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Effects of Watershed and Habitat Conditions on Stream Fishes in the Upper Roanoke River Watershed, VirginiaStancil, Vann Franklin 18 July 2000 (has links)
I collected fish samples and habitat data at 43 sites throughout the upper Roanoke River watershed, Virginia. Sites were separated into three watershed areas size classes: 10 - 15, 20 - 30, and 70 - 80 km². I correlated physical in-stream conditions with proportions of forest, disturbed, and herbaceous/agricultural land at various watershed-scales to determine factors affecting stream habitat. I grouped fishes into metrics commonly used in indexes of biotic integrity and created a multimetric index called the mean metric score to represent fish communities at sites. Fish variables and metric values were compared with stream habitat and watershed variables to determine primary influences on fish communities. I correlated land use at 24 spatial scales, which differed by buffer width and stream network area, with mean metric scores to determine zones of greatest influence on fish communities.
In-stream habitat conditions and amounts of forest, herbaceous/agricultural, and disturbed land varied greatly among sites. Habitat varied due to natural differences among sites, such as elevation and watershed area, and due to land use. Disturbed land use was greatest at lower elevations while forests were more abundant at higher elevations. Substrate size distribution was highly correlated with all three land use types at several spatial scales. Correlations between land use within various buffers and median particle size became stronger as larger proportions of watersheds were included in analysis.
Fish species richness increased from small to large sites by species addition. Species collected at small sites were also collected at large sites, but several species collected at large sites were absent elsewhere. For example, orangefin madtoms and bigeye jumprocks were only collected at three large sites. Fish distribution was a result of several factors such as watershed area, elevation, proportions of pools and of riffles, particle size, and land use within buffers and entire watersheds.
Sites with high mean metric scores were primarily limited to tributaries of the North and South Forks of the Roanoke River. Most sites with low mean metric scores were located near the cities of Roanoke and Salem. Forest and disturbed land use were highly correlated with mean metric scores. Elevation was also highly correlated with mean metric scores but herbaceous/agricultural land use was not. Correlations between percent forest within 24 buffers and mean metric scores were highest for small stream network areas and declined as more land farther from sites was included for analysis. Correlations between disturbed land use and mean metric scores were strong regardless of the area considered. Mean metric scores declined precipitously as disturbed land use within watersheds and buffers increased from 0 to 10 %, but reached a plateau at 10 to 20 % after which increases in disturbed land use did not result in lower mean metric scores.
My results suggest that species addition and ecological shifts from more generalized to more specialized species occur with increased stream size. Forested buffers are important for maintaining ecological integrity, and buffers along sites with adequate integrity should be candidates for riparian restoration. Future development should be concentrated in watersheds that are already developed and reforestation of riparian areas in developed watersheds may reduce the impacts of watershed-level disturbance. / Master of Science
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Migrationsmönster under 1800-talet : En fallstudie om migrationen till och från Kristinehamns stad under urbaniseringens första fas / Migration patterns during the 19th century : A case study on migration to and from the city of Kristinehamn during the first phase of urbanizationEdén, Sandra January 2022 (has links)
In this case study, migration to and from Kristinehamn during the years 1840, 1865 and 1866 is examined. This time period is characterized by significant changes in form of urbanization, increased communication opportunities, changed business legislation and an incipient industrialization. With help of moving lengths from the church archives in Kristinehamn, migration patterns will be mapped due to a quantitative method. Information concerning the migrants' age, titles and moving company is reported. Migrants are also categorized based on how far they moved and on how long they stayed in the city. The survey has elements of a qualitative method as interpretation of the results is made with support of existing migration theories and previous research. The aim of this study is to investigate how the migration patterns changed during this time and to seek reasonable explanations for the demographic changes that can be shown through migration trends. The results show that the migration patterns change, in various aspects, between the different investigated time periods. For example, the proportion of family migrants had increased, and the distance of migration was stretched in the later period. The findings in this study also point at differences in migration patterns due to social affiliation.
