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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.
1

Resistência e resiliência de assembleias zooplânticas (Copepoda, Cladocera e Rotidera) frente a pertubações /

Portinho, Jorge Laço. January 2015 (has links)
Orientador: Marcos Gomes Nogueira / Banca: Raoul Henry / Banca: Gilmar Perbiche-Neves / Banca: Claudia Bonecker / Banca: Virginia Sanches Uieda / Resumo: Não disponível / Abstract: Not Available / Doutor
2

Restauração do cerrado: a influência das técnicas e de fatores ecológicos sobre o desenvolvimento inicial da comunidade lenhosa / Restoration of the cerrado: the influence of technical and ecological factors on the initial development of the woody community

Cava, Mário Guilherme de Biagi [UNESP] 29 August 2014 (has links) (PDF)
Made available in DSpace on 2015-03-03T11:52:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-08-29Bitstream added on 2015-03-03T12:07:38Z : No. of bitstreams: 1 000814296.pdf: 5372087 bytes, checksum: 24867b0ab53b315554784175f47f5f40 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A restauração da vegetação de cerrado é um desafio aos cientistas e restauradores, familiarizados com os obstáculos e processos peculiares da restauração florestal, mas que não se adequam ao ecossistema savânico. A técnica mais utilizada tem sido o plantio de mudas, que pode apresentar elevados custos, principalmente para restauração em larga escala. A semeadura direta de espécies lenhosas e técnicas de indução da regeneração natural têm sido recomendadas como alternativas ao plantio de mudas visando à restauração do Cerrado. Implantamos experimento em blocos ao acaso, com cinco tratamentos (técnicas de restauração) e quatro repetições, em uma pastagem abandonada, em área de cerradão, na região do Alto Xingu, Mato Grosso, Brasil. As técnicas envolveram a semeadura direta mecanizada em linhas e a lanço, plantio de mudas, regeneração natural assistida (aplicação de herbicida para controle de gramíneas invasoras) e controle (área sem intervenção). Amostramos a vegetação da área aos 22 meses após a implantação do experimento. Contabilizamos e identificamos todos os indivíduos de espécies lenhosas que ocorreram nas parcelas de amostragem, com 50 cm de altura mínima. Posteriormente, calculamos a densidade e a riqueza da comunidade, como indicadores do sucesso da restauração. Registramos 14892 indivíduos por hectare, pertencentes a 112 espécies. Dentre estas espécies, 16 foram plantadas e 96 regeneraram-se naturalmente por chuva de sementes ou rebrota. A semeadura direta em linhas foi superior às outras técnicas na recuperação da densidade. Este atributo da comunidade também foi influenciado pelo tipo de solo e, de forma secundária, pelo histórico de uso da terra. Por outro lado, a semeadura direta, em geral, resultou em comunidades com baixa diversidade, com forte dominância de uma única espécie ... / The restoration of the Cerrado vegetation is a challenge to scientists and practitioners, familiar with the obstacles and peculiar processes of forest restoration, which do not fit to the savanna ecosystem. The most widely used technique has been the planting of nursery raised seedlings, which may have high costs, especially for large-scale restoration. The direct seeding of woody plants and techniques for induction of natural regeneration have been recommended as alternatives to planting nursery raised seedlings, aiming to restore the Cerrado. We implemented an experiment in randomized blocks with five treatments (restoration techniques) and four replications, in an abandoned pasture previously occupied by cerradão (the forest-type of cerrado vegetation) in the Upper Xingu region, Mato Grosso, Brazil. The techniques involved direct mechanized seeding – broadcast and in rows, planting nursery raised seedlings, assisted natural regeneration (application of herbicide to control invasive grasses) and a control (area with no intervention). We sampled the vegetation of the area at 22 months after the restoration interventions. We recorded and identified all woody plants with a minimum height of 50 cm occurring in the sample plots. Subsequently, we calculated the density and richness of the community, as indicators of restoration success. We recorded 14892 individuals per hectare, belonging to 112 species. Among these species, 16 were planted and 96 regenerated naturally by seed rain or resprout. The direct sowing in rows was superior to other techniques in the recovery of the density. This attribute of the community was also influenced by soil type and, secondarily, by historical land use. On the other hand, direct seeding usually results in communities with low diversity and with high dominance of a single species. No restoration technique resulted in higher richness than the other ...
3

Resistência e resiliência de assembleias zooplânticas (Copepoda, Cladocera e Rotidera) frente a pertubações

