Home About us Contact
|
Home About us Contact | ||
|
|
||
Population Change (population + change)
Selected AbstractsRural Demographics Racial/Ethnic Diversification in Metropolitan and Nonmetropolitan Population Change in the United States: Implications for Health Care Provision in Rural AmericaTHE JOURNAL OF RURAL HEALTH, Issue 4 2003Steve H. Murdock PhD Because of a variety of historical, discriminatory, and other factors, minority populations have had lower levels of access to health care in rural as well as urban areas and higher rates of both mortality and morbidity than nonminority populations. Although minority health issues have often been seen as primarily urban issues, this article demonstrates that minority population growth has become a major component of total population growth in rural areas in the past several decades (accounting for nearly 62% of the net growth in the nonmetropolitan population of the United States in the 1980s and for nearly 42% in the 1990s), that future US population growth is likely to be largely a product of minority population growth (nearly 89% of US net population growth from 2000 to 2100 is projected to be due to minority population growth), and that the incidence of diseases and disorders in the US population will come to increasingly involve minority populations (by 2050 roughly 43% of all disease/disorder incidences would involve minority population members). The growth of younger minority populations with disproportionately impoverished socioeconomic characteristics will pose challenges for rural areas and health care systems, which also are likely to face health issues created by disproportionately older populations [source] Population change due to geographic mobility in Albania, 1989,2001, and the repercussions of internal migration for the enlargement of TiranaPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 6 2007Michalis Agorastakis Abstract Being a country in transition, Albania has sustained vast political and socio-economic changes over the past 15 years, mostly due to its engagement in democratisation and transformation to an open market economy. The pathway to transition has involved economic hardship and political unrest and has been accompanied by intense, large-scale, geographical mobility. This paper describes population change due to internal and international migration, 1989,2001, using Census data at district level. Its contribution is a technical one in applying a method that allows new estimates to be made of the scale of internal migration in Albania. Descriptive analysis of population changes in 36 Albanian districts, based on the last two censuses, lead to the identification of poles of attraction of internal migrants. Limited data concerning the 1989 Census and the 12 years between the censuses resulted in the creation of various indices that characterise internal migration, such as the Attraction and Expulsion Index stemming from the Origin,Destination Matrix of the districts. In addition an Index of Conservation of the population and an Index of External Migration were also derived at the district level. By considering internal and international migration as two separate phenomena, we emphasise their uniqueness in affecting population change in Albania. The District of Tirana, capital of Albania, absorbed the majority of the inflow of internal migrants. The latter part of the paper focuses on the population of Tirana as the county's major migration destination. Copyright © 2007 John Wiley & Sons, Ltd. [source] Origins and characteristics of Nearctic landbirds in Britain and Ireland in autumn: a statistical analysisIBIS, Issue 4 2006IAN A. MCLAREN We used data from eastern North America in regressions to explain autumn frequencies of Nearctic landbird species in Britain and Ireland (UK-IR). The data were: day-counts of 16 August,15 November from Nova Scotia (NS) on Sable Island 1963,2000 and Seal Island (1963,2002), combined in half-monthly intervals to account for seasonality; published seasonal totals (10- to 11-day intervals, 20 August,10 November 1955,80) of birds killed at a Florida (FL) TV tower; and published counts following a ,Fallout', 11 October 1998, of unseasonal species and southern vagrants in NS, believed to have originated as migrants in the southeast USA that followed a cold front offshore into strong southwest flow beyond. We also used the following species variables: body mass and wing length for size; sd of mass as a proxy for lipid capacity; a five-level index of migratory span (1 for within North America to 5 for almost totally to South America); latitude of easternmost breeding, and distance to nearest normal range to indicate status in NS; a two-level index for day vs. night migrants; an index, where pertinent, of significant population change (0 and 2 for a decrease and increase, respectively, 1 for no change). We also used classification and regression trees to cluster the potential transatlantic vagrants into homogeneous groups based on the explanatory variables. Standard generalized linear model regressions using counts from NS islands and FL produced highly positively skewed residuals (many species too common in UK-IR), but robust regressions eliminated statistical problems, and strengthened effects of non-count variables. Results using Fallout records, representing a subset of longer-distance night migrants, were statistically acceptable. The Fallout list, when supplied with counts from the same species from the NS islands and FL, produced highly significant (R2 = 0.79,0.93) and statistically acceptable regressions that were not improved by robust versions. Overall, the results indicate that October counts, especially of generally larger, longer-distance migrants, best represented those reaching UK-IR. The effect of geographical remoteness was negative , vagrants in NS were less likely to appear in UK-IR. Population changes were important in predicting the 1956,2003 UK-IR counts from 1955,80 FL counts. The seasonal characteristics, high explanatory power of the Fallout list and over-representation of probable over-ocean migrants in the standard regressions all support suggestions by others that many Nearctic vagrants in UK-IR originate in flights off southeast USA and are displaced downwind across the North Atlantic. [source] Population changes in Phytophthora infestans in Taiwan associated with the appearance of resistance to metalaxyl,PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 9 2002Kenneth L Deahl Abstract In recent years, late blight, caused by Phytophthora infestans (Mont) De Bary, has increased in severity in many parts of the world, and this has been associated with migrations which have introduced new, arguably more aggressive, populations of the pathogen. In Taiwan, late blight has been endemic on outdoor tomato crops grown in the highlands since the early 1900s, but recent epidemics have been more damaging. To ascertain the present status of the Taiwanese population of P infestans, 139 isolates of the pathogen collected and maintained by the Asian Vegetable Research and Development Center (AVRDC) were characterized using mating type, metalaxyl sensitivity, allozyme genotype, mitochondrial haplotype and RFLP fingerprinting. Up to 1997, all isolates were found to belong to the old clonal lineage of P infestans (US-1 and variants), but in isolates from 1998 a new genotype appeared, and by 2000 this had apparently completely displaced the old population. This new genotype was an A1 mating type and has the dilocus allozyme genotype 100/100/111, 100/100 for the loci coding for glucose-6-phosphate isomerase and peptidase, respectively. These characters, together with RG57 fingerprinting, indicated that these isolates belonged to the US-11 clonal lineage, a minority (11%) being a previously unreported variant of US-11. Whereas metalaxyl-resistant isolates were not detected in the old population, 96% of the new genotypes proved resistant, with the remainder being intermediate in sensitivity. It may be inferred from this sudden, marked change in the characteristics of the Taiwanese P infestans that a new population of the pathogen was introduced around 1997,98 and that this may well have already been metalaxyl-resistant when it arrived, although a role for in situ selection cannot be excluded. © 2002 Society of Chemical Industry [source] Range-wide patterns of greater sage-grouse persistenceDIVERSITY AND DISTRIBUTIONS, Issue 6 2008Cameron L. Aldridge ABSTRACT Aim, Greater sage-grouse (Centrocercus urophasianus), a shrub-steppe obligate species of western North America, currently occupies only half its historical range. Here we examine how broad-scale, long-term trends in landscape condition have affected range contraction. Location, Sagebrush biome of the western USA. Methods, Logistic regression was used to assess persistence and extirpation of greater sage-grouse range based on landscape conditions measured by human population (density and population change), vegetation (percentage of sagebrush habitat), roads (density of and distance to roads), agriculture (cropland, farmland and cattle density), climate (number of severe and extreme droughts) and range periphery. Model predictions were used to identify areas where future extirpations can be expected, while also explaining possible causes of past extirpations. Results, Greater sage-grouse persistence and extirpation were significantly related to sagebrush habitat, cultivated cropland, human population density in 1950, prevalence of severe droughts and historical range periphery. Extirpation of sage-grouse was most likely in areas having at least four persons per square kilometre in 1950, 25% cultivated cropland in 2002 or the presence of three or more severe droughts per decade. In contrast, persistence of sage-grouse was expected when at least 30 km from historical range edge and in habitats containing at least 25% sagebrush cover within 30 km. Extirpation was most often explained (35%) by the combined effects of peripherality (within 30 km of range edge) and lack of sagebrush cover (less than 25% within 30 km). Based on patterns of prior extirpation and model predictions, we predict that 29% of remaining range may be at risk. Main Conclusions, Spatial patterns in greater sage-grouse range