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Aspects of the life-cycle energetics of two subspecies of Dunlin Calidris alpinaAl-Mansour, Mansour I. January 2000 (has links)
Dunlin from two breeding populations, C.a.schinzii from Iceland and C.a.alpina from northern Scandinavia, were studied during and after migration through Teesmouth, north-east England, and in captivity. C.a.schinzii winters in north-west Africa and has a much longer migration pathway than C.a.alpina which winters in Britain and around the North Sea. Measurements of Resting metabolic Rate (RMR) were made for the two subspecies of Dunlin in March and November in order to establish the relationship between resting metabolic rate and temperature and hence energy costs of living at different temperatures (20 C - 0 C). Energy costs of living in C.a.alpina were 21% higher than C.a.schinzii. Measurements of Basal Metabolic Rate (BMR) were made for the two subspecies (before, during and after moult) in conjunction with measurements of body compositions using Total Body Electrical Conductivity (TOBEC) in order to estimate the costs of moult. Energy costs of moult were 1692 KJ for alpina and 1016 KJ for schinzii.Energy costs of migration were estimated by measuring the amount of fat laid down before departure by wild Dunlin of the two populations, with the aid of Total Body Electrical Conductivity (TOBEC). Energy costs of migration were estimated as 3489 KJ for alpina, and 5156 KJ for schinzii. Energy costs of egg production and incubation were estimated from other workers’ studies of other (similar) species. Energy costs of egg production were only 220 KJ for the two subspecies whereas the costs of incubation were 1232 KJ and 1143 KJ in alpine and schinzii, respectively. In contrast to the suggestion by Drent and Piersma (1990), I have found that the costs of migration are considerably less than the costs of living. Also the total annual energy cost for those Dunlin wintering in colder areas i.e. C.a.alpina is much higher than for those wintering in tropical regions i.e. C.a.schinzii. Energy costs are not the only factors that affect a bird's lifetime output of young. C.a.alpina uses a different migration strategy to C.a.schinzii but may breed on better breeding grounds, and hence achieve more successful reproduction.
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A geographical analysis of population change in the hill land of western Wisconsin, 1870-1950Polk, Robert R. January 1964 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1964. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (p. 429-436).
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Geography, Housing Prices, and Interregional MigrationBitter, Christopher January 2008 (has links)
This dissertation consists of three papers that explore the intersection between geography and housing markets. The research examines both how geographic context shapes housing prices and how house prices influence geography through household location decisions.The first paper explores the spatial structure of housing prices within Tucson, Arizona. Hedonic house-price studies typically assume that housing attribute prices are constant over space. The research tests this assumption and compares two methods of incorporating spatial-varying parameters into house-price models: geographically weighted regression and the spatial expansion method. The results provide evidence that housing attribute prices do indeed vary with geographic context and suggest that more reliable parameter estimates and better house-price estimation accuracy can be achieved through the use of these techniques.The second paper builds upon the first by examining how more realistic conceptions of housing market spatial structure influence the hedonic price estimates of location-specific externalities. The empirical analysis examines how two key spatial effects, spatial dependence and spatial heterogeneity, impact the marginal price estimates for proximity to the Rillito River, within Tucson, Arizona. Both spatial effects are found to influence the resulting estimates, but spatial heterogeneity is of greater practical importance as the price estimates vary widely with geographic context. This research highlights the importance of considering both spatial effects in hedonic externality valuations.The final paper explores how housing prices influence interregional migration patterns, and more specifically, how their influence varies with both stage in the life course and educational attainment. The research models metropolitan migration within the United States during the period 1995 to 2000. The results indicate that housing prices play an important role in driving regional demographic change, as their influence varies with both demographic characteristics. High housing prices deter individuals in their late twenties and early thirties, but their influence wanes during middle age. House prices become more important as individuals near retirement. The results also provide evidence that college graduates respond more to house price differentials than do persons with lower levels of educational attainment.