Portinho, Jorge Laço [UNESP] 27 March 2015 (has links) (PDF)
Made available in DSpace on 2016-08-12T18:48:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-27. Added 1 bitstream(s) on 2016-08-12T18:50:57Z : No. of bitstreams: 1 000865286.pdf: 2639165 bytes, checksum: 47e4a77e4ffbbf821330283c376b724d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / CAPES: BEX 12951/12-9
4

Restauração do cerrado : a influência das técnicas e de fatores ecológicos sobre o desenvolvimento inicial da comunidade lenhosa /

Cava, Mário Guilherme de Biagi, 1985. January 2014 (has links)
Orientador: Gisele Durigan / Coorientador: Ingo Isernhagen / Banca: Daniel Luis Mascia Vieira / Banca: Vera Lex Engel / Resumo: A restauração da vegetação de cerrado é um desafio aos cientistas e restauradores, familiarizados com os obstáculos e processos peculiares da restauração florestal, mas que não se adequam ao ecossistema savânico. A técnica mais utilizada tem sido o plantio de mudas, que pode apresentar elevados custos, principalmente para restauração em larga escala. A semeadura direta de espécies lenhosas e técnicas de indução da regeneração natural têm sido recomendadas como alternativas ao plantio de mudas visando à restauração do Cerrado. Implantamos experimento em blocos ao acaso, com cinco tratamentos (técnicas de restauração) e quatro repetições, em uma pastagem abandonada, em área de cerradão, na região do Alto Xingu, Mato Grosso, Brasil. As técnicas envolveram a semeadura direta mecanizada em linhas e a lanço, plantio de mudas, regeneração natural assistida (aplicação de herbicida para controle de gramíneas invasoras) e controle (área sem intervenção). Amostramos a vegetação da área aos 22 meses após a implantação do experimento. Contabilizamos e identificamos todos os indivíduos de espécies lenhosas que ocorreram nas parcelas de amostragem, com 50 cm de altura mínima. Posteriormente, calculamos a densidade e a riqueza da comunidade, como indicadores do sucesso da restauração. Registramos 14892 indivíduos por hectare, pertencentes a 112 espécies. Dentre estas espécies, 16 foram plantadas e 96 regeneraram-se naturalmente por chuva de sementes ou rebrota. A semeadura direta em linhas foi superior às outras técnicas na recuperação da densidade. Este atributo da comunidade também foi influenciado pelo tipo de solo e, de forma secundária, pelo histórico de uso da terra. Por outro lado, a semeadura direta, em geral, resultou em comunidades com baixa diversidade, com forte dominância de uma única espécie ... / Abstract: The restoration of the Cerrado vegetation is a challenge to scientists and practitioners, familiar with the obstacles and peculiar processes of forest restoration, which do not fit to the savanna ecosystem. The most widely used technique has been the planting of nursery raised seedlings, which may have high costs, especially for large-scale restoration. The direct seeding of woody plants and techniques for induction of natural regeneration have been recommended as alternatives to planting nursery raised seedlings, aiming to restore the Cerrado. We implemented an experiment in randomized blocks with five treatments (restoration techniques) and four replications, in an abandoned pasture previously occupied by cerradão (the forest-type of cerrado vegetation) in the Upper Xingu region, Mato Grosso, Brazil. The techniques involved direct mechanized seeding - broadcast and in rows, planting nursery raised seedlings, assisted natural regeneration (application of herbicide to control invasive grasses) and a control (area with no intervention). We sampled the vegetation of the area at 22 months after the restoration interventions. We recorded and identified all woody plants with a minimum height of 50 cm occurring in the sample plots. Subsequently, we calculated the density and richness of the community, as indicators of restoration success. We recorded 14892 individuals per hectare, belonging to 112 species. Among these species, 16 were planted and 96 regenerated naturally by seed rain or resprout. The direct sowing in rows was superior to other techniques in the recovery of the density. This attribute of the community was also influenced by soil type and, secondarily, by historical land use. On the other hand, direct seeding usually results in communities with low diversity and with high dominance of a single species. No restoration technique resulted in higher richness than the other ... / Mestre
5

An assessment of the capacity of waterfront developments to adapt to climate change : a case study of the Point Waterfront Area, Durban.