contraction can be explained by widely available landscape variables that describe patterns of remaining sagebrush habitat and loss due to cultivation, climatic trends, human population growth and peripherality of populations. However, future range loss may relate less to historical mechanisms and more to recent changes in land use and habitat condition, including energy developments and invasions by non-native species such as cheatgrass (Bromus tectorum) and West Nile virus. In conjunction with local measures of population performance, landscape-scale predictions of future range loss may be useful for prioritizing management and protection. Our results suggest that initial conservation efforts should focus on maintaining large expanses of sagebrush habitat, enhancing quality of existing habitats, and increasing habitat connectivity. [source] Long-term dynamics of pelagic fish density and vendace (Coregonus albula (L.)) stocks in four zones of a lake differing in trawling intensityECOLOGY OF FRESHWATER FISH, Issue 2 2001T. J. Marjomäki Abstract , An 11-year time series of hydroacoustic fish density estimates and fisheries statistics of vendace (Coregonus albula (L.)) from four zones of a lake differing in trawling intensity was analyzed in order to test the hypothesis that intensive trawling has detrimental effects on pelagic fish stocks, especially vendace recruitment. The standardized fish density estimate in trawled zones showed no decrease in comparison to the non-trawled zone. No signs of recruitment failure associable with trawling intensity were found. The growth of vendace at the end of the study period was slower than that at the beginning, indicating a higher density, most clearly so in the zone with highest trawling intensity. No significant correlations were detected between 3-year mean trawling intensity and yield per unit effort of over-1-year-old vendace or fish density in any zone. Thus, no evidence to support the hypothesis was found. This was suggested to be due to density-dependent compensatory processes in recruitment and/or natural mortality effectively counteracting the population change induced by exploitation., [source] Extracting long-term patterns of population changes from sporadic counts of migrant birdsENVIRONMETRICS, Issue 5 2010Joanna Mills Flemming Abstract Declines of many North American birds are of conservation concern. For almost 40 years, experienced birders have kept daily counts of migrant landbirds during visits to Seal and Brier Islands, both of which are off Nova Scotia's southern tip. Here we assess the utility of Generalized Additive Models (GAMs) to extract patterns of population change of a common migrant to Seal Island, the Ruby-crowned Kinglet, while controlling for other influences including season, weather and effort. We also demonstrate, using counts of the Kinglet from Brier Island as well as counts of another common migrant, the Yellow-rumped Warbler, how our GAM methods can combine data from different geographic areas or distinct species. Most existing analyses of similar long-term data sets have used linear models to estimate trends. Our results and comparisons suggest that GAMs are a powerful way of extracting more information from such data. Copyright © 2009 John Wiley & Sons, Ltd. [source] Gendering the Black Death: Women in Later Medieval EnglandGENDER & HISTORY, Issue 3 2000S. H. Rigby This review article of Mavis Mate's Daughters, Wives and Widows after the Black Death: Women in Sussex, 1350,1535 (1998) locates Mate's work within the broader context of the debate about changes in women's social position caused by the collapse in population following the Black Death. Was demographic decline accompanied by growing social and economic opportunities for women or should historians emphasise the continuity of female work as low-skilled, low-status and low-paid throughout the late medieval and early modern periods? How did women's role in the labour market affect the age of marriage, fertility rates and long-term population change? In general, Mate's conclusions offer support to the ,pessimists': women's work was vital to the household but economic centrality did not bring a commensurate social power or legal rights and the ideology of female subordination remained firmly in place. The main problem with Mate's case is, inevitably, a lack of evidence, for family structure, for the sexual division of labour and, above all, for affective relations. Nevertheless, this detailed, empirically based local study shows how successfully women's history has moved into the historical mainstream. [source] SUBURBANIZATION IN COUNTRIES IN TRANSITION: DESTINATIONS OF SUBURBANIZERS IN THE TALLINN METROPOLITAN AREAGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 2 2007Kadri Leetmaa ABSTRACT. Suburbanization is one of the key phenomena of spatial population change in many countries in transition. Yet we know surprisingly little about the population carrying out the post-socialist suburbanization process. The objective of this article is to improve on this situation by studying the Tallinn metropolis in Estonia. Our analysis, which covers the inter-censal