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Modeling Seed Dispersal and Population Migration Given a Distribution of Seed Handling Times and Variable Dispersal Motility: Case Study for Pinyon and Juniper in UtahNeupane, Ram C. 01 May 2015 (has links)
The spread of fruiting tree species is strongly determined by the behavior and range of fruit-eating animals, particularly birds. Birds either consume and digest seeds or carry and cache them at some distance from the source tree. These carried and settled seeds provide some form of distribution which generates tree spread to the new location. Firstly, we modal seed dispersal by birds and introduce it in a dispersal model to estimate seed distribution. Using this distribution, we create a population model to estimate the speed at which juniper and pinyon forest boundaries move.
Secondly, we introduce a fact that bird movement occurs based on local habitat type to receive modified dispersal model. Birds can easily move many kilometers but habitat changes on the scale of tens of meters with rapidly varying. We develop a new technique to solve the modified dispersal model and approximate the form of transported seed distributions in highly variable landscapes. Using a tree population model, we investigate the rate of forest migration in variable landscapes. We show that speeds calculated using average motility of animals and mean seed handling times accurately predict the migration rate of trees.
Regional scale forest distribution models are frequently used to project tree migration based on climate and geographic variables such as elevation, and regional presence-absence data. It is difficult to accurately use dispersal models based on large-scale presence-absence data, particularly for tree species dispersed by birds. The challenge is that variables associated with seed dispersal by birds are represented only few meters while the smallest pixel size for the distribution models begins with few kilometers. Transported seed distribution estimated in the variable landscape offers a tool to make use of this scale separation. Finally, we develop a scenarios that allows us to find large scale dispersal probabilities based on small scale environmental variables.
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Migrace a uprchlictví v současném globalizovaném světě s ohledem na sociální aspekty / Migration and refugees in today's globalized world with regard to the social aspectsSufčák, David January 2019 (has links)
The thesis focuses on "Migration and refugees in the current globalized world with regard to social aspects" and its key objective is to map attitudes of the population in the Czech Republic to refugees and migrants in the shadow of the European migration crisis. The thesis consists of two parts: theoretical and empirical. The theoretical part contains a detailed presentation of the refugeeism and migration phenomena. It provides basic definitions of the terms "migration", "migrant" and "refugee". Further, it also describes the history and present of migration and refugees and provides prediction of the future. A deep analysis is provided of the current European migration and refugee crisis and its social, political, legislative, economic and security aspects. The thesis also focuses on causes of migration, its impacts, cultural conflicts and potential solutions. The theoretical part also contains an analysis of social work with migrants and refugees in the Czech Republic. The thesis also addresses the role of media and disinformation (the so-called fake news) on the Internet. The theoretical part also presents different approaches of individual countries to migration and refugees across the continents. The second part of the thesis is empirical and it uses the strategy of quantitative research;...
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Vliv migrace na vybrané socioekonomické ukazatele / Impact of migration on the selected socio-economic indicatorsVrána, Martin January 2011 (has links)
This thesis deals with the topic of migration. In the theoretical level the work defines the term migration, further it discusses its reasons, forms, types and consequences. In the practical level the work examines the impact of migration on the socio-economic indicators. It is focused to characteristics of the migration impacts on social and economic indicators of the Czech Republic. The aim of the work is to assess the situation, which could arise in the future as a direct consequence of migration. The work further also brings information about the current situation and migration development in the Czech Republic, it also informs what kind of migration policy was chosen by the Czech Government and discusses the topic of national minorities living in our country. Selected goal of the work is processed in a third part, which discuss economic, social and demographic aspect of migration.
