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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

Itämeren rehevöitymisen uudistettu diagnoosi ja paradigma

Lappalainen, K. M. (K. Matti) 01 June 2018 (has links)
Abstract The eutrophication of the Baltic Sea continues despite decrease of the external phosphorus load by as much as 80% of the target confirmed by HELCOM. The aim of this thesis is to investigate this paradox, critically evaluate previous explanations for the persistent eutrophication, and to introduce a new diagnosis and paradigm for the causes and processes behind eutrophication of the Baltic Sea. According to the current consensus, anthropogenic nutrient loading is nearly the sole cause of eutrophication and regular cyanobacterial blooms. However, this study shows that the areal phosphorus loading rate, when modeled properly, is surprisingly low, and unlikely to be the primary cause of eutrophication. Instead, the frequency of the salt water pulses has decreased dramatically during the past 40 years. This is the root cause of eutrophication, via the hyper-vicious cycle of the hypoxic and finally anoxic conditions of the deeps causing internal phosphorus loading, denitrification, and nitrogen and carbon fixation. Furthermore, this work confirms that nitrogen fixation increases in low nitrogen conditions, further increasing eutrophication and cyanobacterial blooms. Thus, the most effective way to break the cycle of eutrophication is to improve the oxygen conditions of the deeps, which really is impossible to achieve by decreasing external loading alone. A key result of this work is that natural processes, rather than human activity, plays a decisive role in the eutrophication process – a perspective that typically faces substantial resistance. This thesis discusses how sociological and political views have affected the scientific community and its pursuit to model the mechanisms of eutrophication of the Baltic Sea. In conclusion, this study leads to important novel insights by providing new models for calculating the external and internal phosphorus loads of the Baltic Sea, with results highlighting the importance of natural processes of internal loading from the anoxic deeps. Altogether, this thesis introduces a new a paradigm for eutrophication of the Baltic Sea. / Tiivistelmä Itämeri rehevöityy edelleen, vaikka fosforikuormitusta on vähennetty 80 % tavoitellusta. On siis syytä tutkia miksi Itämeren tila ei ole parantunut. Syntyneen ristiriidan ratkaisemiseksi tarkoituksena on etsiä aiemmista tulkinnoista ristiriitoja, korjata ne ja uudistaa tietopohja uudeksi ja toimivammaksi paradigmaksi. Virhetulkintojen tunnistamiseen sovelletaan Popperin falsifikaatiomenettelyn periaatteita. Konsensuksen mukaan ihmisperäinen kuormitus on lähes yksinomainen syy (sinilevä)rehevyyteen. Kuitenkin Vollenweiderin mallin mukaan tehty, hydrologialla painotettu fosforin pintakuormitus on ollut 1970 - 1980-luvuilla vain lievää rehevyyttä edellyttävällä tasolla. Ulkoinen kuormitus ei siten voi olla suurin rehevyyden aiheuttaja. Sinilevärehevyyttä ylläpitävänä päätekijänä on syvävesiin happea tuovien suolavesipulssien toistuvuuden romahtaminen. Siitä syntyneet syvävesien ja -pohjien hapettomuudet aiheuttavat Gotlanninmeressä sekä sisäistä kuormitusta että lisärehevöittävää typen- ja hiilensidontaa. Yhdessä näitä prosesseja nimitetään nyt supernoidankehäksi. Johtopäätöksiä: • Ihmistieteelliset ja ympäristöpoliittiset näkemykset vaikuttavat luonnontieteellisiin tulkintoihin luultua enemmän. • Suolavesipulssien harventuminen on hapettomuus- ja rehevyyskierteen perussyy. • Syvänteiden hapettomuus on kaikkialle negatiivisesti säteilevä keskeistekijä. • Itämeren supernoidankehä on purettava saattamalla syvänteet hapellisiksi. • Hapellisuutta ei voida saada aikaan ulkoisen kuormituksen vähentämisellä. • Jäljelle jäävät siten teknologiset keinot, joista toteutuskelvollisimmalta näyttää Itämeren hapellisimman ja kylmimmän veden pumppaus 30 metrin syvyydestä syvänteisiin, mikä tehostaa myös pulssivesien virtausta syvänteiden pohjalle. Tämä väitöskirja sisältää viisi vallitsevasta paradigmasta poikkeavaa tulosta: 1. Itämerelle on kehitetty rehevyyden uusi diagnoosi ja paradigma, 2. Luonto dominoi Itämeren tilaa, ei ihminen, 3. Typensidonnalla on lisärehevöittävä mekanismi, 4. Itämerelle on kehitetty uusi fosforin sisäkuormituksen laskentamenetelmä, 5. Virtuaalisen fosforikuormituksen laskenta. Ilman Gotlanninmeren syvänteiden hapellisuutta Itämeri on tuomittu pysymään rehevyyden supernoidankehässä, ’kaksinkertaisessa takalukossa’.
72

