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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.
61

Ecosystem Services in Spatial Planning : Towards Sustainable Development in the Swedish Physical Planning Process

Sundler, Sofie Inger January 2013 (has links)
This thesis aims at defining the connection between the increasingly popular ecosystem services theory and its practical implications for sustainable development in Swedish physical spatial planning. A literature study was made to summarize the ecosystem services and resilience thinking concepts (with an emphasis on ecosystem services), their definitions and potential uses in physical spatial planning. This overview was then applied in choosing a concept framework to be tested in a case-study: the possible changes in ecosystem services and their values in a land-use trade off situation. To gather insight into the benefits of the ecosystem services concept, compared to environmental integration into physical spatial planning on a municipal level today, the literature study was extended to encompass a short overview of environmental management in the Swedish planning system. Finally, the case study was introduced to municipal employees with strong ties to the planning process, in order to gage their opinions on the ecosystem services concept and its usefulness in planning for sustainability and increased human wellbeing. The results of these interviews showed a generally positive attitude towards the concept as a way to gather and communicate ecological and socio-cultural information to decision makers. The economic valuation was deemed less important as the method is fraught with such difficulties. Overall, the ecosystem services and resilience thinking concepts have great potential to gather the discontinuous environmental management methods toward sustainable (ecologic) development, but in order for this to happen, the municipalities need to be given the right resources, and incentives, for implementation.
62

Three Essays On Protecting Biodiversity In Developing Countries

Miteva, Daniela January 2013 (has links)
<p>Developing countries often hoard the largest number of species, but also experience very high poverty levels. This dissertation reviews the evidence of the performance common conservation interventions. I find that despite the billions of dollars channeled towards conservation efforts annually, there is still very limited evidence whether or not conservation policies work. The evidence has been limited to exceptional countries like Costa Rica and Thailand and outlines like deforestation, without considering ecosystem function and ecosystem services. Furthermore, I find that the conservation impact evaluation literature has currently not highlighted the channels through which conservation policies effect change and how the effectiveness varies with the baseline characteristics of the area. </p><p>This dissertation aims to address some of the gaps in current conservation literature. Focusing on Indonesia between 2000 and 2006, I evaluate the performance of protected areas in terms of stalling deforestation as well as providing a wide range of ecosystem services and benefits (Chapter 2). In Chapter 3 I examine the role of context in which protected areas operate and show significant heterogeneity in their performance. In Chapter 4 I develop a static spatially explicit model of household fuelwood extraction that allows me to predict the location and magnitude of spillovers when a protected area is introduced. I find that depending on the characteristics of the areas, it may be optimal for households to buy fuelwood than collect it.</p> / Dissertation
63

COUNTING ON THE ENVIRONMENT: MEASURING AND MARKETING ECOSYSTEM SERVICES IN OREGON

Nost, Eric 01 January 2013 (has links)
New markets for the conservation of so-called ecosystem services, like the ability of a wetland to mitigate floods, are emerging worldwide. According to environmental economists, these markets require some metric - ecological or otherwise - that names the relevant characteristics of the service to be traded as a commodity. But while this is often assumed to be a simple task of science, I argue that the environmental regulators, eco-entrepreneurs, and conservationists who actually design and implement metrics are not so easily brought into agreement. In “rolling-out” revamped metrics and protocols, regulators and their conservationist allies in one market in Oregon haven’t established the conditions for market success so much as they have constrained entrepreneurs. The solutions to ecosystem destruction 20 years ago - privatization, commodification, and commercialization - have become the obstacles which limit the market’s future viability. The moments when capitalists find themselves saying “let’s sell nature to save it” - or when states say it for them - can spell trouble for capitalists at the same time that they seem like their escape hatch. Still, the short-term and long-term effects of market design may differ; barriers to the market now may prove to be its success later.
64