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Mining, dependence, and post-independence urbanisation in Botswana : sustainable development?Haynes, Michael J January 1990 (has links)
Bibliography: leaves 187-197. / Botswana has been considered as one of the few post-independence development successes in Africa. The country's recent status is attributable to the growth of the minerals sector, with diamonds and copper/nickel matte forming the basis of exports and government development revenues. Mining has not only been responsible for boosting export earnings, but has also stimulated most recent urbanisation, resulting in the some of the highest urban growth rates in sub-Saharan Africa. The problem of urban in-migration has been compounded by a bias in development expenditure, with the towns receiving a disproportionately large share of scarce resources. All new towns since independence have been established as service centres for the mines, with limited wider development occurring. Resultant vulnerability and instability in the urban sphere has been reflected in the case of Selebi-Phikwe, where a decline in the copper/nickel industry has threatened the future integrity of the town. That mining has not contributed towards development which is sustainable over the long terms calls into question, the resilience of Botswana's progress. A political-economic analysis of the development history of Botswana indicates a continuity between colonial neglect and the migrant labour system, and the current problems of dependence on the mining sector and external employment opportunities. The reasons for the dearth in diversified productive activity in mining towns in Botswana are related to an externally orientated development policy, with dependence on the world mineral markets. As the mining industry is based on the extraction of finite, non-renewable resources and is susceptible to fluctuations in mineral pricing, towns exclusively based on mining are latently unstable and have similarly finite lives. The problem is compounded by the lack of a local entrepreneurial class capable of stimulating the 'modern' sector which is related to the historical lack of an urban elite in the country. Given that there has been minimal associated development of productive opportunities outside of the primary sector in Selebi-Phikwe, the Government has instituted a crisis management strategy to deal with the situation. Proposals to diversify the economic base of Selebi-Phikwe are focused on attracting foreign investment, as a means of stimulating local, export-orientated industrialisation. As the incentives for locating in the town are primarily based on cheap, malleable, labour supplies, transnational investment is likely to be of a highly mobile nature and is unlikely to sustain employment and development in Selebi-Phikwe Certain conclusions are drawn from the experience of Selebi-Phikwe: Firstly, the problem of continuity in Selebi-Phikwe has historical roots indicating that short term panaceas are unlikely and that structural solutions are needed. Secondly, the town's fate holds important implications for the maintenance and support of the wider urban system in Botswana. Thirdly, expectations of indefinite economic prosperity have been generated in part, by continual Government emphasis on urban infrastructural development, something which is potentially problematic given the potential for urban discontinuity. A more rational evaluation of the urban sector in Botswana is required. With the precarious foundations of urbanisation in Botswana borne in mind, surplus revenues generated by mining should be channelled into rural employment creation rather than urban areas. An approach which treats the urban question in its entirety is required. There is thus a real need for a national development programme which integrates population and environmental policy with rural and urban sector planning, and which bases future development on the criteria of equity and sustainability.
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The Effects of Urbanization on Avian Seed Dispersal Success of Toxicodendron radicans (Anacardiaceae)Stanley, Amber M 01 August 2019 (has links)
Urbanization is increasing at a dramatic rate as the human population increases. While it is well-known that urbanization tends to decrease species diversity (i.e., biotic homogenization), it is not known how urbanization affects the frequency and efficiency of species interactions. Seed dispersal is a plant-animal interaction that depends on disperser feeding rate, disperser diversity, probability of seed dispersal and germination. How these factors are affected by urbanization however is unknown. In this study, we evaluate how urbanization alters these factors. Urban sites had 2x higher feeding rate and 3x higher number of disperser species. The probability of seed dispersal however was the same between natural and urban sites. Moreover, the probability of germination after dispersal was 20% lower in urban sites, leading to overall negative effects of urbanization on T. radicans seed dispersal. In this study we demonstrated that urbanization can affect species diversity, as well as their ecological functions.