The potential for community-based natural resource management (CBNRM) affiliated with BC's Protected Area System

Rozwadowska, Anna 20 December 2010 (has links)
Community-based natural resource management (CBNRM) related to protected areas (PAs) originated in the 1980’s in Zimbabwe, Africa, in the buffer zone communities of Africa’s National Parks. CBNRM attempted to address the problems associated with colonial, protectionist style ‘fence and guns’ conservation management approaches, which excluded resource-based communities from conservation areas. CBNRM attempts to meet the biodiversity conservation objectives of conservation areas, and the sustainable development and livelihood objectives of neighbouring communities. While CBNRM initiatives have been well documented internationally over the past decades, little is known about the status of CBNRM within Canada. In order to bridge this knowledge gap and to link trends in conservation and protected areas management internationally to Canada and to British Columbia (BC), this thesis examines the potential for community-based natural resource management (CBNRM) affiliated with BC's Protected Area System. “Potential” is determined by comparing the situation in BC to the international CBNRM experience. The study draws on a sample of Conservancies from the categories of the BC Protected Area (PA) System, focusing particularly on the nine Sea-to-Sky Land and Resource Management Plan (LRMP) Area Conservancies and neighbouring First Nations communities: Squamish, L’il’wat and In-SHUCK-ch. Information has been obtained through interviews (guided by semi-structured questionnaires) conducted with BC government informants and First Nations representatives, supplemented by key documents. The questionnaire examined the potential for CBNRM according to a.) the community's perspective: potential (costs and) benefits of the protected area, including goods and services, cultural and social benefits and sustainable economic development opportunities provided by the protected area; and benefits of community involvement in natural resource management and protected area governance; and b.) the conservation perspective: benefits through community cooperation in biodiversity conservation within the targeted protected area. Other factors that have been identified through the international experience to affect CBNRM initiatives, such as use regulation; tenure; policies and legislation; awareness of and support for the protected area; and community capacity were thoroughly examined across all sources of information. This study finds that there is potential for CBNRM affiliated with the BC PA system in protected area designations such as ‘Conservancies’. Potential relates to the role of CBNRM in biodiversity conservation, meeting the aspirations of BC’s First Nations communities, and in recognizing First Nations as legitimate stakeholders in protected areas and conservation management. As in the international experience, numerous social, political, economic and other factors present opportunities and challenges to the adoption of CBNRM in BC. This thesis concludes with key recommendations for protected areas and conservation management in BC and Canada and identifies opportunities to further explore key topic areas that arose from the research findings.
73

