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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.
11

Can the environment and bird species have priority over economic interests? : A study of the protection of protected areas, bird species and their habitats.

Holmström, Linn January 2011 (has links)
Human enlargement and improvements are following the same scheme as the world economies, and have through the same structure damaged and overexploited the ecological systems of the Earth, leading to a progressive degradation of its biodiversity. The need for protected areas is now inescapable when it comes to restoring species while sustainable development and prevention of damaging the environment have become prominent. It is now even more important that the awareness of an actual impact of our living standards on the ecological system has been established. International and more specifically European Laws have been established to prevent and ensure species of all kinds to live in a safe and preserved environment, but the question of their effectiveness has to be asked and nuanced. In that respect the issue of bird species is one of major importance as they are victims of human development. Within the European member states the problem is coming from the inability of some of them to implement and apply European laws because all do not agree on the terms of a protection provided for bird species.
12

From cultural to supporting ecosystem services, the value of shelterbelts to prairie agriculture, Canada

Badin-Bellet, Louise 27 January 2014 (has links)
Shelterbelts were established in the Canadian Prairies as a means to protect soil from wind erosion. Knowledge gaps remain about shelterbelts' ecosystem services to the agro-landscape, hence hiding farmers' trade-offs in a changing agriculture. This research first investigated shelterbelts' effect on soil biological activity and fertility. Soil samples were collected in September 2012 from sheltered and non-sheltered fields in the Rural Municipality of Stanley, Manitoba. Results showed that shelterbelts promote higher soil biological activity, potentially correlated to the enhanced organic matter and micro-climate adjacent to shelterbelts. A survey was then conducted to explore shelterbelts' cultural services to the local community. Results indicated that while shelterbelts were perceived to significantly benefit community well-being, they were mainly recognised for agricultural functions. We conclude that shelterbelts are a significant element of both supporting and cultural ecosystem services, contributing to the prairie agro-system resilience. Further research and quantification of shelterbelts' socio-ecological services is recommended.
13

A Fashion System Without Getting Dressed? A Two-Strand Approach Towards Understanding How to Define and Transform a Global Complex Social-Ecological System

Palm, Celinda January 2017 (has links)
In this thesis, I view the global Fashion System in terms of hybridity, with the intention of developing a theoretical understanding of a sustainable fashion system. I explore a perpetuated micro-scale activity – getting dressed each day – as a driver of the fashion system. Thereby aiming to help in redefining and clarifying the dynamics of fashion as a complex social-ecological system, to inform of risks and opportunities towards sustainable fashion. This project has two strands; Firstly, a theoretical understanding of fashion as a social-ecological system emphasizing social and abstract representations. Secondly, an action-oriented research approach for understanding how the frameworks applied in a science-business collaborative project relate to sustainable fashion and how that affects their work. For this, I draw on Critical Realism as meta-theory, where the real world consists of both material and non-material stratified layers.  Dividing the fashion system in four stratified layers; physical, material interaction, socio-economic and culture, allows the bridging of theory and practice. I argue that three concepts hybridity, modernity and fashion are essential for visioning a future sustainable fashion system and that key social-ecological resilience theories are limited for weaving them together. I found that transformations towards sustainable fashion cannot be reduced to merely socio-technical solutions, as individual’s everyday perpetuated activity of getting dressed is linked to global negative environmental impacts. In the science-business collaborative project, key challenges were identified: inadequate amount of time, and absence of knowledge regarding the fashion industry and fashion theory as well as absence of critical reflections. Finally, I found that the concepts of affordances provide a useful link between human, ‘things’ and the abstract entities created through the value chains of the fashion system. Thus, I propose that affordances could be developed as a tool linking sustainability science, design studies and economic business models, enhancing knowledge in science-business collaborations.
14

Estudo da macro e mesofauna do solo em um sistema de produção de base ecológica. / Study of the (macrofauna and mesofauna) of soil in a ecological system base.

