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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.
461

Identificação e valoração sociocultural dos serviços ecossistêmicos - o caso da comunidade de Marujá, Ilha do Cardoso - SP, Brasil / Socio-cultural identification and valuation of ecosystem services the case of Marujá community, Cardoso Island SP, Brazil

Daminello, Camila Jericó 05 December 2014 (has links)
A intensa relação entre sistema econômico e ambiental é tema de discussões e análises de diversas áreas de estudo, mas foi com o surgimento da Economia Ambiental e, posteriormente, da Economia Ecológica que este tópico teve o seu destaque. Mesmo com diferenças substanciais ambas as áreas têm como um dos seus objetivos a identificação e quantificação dos recursos e processos naturais que apresentam utilidade humana, chamados atualmente de serviços ecossistêmicos, através da técnica de valoração ambiental. Dependendo de seu enfoque, a valoração ambiental pode apresentar cálculos e concepções diferentes. Basicamente, existem três esferas de valor dos serviços ecossistêmicos: a econômica, a ecológica e a sociocultural. Por questões metodológicas, de definição e, principalmente, de relutância em discutir questões socioculturais, a última esfera se apresenta pouco desenvolvida e aplicada. A motivação de modificar este quadro se encontra na busca de um melhor entendimento dos diferentes usos dos serviços ecossistêmicos, com destaque para os chamados serviços ecossistêmicos culturais, a fim de uma tomada de decisão que se baseie nas três esferas de valor. Assim, com o objetivo de contribuir para o desenvolvimento da faceta sociocultural da valoração dos serviços ecossistêmicos, o presente estudo foi construído. Para isso, foi proposta e testada uma nova metodologia que permite a identificação (Free listing) e valoração sociocultural (Índice de Saliência de Smith) dos serviços ecossistêmicos através das respostas de comunitários quando submetidos a um questionário semi-estruturado específico. O estudo foi conduzido na Comunidade do Marujá, situada na Ilha do Cardoso, litoral sul do Estado de São Paulo. No total, 53 moradores tradicionais (representando 88% das famílias) foram questionados sobre suas relações, utilitárias, pessoais e comunitárias, com o ecossistema de praia que ladeia a comunidade. Ao todo, 18 serviços ecossistêmicos foram identificados, alguns descritos pela primeira vez, e classificados em três categorias, uma delas também criada neste estudo. Numa análise geral, Alimento, Trabalho e serviços ecossistêmicos culturais, como Identidade de Lugar apresentam os valores mais altos. A utilização de Free listing em conjunto com o Índice de Saliência de Smith se mostrou uma metodologia interessante para a identificação e valoração dos serviços ecossistêmicos a partir do envolvimento de uma população local. Seus resultados são consistentes e permitem a comparação com outros estudos, além de poderem ser utilizados, juntamente com valores de outras esferas, para a composição de um quadro mais completo de tomada de decisão. / The intense relationship between economic and environmental systems has been discussed and analyzed in several areas of study, but it was with the advent of Environmental Economics and, subsequently, the Ecological Economics that this topic had its prominence. Even with substantial differences, both areas have as common objective, the identification and quantification of natural resources and processes that have human utility, also known as ecosystem services. This can be done by environmental valuation techniques. Depending on its approach, environmental valuation has different outcomes, methods and concepts. In general, there are three spheres of ecosystem services values: the economic, the ecological and the socio-cultural one. Because of methodological limitations, definition problems and, mainly, the reluctance in discussing cultural issues, the last sphere is poorly developed and applied. The motivation for modifying this situation is the search for a better understanding of ecosystem services\' different uses, with emphasis on the so-called cultural ecosystem services in order to take decisions that are based on the three spheres of value. Thus, with the objective of contributing to the development of the cultural sphere of ecosystem services valuation, the present study was constructed. A new methodology was therefore proposed and tested: this methodology allows the identification (Free-listing) and sociocultural valuation (Smiths Salience Index) of ecosystem services through the response of a community when submitted to a semi-structured questionnaire. The study was conducted in Marujá community, situated on the Cardoso Island, south coast of Sao Paulo State. In total, 53 traditional residents (representing 88% of households) were asked about their relationship, utilitarian, personal and community, with the community beach ecosystem. In all, 18 ecosystem services were identified. Some were described for the first time, and classified into three categories, one of which was also first assessed in this study. In a general analysis, \"Food\", \"Job\" and cultural ecosystem services, such as \"Sense of place\" have the highest values. The use of Free-listing in conjunction with the Smiths Salience Index appeared to be an interesting methodology for the purpose of identification and valuation of ecosystem services through local population. The results are consistent and allow comparison with other studies. In addition, it can be used together with other sphere values in order to compose a more complete framework for decision-making purpose.
462