Human capital formation and the American Dust Bowl

Arthi, Vellore January 2016 (has links)
I use variation in childhood exposure to the Dust Bowl, an environmental shock to health and income, as a natural experiment to explain variation in adult human capital. I also examine a variety of mechanisms by which the Dust Bowl influenced later-life wellbeing, and investigate the scope for recovery from this early-life shock. I find that exposure to the Dust Bowl in childhood has statistically significant and economically meaningful adverse impacts on later-life outcomes, for instance, increasing disability and reducing fertility and college completion. These results hold even after accounting for the possibly confounding effects of the Great Depression, migration, and selective fertility or mortality. The effects I find are more severe for those born in agricultural states, suggesting that the Dust Bowl was most damaging via the destruction of agricultural livelihoods. This collapse of farm incomes, however, had the positive effect of increasing high school completion amongst the exposed, likely by reducing the demand for child farm labor where such labor was not essential to production, and thus decreasing the opportunity costs of secondary schooling; in this outcome, unlike in college completion, family income and student ability were irrelevant. Many of the worst adverse effects are found amongst those exposed prenatally and in early childhood, suggesting that congenital complications in capability development, together with low parental incomes in utero and thereafter, may be to blame for such later-life disadvantage. Together, these findings imply that the Dust Bowl acted largely "indirectly," as an economic shock that in turn affected in utero and early-life conditions, rather than "directly," through personal exposure (e.g. dust inhalation) in childhood. Lastly, results - particularly those on New Deal expenditure - imply both that remediation from early-life disaster is possible under the right circumstances, and that post-shock investment may have compensated for rather than reinforced damage to child endowments. The findings in this study are consistent with a multi-stage model of human capability formation, in which investments in one period respond to endowments in a previous one, and may either reinforce or compensate for these endowments.
74

Diskurs trvale udržitelného rozvoje a jeho dopad na odbornou veřejnost / The Discourse of Sustainable Development and its Impact on Academic Public

BUCHTELE, Roman January 2018 (has links)
The aim of this diploma thesis is to determine, whether the discourse of sustainable development (SD) has any impact on the academic public concerning the knowledge of the topics and principles of SD, or whether it has impact on the value orientation. A group of university students of economics was chosen for the purposes of this thesis as an instance of the academic public. The thesis consists of two main parts: the theoretical part and the analytical part. The theoretical part defines the theoretical base of following topics: the development of the human attitude towards the Earth; the warning messages that preceded the revolutionary year 1987; the basis of the sustainable development; selected topics and principles of the environmental pillar of sustainability; the environmental education; environmental sociology and the new environmental paradigm. The methods applied in the analytical part of this thesis are based on the quantitative approach, NEP and HEP, the environmental sociology. The overview of the discourse of SD from the point of view of the environmental pillar allows for the specific research the operationalization of the knowledge of the topics and principles of SD including the readiness to use those principles.
75

Identidade ambiental metropolitana como instrumento à governabilidade / Environmental metropolitan identity as a tool to governance

