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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.
21

White-tailed deer (Odocoileus virginianus) population dynamics in a multi-predator landscape

Duquette, Jared Fitzgerald 15 August 2014 (has links)
Indices of white-tailed deer (Odocoileus virginianus) abundance in the western Upper Peninsula of Michigan suggested the population declined 40% from the previous 5 year mean following 2 consecutive severe winters in the mid-1990s and has not since increased in population size. I collected estimates and assessed biological and environmental covariates of survival and recruitment of fawns (< 1 year old) and age-specific reproductive and survival rates of adult females (> 1.6 years old) in the southwestern Upper Peninsula of Michigan from 2009–2011. Reproduction did not appear to regulate population growth, as 92 percent of females were pregnant. Annual survival of adult females was 70 percent across years, but poorer annual survival of fawns across years (44 percent) resulted in recruitment being the most influential vital rate to population growth, which increased10 percent from 2009 to 2010, but decreased 13 percent from 2010 to 2011. Variation in population growth emphasized that annual variation in fawn recruitment may have nullified increased growth over time. Most fawn mortalities occurred within 12 weeks of age, emphasizing this period greatly influenced annual survival rates of fawns, and especially population growth. Therefore, I suggest fawns should be considered the priority cohort for deer population management, including mitigation of factors which limit fawn recruitment. Winter severity effects on nutritional condition of adult females primarily influenced survival of adult females and fawns. However, adult female avoidance of interior lowland forests which had greater wolf (Canis lupus) use and commonly aging and over-browsed vegetation ostensibly reduced fawn recruitment through a lack of hiding vegetation and poorer forage. Also, by adult females raising fawns in habitats near roads, the predatory efficacy of coyotes (C. latrans) on adult females and fawns increased. Although predation was the leading cause of deer mortality, bottom-up effects of winter severity on nutritional condition and resource use appeared to be most influential to sustaining a lack of population increase. Hence, I suggest population growth could be improved through habitat management that increases landscape heterogeneity of early successional forests to enhance year-round browse to increase nutritional condition of adult females and hiding cover for fawns.
22

Growth and Urbanization of the Texas Population, 1940-1950

Boulter, Oscar H. 08 1900 (has links)
It is the purpose of this thesis to consider the growth and urbanization of the Texas population since 1880, with primary emphasis on changes which took place during the decade from 1940-1950. The problem involved, therefore, in the second part of this study is to determine the amount of urbanization which took place in Texas during the 1940-1950 decade, to determine the variations among the several regions and "size groups" of cities, and to describe some of the factors related to such increases and variations.
23

ECONOMIC GROWTH AND AGE DEMOGRAPHICS IN DEVELOPED COUNTRIES

Magnusson, Birgir Bjorn 01 May 2023 (has links) (PDF)
This paper presents a time-series model, analyzing the relationship between age structure and economic performance in developed countries, using age demographic growth rates as a measure of changes in age structure, and the growth rate of output per capita for economic growth. The results show the growth rate of output per capita has a positive relationship with the working age demographic, and negative relationships with the young and elderly population growth rates. The dataset used is retrieved from the databases of the OECD and the World Bank and includes 32 countries during the period of 1970-2020. The analysis includes a traditional time-series model, a country fixed effect model, a time-fixed effect model, with results for 1970-2020, and each decade separately. Based on the results, countries that have the highest working age population growth rate have the most economic growth, especially in periods where negative effects of the dependent age demographics are minimized.
24

TELNET CONSTRUCT

LEMASTERS, JENNIFER GRACE 17 July 2003 (has links)
No description available.
25

Ringlavens (Evernia divaricata) population i Dalarna 2020 / Growth rate of Evernia divaricata in Dalarna 2020