A comparison of pixel based and object based vegetation community classification in the Arthur R. Marshall Loxahatchee National Wildlife Refuge

Unknown Date (has links)
Pixel based and object based vegetation community classification methods were performed using 30 meter spatial resolution Landsat satellite imagery of the Arthur R. Marshall Loxahatchee National Wildlife Refuge (Refuge), a remnant of the northern Everglades. Supervised classification procedures using maximum likelihood and parallelepiped algorithms were used to produce thematic maps with the following vegetation communities : wet prairie, sawgrass, cattail, tree island, brush, aquatic/open water. Spectral data, as well as NDVI, texture and principal component data were used to produce vegetation community classification maps. The accuracy levels of the thematic maps produced were calculated and compared to one another. The pixel based approach using the parallelepiped classification algorithm on the spectral and NDVI dataset had the highest accuracy level. A generalized form of this classification using only three vegetation communities (all wet prairie, tree island/brush and aquatic/open water) was compared to a previously published classification which used 1987 SPOT imagery in order to extract information on possible vegetation community transitions that are occurring within the Refuge. Results of the study indicate that 30 meter spatial resolution may be useful for understanding broad vegetation community trends but not species level trends. Pixel based procedures provide a more accurate classification than object based procedures for this landscape when using 30 meter imagery. Lastly, since 1987 there may be a trend of tree island/brush communities replacing wet prairie communities in the northern part of the Refuge and a transition to wet prairie communities in place of tree island/brush communities in the southern portion of the Refuge. / by Dorianne M. Barone. / Thesis (M.S.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, FL : 2008 Mode of access: World Wide Web.
463

Ecological impacts of ash dieback in Great Britain

Hill, Louise January 2017 (has links)
Ash dieback is a severe disease of ash trees (Fraxinus spp.), caused by the invasive fungus Hymenoscyphus fraxineus. In its native East Asia, H. fraxineus is a harmless endophyte, but since its accidental import into Europe in the early 1990s it has infected over 90% of ash trees in some areas, with long-term mortality sometimes exceeding 90%. The disease was discovered in Great Britain in 2012, and has since spread rapidly. This thesis investigates some of the possible impacts on biodiversity, ecosystem functioning, and society, and in doing so identifies ways to alleviate some impacts. Britain has only 13% tree cover (among the lowest in Europe), so may be particularly vulnerable to ash loss. Better understanding of the effects and how to minimise them is critical to deliver an evidence-based response. First, we investigated impacts in woodlands by experimentally killing woodland ash trees by ring-barking. We found no short-term effect of ash loss on ground flora or earthworm communities, or on the regeneration or growth of other woody species. Observational evidence suggested that remaining canopy trees rapidly filled gaps left by ash, perhaps contributing to stability. Our woodlands appeared to be remarkably resilient to ash loss, although there may be long-term effects or impacts on other species that this experiment failed to observe. To investigate broader-scale impacts, we required high-quality abundance maps for ash and other trees across Britain. Using species distribution modelling and random forest regression, we developed a protocol to produce abundance maps from readily available data. We tested the predictive power of the resulting maps using cross validation. Our maps are the best available for abundance of British tree species, and will be useful across a wide range of disciplines. We then used them to model ecosystem vulnerability to ash loss, based on the abundance of ash and other tree species, and their ecological trait similarity. We identified areas at risk of the largest impacts, and produced guidance for positive management actions to minimise ecological change. Lastly, we investigated the financial impacts of ash dieback, estimating the total cost to Britain at £9.2 billion. This figure is many times larger than the value of lost trade if biosecurity were improved to prevent future invasions, questioning the validity of financial arguments against biosecurity. We also found that loss of ecosystem services accounted for less than a third of the total cost, suggesting that ecosystem service assessments may miss a large proportion of the true cost of biodiversity loss. Overall, we found that some impacts may be less than expected, such as local effects on woodland ground flora, and others, such as the economic cost, may be much larger than expected. However, the resilience of ecosystems to a major shock such as loss of a common species, and actions to mitigate the impacts, depend on having a diversity of other trees present. The ash dieback outbreak highlights the importance of preventing other severe pests and diseases of trees from being introduced; something that has been increasing exponentially, largely due to international trade in trees. This thesis provides further firm evidence that there is an ecological and social imperative to halt this trend.
464