Sogoni, Zukisa. 22 September 2014 (has links)
This research set out to investigate the resilience of the Point Waterfront Development in Durban, South Africa, with regards to climate change. Considering that South Africa is a Third World country, the assumption was that Point Waterfront area would fall short of resilience when it comes to climate change. This research made use of primary and secondary data from the Point Waterfront case study. Primary data were obtained through semi-structured interviews with key stakeholders of the Waterfront development. These are The eThekwini Municipality Planning and Economic Development units, Laurusco Developments, Durban Point Development Company and the local Ward Committee and Councilor. Secondary data were obtained through recent publications in the form of municipal reports, newspapers, internet articles, and books had the relevant data on the resilience of Waterfront developments to climate change. Findings suggest that the Point Waterfront is relatively safe unless something of very extreme nature comes along in terms of sea level rise from the Indian Ocean. All the stakeholders are aware of what climate change might do to the development but the municipality is, the findings suggest, the only stakeholder that goes an extra mile as to improve the resilience of the Point Waterfront and of the city of Durban at large. There seems to be some irregularities when it comes to funds as the municipality does not have enough to tackle adaptation on its own. As a recommendation, waterfront developments should be approved only aftermeasures that enable them to be resilient to climate change have been put in place.Developers must ensure efforts to mainstream the issue of climate change adaptation. Policies should be put in place to formalize adaptation among residents. An example would be instituting a policy requiring every property to have a green roof. / Thesis (M.T.R.P.)-University of KwaZulu-Natal, Durban, 2013.
6

Development of a resource model for greening environmental resilience: socio-eco efficiency framework analysis at Kombolcha Industrial Zone, Ethiopia

Kedebe, Tefera Eshete 07 1900 (has links)
This study used the socio-eco efficiency framework as an application tool to resilience the green environment at Kombolecha industrial zone by balancing the water consumption growth and green environmental tradeoffs. In addition, it aimed to determine the significant indicators, which associated with the water consumption and recycling efficiency. The consumers (factories and households) socio-eco efficiency practices were limited and then caused groundwater degradation and green environmental depletion. Previous studies, for instance, BASF (2009), ESCAP (2011) eco-efficiency, and Sailing et al., (2013) SEE balance (socio-eco efficiency) analysis targeted the company’s product portfolio and quality improvement. This study, however, considered both factories and household’s consumption activities that were proven to manifest in a complex water consumption compared to the production process. The study integrated social, economic and environmental indicators and determined the socio-eco efficiency effects on theresource consumption growth and green environment tradeoffs; water consumption and recycling efficiency. Subsequently, the study then developed a socio-eco efficiency model that used to balance the gaps between water consumption and recycling intensity inefficiency. The socio- eco efficiency indicators could, thus, be an applied tool that could be measured by employing the binary logistic regression, instrumental variable model, simultaneous equation model and the propensity score matching estimation. Based on this, this study results indicated that the household’s awareness, perception and consumption behaviours concerning the green mind adoption, product, market, technology and jobs use were strongly associated and influenced by the water resource consumption growth and green environment tradeoffs at the 5 percent significance level. Particularly, the household’s social aspects, consumer’s culture, behaviour and poverty; economic (monthly income) and environmental aspects (waterquantity limit and waste recycle) were found to bestatistically significant and strongly altered the water resource consumption and recycling efficiency by 0.000 values at the 95 percent confidence level. This study implication was thesocio-eco efficiency framework, which was key the finding of the study that holds the three key indicators, did directly associate and significant determine the factories and household’s groundwater consumption and recycling intensity differently by 0.000 values at the 95 percent confidence level. The socio- eco efficiency model could thus be an analytical tool that could be applied into groundwater consumption and recycling process. The socio-eco efficiency resource model, which is a key tool to resilient the green environment, optimized the water consumption and recycling efficiency and could be incorporated into the groundwater and green environment protection policy of Ethiopia. This study, in a circular fashion, proved socio-eco efficiency application and resolved some of the consumption paradox in the factories and household’s groundwater consumption and recycling processes. Thenon-integrated indicators and inapplicability of the socio-eco efficiency framework, nonetheless, made the green environment cautiously. So that a tactical integrative socio-eco efficiency resource model, particularly, green finances, such as green water tax, lease, paymenhave to be incorporated during the groundwater consumption that recovers the green environment attainments in Kombolecha and at large in Ethiopia. / Environmental Sciences / Ph. D. (Environment Management)
7

Resiliência de modos de vida na Praia do Aventureiro, Ilha Grande (RJ) : uma trajetória de mudanças socioecológicas / Livelihoods resilience at Praia do Aventureiro, Ilha Grande (RJ) : a pathway of social-ecological changes

Prado, Deborah Santos, 1988- 23 August 2018 (has links)
Orientador: Cristiana Simão Seixas / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T17:38:48Z (GMT). No. of bitstreams: 1 Prado_DeborahSantos_M.pdf: 4539004 bytes, checksum: 00ac403fb11bb6fbee316a66f55a9ed8 (MD5) Previous issue date: 2013 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Mestrado / Ecologia / Mestra em Ecologia
8