Regime Shifts in the Anthropocene

Rocha, Juan Carlos January 2015 (has links)
Abrupt and persistent reconfiguration of ecosystem’s structure and function has been observed on a wide variety of ecosystems worldwide. While scientist believe that such phenomena could become more common and severe in the near future, little is known about the patterns of regime shifts’ causes and consequences for human well-being. This thesis aims to assess global patterns of regime shifts in social-ecological systems. A framework for comparing regime shifts has been developed as well as a public forum for discussing knowledge about regime shifts, namely the regime shift database. The most common drivers and expected impacts on ecosystem services have been identified by studying the qualitative topology of causal networks as well as the statistical properties that explain their emergent patters. Given that long time series data for ecosystems monitoring is rather sparse, and experimenting with ecosystems at the scales required to understand their feedback dynamics is rarely an option; we also proposed an indirect computationally based method for monitoring changes in ecosystem services. I hope the results here presented offer useful guidance for managers and policy makers on how to prioritize drivers or impacts of regime shifts: one take home message is that well-understood variables are not necessary the ones where most managerial efforts need to be taken. I also hope the scientific community rigorously criticize our results, but also acknowledge that when doing theoretical or empirical work, our methods tend to ignore the multi-causal nature of regime shifts. By bringing back multi-causality to the scientific debate, I hope our results offer new avenues for hypothesis exploration and theory development on the human endeavour of understanding Nature. / Transiciones críticas o cambios de régimen en ecosistemas se definen como reconfiguraciones abruptas de su estructura y función. Estos cambios, en ocasiones inesperados, se han documentado en una gran variedad de ecosistemas en todo el planeta. Algunos científicos proponen que en el futuro cercano dichos fenómenos pueden volverse más frecuentes y severos. Sin embargo, sabemos muy poco sobre las causas y consecuencias potenciales para el bienestar humano. El objetivo de esta tesis es evaluar patrones globales de cambios de régimen en sistemas socio-ecológicos. Un marco conceptual para comparar cambios de régimen y un foro público de discusión sobre el estado del arte en su conocimiento fue desarrollado en la base de datos virtual www.regimeshifts.org. Las causas más comunes y los impactos en servicios ecosistémicos más esperados han sido identificados estudiando las propiedades topológicas de redes causales, así como las propiedades estadísticas que explican sus propiedades emergentes. Dado que experimentar con ecosistemas a la escala adecuada para capturar sus mecanismos causales generalmente no es una opción, y dado que la disponibilidad de datos de largo plazo necesarios para monitorear cambios de régimen son la excepción y no la regla, proponemos un método indirecto computacional para monitorear cambios en servicios ecosistémicos. Espero que los resultados sean de utilidad para actores encargados del diseño de políticas o del manejo de ecosistemas, especialmente espero que ofrezcan una guía sobre cómo priorizar causas y consecuencias de estos cambios de régimen: una lección clave es que las variables que mejor entendemos o las que más monitoreamos no son necesariamente aquellas en las que debemos enfocar las estrategias de manejo. También espero que la comunidad científica critique con rigor nuestros resultados, pero a su vez reconozca que tanto el trabajo empírico y teórico como los métodos que comúnmente se utilizan para estudiar cambios de régimen tienden a ignorar su naturaleza multi-causal. Al enfatizar la diversidad de sus causas, espero que los resultados ofrezcan nuevas posibilidades para la exploración de hipótesis y el desarrollo de teorías para entender mejor la Naturaleza. / Abrupt och ihållande omkonfigurering av ekosystems struktur och funktion har observerats i en mängd olika ekosystem världen över. Forskning visar på att dessa fenomen antas bli vanligare och allvarligare inom vår närmsta framtid. Kunskapen kring dessa s.k. regimskiften är dock bristfällig, framförallt kring dess konsekvenser för mänskligt välbefinnande. Denna avhandling syftar till att bedöma globala mönster av regimskiften. Ett ramverk för att jämföra regimskiften, samt ett offentligt forum, “the regime shifts database”, för att främja diskussion och sprida kunskap om regimskiften, har utvecklats. De mest förekommande drivkrafter och effekter på ekosystemtjänster har identifierats genom att studera kvalitativa topologiska och kausala nätverk, samt de statistiska egenskaperna som förklarar deras framväxande mönster. Då långvariga tidsserier av ekosystemövervakning är få, och då de experiment som krävs för att förstå regimskiftens återkopplingsdynamik sällan är möjliga, föreslås också en indirekt beräkningsmetod för övervakning av förändringar i ekosystemtjänster. Resultaten från denna avhandling ämnar ger värdefull vägledning för beslutsfattare om prioriteringsordningen mellan olika typer av drivkrafter och effekter av regimskiften. En viktig slutsats är att gedigen kunskap om en viss variabel inte nödvändigtvis ger området där insatser bör tillsättas. Vidare, genom att föra tillbaka multi-kausalitet till den vetenskapliga debatten, erbjuder avhandlingen nya vägar för hypotesprövning och teoriutveckling inom vår gemensamma strävan att förstå Naturen. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 2: Manuscript. Paper 4: Manuscript.</p>
65

Valuation of environmental impacts and its use in environmental systems analysis tools