Applying cross-channel user experience design theory to practice : A case study of a public transportation company in Sweden

Lång, Ida, Schlegel, Anne January 2015 (has links)
The emergence of digital technology, social media and ubiquitous computing in the 21stcentury changed customer behavior and created new possibilities, but also challenges, forcompanies offering their services. The new customer generation is more tech-savvy thanever before, and therefore places higher demands on companies to have well-designed experienceswith services that can be consumed through various channels. This study investigatesthese service environments to see if they are actively shaped to cross-channel ecosystemsby the companies or if the companies react to the demands of their customers. Furthermore,the goal of this thesis is to find out how the current theory of cross-channel userexperience can assist in formulating design strategies for service ecosystems. To determinethis, the authors conducted a theoretical analysis of the current IS literature and created,based on that, a cross-channel user experience design framework. Within a case study of aSwedish transportation company, company and user interviews, direct observations of theavailable service artifacts, analysis of documentation, and the design of the user journeyswere executed to assess the as-is ecosystem. On the basis of these results, it was proventhat cross-channel ecosystems are shaped based on user demands. The created frameworkwas applied to formulate a language of critique of the cross-channel user experience designof the underlying case study, and the framework was proven to be applicative to practiceafter adjusting it to its final version.
465

Recreational ecosystem service benefits from the Chestermere Lake Reservoir : value for day use non-resident visitors

Bewer, Robert January 2012 (has links)
Irrigation infrastructure provides many ecosystem service (ES) benefits that enhance the well-being of Albertans and is central to economic activity in southern Alberta. Management of irrigation infrastructure and water resources is becoming increasingly challenging as Alberta’s population and economy grows. Past water allocation decisions have not generally considered the need of ecosystems leading to declining ecosystem health, and changes to provision of ES benefits in Alberta. The goals of current Alberta government policy include changing how water and land is managed to ensure that ecosystem health and ES provision is maintained. The research in this thesis concentrates on establishing the value of recreational ES benefits provided by the Chestermere Lake Reservoir, and obtaining information on the spatial aspects and visitor characteristics. A mixed method approach is used combining a qualitative discussion with a quantitative analysis using a geographic information system (GIS) and the travel cost method (TCM). The selection of the mixed method and combined GIS-TCM approach was based on past success in previous studies. The findings reveal a substantial value for recreational ES benefits provided by the Chestermere Lake Reservoir occurring within a limited area similar to other studies of recreational benefits from reservoirs. The findings of this research provide information for decisions makers, water infrastructure managers, and water transfer participants when assessing the impact of planned actions. Further research is recommended to build upon the findings of this study and further expand the available information on ES benefits to include all ES provided by southern Alberta. / x, 125 leaves : col. ill. ; 29 cm
466

Ecosystem modelling of the data-limited, oligotropic KwaZulu-Natal Bight, South Africa.

Ayers, Morag Jane. 08 November 2013 (has links)
Ecosystem modelling allows for an understanding of the structure and functioning of ecosystems. During this study, the oligotrophic KwaZulu-Natal (KZN) Bight, a data-limited system on the east coast of South Africa, was modelled. A framework for modelling data-poor systems, incorporating the construction of multiple models, sensitivity analyses and comparative analyses was applied to the Bight using literature data. Models converged on general trends of ecosystem functioning showing 99% of flows originated from detritus, primarily imported from rivers. The largest source of riverine detritus is the Thukela River which flows into the central Bight. This area supports a shallow-water prawn trawl fishery which targets penaeid prawns. Fisheries time series‘ were incorporated into the model framework to study the effects of prawn trawling and the decrease in prawn recruitment, caused by estuarine nursery loss, on the central Bight ecosystem. Dynamic simulations suggest the biomass of biotic groups were more affected by prawn recruitment level than trawling effort level. To understand the importance of nutrients in more detail, nutrient content, biomass and stoichiometric ratios were documented for various pelagic and demersal functional groups, and compared between areas in this oligotrophic system. Results showed the central Bight had the highest carbon, nitrogen and phosphorus biomasses, due to riverine nutrient sources, and the southern Bight had the lowest. In addition, the demersal community had higher biomasses than the pelagic community for all nutrients. Nutrient dynamics and limitations within the Bight were explored through the construction and analysis of trophic flow networks of carbon, nitrogen and phosphorus for the southern, central and northern Bight. Network analyses suggest nutrient cycling was lowest in the central Bight, and highest in the southern Bight. Cycling of nitrogen was highest in all areas due to the dominance of benthos, in terms of biomass, which was nitrogen-limited. Higher trophic levels were found to be phosphorus-limited. However many pelagic groups were co-limited by nitrogen and phosphorus, probably due to the oligotrophic nature of the bight. This suite of ecosystem models provides the first holistic view of the KZN Bight and an understanding of ecosystem functioning in the southern, central and northern Bight. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2012.
467

