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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.
71

Socio-ecological drivers of fish biomass on coral reefs : the importance of accessibility, protection and key species / Les déterminants socio-écologiques de la biomasse en poissons sur les récifs coralliens : importance de l'accessibilité, de la protection et des espèces clés

Maire, Eva 28 September 2018 (has links)
Les récifs coralliens hébergent la plus grande biodiversité sur Terre et fournissent la nourriture, le revenu économique, la protection côtière et les valeurs culturelles pour des millions de personnes. L'accessibilité des écosystèmes via les réseaux routiers est un déterminant majeur de leurs conditions, les écosystèmes les plus accessibles étant les plus menacées. Longtemps, l’estimation de l'accessibilité par l’Homme s’est limitée à l'utilisation de la distance linéaire qui ignore l’irrégularité des côtes maritimes et les réseaux routiers, facteurs influençant le temps nécessaire pour atteindre les lieux de pêche. Cette thèse présente un double enjeu : (i) développer des indices d'accessibilité intégrant l’hétérogénéité du milieu marin pour quantifier les impacts humains sur les récifs ; (ii) évaluer l'importance de ces nouveaux indices, en interaction avec les mesures de protection, pour expliquer les variations de la biomasse de poissons. Dans un premier temps, j’ai caractérisé la proximité des hommes aux récifs, en tenant compte des surfaces rencontrées (routes, chemin, eau) qui influencent le temps de trajet jusqu’aux récifs. Le temps de trajet a permis de calculer un indice de gravité, défini comme la population humaine divisée par le temps de trajet au carré, pour évaluer le niveau de pression humaine de n'importe quel récif au monde. J'ai trouvé que le temps de trajet et la gravité sont des déterminants majeurs de la biomasse de poissons à l’échelle globale. Dans un second temps, trois applications utilisant ces nouveaux indices ont permis de montrer que (i) la gravité permet de révéler l’efficacité des actions de conservation : les réserves placées là où les impacts humains sont modérés à forts fournissent des gains de conservation élevés pour la biomasse de poissons, mais elles sont peu susceptibles de protéger les prédateurs supérieurs, qui sont uniquement présent dans les réserves soumises à de faibles impacts humains ; (ii) en utilisant un cas d'étude réalisé dans le Nord-Ouest de Madagascar, j'ai illustré comment la proximité du marché peut affecter les communautés de pêcheurs et, finalement, engendrer des changements dans l'exploitation des ressources marines ; (iii) j’ai développé une nouvelle approche, le Community-Wide Scan (CWS), pour identifier les espèces de poissons qui contribuent de manière significative à la biomasse et à la couverture corallienne des récifs de l’Indopacifique, celles-ci pouvant constituer des espèces cibles à protéger. Dans le contexte de changements globaux et de perte de biodiversité, la mesure d’accessibilité constitue un outil puissant et permet de relancer le défi de gestion durable et efficace des socio-écosystèmes coralliens. / Coral reefs have the greatest biodiversity of any ecosystem on the planet and support ecosystem goods and services to million people who depend directly on them for food, economic income, coastal protection and cultural values. Ecosystem accessibility, through road networks, is the main driver of their conditions, with the most accessible ecosystems being most at risk of resource depletion. To date, measuring accessibility to humans was strictly limited to examining the linear distance which ignores ragged coastlines and road networks that can affect the time required to reach fishing grounds. This thesis presents a double challenge: (i) developing new metrics of accessibility that account for seascape heterogeneity to better assess human impacts on coral reefs; (ii) evaluating the importance of coral reef accessibility, in interactions with their management, to explain variations of fish biomass. First, I developed novel metrics of reef proximity to human populations and markets based on the friction distance which is related to transport surfaces (paved road, dirt road, water) influencing the effective reach of human settlements. Travel time was used to build the gravity index, defined as human population divided by the squared travel time, to assess the level of human pressure on any reef of the world. I found that both travel time and gravity are strong predictors of fish biomass globally. Second, three applications using these new metrics highlighted that (i) gravity identified critical ecological trade-offs in conservation since reserves placed with moderate-to-high impacts may provide substantial conservation gains for fish biomass while reserve locations with low human impacts were more likely to support higher-order predation, (ii) using a study case in Northwest Madagascar, I illustrated how market proximity can affect fishermen communities and, ultimately, trigger changes in marine resources exploitation, and (iii) I implemented a new Community-Wide Scan (CWS) approach to identify fish species that significantly contribute to the biomass and coral cover on Indo-Pacific reefs and which provided tractable conservation targets. Within the context of global changes and biodiversity loss, the thesis challenges the sustainable and efficient management of coral reef socio-ecological systems with accessibility being the cornerstone.
72