Erikers, Katarina January 2022 (has links)
Forests are a key ecosystem to protect biodiversity in Sweden. One important aspect is to protect endangered species and their habitat. Evernia divaricata is an endangered lichen that is sensitive to habitat loss and changing environmental conditions. As consequenceEvernia divaricata is an excellent indicator to observe ecosystem change or habitat disturbance. In the summer 2020 ten different sites were investigated in Dalarna, wherelichens also been investigated two times earlier (year 2006 and 2012) at the same sites. For some of the investigated sites, deforesting was recorded nearby, whereas other sites exhibited favorable conditions without impact because of nearby mires. The Wilcoxon testwas used to examine if there was any statistical difference between the three different inventories, both in terms of number and size of lichens. The study showed that there has been a statistically significant decrease between the three lichen inventories. There was both a decrease over time, but also a decrease within most individual sites. Additional sites should be included, and future inventories will show whether the decline is temporary or if the population keeps decreasing.
26

The urban development in Dubai : A descriptive analysis

Fazal, Fatema January 2008 (has links)
<p> </p><p>The aim of this paper is to analyse the urban development in Dubai by means of the fourquadrant model, presented by DiPasquale and Wheaton, which represents the market for real estate use and assets. The focus is on factors such as economic growth, access to oil, population growth and the incentive of the government to promote developments in Dubai, to study how they affect the real estate market. It is observed how all these factors contribute to the expansion of the construction sector and thereby the stock of space. However, because Dubai's economy is independent of the oil sector, access to oil is solely assumed to contribute to a higher amount of disposable capital and therefore does not have any upward pressure on the rent and the price level as the remaining factors.</p><p> </p>
27

Is there an economic value for elite sports? : The case of Swedish Hockey League

Åström, Erik January 2017 (has links)
The economic value of sport has long been an interesting subject to study. Proponents arguing there is big monetary return for a region hosting a professional sports team. However, majority of studies done on the subject point in the same direction where it seems economic return are negligible. Researchers even argue there is rather an alternative cost where money could be better spent on other social structure such as education and health care. The value of sport creates both direct and indirect effect. In this essay I will look at whether there could be any indirect spillover effects from hosting a hockey team in the highest league. Due to its simplicity, a difference-in-difference (DiD) method will be used on municipalities hosting a hockey team. This when looking at Gross Regional Product (GRP), unemployment rate and population growth to municipalities without a hockey team. The results of this study are ambiguous and hard to interpret when sign on coefficient differ between variables and municipalities. However, there seem to be a correlation between lower unemployment rate and population growth and an increase in GRP when a team is qualifying to SHL. It cannot be determined whether this depend on economic growth or success of their professional sports team.
28

Skipton-in-Craven, 1865 to 1914 : a study of urban growth in a small textile town

Jackson, Kenneth Christopher January 2011 (has links)
The catalyst for the urban growth of Skipton during the formative period of the modern town between 1865 and 1914 was indigenous investment and organisational change in cotton textiles in the aftermath of the Cotton Famine. Railway investment also played an important, although lesser part. The process was facilitated notably by the relaxation of policy on land tenure by the principal landowner and by the work of a well managed local authority. The resulting net in-migration, along with the internal redistribution of population necessitated by the extension of commercial and other services in the town centre, was accommodated by house building in clusters which were either aligned with or removed from the main factory sites. This gave rise to a distinctive pattern of social and spatial segregation, the distribution of which was governed principally by the need for factories to have access to water supplies for steam raising and condensing. Thus the canal corridor beyond the existing built-up area was subject to textile colonisation while wholly residential development was more closely associated with existing high status housing elsewhere. The study considers the processes involved in creating this pattern of development with particular reference to the values and activities of the principal decision-makers. It also discusses the resultant shift in power and influence from the principal landowner to the local authority and to industrial and commercial interests which increasingly were based outside the town. Arising from this a model of urban growth is proposed and tested against neighbouring small textile towns.
29

A evolução da qualidade das águas do rio Paraíba do Sul / The evolution of water quality in the Paraiba do Sul River