Marine nutrient dynamics of the KwaZulu-Natal bight : assessing bacterial numbers, biomass and productivity.

Kunnen, Travis Hank. 07 November 2013 (has links)
The KwaZulu‒Natal Bight is formed from a narrow indentation in the SE coast of South Africa with the waters within considered to be oligotrophic. These waters therefore depend on both allochthonous sources of nutrients such as intermittent upwelling of deeper water and nutrients supplied by riverine inputs, as well as the autochthonous nutrients supplied by phytoplankton production, microbial fixation and recycling of nutrients by the microbial loop. Two African Coelacanth Ecosystem Programme cruises were undertaken during 2010, during the wet summer, and dry winter months. During each cruise, the waters of the KZN‒B were sampled rapidly to provide spatial scales (synoptic) of bacterial abundance and biomass, as well as at four predetermined locations to determine temporal scales (focus) of bacterial abundance, biomass and productivity. During the synoptic section, samples were taken in surface waters, close to F‒max (the depth at which phytoplankton were at their most dense as determined by in situ fluorometry), below the F‒max (where depths exceeded 50 m), and near the bottom. These samples were fixed with formaldehyde, stained with DAPI and cells were visualised by epifluorescent microscopy. During the focus section, samples were taken in surface waters, close to F‒max and below F‒max and incubated with 3H‒Thymidine to determine bacterial productivity. Bacterioplankton dynamics (numbers, biomass and productivity) for both cruises, synoptic section, were higher within the photic zone and near riverine influenced waters, with summer showing higher dynamics than winter. Irrespective of season, bacterioplankton dynamics decreased with increasing distance from the coast as well as with increasing depth, potentially via bottom‒up control mechanisms. Results obtained from the focus section of both cruises showed a significant difference between seasons for the Thukela Mouth and Richards Bay North, while no difference at the Durban Eddy. These results from the focus section suggest that bacterioplankton temporal dynamics were more top‒down controlled, rather than environmentally influenced, resulting in fluctuating dynamics over time. Overall, it is proposed that the degree of inorganic nutrient supply to the phytoplankton, resulted in the formation of DOM for use by the heterotrophic bacteria, resulting in a bottom‒up control mechanism, where Chl‒a concentrations within the euphotic zone induces either top‒down or bottom‒up control mechanisms on the heterotrophic bacteria directly affecting their numbers, biomass and productivity. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2013.
468

Methodology for capturing environmental, social and economic implications of industrial symbiosis in heavy industrial areas

