlands

Kruger-Franck, Elmarie 07 1900 (has links)
Information regarding the ecological wellbeing of the Natalspruit and its adjoining wetlands is essential if the river is being managed using sound ecological management principles. Despite this, little is known about this river, with little documentation at the regional or municipal level. This study partially addresses this knowledge gap by evaluating the impacts of human activity on a section of the Natalspruit and its adjoining wetlands. It reports on pollution concentrations found at selected sample sites and compares the results to Rand Water data and the National Standards and Guidelines of South Africa for physicochemical parameters and contaminated soils. Water samples were collected at five chosen sample sites during May and July 2018. Soil samples were taken during July 2018. The study found that water at all five sample sites is not suitable for drinking, the health of livestock and recreational use due to the present and high Total Coliform levels (ranging from 450 CFU/100ml to 100 000 CFU/100ml), as well as Turbidity, Total Hardness, TDS, Mg, NO2, SO4, and BOD which also exceeded the guidelines. Only site SS1 (May) exceeded the CaCO3 concentrations regarding livestock health. No guidelines were available for DO levels on the health of livestock. Cl levels in the Natalspruit was suitable for drinking. PO4 concentration at all the sites were all within the guidelines of acceptable levels for aquatic ecosystems. In terms of heavy metals, Cr levels significantly exceeded the guidelines at all five sample sites with the exception of ecosystem health. This is of great concern due to the toxicity of Cr. Cu concentrations exceeded the guidelines for both all land-uses protective of water resources and ecosystem health, at SS1, SS2, SS3 and SS5. Ni concentrations exceeded the guidelines for all land-uses protective of the water resources at SS5. Pb and Zn concentrations exceeded the guidelines for the land-uses protective of the water resources at all the sites with the exception of SS4 for Pb and SS2 and SS4. SS1 and SS5 reported Zn concentrations higher than the guideline for the protection of ecosystem health. SASS 5, PES and EIS assessments indicated moderate to severe modifications of the river. Thus, mining, industrial activities, surface runoff from densely populated informal settlements and wastewater treatment plants have negatively impacted upon the river. Decades of environmental neglect and effluent discharge have degraded the ecosystem, thus necessitating rehabilitation. However, as the study was limited in both time and scope, so additional research should be undertaken. / Environmental Sciences / M. Sc. (Environmental Management)
145

Conservação da biodiversidade, cultivo e produção de erva-mate no município de São Mateus do Sul - Paraná / Biodiversity conservation, cultivation and production of yerba-mate in the municipality of São Mateus do Sul - PR

Luiz, Ricardo Gomes 15 December 2017 (has links)
A conservação da biodiversidade é objeto de um acordo internacional promovido pela Organização das Nações Unidas (ONU), a qual registra a redução da diversidade de espécies e ecossistemas em todo o Planeta. O Brasil é signatário da Convenção sobre Diversidade Biológica desde 1994. Sua responsabilidade se estende por biomas como a Amazônia, Pantanal, Cerrado, Caatinga, Campos Sulinos e a Mata Atlântica, além das áreas marinhas. Esta dissertação está inserida no contexto da Floresta com Araucária, situada no sul do Brasil. Associada à Mata Atlântica, ali ocorrem árvores pinheiros, imbuias, ipês, canelas e a erva-mate, além de uma variada fauna. Em processo de trocas de áreas de floresta por áreas de cultivo, há necessidade de se criar estratégias para conservar as áreas remanescentes, como é o caso daquelas existentes no município de São Mateus do Sul-PR. As argumentações para embasar este contexto de perda de biodiversidade e das externalidades provêm dos estudos de Ciência, Tecnologia e Sociedade, os quais desenvolvem conceitos relevantes para estabelecer as relações entre as ações humanas e a manutenção da biodiversidade. O objetivo geral do estudo é analisar os conflitos, as contradições e consensos que interferem na conservação da diversidade biológica e nas formas de cultivo da ervamate produzida no município de São Mateus do Sul-PR. A pesquisa é de natureza qualitativa, descritiva e bibliográfica. Os procedimentos metodológicos recorrem à análise da percepção e coleta de dados por meio de observação, entrevistas e depoimentos. Na perspectiva da conservação da biodiversidade da Floresta com Araucária com a qualidade do produto da erva-mate cultivado na região, com base em comportamentos conflituosos e contraditórios, empresas e produtores fizeram associações técnicas e científicas não satisfatórias para as expectativas da dissertação. Porém, existem contribuições e potencialidades de acordos e consensos dos atores e de conceitos dos estudos CTS que permitiram criar diferentes olhares para o pesquisador sobre seu objeto de estudo. Logo, o levantamento e análise de dados foram veículos de abertura para adentrar em ponderações entre sobrevivência e respeito ao meio ambiente. Deste modo, conclui-se que existe continuamente uma construção social dos atores que pode trazer à tona outros conceitos que contrastam com o determinismo e a utopia dos ganhos e perdas. / The conservation of biodiversity is an issue of an international agreement promoted by the United Nations, which records the reduction of diversity of species and ecosystems throughout the planet. Brazil has been a signatory to the Convention on Biological Diversity since 1994. Its responsibility extends to biomes such as the Amazon, Pantanal, Cerrado, Caatinga, Campos Sulinos and the Atlantic Forest, in addition to marine areas. This dissertation is inserted in the context of the Araucaria Forest, located in the south of Brazil. Associated with the Atlantic Forest, in this ecosystem there are trees like araucaria-pine, imbuias, ipês, canelas and yerba-mate, besides a varied fauna. In the process of exchanging forest for cultivated areas, it is necessary to create strategies to conserve the remaining areas, as is the case of those existing in the municipality of São Mateus do Sul, in Paraná State. The arguments to support this context of loss of biodiversity and externalities come from the Science, Technology and Society (STS) studies, which develop relevant concepts to establish the relations between human actions and the maintenance of biodiversity. The general objective of the study is to analyze the conflicts, contradictions and consensuses that interfere in the conservation of the biological diversity and in the forms of cultivation of yerba mate produced in the municipality of São Mateus do Sul. The research is qualitative, descriptive and bibliographic. The methodological procedures use the analysis of perception and data collection through observation, interviews and testimonials. In the perspective of the conservation of the biodiversity of the Araucaria Forest with the quality of the yerba-mate cultivated in the region, based on conflicting and contradictory behaviors, companies and producers made technical and scientific associations not satisfactory to the expectations of the dissertation. However, there are contributions and potentialities of agreements and consensus of the actors and concepts of the STS studies that allowed to create different looks for the researcher about his object of study. Therefore, the data collection and analysis were opening fields to enter into considerations between survival and respect for the environment. In this way, it is concluded that there is a continuous social construction of actors that can bring to light other concepts that contrast with the determinism and utopia of gains and losses.
146