Batata, Adriane Gomes Rodrigues, 1970- 19 August 2018 (has links)
Orientador: Leila da Costa Ferreira / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-19T13:27:21Z (GMT). No. of bitstreams: 1 Batata_AdrianeGomesRodrigues_D.pdf: 2882397 bytes, checksum: 7f8ac090d609411355459d45721f63fc (MD5) Previous issue date: 2011 / Resumo: Os conflitos de âmbito ambiental-urbano têm sido apontados como um dos grandes desafios à governabilidade metropolitana devido, principalmente, a ausência de canais que possibilitem legitimar estratégias e instrumentos que ajudem a superar as desigualdades intrametropolitanas e a obter acordos, principalmente em países federalistas como o Brasil. Contudo, algumas instituições têm implementado novos arranjos entre atores políticos, econômicos e sociais que possibilitam a obtenção de acordos de caráter ambiental entre os municípios que constituem espacialidades intermediárias - entre o estado e o município - como as regiões metropolitanas. Esses arranjos buscam promover o desenvolvimento e/ou a qualidade de vida de determinada região e são estruturados a partir de interesses comuns específicos aos municípios que constituem essa mesma região podendo, em alguns casos, estimular a formação de uma identidade ambiental. Enfim, a partir da hipótese de que as instituições responsáveis por criar/ampliar os canais de governabilidade em questões ambientais podem identificar ou construir identidades ambientais metropolitanas, e que a existência de uma identidade ambiental específica a cada região resulta em diversificados modelos de governabilidade para uma mesma questão ambiental entre diferentes regiões, o trabalho investiga a existência de identidade ambiental em regiões metropolitanas e sua influência na governabilidade de questões urbano-ambientais e na qualidade ambiental dessas regiões. Para buscar evidências que possibilitam responder aos questionamentos propostos foi aplicada junto a duas regiões metropolitanas paulistas e instituições correspondentes uma metodologia elaborada a partir de conceitos como Urbanização, Metropolização, Sociedade de Risco/ Vulnerabilidade Sócio-Ambiental, Capital Social. Os resultados obtidos possibilitam responder parcialmente aos questionamentos, mas apontam novas perspectivas ao estudo da governabilidade metropolitana em questões ambientais através da percepção/identificação/construção de identidades / Abstract: Conflicts within the urban environment have been hailed as a major challenge to the metropolitan governance, mainly due to the absence of channels enabling the legitimation of strategies and tools to help overcome the intra-metropolitan inequalities and reach agreements, especially in federalist countries like Brazil. However, some institutions have implemented new arrangements among political economic and social actors, which enable the achievement of an environmental nature of agreements between the municipalities that are intermediary spatialities - between the state and municipality - as the metropolitan areas. These arrangements seek to promote the development and/or quality of life of a given region and are structured around common interests that are specific to municipalities which constitute this same region, and may in some cases stimulate the creation of an environmental identity. Finally, based on the assumption that the institutions responsible for creating/expanding the channels of governance on environmental issues can identify or build environmental metropolitan identities, and that the existence of a specific environmental identity for each region results in diverse models of governance for a same environmental issue between different regions, the paper investigates the existence of environmental identity in metropolitan regions and their influence on the governance of urban environmental issues and on the environmental quality of these regions. To search for evidence to answer the questions proposed, a methodology developed from concepts such as urbanization, metropolization, society of risk/socio-environmental vulnerability, social capital, was applied to two metropolitan regions of São Paulo and corresponding institutions. The results allowed to partially answer questions, however, they point out new perspectives to the study of metropolitan governance in environmental issues through awareness/identification/construction of identities / Doutorado / Ambiente e Sociedade / Doutor em Ambiente e Sociedade
76

A Multidisciplinary Approach to Restoration of Butternut (Juglans cinerea)