Development of resilience scale and examination of relationships among resilience, physical activity and mental health for older adults in Hong Kong

Hu, Chun 24 December 2019 (has links)
Introduction: Resilience is an important trait and mechanism for older adults facing adversity in their later life. Physical activity has been established as an important determinant of mental health among older adults, in which relationship of resilience may play a mediating role. In order to examine the relationships among resilience, physical activity, and mental health in older adults, the current project is designed to conduct three studies. Study-1 aims to use qualitative method to identify the characteristics that contribute to resilience in a group of community-dwelling older adults in Hong Kong. Study-2 aims to develop and validate an age-specific resilience scale, named as "Resilience Scale for Chinese Older Adults (RSCOA)". Study-3 aims to test a model in which physical activity is hypothesized to influence mental health in path mediated by resilience. Methods: Twenty-five Chinese older adults (2 males, 23 females) aged 69 to 100 years (M=80.00, SD=39.08) were included in Study-1. Interviews were conducted to collect information about the adverse events in their lives, as well as their attitudes towards adversity and the beliefs underlying their approaches to overcoming adversity. The transcripts were analysed using qualitative content analysis. In Study-2, a sequential approach was used to develop the RSCOA in three stages. In stage 1, scale candidate items were generated and initial content validity of the RSCOA were explored. In stage 2, the factorial structure of the RSCOA was extracted using exploratory factor analysis. In stage 3, exploratory structural equation modeling was conducted to test the structure. The reliability and validity of the RSCOA were also examined. In Study-3, cross-sectional data was collected from a sample of 293 Chinese older adults [60 males, 233 females; age from 65 to 95 years old (M=76.58, SD=7.02)] from eight community senior centres located in three districts in Hong Kong. Correlation analyses were performed and path analysis was employed to assess the associations among physical activity, resilience and mental health variables. Results: In Study-1, 7 themes were emerged from the interviews: 1). Equanimity- the realisation that life has both joys and sorrows. 2). Positive attitudes towards life. 3). Meaningfulness- the realisation that life has a purpose and is full of hope. 4). Self-reliance- a belief in one's capabilities and the realisation that each person's life path is unique. 5). Social support- which comes from family and friends, health care professionals, staff in the senior centres and others' appraisal. 6). Environmental support- which includes the support from neighbours, community senior centres and government. 7). Spirituality and faith- which can take the form of a belief in destiny, gratitude or religious faith. For the scale development and validation, a pool of 70 candidate items for RSCOA was established with good content validity in stage 1. In stage 2, seven factors, namely perseverance, self-reliance, spirituality, social support, living in the moment, environmental support, and meaningfulness, reflecting internal, external and existential dimensions, were identified and reflected in 27 items in the construct of resilience. In stage 3, the 27-item RSCOA was further examined, by which 3 items were deleted to achieve acceptable internal consistency (α= 0.87) and good concurrent as well as construct validities, and finally a 24-item RSCOA was confirmed. The measurement model displayed satisfactory model fit and proven invariant across gender. Building on the three path models, it was found that significant mediation effects of resilience on the relations from physical activity to depression (β =-.54, p=.002), from physical activity to loneliness (β=-.25, p=.005), as well as from physical activity to psychological well-being (β=.37, p=.008). In sum, the results confirmed that resilience mediates relationship from physical activity to mental health among the older adults. Conclusion: The qualitative analysis found that resilience of the Hong Kong older adults is characterised by internal, external and existential factors. A reliable and valid age-specific instrument for measurement of resilience in Chinese older people was developed. Older adults who are more physically active reported greater psychological well-being and less mental health problems, and the effects were mediated by resilience. The results may be useful for developing interventions that aim at assisting older adults to enhance the positive experiences and mental health in their lives.
9

Resilience of large river basins : applying social-ecological systems theory, conflict management, and collaboration on the Mekong and Columbia Basins