Social-Ecological Preferences and Urbanization in India

Bettin, Johannes 30 April 2019 (has links)
No description available.
73

Humans and Seagrasses in East Africa : A social-ecological systems approach

de la Torre-Castro, Maricela January 2006 (has links)
The present study is one of the first attempts to analyze the societal importance of seagrasses (marine flowering plants) from a Natural Resource Management perspective, using a social-ecological systems (SES) approach. The interdisciplinary study takes place in East Africa (Western Indian Ocean, WIO) and includes in-depth studies in Chwaka Bay, Zanzibar, Tanzania. Natural and social sciences methods were used. The results are presented in six articles, showing that seagrass ecosystems are rich in seagrass species (13) and form an important part of the SES within the tropical seascape of the WIO. Seagrasses provide livelihoods opportunities and basic animal protein, in from of seagrass associated fish e.g. Siganidae and Scaridae. Research, management and education initiatives are, however, nearly non-existent. In Chwaka Bay, the goods and ecosystem services associated with the meadows and also appreciated by locals were fishing and collection grounds as well as substrate for seaweed cultivation. Seagrasses are used as medicines and fertilizers and associated with different beliefs and values. Dema (basket trap) fishery showed clear links to seagrass beds and provided the highest gross income per capita of all economic activities. All showing that the meadows provide social-ecological resilience. Drag-net fishery seems to damage the meadows. Two ecological studies show that artisanal seaweed farming of red algae, mainly done by women and pictured as sustainable in the WIO, has a thinning effect on seagrass beds, reduces associated macrofauna, affects sediments, changes fish catch composition and reduces diversity. Furthermore, it has a negative effect on i.a. women’s health. The two last papers are institutional analyses of the human-seagrass relationship. A broad approach was used to analyze regulative, normative and cultural-cognitive institutions. Cooperation and conflict take place between different institutions, interacting with their slow or fast moving characteristics, and are thus fundamental in directing the system into sustainable/unsustainable paths. Ecological knowledge was heterogeneous and situated. Due to the abundance of resources and high internal control, the SES seems to be entangled in a rigidity trap with the risk of falling into a poverty trap. Regulations were found insufficient to understand SES dynamics. “Well” designed organizational structures for management were found insufficient for “good” institutional performance. The dynamics between individuals embedded in different social and cultural structures showed to be crucial. Bwana Dikos, monitoring officials, placed in villages or landing sites in Zanzibar experienced four dilemmas – kinship, loyalty, poverty and control – which decrease efficiency and affect resilience. Mismatches between institutions themselves, and between institutions and cognitive capacities were identified. Some important practical implications are the need to include seagrass meadows in management and educational plans, addressing a seascape perspective, livelihood diversification, subsistence value, impacts, social-ecological resilience, and a broad institutional approach.
74

And the ocean came up on land : perceptions of adaptive capacity of cattle ranching in Vermilion Parish, Louisiana

Adams, Danica Claire 24 February 2015 (has links)
Cattle ranching in Vermilion Parish is a social-techno-ecological system (STES) that is currently vulnerable due to changing social, technological and ecological conditions. In addressing ways to increase the adaptive capacity of cattle ranching in Vermilion Parish, I used a multiple, mixed method approach grounded in a critical constructivist framework. Constructivism is the idea that our relationship to facts is constructed by our social context. It is these perceptions that shape people’s actions. By looking at these perceptions through an emancipatory frame I was able to understand multiple interpretations of meaning, consciously address them, consider how they may have shaped our actions, and then alter those meanings and power relationships. In an effort to increase the adaptive capacity of cattle ranching in Vermilion Parish, my research focused on actions, why people perform those actions, and how to change them. This research connected the physical landscape of the marshes, the individual landscape of perception, and the conceptual landscape of resilience. If resilience is the ability of a system (cattle ranching in vermilion parish) to recover after a disturbance, adaptive capacity is when the actors within the system can influence that system’s resilience. I explored the history of cattle ranching in Vermilion Parish from three different, but overlapping perspectives – environmental, social, and technological. These perspectives compliment the information from interviews and 3CM sessions. These 15 interviews revealed the perception of 11 types of threats facing cattle ranching in Vermilion Parish. The body of literature surrounding resilience theory identifies traits of highly adaptive systems. The recommendations and suggestions outlined in Chapter 6 exist at the intersection of the actors’ perception of specific threats and the decidedly generalized traits of highly adaptive systems. These suggestions were geared towards increasing the adaptive capacity of cattle ranching in Vermilion Parish. Given these layered landscapes and their complexity, my recommendations were subject to feedback loops and long periods of integration. These recommendations contribute to the theoretical foundation detailed in Chapter 3 by identifying specific ways that the actors of this particular system may be able increase their own adaptive capacity. / text
75