Ahlroth, Sofia January 2009 (has links)
Valuation of environmental impacts in monetary terms is a both difficult and controversial undertaking. However, the need to highlight the value of ecosystem services in policy decisions has become more and more evident in the face of climate change and diminishing biodiversity in the sea and other ecosystems. Valuing non-market goods and services, like ecosystem services, is a lively research field within environmental economics, and valuation methods have been considerably elaborated in the last ten years. In practical policy analyses, there is often a need for readily available valuations of different impacts. This thesis explores and develops several ways to include valuation of environmental impacts in different policy tools, such as cost-benefit analysis, environmental accounting and life-cycle analysis. The first paper in this thesis is a part of the Swedish attempts to construct and calculate an environmentally adjusted NDP (net national product). This work involved putting a price on non-marketed environmental goods and assets. The valuation methods used in paper I include many of the available methods to value non-marketed goods and services. Valuation of environmental impacts and/or environmental pressures is used in a number of environmental systems analysis tools besides environmental accounting. Examples are Cost-Benefit Analysis, Life Cycle Assessment, Life Cycle Cost analysis, Strategic Environmental Assessment and Environmental Management Systems. These tools have been developed in different contexts and for different purposes; the way valuation is used also differs. In paper II, the current use of values/weights in the tools is explored, as well as the usefulness of a common valuation/weighting scheme and necessary qualities of such a scheme. In the third paper, a set of generic weights meeting these criteria is developed. Some of the generic values in the weighting set are taken from directly from other studies, while some are calculated by applying a benefit transfer method called structural benefit transfer on results from selected valuation studies. The method is tested on a number of valuation studies in the fourth paper. Climate change will have a significant impact on Sweden during this century, both positive and negative. In the fifth paper, a rough estimate of the impacts on man-made capital and human health is presented. The study is an example of an impact assessment including only marketed assets valued with market prices. In the last paper, the economics of sustainable energy use is discussed; what is a sustainable energy price, and how might growth be affected if energy use is limited to a sustainable level? The discussion is based on two different models of thought: a back-casting study, describing how a sustainable future society might look like, and economic scenarios projected with general equilibrium models. / QC 20100330
66

The Geography of Ecosystem Service Value: The Case of the Des Plaines and Cache River Wetlands, Illinois

Kozak, Justin Peter 01 January 2009 (has links)
The purpose of this study is to show the importance of the geography of demand in ecological economics and to provide guidance for future research efforts to incorporate it. The analysis examines gaps in the literature that deal with the spatial variability of potential beneficiaries to ecosystem services and demonstrates the quantitative importance of defining the geography of demand. Since ecosystem service value is anthropocentric, incorporating those who receive benefits into the economic accounting method is a necessary requirement. As the total benefits received from ecosystem functioning declines over space, so too does its economic value. There are two study areas in Illinois used in the analysis. The first is the Des Plaines River wetlands in the Chicago metropolitan area and the other is the Cache River wetlands in rural southern Illinois. This study finds large ranges of value for ecosystem services when the decay of value over space is incorporated. Also, these findings suggest a minimum spatial requirement depending on the scale of aggregation. For a county level scale, a minimum economic jurisdiction of 1,000 km is suggested. Finally, the presence of large numbers of beneficiaries near an ecosystem has the greatest influence on value when the economic jurisdiction is spatially limited. From the steepest distance decay function to the shallowest the Des Plaines wetlands returned a range of values from approximately $971,000 to $2.3 billion and the Cache wetlands values ranged from $0 to $2.5 billion. This paper is not intended to be a case study for the economic valuation of a specific area but rather a demonstration of the necessity for a spatial economic framework that accounts for the delivery and receipt of ecosystem services over space.
67

Ocean acidification and warming impacts on native and non-native shellfish : a multidisciplinary assessment