Krolow, Daniela da Rocha Vitória 27 March 2009 (has links)
Made available in DSpace on 2014-08-20T13:25:40Z (GMT). No. of bitstreams: 1 Tese_Daniela_da_Rocha_Vitoria_Krolow.pdf: 800162 bytes, checksum: d6be5a2cad41eee39381e7173e9858bd (MD5) Previous issue date: 2009-03-27 / The present work was carried through in a property of familiar agriculture of situated ecological base, in the locality Colônia Maciel, Pelotas, RS, Brazil. The objective of the work was to characterize quantitatively and qualitatively some groups of organisms to mesofauna (Acari, Collembola, Diplura and Protura) and the macrofauna (Formicidae, Larvae of Coleopter and Díptera and Isopoda) of soil in ecological system base in the culture of the grapevine, in which, received applications of Calda Bordalesa and the biofertilizer Supermagro are carried through. An area of grapevine orchard (ecological handling) and another one with native bush at two moments of collection had been studied two distinct areas. The first collect was in 03/10/2006 and second in 14/03/2007. Two methodologie of collect of soilborne of were used the Trap of Tretzel and the Funnel of Tüllgren. It was analyzed for the two areas, the two moments of collection and both the methodologies some physical parameters (temperature and humidity of the ground), chemical parameters (Carbon of the ground, H + Al, macronutrients and micronutrients) and biological parameters as: frequency and constancy of the soilborne. For both methods collected, the biggest population of organisms found in the orchard/grapevine in the first collect revealing more frequent the groups Formicidae and Diplura through the method of the Trap of Tretzel. The Acari and Formicidae groups are more frequent in the orchard/grapevine, in the two collections through the method of the funnel of Tüllgren and in the second collection the groups Acari and Collembola through the method of the Trap of Tretzel had revealed more frequent. The Acari group presented the biggest index of constancy for both the areas and collections through the method of the Funnel of Tüllgren, being that, Acari and Collembola had always revealed constant with the use of the Trap of Tretzel. The capacity of exchange of cátions presented the same values in both the collections in the orchard/grapevine not showing interference in the edafic 8 fauna. The application of bordalesa Calda intervened in the frequency of the Acaris and Collembolas groups in the soil surface. The alimentary habit of the Acari and Formicidae groups favored these organisms. / O presente trabalho foi realizado em uma propriedade de agricultura familiar de base ecológica situada no município de Pelotas, na localidade Colônia São Manuel, RS, Brasil, cujo objetivo foi caracterizar quantitativamente e qualitativamente alguns grupos de organismos pertencentes à mesofauna (Acari, Collembola, Diplura e Protura) e a macrofauna (Formicidae, Larvas de Coleóptera e de Díptera e Isopoda) do solo em um sistema de produção de base ecológica. Foram estudadas duas áreas distintas uma área de pomar de videira (manejo ecológico) e outra com mata nativa em dois momentos de coleta. A primeira coleta se deu em 03/10/2006 e a segunda em 14/03/2007. Utilizou-se duas metodologias de coleta de organismos edáficos a Armadilha de Tretzel e o Funil de Tüllgren. Analisou-se para as duas áreas, nos dois momentos de coleta e ambas as metodologias alguns parâmetros físicos (temperatura e umidade do solo), parâmetros químicos (Carbono do solo, H + Al, macronutrientes e micronutrientes). E por fim parâmetros biológicos como: freqüência e constância dos grupos faunísticos selecionados. Para ambos os métodos de coleta, a maior população de organismos encontrados no pomar/videira foi na primeira coleta mostrando-se mais freqüente os grupos Formicidae e Diplura através do método da Armadilha de Tretzel. Os grupos Acari e Formicidae são mais freqüentes no pomar/videira, nas duas coletas através do método do funil de Tüllgren e na segunda coleta mostraram-se mais freqüentes os grupos Acari e Collembola através do método da Armadilha de Tretzel. O grupo Acari apresentou o maior índice de constância para ambas as áreas e coletas através do método do Funil de Tüllgren, sendo que, Acari e Collembola mostraram-se sempre constantes com a utilização da Armadilha de Tretzel. A capacidade de troca de cátions apresentou os mesmos valores em ambas as coletas no pomar/videira não mostrando interferência na fauna 6 edáfica. A aplicação da calda bordalesa interferiu na freqüência dos grupos Acaris e Collembolas na superfície do solo. O hábito alimentar dos grupos Acari e Formicidae favoreceu esses organismos.
15

Ecological resilience and the interaction between the freshwater ecosystem services and built environment in the City of Tshwane, South Africa