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Architecture des services de communication dans un contexte de convergence / Towards a converged environment for communication servicesBertin, Emmanuel 11 December 2009 (has links)
Les services de communication de nouvelle génération doivent pouvoir coopérer pour répondre à des besoins spécifiques tout en gardant leur autonomie. Ceci nécessite de maîtriser leurs architectures et de partager ces architectures au sein de l'entreprise. Des cadres architecturaux communs sont alors indispensables. Après avoir fait le point des travaux sur ce sujet dans les domaines télécoms, web et IT, et après avoir discuté des enjeux de la convergence des services télécoms, nous introduisons ici quatre angles de vue (métier, fonctionnel, technique et applicatif), ainsi qu'une méthodologie pour construire des vues de référence partagées au sein d'une entreprise et des vues d'architecture propres à chaque service. Nous illustrons cette démarche à l'aide d'exemples et montrons ses applications pour construire des offres de service, pour rationnaliser les services existants et pour réaliser une convergence entre différents services. / Next-generation communication services should be able to cooperate in order to meet specific needs, while keeping their autonomy. This implies to master their architectures and to share these architectures within the enterprise. Architectural frameworks are therefore essential. After a review of the state of the art in the telecom, web and IT fields, and after having discussed the stakes of the telecom service convergence, we introduce here four viewpoints (business, functional, technical and applicative), as well as a methodology to build reference views that will be shared across the enterprise, and architectural views that are dedicated to each service. We illustrate this approach through case studies and we point out its applications to build service offers, to rationalize existing services and to realize a convergence between various services.
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Evaluating urban containment programsNelson, Arthur C. 01 January 1984 (has links)
Urban containment programs may be evaluated in terms of a theory unifying contributions from the economic, geographic and political science disciplines. The unified theory shows that successful programs will segment the urban-rural land market, remove speculative use value of rural land, and result in the urban land market valuing greenbelt proximity as an amenity. A general model to test urban containment programs against the unified theory is developed and then modified for application to Salem, Oregon. Results are fourfold. First, a gap in the locus of urban and rural land values at the UGB indicates that segmentation of the urban-rural land market is associated with urban containment policies. Second, the simultaneous effect of imposing a UGB proximate to urban development and subjecting rural land to conservancy zoning is to remove the speculative value component of rural land and reveal Sinclair's (1967) underlying convex quadratic agricultural use land value gradient. This finding is important in two respects: (a) it confirms the possibility of Sinclair's gradient, which has not been supported empirically hitherto, and (b) it suggests that a program's success in preserving greenbelt land solely for agricultural uses can be evidenced if Sinclair's gradient is revealed. Third, the conditions under which a program may fail to preserve rural land from speculative behavior will be evidenced by the traditional negatively sloping land value gradient. Fourth, where urban development is proximate to a UGB delineating greenbelts, the urban land market will value its proximity as an amenity. This finding is important in two respects: (a) it suggests that proximity to privately owned greenbelts may be valued as an amenity in the urban land market, a finding which has not been reported empirically hitherto, and (b) if an urban land market has confidence in the ability of an urban containment program to prevent sprawl into greenbelts, then it will treat greenbelt proximity as an amenity. The unified theory and methodology developed by this dissertation are generalizable to the evaluation of other urban containment programs.