Andrea N Brennan (9390080) 16 December 2020 (has links)
<div>Anthropogenically driven global change is disrupting ecosystems and habitats of many plant species, straining the ability of native species to survive and reproduce. The overarching goal of this research was to holistically work towards restoration of a threatened tree species by connecting research from different disciplines. In order to do so, the threatened butternut tree (<i>Juglans cinerea</i>) and its hybrids were used as a case study. Hybridization can incorporate stress tolerance in plants and could be a potential restoration tool. Evidence in some wild butternut populations indicates that naturalized hybrids of butternut with Japanese walnut (<i>Juglans ailantifolia</i>) may be more tolerant to butternut canker disease (BCD) than butternut, but this has not been formally tested. Thus, chapter 2 examined potential BCD tolerance within and between unadmixed and hybrid butternut inoculated with two BCD fungal isolates. Differences in canker growth were observed by fungal isolate, which could help to explain some differences in BCD severity found among butternut populations. Smaller and fewer cankers and greater genetic gains were detected in hybrid families, demonstrating that hybrids warrant further evaluation as a possible breeding tool for developing BCD-resistant butternut trees.</div><div>However, even with increased disease tolerance, hybrids must possess similar ecophysiological tolerances to their native progenitor to be an effective replacement. Butternut is extremely cold hardy, but Japanese walnuts are native to a warmer ecosystem, indicating potential disparities in extreme temperature tolerances between the two species and their hybrids. Thus, samples from mature trees were subjected to cold and heat treatments to compare relative extreme temperature tolerances within butternut and between butternut, Japanese walnut, and their hybrids. Within butternut, trees from colder areas exhibited less cold damage than those from warmer areas. Differences in heat damage among provenances occurred but did not follow a clear trend. Butternut exhibited greatest cold tolerance, Japanese walnut exhibited greatest heat tolerance, and hybrids were intermediate. Thus, the utility of hybrids for restoration could be limited at the extremes of the species’ distributions.</div><div>A second, but different type of freeze test was conducted for chapter 4 using seedlings to gain a more nuanced understanding of cold tolerance within butternut and between butternut and its hybrids. No survival or damage differences were detected in butternut provenances, although seedlings from the coldest provenances experienced more delayed budbreak at the two warmest treatments than those from warmer provenances. Interspecific differences were not observed in dieback but were detected in survival and budbreak. The hybrids had greater survival than butternut from warmer provenances at the lowest temperature treatment (-38 °C), but given that temperatures that low are extremely unlikely to occur in those provenances, it is not anticipated to give the hybrids an advantage if planted in those areas. However, the hybrids’ earlier budbreak could limit the success of restoration with these hybrids in the coldest extents of butternut’s range. </div><div>If hybrids, as well as genetically modified (GM) trees, are successfully developed for effective disease tolerance and to serve as an ecologically suitable replacement, success of restoration using hybrids will ultimately depend on those directly responsible for replanting efforts. A survey was administered to land managers in 46 organizations in Indiana to gauge perceptions of hybrid and GM trees, as well as current use of hybrid trees. Land managers had stronger concern for ecological, rather than economic, issues. Agreement was highest for using hybrid and GM trees for “conservation and restoration of at-risk species”, “timber production”, and “non-timber products (fruit, syrup, etc.)”. However, perceptions varied by characteristics, such as concern type, age, and the type of land they managed. Ecological concern and the type of land being managed most strongly predicted current hybrid use. Overall, results indicate the majority of land managers in Indiana would likely be agreeable to recommendations towards using hybrids. However, most nonetheless had strong ecological concerns about their suitability as a native replacement. It is important to note, though, that consistent with the results of previous studies, great variation was seen within the performance and characteristics of the butternut hybrids in chapters 2-4. Thus, it may be possible with careful selection and breeding to harness this variation to develop disease tolerant and ecologically similar hybrids acceptable to land managers.</div>
77

Towards an Ontology and Canvas for Strongly Sustainable Business Models: A Systemic Design Science Exploration

13 September 2013 (has links)
An ontology describing the constructs and their inter-relationships for business models has recently been built and evaluated: the Business Model Ontology (BMO). This ontology has been used to conceptually power a popular practitioner visual design tool: the Business Model Canvas (BMC). However, implicitly these works assume that designers of business models all have a singular normative goal: the creation of businesses that are financially profitable. These works perpetuate beliefs and businesses that do not create outcomes aligned with current natural and social science knowledge about long term individual human, societal and ecological flourishing, i.e. outcomes are not strongly sustainable. This limits the applicability and utility of these works. This exploratory research starts to overcome these limitations: creating knowledge of what is required of businesses for strongly sustainable outcomes to emerge and helping business model designers efficiently create high quality (reliable, consistent, effective) strongly sustainable business models. Based on criticism and review, this research project extends the BMO artefact to enable the description all the constructs and their inter-relationships related to a strongly sustainable business model. This results in the Strongly Sustainable Business Model Ontology (SSBMO). To help evaluate the SSBMO a practitioner visual design tool is also developed: the Strongly Sustainable Business Model Canvas (SSBMC). Ontological engineering (from Artificial Intelligence), Design Science and Systems Thinking methodological approaches were combined in a novel manner to create the Systemic Design Science approach used to build and evaluate the SSBMO. Comparative analysis, interviews and case study techniques were used to evaluate the utility of the designed artefacts. Formal 3rd party evaluation with 7 experts and 2 case study companies resulted in validation of the overall approaches used and the utility of the SSBMO. A number of opportunities for improvement, as well as areas for future work, are identified. This thesis includes a number of supplementary graphics included in separate (electronic) files. See “List of Supplementary Materials” for details.

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