A review of lessons learned to inform capacity-building for sustainable nature-based tourism development in the European Union funded ʺSupport to the Wild Coast Spatial Development Initiative Pilot Programmeʺ

Wright, Brian Bradley January 2006 (has links)
This case-study establishes the influences of power-knowledge relationships on capacity-building for sustainability in the European Union Funded ‘Wild Coast Spatial Development Initiative Pilot Programme’ (EU Programme). It aims to capture the lessons learned for capacitybuilding to support nature-based tourism initiatives on the Wild Coast. The EU Programme aimed to achieve economic and social development of previously disadvantaged communities through nature-based tourism enterprises, and to develop capacity of local authorities and communities to support environmental management. The study discusses common trends in thematic categories emerging from the research data, and contextualises research findings in a broader development landscape. This study indicates that power-knowledge relations were reflected in the EU Programme’s development ideology by an exclusionary development approach, which lacked a participatory ethos. This exclusionary approach did not support an enabling environment for capacity-building. This development approach, guiding the programme conceptualization, design and implementation processes, resulted in a programme with unrealistic objectives, time-frames and resource allocations; a programme resisted by provincial and local government. The study provides a causal link between participation, programme relevance, programme ownership, commitment of stakeholders, effective management and capacity-building for sustainable programme implementation. The study argues that the underlying motivation for the exclusionary EU development ideology in the programme is driven by a risk management strategy. This approach allows the EU to hold power in the development process, whereas, an inclusionary participative development methodology would require a more in-depth negotiation with stakeholders, thereby requiring the EU to relinquish existing levels of power and control. This may increase the risk of an unexpected programme design outcome and associated exposure to financial risk. It may also have a significant financial effect on donor countries' consultancies and consultants currently driving the development industry. This study recommends an interactive-participative methodology for programme design and implementation, if an enabling environment for capacity-building is to be created. In addition, all programme stakeholders must share contractual accountability for programme outcomes. This requires a paradigm shift in the EU development ideology to an inclusionary methodology. However, this research suggests that the current EU development approach will not voluntarily change. I, therefore, argue that South Africa needs to develop a legislative framework that will guide donor-funded development programme methodology, to support an enabling environment for capacity-building.
147

User Modeling and Optimization for Environmental Planning System Design

Singh, Vidya Bhushan January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Environmental planning is very cumbersome work for environmentalists, government agencies like USDA and NRCS, and farmers. There are a number of conflicts and issues involved in such a decision making process. This research is based on the work to provide a common platform for environmental planning called WRESTORE (Watershed Restoration using Spatio-Temporal Optimization of Resources). We have designed a system that can be used to provide the best management practices for environmental planning. A distributed system was designed to combine high performance computing power of clusters/supercomputers in running various environmental model simulations. The system is designed to be a multi-user system just like a multi-user operating system. A number of stakeholders can log-on and run environmental model simulations simultaneously, seamlessly collaborate, and make collective judgments by visualizing their landscapes. In the research, we identified challenges in running such a system and proposed various solutions. One challenge was the lack of fast optimization algorithm. In our research, several algorithms are utilized such as Genetic Algorithm (GA) and Learning Automaton (LA). However, the criticism is that LA has a slow rate of convergence and that both LA and GA have the problem of getting stuck in local optima. We tried to solve the multi-objective problems using LA in batch mode to make the learning faster and accurate. The problems where the evaluation of the fitness functions for optimization is a bottleneck, like running environmental model simulation, evaluation of a number of such models in parallel can give considerable speed-up. In the multi-objective LA, different weight pair solutions were evaluated independently. We created their parallel versions to make them practically faster in computation. Additionally, we extended the parallelism concept with the batch mode learning. Another challenge we faced was in User Modeling. There are a number of User Modeling techniques available. Selection of the best user modeling technique is a hard problem. In this research, we modeled user's preferences and search criteria using an ANN (Artificial Neural Network). Training an ANN with limited data is not always feasible. There are many situations where a simple modeling technique works better if the learning data set is small. We formulated ways to fine tune the ANN in case of limited data and also introduced the concept of Deep Learning in User Modeling for environmental planning system.
148

The Link Between Smart Growth in Urban Development and Climate Change

Mathew, Brenda A. 22 January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI)

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