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STUDY ON IMPACT OF URBANIZATION AND RAPID URBAN EXPANSION IN JAVA AND JABODETABEK MEGACITY, INDONESIA / インドネシア、ジャワ島とジャボデタベックメガシティにおける都市化と急速な都市拡大の影響に関する研究Andrea, Emma Pravitasari 24 September 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第19347号 / 地環博第140号 / 新制||地環||28(附属図書館) / 32349 / 京都大学大学院地球環境学舎環境マネジメント専攻 / (主査)准教授 西前 出, 教授 星野 敏, 教授 小方 登 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM
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The story exchange: narrative sharing as a catalyst for creative change in Orange GroveRusso, Tatum January 2017 (has links)
Thesis is submitted in partial fulfilment for the degree of Master of Architecture (Professional) to the Faculty of Engineering and the Built Environment, School of Architecture and Planning at the University of the Witwatersrand, Johannesburg, 2017 / Ever since we as humans sat around fires in caves, we have been sharing stories in an attempt to understand life and the need to survive. Storytelling is an integral part of human experience. We define our lives in narrative form. It gives us a means to explain the inexplicable and understand our lives in the context of a greater whole. The increasing prevalence of technologies like cell phones, tablets, and laptops has lead to a phenomenon of disconnection between people in the physical dimension. Instead of communicating faceto-face, with all of our senses engaged, we rely on technology to interact with friends and share our stories. South Africa’s current political climate, and particularly the protests on University campuses across the country in the past year, has emphasised the idea that society is suffering from a lack of real communication. This research proposes that stories can create change in the built environment, through building design, in the same way that stories affect our personal beliefs and understanding. Thus the concept of narrative and memory and how it manifests itself in architectural design and discourse is explored. This report finds that nostalgia and phenomenology play a significant role in producing connections between people and the built environment and these theories must be employed to create strong narratives in architecture.
Orange Grove, once a vibrant suburb along Louis Botha Avenue, has suffered from a lack of investment and development since the 1990s. Ultimately I employ perceptual and conceptual design philosophies to design a sustainable intervention within the already rich context of Orange Grove. The Story Exchange building design proposes that only through art, craft and open tactile interaction (that involves all the senses) - can one produce architecture that becomes a catalyst for the creative upliftment of the area and its community. / XL2018
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Israel’s Long and Winding Road to a Second Demographic Transition : A Study on Attitudes in Accordance with the Second Demographic Transition in Israel 2009-2019Bar-On, Yonatan January 2023 (has links)
This cross-sectional study focuses on attitudes in accordance with the Second Demographic Transition (SDT) in the adult population of Israel. Such attitudes are expressed by favoring an establishment of a family at older ages and favoring a small family size. Such attitudes are also expressed by supporting certain forms of living arrangements that are alternative to marriage. Based on results from Israel’s Social Survey (ISS), it seems that during 2009-2019, there was a nationwide rise in support of attitudes in accordance with the SDT. This trend is well apparent, despite a moderate decline in support of divorce as the best solution in insolvable relationships. In addition, it was found that the level of religiosity had a substantial and negative effect on the probability of supporting attitudes in accordance with the SDT. Furthermore, the type of residence (i.e., living in an urban environment) had no substantial effect on the probability of supporting these attitudes. Additionally, although differences in support of these attitudes were found between residents of Jerusalem and Tel-Aviv, they were less consistent and substantial after the effects of religious affiliation and religiosity were considered. However, residing in Tel-Aviv had substantial and positive effects on the probability of accepting unmarried couples’ parenthood and on the probability of preferring establishing a family for women aged 30 and above. This study also points out that certain attitudes are more supported by Jews, while others are more supported by Muslims.
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The Impact of Urbanization on Painted Turtle (Chrysemys picta) BehaviourBlanchett, Sebastian 21 June 2023 (has links)
Urbanization is one of the major causes of the global biodiversity crisis with reptiles being particularly vulnerable, due to factors such as habitat loss and road mortality. Behaviour plays a crucial role in determining the success of urban animals, but behavioural responses to urbanization are rarely studied in reptiles. I studied the differences in aggression, boldness, and exploration in painted turtles (Chrysemys picta) living in urban and undisturbed areas. I hypothesized that aggression, boldness, and exploration would increase in urban painted turtles. I studied painted turtles from 24 sites across an urban to undisturbed gradient in Ottawa, Ontario, Canada over the summers of 2021 and 2022. I captured turtles with hoop nets and tested their behaviour in the field, and the repeatability of their behaviour in the laboratory. I found that urbanization had a statistically significant, positive effect on painted turtle aggression and boldness, and no effect on exploration. Overall, I determined that urbanization is affecting painted turtle behaviour, but further research is required to better understand the factors behind this.
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