period 1989 to 2000, focuses on the differences between population subgroups with respect to their probabilities to move to the suburbs. As such, it also clarifies choices of destination by dwelling and municipality type. For the analysis, we use individual anonymous 2000 census data and logistic regression. The results indicate that suburbanization was a socially polarizing process during this period. People with low social status had the highest probability to sub-urbanize, and mainly occupied the pre-existing housing stock. Conversely, people with high social status were less likely to move into suburban areas, yet when they did they moved to the most attractive destinations in the suburbs (new single-family houses, coastal municipalities and municipalities closer to the city). [source] Origins and characteristics of Nearctic landbirds in Britain and Ireland in autumn: a statistical analysisIBIS, Issue 4 2006IAN A. MCLAREN We used data from eastern North America in regressions to explain autumn frequencies of Nearctic landbird species in Britain and Ireland (UK-IR). The data were: day-counts of 16 August,15 November from Nova Scotia (NS) on Sable Island 1963,2000 and Seal Island (1963,2002), combined in half-monthly intervals to account for seasonality; published seasonal totals (10- to 11-day intervals, 20 August,10 November 1955,80) of birds killed at a Florida (FL) TV tower; and published counts following a ,Fallout', 11 October 1998, of unseasonal species and southern vagrants in NS, believed to have originated as migrants in the southeast USA that followed a cold front offshore into strong southwest flow beyond. We also used the following species variables: body mass and wing length for size; sd of mass as a proxy for lipid capacity; a five-level index of migratory span (1 for within North America to 5 for almost totally to South America); latitude of easternmost breeding, and distance to nearest normal range to indicate status in NS; a two-level index for day vs. night migrants; an index, where pertinent, of significant population change (0 and 2 for a decrease and increase, respectively, 1 for no change). We also used classification and regression trees to cluster the potential transatlantic vagrants into homogeneous groups based on the explanatory variables. Standard generalized linear model regressions using counts from NS islands and FL produced highly positively skewed residuals (many species too common in UK-IR), but robust regressions eliminated statistical problems, and strengthened effects of non-count variables. Results using Fallout records, representing a subset of longer-distance night migrants, were statistically acceptable. The Fallout list, when supplied with counts from the same species from the NS islands and FL, produced highly significant (R2 = 0.79,0.93) and statistically acceptable regressions that were not improved by robust versions. Overall, the results indicate that October counts, especially of generally larger, longer-distance migrants, best represented those reaching UK-IR. The effect of geographical remoteness was negative , vagrants in NS were less likely to appear in UK-IR. Population changes were important in predicting the 1956,2003 UK-IR counts from 1955,80 FL counts. The seasonal characteristics, high explanatory power of the Fallout list and over-representation of probable over-ocean migrants in the standard regressions all support suggestions by others that many Nearctic vagrants in UK-IR originate in flights off southeast USA and are displaced downwind across the North Atlantic. [source] Local annual survival of booming male Great Bittern Botaurus stellaris in Britain, in the period 1990,1999IBIS, Issue 1 2002Gillian Gilbert Male Great Bitterns Botaurus stellaris have individually distinctive boom vocalizations which have been used since 1990 to count the British population accurately. We used vocal individuality to identify birds between years and analyse the survival of the British booming population. We used six instances of Great Bitterns known to be the same birds (from radio tracking and re-sighting of darvic rings) in successive years to provide a means of identification independent from vocalizations. All of these birds remained in the same territory from one year to the next. Seven spectrogram measures were chosen as quantitative descriptors of Great Bittern booms. Boom similarity was expressed in terms of Euclidean ,acoustic' distance between descriptors of pairs of birds. Great Bitterns that were known to be the same birds had more similar booms across years than those known to be different. The acoustic distances and knowledge of site fidelity were used to construct parsimonious rules on which to base re-identification decisions and to build survival histories. Great Bittern local survival in Britain as a whole was estimated as 70% (± 5.1 se) with survival in north-west England (at Leighton Moss) higher (82.8%, ± 7.3 se) than that in East Anglian sites (65.2%, ± 5.4 se) (,12 = 3.4, P = 0.07). Movements of males between years were apparent between sites within the Suffolk and Norfolk coastal regions but not on a large