Kurup, Biji R. January 2007 (has links)
Industrial operations have been attributed to causing social and environmental problems such as: acid rain; greenhouse gas emissions, air, water and soil pollution; plus health problems to neighbourhood communities. With the 3P (people, planet, profit) approach for sustainability as the background, there have been movements to establish the concept of eco-industrial development in existing or new industrial areas from the planning stage onwards. Industrial ecology (IE) is the operation of an industrial ecosystem which is based on the principles of operation of a natural ecosystem. Industrial symbiosis (IS), one of the principal applications of IE, is defined as inter-firm collaboration, where a network of industries collaborates in exchange of products, by-products, information, resources and wastes to reduce their collective environmental footprint to achieve mutual benefits. / Industrial symbiosis is a collaborative process of industries geographically located in an industrial park, which facilitates and enables an exchange of products, by-products and wastes to reduce the collective adverse impacts of the emission during the operation of these industries. However, IS faces a number of barriers. Importantly, it has been identified that there is a critical impediment to implementing future IS practices in the area. This is because of the number of barriers such as technical, regulatory, commercial as well as informational. In addition, there is an absence of a proven and well established evaluation methodology to identify the benefits of such practice. The true implications of IS might therefore remain underestimated, thereby failing to convince industry, government and the community to realize the opportunities IS can bring in attaining goals of sustainability in their operations. / The aim of this PhD research was to develop and trial a method for capturing the life cycle environmental, social and economic implications of industrial symbiosis in heavy industrial areas. This research was based on multi-disciplinary approach of examining environmental, social and financial aspects to develop an integrated method. In the Kwinana industrial Area (KIA), the primary research area in Western Australia, the opportunities were significant for such industrial symbiosis to happen because of the co-location of diverse industries. The research hypothesis that informs this thesis is that the assessment of implications of present IS might bring further opportunities for enhancing symbiosis between industries. Though the primary emphasis of the research was in the Kwinana Industrial Area, this approach could be applied to other heavy industrial areas. This site could be significant both nationally and internationally in providing a platform for business responses to regional sustainable development challenges, by documenting best practice and improving approaches for implementing industrial symbiosis. / This research addressed the objectives by using the developed Six Capitals Model (SCM) for identifying environmental, social and economic benefits. The values under these dimensions were analysed with regard to natural, ecosystem, human, social, financial and manufactured capitals for a project of wastewater reclamation for industrial use. Under the environmental dimension, the model revealed that resource conservation and resource security were achieved as a result of the operation of this project. These results are in line with the argument that industrial symbiosis secures and conserves resources due to the possibility of reclaiming the resources that were once discarded. Water contamination has been reduced as a result of the operation of this project. This indicator shows that there is an improvement in maintaining the ecosystem capital. / In terms of human capital, sharing information between industries and opportunities of sharing infrastructure and technology has been improved. Regarding community capital, sharing of information between industries and communities, has increased as a result of this project. Collaboration of government bodies, level of understanding about IS projects due to increasing communication between various stakeholders, and increase of employment opportunities are notable, as value has been generated for community capital since the project started. In terms of financial capital of the project, the majority of the participants did not gain any financial savings in terms of direct costs but rather accrued short term costs. This was due to the infrastructure cost involved as part of installation of pipes and pumps. It was also due to the high cost of the reclaimed water than the scheme water. In addition, the analysis showed that most of the participants of the project did not gain any savings in the indirect costs such as hidden and legal costs, such as permit costs, compliance costs, future fines and penalties. However, as part of manufactured capital, there were savings due to improved business opportunities as well as infrastructure, for business and community collectively. / The results of this thesis show that broader benefits of symbiosis can be achieved, not only from operation of the project, but also from the influence of processes of symbiosis. Among them are connection, communication and collaboration between the project partners. There has been a substantial increase in the networking of industries and formation of multi groups for addressing various issues faced by industry and community in the Kwinana. There has also been a further increase in the transparency of information dissemination and communication through industries council’s website. In addition, there has been an improvement in the rate of participation of community members and groups in the Communities and Industries Forum (CIF) which resulted in the formation of further stakeholder groups by industries council as a platform for addressing the issues of industries and communities. / IS practices strengthen the EIP concept and increase the chances of sustainable industrial development regionally due to collaboration of community of businesses and local and regional community. IS also increases the reputation and license to operate in the community. There are many advantages for using the Model developed in the thesis to assess the benefits of IS. First, the values of ecosystem values maintained are able to be accounted for in addition to natural capital values. The Six Capital Model can also account human capital values in addition to community capital. The Model also accounted the manufactured capital in addition to financial capital and it gives an opportunity to identify the value generated towards community and companies. / Finally, the Model enables a calculation of the internal costs and external costs and benefits so that industries are able to understand the real cost of the projects. One of the main advantages of this method is that with, right indicators, the intangible values of the IS process can also be assessed and reported.
469

Riparian buffer function with respect to nitrogen transformation and temperature along lowland agricultural streams in Skagit County, Washington /

Monohan, Carrie Elise. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 84-94).
470

Ecological impacts of biodiversity enrichment in oil palm plantations

Teuscher, Miriam 27 November 2015 (has links)
No description available.

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