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Pastarieji Lietuvos gyventojų migracijos pokyčiai ir grįžtamoji migracija / Recent migration changes and return migration in LithuaniaVaškelienė, Irena 20 January 2009 (has links)
Magistro baigiamojo darbo tema yra aktuali tiriant Lietuvos gyventojų migracijos procesus. Lietuvos gyventojų migracijos srautai, mastai bei problemos turi įtakos ne tik sociodemografiniams gyventojų pokyčiams, tačiau ir valstybės vykdomai ekonominei, socialinei ir kitų sričių politikai. Grįžtamosios migracijos tema yra nauja, kadangi iki šiol nebuvo atlikti tyrimai, nustatantys grįžtamosios migracijos priežastis bei grįžusiųjų migrantų integracijos problemas. Grįžtamosios migracijos veiksnių ir problemų identifikavimas yra svarbus, siekiant sukurti ir įgyvendinti priemones, skatinančias Lietuvos gyventojų grįžtamąją migraciją. Tad baigiamojo darbo objektas yra pastarosios Lietuvos gyventojų migracijos tendencijos bei grįžtamoji migracija. Baigiamojo darbo objektas nagrinėjamas, siekiant įvertinti Lietuvos gyventojų migracijos srautus, apimtį, priežastis, nustatyti grįžtamąją migraciją skatinančius veiksnius, grįžusių migrantų integracijos problemas, o taip pat siekiant pateikti pasiūlymų grįžtamosios migracijos problemoms spręsti. Įgyvendinant baigiamojo darbo uždavinius buvo atlikta migracijos teorijų, Lietuvos migracijos istorijos bei grįžtamosios migracijos mokslinės literatūros bei grįžtamosios migracijos tyrimų analizė, teisinės ir statistinės literatūros analizė, nustatyti ir įvertinti grįžtamosios migracijos veiksniai, problemos bei numatytos priemonės, skatinančios grįžtamąją migraciją.
Baigiamajame darbe buvo iškeltos hipotezės: intensyvūs migracijos srautai sudaro... [toliau žr. visą tekstą] / The subject of the master work is urgent reseach of the migration processes of Lithuania population. The streams, scales, and problems of Lithuania population migration have influence not only on sociodemographical changes of population but also on the economic, social and other policies of the government. Return migration is a new subject, as until recent the reseach on return migration reasons and the problems of migrants integration has not been done. The identification of its factors and problems is important. It is essencial in creating measures and putting them into practice, because it stimulates return migration of Lithuania population. The object of the study is the recent return migration of Lithuania population and its tendencies. The object is investigated trying to evaluate the streams, scales and reasons of Lithuania migration and the problems of return migrants integration. Moreover, the study presents some suggestions how to solve the problems of return migration. Fulfilling the assigments of the work some analysis on migration theories, Lithuania migration history, scientific as well as juridical and statistical literature, return migration reseach have been done. The factors and problems of return migration are determined and evaluated here. Also, the measures stimulating return migration are provided in the study.
The hypotheses made in the work are that intensive migration streams allow the factor of return migration to form and social and family relations... [to full text]
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Динамическое моделирование и прогнозирование динамики научной миграции : магистерская диссертация / Dynamic modeling and forecasting of the dynamics of scientific migrationВоробьева, А. В., Vorobyeva, A. V. January 2021 (has links)
Данная работа посвящена разработке алгоритма для построения динамической модели потоков научной миграции. В работе изучаются теоретические аспекты миграции населения, производится сбор и анализ статистических данных Росстата и зарубежных источников. Также проводится обзор теоретико-методологических подходов к моделированию научной миграции, далее для создания модели определяются необходимые предположения, ограничения и параметры. Была составлена математическая формула для расчета и создан алгоритм с помощью пакета программ Matlab. Результаты работы алгоритма были проанализированы. / This work is devoted to the development of an algorithm for constructing a dynamic model of scientific migration flows. The paper studies the theoretical aspects of population migration, collects and analyzes statistical data from Rosstat and foreign sources. Also, a review of theoretical and methodological approaches to modeling scientific migration is carried out, then the necessary assumptions, limitations and parameters are determined to create a model. A mathematical formula for the calculation was drawn up and an algorithm was created using the Matlab software package. The results of the algorithm were analyzed.