Lemasson, Anaëlle J. January 2018 (has links)
Ocean acidification and warming have been shown to affect a wide range of marine organisms and impact assemblages and ecosystems. Many of the species experiencing negative biological effects provide valuable ecosystem services, yet it is unclear how these biological effects will affect ecosystem services provision. This thesis aimed to appraise the consequences of ocean acidification and warming on important shellfish species, from physiology to provision of ecosystem services, using a multidisciplinary approach. The responses to ocean acidification and warming of two ecologically and commercially important species of oysters – the native European Flat oyster Ostrea edulis, and the non-native Pacific oyster Magallana gigas – were assessed in laboratory mesocosms following long-term exposures to a range of scenarios predicted for 2050 and 2100. Oysters provide numerous ecosystem services, including improvement of water quality, reef formation, and food provision, but are at risks from ocean acidification and other stressors due to negative impacts occurring at multiple life-stages and threatening reef maintenance and functioning (Chapter 1). The physiology of adult oysters appeared susceptible to ocean acidification and warming, with evident sub-lethal effects (Chapter 2). Magallana gigas experienced a greater degree of stress than O. edulis, displaying increased Standard Metabolic Rate, reduced Clearance Rate, and poorer Condition Indices. Reductions in Clearance Rates of M. gigas are especially concerning and may have important ecological impacts by limiting their ability to improve water quality in the future. The physiological changes experienced by individual oysters held important implications for the functioning of the reefs through changes in predation resistance. Again, M. gigas appeared to undergo more pronounced changes than O. edulis, displaying increased muscle strength but weakened shell strength. These changes are expected to alter its susceptibility to predators and influence community level interactions. Both O. edulis and M. gigas also underwent important changes to their biochemical composition with trends for impoverished nutritional quality, which holds direct implications on the provision of sea food. In particular, M. gigas contained lower lipid, carbohydrate, and protein levels, but higher contaminant concentration (copper); this change holds concerns for both future food security and future food safety. It was apparent that the physiological stress experienced (Chapter 2), led to significant energy reallocation from somatic growth to metabolism by depleting energetic reserves (Chapter 4), at the detriment of its nutritional quality. No negative effects on the eating quality of M. gigas (appearance, aroma, texture, taste, and overall acceptability) were recorded following a short-term exposure to ocean acidification and warming (Chapter 5), which was considered positive for the aquaculture sector. In order to secure future food provision and economic revenue, the UK aquaculture industry might need to reconsider its management strategy in the future, and encourage the production and consumption of O. edulis, in addition to the already popular M. gigas. It is clear that the impacts of ocean acidification and warming on oysters are multifaceted and occurring at multiple scales and levels of organisation. The risks to oysters and oyster reefs appear species-specific; in the UK, introduced M. gigas may be more vulnerable than native O. edulis. To secure benefits and minimise costs related to the management of introduced species, these findings could be integrated into the current management and conservation measures in place for these species and the reefs they can form.
68

Matching scales : the impact of ecosystem service scales on a planning and policy environment

Holden, Anastasia January 2016 (has links)
There is an increase in the consideration of ecosystem services (ES) within the planning, policy, and research sectors. The increase in sectors working with ES is leading to an increase in scale mismatches, where ecosystem services are being mismanaged, leading to problems. Using a combination of methods these scale issues were investigated. A systematic review of both scientific and grey literature was undertaken which analysed 112 documents and led to a survey of 72 subjects who were working with ES across different sectors, and finally 19 in-depth interviews were undertaken, in order to understand fully the scale issues, and potential solutions being used. The systematic review found that a lot of ecosystem service scientific literature was based on, or had connections with, the global issue of climate change, this was in contrast to the survey that found that both researchers and those in policy are working at a regional spatial scale or below. The in-depth interviews attributed this to many factors including the pressure to publish in high-impact journals, and applying for funding. The survey found that the different sectors are working at different scales, and where they do work at the same scale, the definition they place on that scale term is different. The survey and in-depth interviews found that funding can influence the extent of a project and funding timelines lead into the temporal scale of a project. Funding can encourage collaboration with stakeholders and between sectors in order to pool resources and expertise. Alongside clarity of terms used and expectations for the project, collaboration was also put forward as one of the methods which can alleviate scale mismatches.
69

A importância dos habitats naturais no entorno de plantações de cajueiro anão precoce (Anacardium occidentale L.) para o sucesso reprodutivo / The importance of natural habitats in the surrounding area plantations dwarf cashew (Anacardium occidentale L.) reproductive success