scale. Survival of adult males in East Anglia was positively related to winter rainfall, but there was no significant relationship with winter temperature. There was a positive relationship between the annual population change in East Anglia and the annual local adult survival rate. [source] Immigrant Gateways and Hispanic Migration to New Destinations,INTERNATIONAL MIGRATION REVIEW, Issue 3 2009Daniel T. Lichter Our understanding of the underlying demographic components of population change in new Hispanic destinations is limited. In this paper, we (1) compare Hispanic migration patterns in traditional settlement areas with new growth in emerging Hispanic destinations; (2) examine the role of immigration vis-à-vis domestic migration in spurring Hispanic population redistribution; and (3) document patterns of migrant selectivity, distinguishing between in-migrants and non-migrant Hispanics at both the origin and destination. We use several recent datasets, including the 1990 and 2000 Public Use Microdata Samples (which include new regional geocodes), and the 2005 and 2006 files of the American Community Survey. Our results document the widespread dispersion of the Hispanic population over the 1990,2006 period from established Hispanic gateways into new Hispanic areas and other parts of the country. Nearly one-half of Hispanic net migration in new destinations comes from domestic gains. In contrast, both established and other Hispanic areas depend entirely on immigration, with each losing domestic migrants to high growth areas. Migrant flows also are highly differentiated by education, citizenship, and nativity. To fully understand the spatial diffusion of Hispanics requires a new appreciation of the complex interplay among immigration, internal domestic migration, and fertility. [source] Census error and the detection of density dependenceJOURNAL OF ANIMAL ECOLOGY, Issue 4 2006ROBERT P. FRECKLETON Summary 1Studies aiming to identify the prevalence and nature of density dependence in ecological populations have often used statistical analysis of ecological time-series of population counts. Such time-series are also being used increasingly to parameterize models that may be used in population management. 2If time-series contain measurement errors, tests that rely on detecting a negative relationship between log population change and population size are biased and prone to spuriously detecting density dependence (Type I error). This is because the measurement error in density for a given year appears in the corresponding change in population density, with equal magnitude but opposite sign. 3This effect introduces bias that may invalidate comparisons of ecological data with density-independent time-series. Unless census error can be accounted for, time-series may appear to show strongly density-dependent dynamics, even though the density-dependent signal may in reality be weak or absent. 4We distinguish two forms of census error, both of which have serious consequences for detecting density dependence. 5First, estimates of population density are based rarely on exact counts, but on samples. Hence there exists sampling error, with the level of error depending on the method employed and the number of replicates on which the population estimate is based. 6Secondly, the group of organisms measured is often not a truly self-contained population, but part of a wider ecological population, defined in terms of location or behaviour. Consequently, the subpopulation studied may effectively be a sample of the population and spurious density dependence may be detected in the dynamics of a single subpopulation. In this case, density dependence is detected erroneously, even if numbers within the subpopulation are censused without sampling error. 7In order to illustrate how process variation and measurement error may be distinguished we review data sets (counts of numbers of birds by single observers) for which both census error and long-term variance in population density can be estimated. 8Tests for density dependence need to obviate the problem that measured population sizes are typically estimates rather than exact counts. It is possible that in some cases it may be possible to test for density dependence in the presence of unknown levels of census error, for example by uncovering nonlinearities in the density response. However, it seems likely that these may lack power compared with analyses that are able to explicitly include census error and we review some recently developed methods. [source] Modelling long-term pan-European population change from 1870 to 2000 by using geographical information systemsJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES A (STATISTICS IN SOCIETY), Issue 1 2010Ian N. Gregory Summary., The paper presents work that creates a geographical information system database of European census data from 1870 to 2000. The database is integrated over space and time. Spatially it consists of regional level data for most of Europe; temporally it covers every decade from 1870 to 2000. Crucially the data have been interpolated onto the administrative units that were available in 2000, thus allowing contemporary population patterns to be understood in the light of the changes that have occurred since the late 19th century. The effect of interpolation error on the resulting estimates is explored. This database will provide a framework for much future analysis on long-term Europewide demographic processes over space and time. [source] Interspecific differences in foraging preferences, breeding performance and demography in herring (Larus argentatus) and lesser black-backed gulls (Larus fuscus) at a mixed colonyJOURNAL OF ZOOLOGY, Issue 4 2006S.