Learning to bridge conservation and development: A case study of the Environmental Monitors Programme in Kruger to Canyons Biosphere Reserve

Florêncio, Cláudia January 2016 (has links)
We live in a world that faces several social and environmental problems and achieving sustainable development in contexts where it is necessary to alleviate poverty without eroding the capacity of the ecosystems to support future generations is challenging. Therefore, fostering sustainable development requires enabling both society and environment to cope with disturbances, adapt to and shape change (resilience). Literature suggests that adaptive co-management practices are appropriate for building resilience and fostering sustainable development. Additionally, studies have highlighted the role of bridging organizations in coordinating and facilitating adaptive co-management. However, adaptive co-management has not been studied in poverty contexts. This thesis aims to understand what the main tasks of bridging organizations are, and how they facilitate and stimulate adaptive co-management in poverty contexts and their role in nurturing sustainability. The Environmental Monitors Programme of the Kruger to Canyons Biosphere Reserve was chosen as a case-study. Biosphere reserves are considered learning sites for sustainable development. The programme was studied through the lenses of a bridging organization. Semi-structured interviews and participatory observation with stakeholders identified: 1) the importance of existing networks and collaborations; 2) monitoring contribution to the identification of social and environmental issues, experimentation contribution to the implementation of sustainable harvesting practices; 3) environmental education combined with social learning lead to community empowerment and adaptive responses that e.g. address erosion; 4) environmental monitors have a crucial role in linking organizations and communities; 5) challenges related to low income settings include communities’ basic needs. This study illustrates the need to address both social and ecological problems in a concerted manner, by capacitating and empowering communities while conserving the environment. Additionally, points out the need of studying alternative co-management strategies that give focus on different priorities regarding stakeholders’ interests and the influence of power in decision-making in poverty contexts.
76

Empowering the Steel Industry as a Stakeholder : Environmental Management and Communication through a Social-Ecological Approach

Berg, Alicia January 2013 (has links)
This paper explores a case study of a Swedish tool steel company undergoing a transition from traditional environmental management practices to an enterprise identifying its place as part of a social-ecological system. The Corporate Ecosystem Services Review (ESR) was utilized by the company to begin this process by focusing on ecosystem services to determine how an ESR approach contributes to environmental management in practice. What resulted moved beyond the ESR to a tailored methodology, the internalization of a systems perspective, and a proposed new environmental management system. The results of the study provide a concrete, effective method for internalizing a systems perspective through a focus on ecosystems and presents a case for further analysis into what made it successful. It also provides an example of translating theory into practice, illustrating how a company can engage in sustainable development by valuing and managing the resilience of social-ecological systems through identifying their place in that system. The value of the results can be high for the case study company as well as for business in general.
77

Embracing complexity: Dynamics governing urban drinking water supply security in Mexico City

Cortés Calderón, Sofía Valeria January 2020 (has links)
Drinking water supply insecurity is globally on the rise, and prevalent in most low and middle-income urban areas. Multiple responses have emerged to cope with the lack of a reliable and equitable supply of safe and sufficient drinking water in cities, which presents a wide range of social-ecological implications. Yet, many of the analyses to date are focused on predominantly technological, ecological, and economic perspectives, overlooking broader cultural and political dimensions. What are the elements and the interrelationship between them that sustain the lack of drinking water supply security at an urban scale? The empirical case study is located in Mexico City, the capital city of one of the most drinking water-insecure countries globally and among the world’s five largest metropolitan areas. Qualitative data is elicited from a literature review and semi-structured interviews with key experts and urban stakeholders. The results provide an integrated understanding of the proposed system structure that created and maintain the water supply problem in the long-term. Hindrances include knowledge lock-ins and critical dynamics that inhibit the political support to transition towards a drinking water security scenario. This study shows that drinking water supply crisis in the study area and other cities with similar conditions need to be understood as multi-dimensional and from a system perspective, by challenging underlying assumptions and embracing interconnectedness. Key feedback mechanisms are presented in causal loop diagrams, allowing the exploration of higher-order leverage points to reduce existing path-dependencies as one increasingly important research area, and potentially relevant for decision-makers.
78