Otto, Emmarie January 2015 (has links)
Nature and humans are intrinsic parts of the same system, called a social-ecological system (SES), wherein freshwater ecosystems form one of the important bases of the survival of all life. Human activities, such as land use and overconsumption, impact on freshwater systems; and freshwater systems also impact on the urban systems through which they flow. Changes in one part of the system, be it human or ecological, will impact on the other. If a freshwater ecosystem’s resilience is negatively affected and fails to retain its functional integrity, it will increase the vulnerability of the SES. Disregarding this connection can have a significant impact on the quality of an urban system. Throughout its history since 1855, the City of Tshwane SES has moved through different eras of change, which have altered the quality of the connection between the Apies River and the urban infrastructure through which it flows. These eras have been identified as: a) First era (1855–1909) Apies River as a natural system; b) Second era (1910–1970) Apies River becoming a hidden, polluted and disconnected freshwater system; and c) Third era (1971–2016), the era of attempts at beautification and to regenerate the Apies River freshwater system. The main goal of this study is to understand how changes in the connection between the built infrastructure in the City of Tshwane and the Apies River have affected the resilience of the Apies River’s system as an integral part of the Tshwane SES. The study achieved this by identifying the different changes, the drivers of change, and the effects that these changes have had on the resilience of the Apies River. This was carried out using the method of a historical narrative. It was concluded that the Apies River gained specific resilience but lost its general resilience and therefore its adaptive capacity. The main drivers behind the loss of general resilience of the Apies River system were: a) the lack of a local government structure to supply proper infrastructure and service delivery to the people of Pretoria, followed by an inflexible and largely unresponsive local government system lacking tightness of feedback and therefore not detecting the signals of crossing a threshold in time; and b) a lack of ecological awareness or the necessary understanding of how freshwater ecosystems function, in order to integrate natural freshwater ecosystems as a functional part of the urban infrastructure. / Dissertation (ML (Arch))--University of Pretoria, 2015. / National Research Foundation (NRF) supported this study as part of the program: Resiliency Strategies for Aspirational African Cities, through the research Grant no. 78649. Opinions expressed and conclusions arrived at, are those of the author and cannot necessarily be attributed to the NRF. / Architecture / ML (Arch) / Unrestricted
16

School integration of newly arrived immigrant children and youth

Al-haddia, Abdulhakim, King, Daniel January 2020 (has links)
The aim was to study how school professionals working with newly arrived immigrant children and youth experience how these students integrate into the school. The study is a qualitative research conducted in Sweden. The first part of the research focused on studying what factors affect the integration of newly arrived immigrant in schools while the second part focused on what strategy is used to ensure their integration. The findings of the study were thematically analyzed using the ecological systems theory as a framework of analysis. Through semi-structured interviews, four teachers and a counsellor expressed their perception on the integration of newly arrived immigrants’ student into schools. The result showed that the teachers are the core agent for integration within schools. It was shown that past experiences, family, social connections, educational background, school system, migration policies, culture are important factors that affect the integration process of these students.
17

Securing resilience to climate change impacts in coastal communities through an environmental justice perspective: A case study of Mangunharjo, Semarang, Indonesia / Säkra resiliens mot effekterna av klimatförändringar i kustsamhällen genom ett miljörättviseperspektiv: en fallstudie av Mangunharjo, Semarang, Indonesien

Hansson, Robin, Mokeeva, Elena January 2015 (has links)
Climate change impacts have been shown to increase the social, economic and ecological vulnerabilities of poor groups in coastal communities of Asian countries. Mangunharjo village in Semarang city, Indonesia, has been identified as vulnerable to sea level rise, coastal erosion, tidal inundation and flooding, and the well-being of residents is threatened due to loss of livelihoods. In order to secure their future, the community has to enhance its resilience to climate change impacts, however, additional factors are undermining thepotential of a resilient and prosperous village. As resilience theory carried out in practice could negatively affect already marginalized people if trade-offs are not identified, a complementing theory is needed. This study develops a novel joint framework of resilience theory and environmental justice for analyzing the potential of enhancin gthe community’s resilience. It also explores what is needed for the village in order to increase its resilience. The framework revealed to be successful in identifying root problems and highlighted deficiencies in current resilience strategies. Moreover, the incorporation of environmental justice broadened the perspective of what could weaken the resilience ofthe village. Hence, an environmental justice perspective complements resilience theory as it identifies potential trade-offs and analyzes whose resilience is enhanced. The framework is argued to be a useful tool to secure resilience of a social-ecological system of various scales, however, further research is needed onthe optimal linkages of the two theories.
18