Rosa, Denise Mecunhe 03 October 2012 (has links)
A presença de uma série de usos que envolvem o consumo intensivo da água é consequência direta do intenso processo de industrialização e urbanização, bem como do crescimento populacional. As estações de tratamento de esgoto funcionam como uma barreira ambiental aumentando os múltiplos usos das águas de um manancial. Esta melhoria na qualidade reduz as doenças de veiculação hídrica que é abastecida por estas águas. Visando contribuir com a melhor visualização do assunto, propõe-se analisar a evolução da qualidade das águas durante 29 anos no rio Paraíba do Sul, considerando o impacto do crescimento populacional e os efeitos advindos da implantação das ETEs na extensão paulista do rio. Os parâmetros selecionados foram oxigênio dissolvido, demanda bioquímica de oxigênio, demanda química de oxigênio, fósforo e série de nitrogênio, além do índice de qualidade das águas, índice de qualidade das águas para fins de abastecimento público, índice de qualidade das águas para proteção da vida aquática e das comunidades aquáticas e índice de estado trófico, obtidos no Relatório de Qualidade das Águas Interiores do Estado de São Paulo, publicado anualmente pela CETESB. Os resultados obtidos indicam que a redução do aporte de esgoto doméstico sem tratamento nas águas, quando priorizado os trechos onde o impacto atinge maior amplitude associado à morfologia do rio, a recuperação da qualidade das águas, em termos de DBO, DQO é OD, alcança maior extensão. Em termos de nitrogênio e fósforo, é necessário adotar medidas de redução na fonte / There are a number of uses that involve the water consumption that are direct consequences of the industrialization and urbanization intensive process, as well as population growth. The sewage treatment plants serve as environmental barriers increasing the multiple uses of water. This improvement in water quality reduces the risk of spreading diseases to the public that are served by these waters. To contribute with a better view of the subject, it is proposed to analyze the evolution of water quality within 30 years in the flow of the Paraiba do Sul River, considering the impact of population growth and the effects arising from the implementation of sewage treatment plants in the extension of the river. The selected parameters to be analyzed were dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, phosphorus and nitrogen series, besides the water quality index (IQA), the water quality for public supply index (IAP), the water quality for protection of aquatic life and communities index (IVA) and trophic state index (IET), obtained in the Inland Waters Quality of São Paulo State Report, published annually by CETESB. The results indicate that reducing the inflow of untreated sewage waters, when prioritizing the stretches where the impact reaches higher amplitude associated with the morphology of the river, the recovery of water quality in terms of BOD, COD and OD, reaches greater extension. In terms of nutrients, such as nitrogen and phosphorus, it is necessary to adopt measures to reduce them at source
30

The comparative demography of invasive plants

Jelbert, K. January 2018 (has links)
Biodiversity, ecosystems, industry and human health are threatened by invasive plant species. The costs of mitigating damages run into billions of pounds per annum. Fundamental to the control of invasive plant species is an ability to predict which species will become invasive. Yet identification of predictive differences between invasive and non-invasive species has proven difficult to pinpoint. In this thesis I identify several weaknesses within published literature, and using field experiments and meta-analyses we address these to find consistent predictors of invasiveness amongst plants. Specifically, I recognize that predictors of invasiveness can be identified by studying plant species in the native range because species may undergo phenotypic and demographic changes following naturalization (Chapters 2 – 5). I also recognize the importance of comparing globally invasive and non-invasive species, and the importance of accounting for phylogenetic relationships so as not to inflate or conceal differences (Chapters 2 – 4). Finally, I investigate whether particular analyses are more appropriate for investigating life history and demographic differences (Chapter 5). This thesis comprises an introductory chapter (Chapter 1), four data chapters (Chapters 2 - 5) and a general discussion (Chapter 6). Chapters 2 and 3 compare life history traits of plant species known to be invasive elsewhere, with their exported but non-invasive sympatric relatives in the native range. Chapter 4 utilizes Population Projection Matrices held within the COMPADRE Plant Matrix Database, to compare demographic projections of stable and transient dynamics of invasive and non-invasive plants; and Chapter 5 compares ten metrics, derived from Population Projection Matrices, of seven invasive species between the native and invaded range to determine if there are demographic or life history differences that facilitate invasion, and to identify those analyses that are most likely to reveal such differences. I find reproductive capacity to be a predictor of invasiveness, and that analyses of transient dynamics are more likely than analyses of projected stable dynamics to reveal demographic or life history differences between invasive and non-invasive species or populations of plants. I discuss these findings in the context of invasive risk assessment protocols and highlight future research opportunities.

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