Shifting the Sustainability Paradigm: Co-creating Thriving Living Systems Through Regenerative Development

January 2019 (has links)
abstract: Sustainability research and action in communities should be holistic, integrating sociocultural, biogeophysical, and spiritual components and their temporal and spatial dynamics toward the aim of co-creating thriving living systems. Yet scientists and practitioners still struggle with such integration. Regenerative development (RD) offers a way forward. RD focuses on shifting the consciousness and thinking underlying (un)sustainability as well as their manifestation in the physical world, creating increasingly higher levels of health and vitality for all life across scales. However, tools are nascent and relatively insular. Until recently, no empirical scientific research studies had been published on RD processes and outcomes. My dissertation fills this gap in three complementary studies. The first is an integrative review that contextualizes regenerative development within the fields of sustainability, sustainable design and development, and ecology by identifying its conceptual elements and introducing a regenerative landscape development paradigm. The second study integrates complex adaptive systems science, ecology, sustainability, and regenerative development to construct and pilot the first iteration of a holistic sustainable development evaluation tool—the Regenerative Development Evaluation Tool—in two river restoration projects. The third study builds upon the first two, integrating scientific knowledge with existing RD and sustainable community design and development practices and theory to construct and pilot a Regenerative Community Development (RCD) Framework. Results indicate that the RCD Framework and Tools, when used within a regenerative landscape development paradigm, can facilitate: (1) shifts in thinking and development and design outcomes to holistic and regenerative ones; (2) identification of areas where development and design projects can become more regenerative and ways to do so; and (3) identification of factors that potentially facilitate and impede RCD processes. Overall, this research provides a direction and tools for holistic sustainable development as well as foundational studies for further research. / Dissertation/Thesis / Doctoral Dissertation Sustainability 2019
79

A Politico-Ecological Approach of Transitional Spaces In Social Ecological Systems

Lascoutx Ruiz, Alfredo 12 April 2021 (has links)
As spatial properties that systems theoretically have, Socio-Ecological Systems are characterized by dynamism and mobility, therefore, are subject to changes in the space they occupy in the biosphere. In land ecosystems, these changes are understood as processes of evolution over time, or the result of extreme natural events, or transformation of the natural space induced by human activities. These spatial changes produce effects on the land surface and groundwater of ecosystems colonized or penetrated by elements, individuals or populations belonging to other ecosystems. These are the so-called Transitional Spaces between ecosystems. Throughout the continuous geographical space, these spatial transitions affect human and not human ecosystems in different ways. Given their ambiguous characteristics and their indefinite temporal location between urban, rural or natural spaces, transition spaces deserve to be investigated in order to know their properties and functions within the cartography that represents complex socio-ecological systems. The research is conducted from a particular perspective of Political Ecology. For this I proceed to develop an epistemological exercise on the political ecology syntagma in order to approach its concept and object of study as a hybrid discipline between social sciences and natural sciences. Interdisciplinarity as a practice, a dialectic vision regarding anthropocentrism, environmental perception as a method for an ontology of human ecology, The ecosystem as a unit of spatial analysis. These would be some of the characteristics of my ecological-political perspective. But what does transitional space mean for political ecology and what does it add to its theory? The question led me to seek the integral concept of ecosystem and to support myself in the General Systems Theory to analyze the notions of boundary and external environment as part of the classic concept of system. At that point, the notion of transitional spaces emerges implicit when recognizing the dynamic spatiality of other existing systems. v Since the research is not linear but interdisciplinary and convergent, a brief anthology of geographic and socio-spatial political thought is presented in order to connect the issue of transitional spaces with the point of view of the social sciences. Various socio-geographical, deterministic, anthropocentric, Darwinian, Marxist, modernist theories give an overview of the issues related to space and nature. With the emergence of the spatial turn, new concerns for political sociology, geography and environmental sciences are explained by the phenomenon of urban growth at the global level. In the same way, I introduce the topic of ecological spaces, specifically the concept of Ecotone, the space of transition between diverse natural ecosystems. The use of the notion of ecotone is based precisely on the perspective of the concept of political ecology developed previously. This, in turn, will allow me to introduce the FLACAM methodology into the research, which among its components has the virtue of identifying and analyzing the spatial phenomenon of physical and social Interfaces, that is, spaces of transition within human ecosystems. Several graphics and charts show the potential properties and functions of different kind of existing interfaces and ecotones. My proposal converges in using these concepts as planning tools for transitional spaces identified as Rurban Regions and metropolitan areas. A final reflection on the need for spatial research on global urban expansion and the theoretical and pragmatic advantages of the concept of intermediate cities closes the main body of the investigation.
80