Analyzing resource use decisions under global change by agent-based modeling

Dreßler, Gunnar 15 May 2017 (has links)
Achieving sustainable development to meet the needs of current and future generations is currently on top of the global agenda, both in scientific research as well as global politics. However, achieving sustainable development is still a grand challenge, not least because it is embedded in the context of global change that affects most resource use systems worldwide in multiple ways. Even though many approaches to sustainable management do consider the connection between human activity and environmental dynamics, the role of human behavior as a main driver of system dynamics in coupled human and natural systems is often only poorly addressed. In this thesis, we aim to contribute to an improved understanding under which conditions human resource use decisions lead to sustainable outcomes, with regard to global change. For this, we will take the perspective of human decision-making and its social, ecological and economic consequences in two different resource use contexts, namely a) pastoralism in drylands and b) disaster risk management with respect to floods. We explicitly consider individual human decision-making as driver of social-ecological system dynamics, investigate the feedbacks between system components, as well as the impact of global change on resource use. To analyze such complex system dynamics, simulation models have proven to be helpful analysis tools. Particularly agent-based modeling represents a flexible and powerful analysis tool, as it allows us to model the decisions and interactions of individual agents at the micro level, while at the same time observing the outcome of their behavior on a system level. Within three case studies, we develop agent-based simulation models that capture the dynamics and feedbacks of the social-ecological system under consideration in a spatially explicit way. The first study analyzes the performance of disaster management organizations under change. In the second study, we aim to detect the drivers for polarization in a pastoral system in Morocco. The last study investigates behavioral change of pastoralist households and its impact on social, ecological and economic outcome measures. By analyzing a range of scenarios in each study, we determine both the long-term impact of different decision regimes on the state of the social-ecological system as well as the dimensions of change that have the most profound impact on the system dynamics and the sustainability of resource use. Main results that could be obtained from the modeling experiments include the identification of key resources that have a high influence on the long-term system dynamics. We are also able to show that under the influence of global change, access to certain resources gains in importance, as resources can act as buffer mechanisms to mitigate the adverse effects of global change. Through the operationalization of behavioral theories in model rules and the explicit representation of heterogeneous agent decision making, we could determine under which conditions a more refined representation of human decision making matters, and when a change in behavioral strategies leads to different social-ecological outcomes. Furthermore, all three modeling studies demonstrate the usefulness of stylized agent-based models to gain insights into complex systems. Overall, this thesis contributes to social-ecological systems research by developing appropriate simulation models to address the problem of sustainable resource use under global change.
19

L'intégration des zones inondables dans la gestion de l'eau et le développement de l'irrigation d'une vallée fluviale sahélienne : le cas des terres de décrue de la moyenne vallée du Sénégal / Integration of floodplain into water management and irrigation development in a sahelian river valley : the case of flood-recession lands of the middle Senegal valley