MacQuarrie, Patrick R. 11 July 2012 (has links)
River basins provide essential services for both humans and ecosystems. Understanding the connections between ecosystems and society and their function has been at the heart of resilience studies and has become an increasing important endeavor in research and practice. In this dissertation, I define basin resilience as a river basin system's capacity to absorb, manage, and adapt to biophysical, social-economic, and political changes (or stressors) while still maintaining its essential structure, feedbacks, and functional integrity. I address the question of resilience, scale, and development in the Mekong and Columbia River Basins. This dissertation answers the following questions: 1) is systems theory an appropriate model to evaluate basin resilience, 2) is the Mekong Basin resilient, 3) are the Mekong and Columbia River Basins resilient across multiple scales, 4) can conflict management and collaborative learning enhance resilience, 5) can a resilience framework be used for basin comparisons, and 6) what lessons can the Mekong basin take from rapid development in the Columbia basin? In Chapter 2, I create and apply a social-ecological systems (SES) model of the Mekong River Basin to assess resilience at sub-basin (provincial), watershed (national), and basin (regional) scales. Feedbacks, thresholds, vulnerability, and adaptive capacity are determined and used as inputs into an overall basin resilience assessment. Drawing upon field work done in the Mekong Basin, Chapter 3 uses Conflict Management and Collaborative Learning processes to address resilience weaknesses across multiple scales in the Mekong Basin. Chapter 4 uses the basin resilience framework to compare the Mekong and Columbia Basins against physical characteristics, development rate, conflict and cooperation, and institutional responses to development projects. In this dissertation I find the Mekong has medium-low basin resilience and that scale is a critical determinant in basin resilience assessments. I find that in this study, vulnerability is inversely proportional to resilience, and low resilience at one scale, for example fisheries in the Tonle Sap Lake in Cambodia, decreases resilience for the entire basin. I find that Cambodia and Lao PDR are the least resilience and Thailand the most resilient countries in the Mekong Basin ��� Thailand more resilient in some sectors than the Mekong River Commission (MRC). I find that the MRC's conflict management strategy is hampered by a restrictive mandate and weakness in capacity building at tributary and national scales but that Collaborative Learning processes are effective in enhancing resilience at the sub-basin scale. Finally, I demonstrate through the basin comparison that the Mekong has a highly resilient biophysical system and traditionally a resilient institutional system however, the proposed rate of development is unsustainable with trends indicating a significant erosion of resilience. I find the Columbia Basin lacking resilience in fishing, hydropower, and water quality ��� sectors mitigating the effects of development in the Columbia Basin, manifesting as overall negative trends in cooperation. However, the Columbia shows signs of increasing cooperation due recent inclusion of Tribal Nations in water management. Flexible and inclusive institutional responses to water resource development challenges, in the Mekong to rapid development on the mainstream and in the Columbia to negotiations over renewal of the Columbia River Treaty, are key determinants to whether or not each basin can halt the current negative trends and strengthen basin resilience to face the challenges now and those coming in the future. / Graduation date: 2013
10

Recovery, resilience and stability of piospere systems in the Kruger National Park.

Matchett, Katherine Jean. 27 May 2014 (has links)
Water provision is an important tool in the management of savanna ecosystems. Artificial water sources are a potential focus for degradation (biodiversity and loss of ecosystem resilience at a range of spatio-temporal scales), because they alter plant-animal interactions and soil function and stability, through the creation of piospheres. This study was undertaken as part of a drive by the Kruger National Park (KNP) to enable managers to integrate artificial waterhole management (e.g. waterhole closure or rotation) when setting goals for heterogeneity and biodiversity conservation in the park. The over-arching goal was to quantify the relationship between water provision and different attributes of heterogeneity, as part of a broader initiative to place water provision and piospheres within an ecosystem threshold framework. Herbivore utilisation gradients (piospheres) around artificial waterholes in the KNP, described in 1990, were resurveyed in 2006-2007, against a backdrop of waterhole closure in the KNP, to contribute to an understanding of the factors governing recovery and resilience in grazing systems. The responses of the plant community and soil parameters to a relaxation of herbivore utilisation pressure around closed waterholes (recovering piospheres) were examined, as were changes in the same parameters at sites that have remained open (active piospheres). These ecosystem properties were considered in relation to structural and functional ecosystem thresholds, and the piospheres surveyed incorporated a range of rainfall and edaphic gradients in the KNP. Herbaceous basal cover and soil infiltration capacity both increased significantly between 1990 and 2006/7, regardless of waterhole status. This was linked to higher rainfall in 2006/7, compared to 1990. The only vegetation variables to respond consistently to distance from water were the remote-sensed Normalized Difference Vegetation Index (NDVI) and herbaceous species composition. NDVI increased with distance from water, and annual grasses and forbs were most abundant close to water. Perennial, disturbance-sensitive climax species increased in abundance further from water. Soil analyses (N, P, pH, organic matter, and texture) and field measurements (infiltration, compaction) revealed no systematic piosphere patterns. Waterhole closure did not result in soil or vegetation recovery, but piosphere intermittency and the increases of basal cover and infiltration rate indicated that ecosystem resilience has not been compromised vii by long-term artificial water provision in the KNP. This study has shown that the traditional piosphere model is of limited use in sub-humid savanna ecosystems like the KNP during above-average rainfall periods. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

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