Implementeringsarbetet av Grön infrastruktur i Sverige : En policyanalys om integrering av urbana ekosystemtjänster samt värdet av adaptiv planering i Stockholms län

Svantesson, Hanne, Wikström, Stina January 2020 (has links)
Urbanisation is a global trend and in the year 2050 a big part of the world's population is expected to be living in urban areas. With this demographic change comes challenges. Biodiversity is the foundation for ecosystems to create services that human welfare depends on. The so called ecosystem services create functions that have provisioning, regulating, cultural and supporting values för humans. The expansion of ecosystems is threatened around the world because of the increased urbanisation and more paved areas and less green spaces that are available for species to settle in. Green infrastructure is a management system that has become popular mainly in urban areas as a tool to conserve biodiversity and manage ecosystems in a sustainable way. By re-creating habitats and ecosystem functions a higher resilience is created in cities and through that it becomes easier to face challenges that come with a changed climate. In Sweden green infrastructure is an important component to reach global and national environmental goals. The capital of Sweden, Stockholm is growing rapidly. Because of the growing population the design of the city and the amount of green spaces is even more important to improve the ecological, economical and social aspects in society. In this study a qualitative content analysis has been made to examine how Sweden works with the implementation of green infrastructure on a national, regional and local level. By analysing three relevant policy documents an analytical framework has been used to look closer at how ecosystem services are expressed in the different levels. The result shows that ecosystem services are given a large place in the guidelines and the action plan for green infrastructure in Sweden. It is even more clear on a local level because a big part of the planprogram over the formation of the new district Årstafältet concentrates on creating ecological solutions to help ecosystem services to create its functions. The result also shows that the implementation of green infrastructure should be overarched by cooperation and transparency where more participants are included for the best possible decisions to be made. / Urbanisering är en global trend och år 2050 förväntas en stor andel av världens befolkning vara bosatta i urbana områden. Med denna demografiska förändring kommer utmaningar. Den biologiska mångfalden är en grundsten för att ekosystem ska kunna skapa de tjänster som människans välmående är beroende av. Ekosystemtjänster skapar funktioner som har försörjande, reglerande, kulturella och stödjande värden för människor. Ekosystemens utbredning hotas världen över på grund av ökad urbanisering då många ytor hårdläggs och färre gröna ytor blir tillgängliga för arter att bosätta sig i. Grön infrastruktur är ett förvaltningssystem som har blivit populärt framförallt i urbana områden för att bevara den biologiska mångfalden och förvalta ekosystem på ett hållbart sätt. Genom att återskapa livsmiljöer och ekosystemfunktioner skapas en högre resiliens i städerna och det blir på så sätt lättare att stå emot de utmaningar som kommer i och med ett förändrat klimat. I Sverige är grön infrastruktur en viktig komponent för att nå upp till globala och nationella miljömål. Sveriges huvudstad Stockholm växer i snabb takt. I och med den växande befolkningen blir utformningen av staden och andelen gröna ytor än viktigare för att förbättra de ekologiska, ekonomiska och sociala aspekterna i samhället. Denna studie har utgått ifrån en kvalitativ innehållsanalys för att undersöka hur Sverige arbetar med implementering av grön infrastruktur på nationell, regional och lokal nivå. Genom att analysera tre relevanta policydokument har ett analytiskt ramverk använts för att undersöka hur ekosystemtjänster kommer till uttryck på de olika nivåerna. Resultatet visar att ekosystemtjänster får en stor plats i riktlinjerna och handlingsplanerna för grön infrastruktur i Sverige. Än tydligare blir det på lokal nivå då en stor del av planprogrammet för utformningen av den nya stadsdelen Årstafältet inriktar sig på att skapa ekologiska lösningar för att underlätta för ekosystemtjänsterna att utveckla sina funktioner. Resultatet visar även att implementeringen av grön infrastruktur måste genomsyras av samarbete och transparens där flera aktörer involveras för att bästa möjliga beslut skall fattas.

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