Bruckmann, Laurent 12 December 2016 (has links)
Depuis la baisse de la ressource en eau dans les années 1970, la moyenne vallée du fleuve Sénégal est un espace en forte mutation socio-environnementale. Les politiques publiques ont régulé le fleuve à l'aide de deux barrages, Manantali et Diama, et fait de la vallée une zone d'enjeux pour le développement de l'agriculture irriguée pour l'approvisionnement en riz. Face à cette situation les zones humides de la plaine inondable, les terres de décrue, sont oubliées des politiques de développement. L'objectif de la thèse est de comprendre comment s'intègre ces terres de décrue dans les changements socio-environnementaux, et finalement définir leurs rôles actuels pour les populations locales dans la réorganisation de la moyenne vallée.Le travail s'appuie sur une étude du système socio-écologique de la plaine d'inondation de la moyenne vallée. La méthodologie comporte ainsi plusieurs volets. Une analyse hydrologique et une cartographie de la dynamique des zones inondées par télédétection a montré l'importance des choix de gestion du barrage dans l'allocation en eau pour la crue dans la vallée. Des enquêtes socio-économiques, réalisées dans quatre terroirs villageois à partir d'entretiens semi-directifs, ont mis en avant l'intégration des activités liées aux terres de décrue dans les stratégies des ménages et les fonctions économique, alimentaire et écologique assurées par les différentes unités agro-écologiques de la plaine inondable. Enfin des facteurs de mise en valeur halio-agro-pastorale des terres de décrue ont été identifiées, tels que la diversité des services écosystémiques, la valeur patrimoniale de ces espaces et l'intégration des ménages dans l'irrigation. / Since the decline of water resources in the 1970s, the middle Senegal river valley is a space dealing with many socio-environmental changes. Public policies have controlled the river with two dams, Manantali and Diama, and made the valley the preferred location for the development of irrigated agriculture for the national supply of rice. Faced to this situation, the floodplains wetlands, characterized by a flood/recession rythm, are forgotten by development policies. The objective of the thesis is to understand how these flood recession lands fit into socio-environmental changes, and finally to define their current roles for local populations into the reorganization of the middle Senegal river valley.The work is based on a study of the socio-ecological system of the floodplain of the middle valley. The methodology thus has several components. A hydrological analysis and a mapping of the dynamics of the flooded areas by remote sensing, showed the importance of the management choices of the Manantali dam in the allocation of water for the flood in the valley. Socio-economic surveys, carried out in four village terroirs and using semi-structured interviews, highlighted the integration of flood-recession related activities into household strategies, and define the economic, food supply and ecological functions between the different agro-ecological units of the floodplain. Finally, factors holding flood-recession related activities have been identified at household level, such as the diversity of ecosystem services, the heritage value of these areas and the integration of households in irrigation.
20

ENVIRONMENTAL DEGRADATION OF THE PALM SWAMPS OF THE PERUVIAN AMAZON: A MIXED-METHODS INVESTIGATION

Marcus, Matthew, 0000-0002-2445-6649 12 1900 (has links)
This dissertation investigates environmental degradation of a wetland ecosystem in the northeast Peruvian Amazon: the palm swamps, or aguajales, mostly located in the region of Loreto, Peru. This ecosystem is dominated by the dioecious palm species Mauritia flexuosa, locally known as aguaje. Female aguaje palms produce a valuable fruit which is widely consumed in the region, and especially in the capital city Iquitos. The most common method of harvesting this fruit is to chop the female palms. Concern is growing over environmental degradation that results from this practice, such as high carbon emissions released from the peat soils upon which most aguajales grow. This dissertation investigates environmental degradation of the palm swamps from multiple scales. Using a mixed-methods analysis, this dissertation asks: 1) What is the magnitude and distribution of palm swamp degradation, and what is the contribution of this process to carbon emissions? 2) What is the relative influence of physical and social underlying drivers explaining the spatial distribution of palm swamp ecosystems with different palm swamp densities? 3) How do underlying social-ecological/political-ecological driving forces occurring at different scales influence the sustainable use and conservation of palm swamp ecosystems? Degradation is mapped at the regional scale using remote sensing techniques over two periods of time: 1990-2007 and 2007-2018. Underlying drivers of degradation are investigated at the regional and district levels using spatially explicit statistical models. Finally, qualitative data acquired in the field is used to investigate why some communities successfully manage their palm swamps while others do not. This dissertation produces the first regional map of palm swamp degradation and first temporal analysis of how degradation has changed over three decades. It is the first study to analyze both physical and socioeconomic drivers of degradation and the first study to analyze how physical drivers change over time. It contributes to the literature of land change science by demonstrating a method of testing socioeconomic data at an aggregated scale against degradation data derived from remote sensing. Finally, this study provides a detailed and nuanced analysis of the aguaje social-ecological system, demonstrating that the choice of some communities to chop palms for harvest is not one made of ignorance, but rather is a logical option in marginalized communities where the aguaje fruit cannot provide a sufficient contribution to a community’s material needs. This work contributes to the literature of critical conservation by demonstrating cases of conservation success that were achieved without coercive state power. / Accompanied by 1 PDF file: chap1.pdf

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