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Socio-economic history of North Shawa, Ethiopia (1880s-1935)Demisie, Dechasa Abebe 01 1900 (has links)
This thesis attempts to address how and why North Shäwa deteriorated from a political heartland to a region of impoverished peasants by the beginning of the 20th century. One of the factors that determine the selection of the place for a seat of the government for a region or country and sustainability of its system is its resource potential. In this case, arable and grazing land with other related land resources were decisive. They were some of the major factors contributing to both the origin and development of the kingdom. However, by the beginning of the 20th century, the region was abandoned by the court and by a significant proportion of its population. This was mainly because of the impoverishment of the region. The growth of the number of consumers (town dwellers) and the supplies needed by the kingdom exceeded the carrying capacity of North Shäwa. The economic productivity of the region could not correspond to the development of its needs. Thus, this thesis accords due emphasis to the factors that contributed to the impoverishment of North Shäwa and the consequences that followed. Throughout the thesis, North Shäwan peasants are the main subject of discussion. Political, social, cultural and geographical factors that impacted on the peasants’ economy and that retarded its development are discussed in the study. It also attempts to unearth the measures taken by the court and peoples of North Shäwa to withstand or escape from the prevailing socio-economic problems. Finally a comparison is made with other regions of the country to describe the political and socio-economic status of North Shäwans that continue to live in the region. This discussion covers the period from the 1880s up to the Italian occupation of Ethiopia in 1935 / History / D.Litt. et Phil. (History)
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海平面上升對土地利用變遷與人口遷移影響之研究─以台北都會區為例 / The influence of sea level rise on land use changes and population migration ─ A study of Taipei metropolitan area張伊芳, Chang, Yi Fang Unknown Date (has links)
IPCC於第四次報告書中,模擬氣候持續暖化預測未來海平面上升之情形,而海平面上升對於人口集中的台北都會區將產生莫大之衝擊,同時亦會造成土地利用變遷。本研究目的在於探討海平面上升對台北都會區土地利用變遷之影響,以及受淹沒地區之人口未來可能之遷移區位,主要係從社會經濟發展層面進行分析。運用二元羅吉斯迴歸模式並結合土地利用轉換與影響模型(CLUE-s),以四種不同情境模擬土地利用變遷之情況,其情境分別為海平面上升59公分管制農林地與不管制,以及海平面上升100公分管制農林地與不管制。
研究結果顯示,海平面上升之情形越嚴重,未來的都市建地發展會越趨向擴張的形式,對農林地產生變遷之壓力;而於同一海平面上升水平下,針對農林地進行管制,其建地之發展會較為集中於都市計畫地區範圍內,且多數人口亦將遷移至此,容易形成人口壓力。此外,土地利用變遷模擬所得之新增建地部分,於情境A、C下足以容納受影響之人口,但情境B、D則不足以容納,皆會對台北都會區產生容受力之問題,產生累計人口超過計畫人口之現象。因此,建議未來政府於都市發展上,可調整都市計畫內之土地使用強度或都市範圍,也可利用都市更新之方式減少新的土地開發;此外,從國家層級分析,未來的國土計畫法於立法上,亦可將更多氣候變遷相關影響因子納入四大功能分區,透過適宜性分析進行分類分級,以做為未來土地利用發展之引導。 / The 4th IPCC report simulated climate warming and predicted future sea-level rise scenarios. A sea level rise will have a great impact on the population of the Taipei metropolitan area, and it will also produce land-use changes. The purpose of this study is to research the impact of sea level change on land use changes and population migration in Taipei metropolitan, and the areas that will be immigrated by the flooded areas. The method used includes binary logistic regression model combined with Conversion of Land Use and its Effects Model (CLUE-s). Setting the sea-level rise and regulating agricultural land, forest land of the four simulated situations.
The results show that the higher sea level rises, the more transformation towards urban development in the future, and the higher sea level will also pressure agriculture and forestry changes. As a result of population pressure on Taipei metropolitan area, the same level of sea-level rise for the regulation of agriculture and forestry land, the development of building sites and population migration will be more concentrated on urban planning areas. In addition, the simulation of land use change generated new building sites, sufficient enough to accommodate the affected population under A and C simulated situations, but B and D couldn’t generate such results. Instead, it will generate a carrying capacity issue.
Therefore, this thesis suggests that the government adjust the intensity of land use in urban development, urban areas and urban renewal of urban planning. In addition, the analysis from the national level, the future legislation of Land Planning Act should include the relation of climate change impact factors as a consideration of future land use development.
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