Flores, Lilian Maria Araújo de January 2012 (has links)
FLORES, Lilian Maria Araújo de. A importância dos habitats naturais no entorno de plantações de cajueiro anão precoce (Anacardium occidentale L.) para o sucesso reprodutivo. 2012. 44 f. Dissertação (Mestrado em ecologia e recursos naturais)- Universidade Federal do Ceará, Fortaleza-CE, 2012. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-05-24T17:50:51Z No. of bitstreams: 1 2012_dis_lmaflores.pdf: 1439184 bytes, checksum: 2c8f58333da51b8133cf592613637010 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-05-27T20:39:33Z (GMT) No. of bitstreams: 1 2012_dis_lmaflores.pdf: 1439184 bytes, checksum: 2c8f58333da51b8133cf592613637010 (MD5) / Made available in DSpace on 2016-05-27T20:39:33Z (GMT). No. of bitstreams: 1 2012_dis_lmaflores.pdf: 1439184 bytes, checksum: 2c8f58333da51b8133cf592613637010 (MD5) Previous issue date: 2012 / The expansion of the agriculture has led to the changes in the natural habitat and the reduction of pollinators. The cashew (Anacardium occidentale L.) is an economically important cultivated crop in Northeastern Brazil due to its nut, oil and cashew apple production. However, changes in the landscape may have been causing low fruit set. Our aim was to assess the importance of natural habitats conservation to the provision of pollinators to cultivated cashew orchards. To do so, we observed the importance of the natural areas on the abundance and richness of the floral visitors and the effect of these interactions on the cashew’s reproductive success. We carried out the study in the municipality of Horizonte, Ceará, from July to December 2011. We collected all floral visitors and reported the fruiting rate (fruit/flower ratio) in cashew crops near fragments of native vegetation at different distances. Our results show that the cashew relies on visiting insects for fruit set. Bees and wasps were the main visitors, with the former being the most frequent. Also, the quality of the natural habitat has great influence on the number of species and density of the visitors in the orchard. Our findings show the importance of ecosystem services to these cultivated cashew orchards. / A expansão da agricultura tem levado à alteração nos habitats naturais e à drástica redução de polinizadores. Uma cultura economicamente importante para o nordeste do Brasil é o cajueiro (Anacardium occidentale L.) devido à sua produção de castanha, óleo e pseudofruto. Entretanto, as alterações na paisagem podem estar ocasionando baixo rendimento em sua frutificação. Este trabalho teve como objetivo discutir a importância da conservação de habitats naturais para o fornecimento de polinizadores ao cajueiro cultivado. Para alcançar este objetivo, experimentos foram realizados a fim de observar a importância dos habitats naturais no entorno de plantações de cajueiro para a abundância e a riqueza de visitantes florais e consequentemente para o sucesso reprodutivo do cajueiro. O estudo foi desenvolvido no município de Horizonte – CE entre julho e dezembro de 2011, em plantios de caju próximos a fragmentos de vegetação nativa. Foram coletados todos os visitantes florais do cajueiro a diferentes distâncias do habitat natural. Os principais grupos coletados foram abelhas e vespas, com frequência de visitação significativamente maior das abelhas. Foi observado o percentual de frutificação (razão fruto/flor), onde o cajueiro demonstrou dependência dos insetos polinizadores para a produção de frutos. Como resultado, a qualidade do habitat natural apresentou influência sobre o número de espécies e a densidade dos insetos visitantes do plantio, demonstrando a importância dos serviços prestados pelo ecossistema a esses plantios de caju.
70

Improving projections of change in the ecosystem services of West Africa

Hartley, Andrew James January 2016 (has links)
Ecosystem services are the benefits people obtain from ecosystems. Quantifying these benefits and understanding how they may change under multiple future pressures, such as climate change or land use change, is a highly uncertain exercise. In managing ecosystems to be resilient to future changes, natural resource managers need the most accurate information available, but also need to be informed of when and where they can be confident, or not, in projections of change. In this thesis, I address many of the key aspects of uncertainty in projections of change in ecosystem services, with a particular focus on challenges in West Africa. I show where and for what variables climate models may be reliably used in ecological studies, providing important advice for interpreting the impacts of climate change on biodiversity. Furthermore, I show that uncertainty in climate observations can also have a significant impact on climate change adaptation decisions at both the species level and in terms of protected area management. I also address how vegetation in West Africa may respond to future climate change. I found that even after uncertainties in climate and land use were considered, carbon storage in West African tropical forests was projected to increase where forest degradation remained low or reduced; vegetation productivity was projected to increase in all parts of West Africa, with the exception of locations in the West Sahel where the largest reductions in precipitation were projected; and, importantly for protected areas, ecosystems were projected to shift northwards despite uncertainty in precipitation projections. I also show the sensitivity of 3 major land surface models to uncertainty in vegetation mapping, thereby providing guidance to the remote sensing community on priorities to improve land cover mapping and to the earth system modelling community on bounds of uncertainty in carbon, moisture and energy budgets due to vegetation mapping uncertainties. Lastly, in using the latest land-atmosphere coupled convection-resolving model, I show that it is possible to simulate the observed interaction between landscape heterogeneity and local and regional scale precipitation in West Africa. This provides a timely and relevant tool that will allow scientists and natural resource managers to more accurately assess the impact of changes in land use on the regional climate of West Africa.

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