-Y. Kim Abstract Herring gulls Larus argentatus and lesser black-backed gulls Larus fuscus breeding at Walney Island, Cumbria, the largest breeding colony of the two species in the UK, have recently shown very different population trends. The former has declined sharply, whereas numbers of the latter have been maintained for several years. Here we compare aspects of the feeding and breeding ecology of the two species in order to examine whether or not this suggests explanations for their different population trends. Comparison of the ratio of the two species in flight lines leading to different feeding sites and their diet composition showed that the lesser black-backed gulls fed more at sea and the herring gulls fed more in the intertidal zone. Urban resources were used by both these species. These differences have been consistent over the last three decades. Susceptibility to death from botulism at the breeding colony was the same for the two species. The availability of the intertidal zone for foraging appears to have declined in recent years, and this may have had a more negative impact on the herring gull. However, the breeding success of the two species remains relatively high. This study suggests that differences in foraging behaviour and food availability during the breeding season are unlikely to be responsible for the marked differences in demographic trends in the two species. Changes in local food availability during the winter would be expected to have more effect on the resident herring gull. This work highlights the need for more detailed studies of the ecology of both species during the breeding season and in winter in regions showing differing patterns of population change. [source] On the Tasks of a Population Commission: A 1971 Statement by Donald RumsfeldPOPULATION AND DEVELOPMENT REVIEW, Issue 3 2003Article first published online: 20 APR 200 In its most familiar form, analytic assessment of the impact of demographic change on human affairs is the product of a decentralized cottage industry: individual scholars collecting information, thinking about its meaning, testing hypotheses, and publishing their findings. Guidance through the power of the purse and through institutional design that creates and sustains cooperating groups of researchers can impose some order and coherence on such spontaneous activity. But the sum total of the result may lack balance and leave important aspects of relevant issues inadequately explored. Even when research findings are picked up by the media and reach a broader public, the haphazardness of that process helps further to explain why the salience of population change to human welfare and its importance in public policymaking are poorly understood. The syndrome is not unique to the field of population, but the typically long time-lags with which aggregate population change affects economic and social phenomena make it particularly difficult for the topic to claim public attention. A time-tested, if less than fool-proof remedy is the periodic effort to orchestrate a systematic and thorough examination of the causes, consequences, and policy implications of demographic processes. Because the most potent frame for policymaking is the state, the logical primary locus for such stocktaking is at the country level. The Commission on Population Growth and the American Future was a uniquely ambitious enterprise of this sort. The Commission was established by the US Congress in 1970 as a result of a presidential initiative. Along with the work of two earlier British Royal Commissions on population, this US effort, mutatis mutandis, can serve as a model for in-depth examinations conducted at the national level anywhere. Chaired by John D. Rockefeller 3rd, the Commission submitted its final report to President Richard M. Nixon in March 1972. The background studies to the report were published in seven hefty volumes; an index to these volumes was published in 1975. Reproduced below is a statement to the Commission delivered on April 14, 1971 by Donald Rumsfeld, then Counsellor to President Nixon and in charge of the Office of Economic Opportunity. (Currently, Mr. Rumsfeld serves as US Secretary of Defense.) The brief statement articulates with great clarity the objectives of the Commission and the considerations that prompted them. The text originally appeared in Vol. 7 (pp. 1-3) of the Commission's background reports, which contains the statements at public hearings conducted by the Commission. National efforts toward comprehensive scientific reviews of population issues have their analogs at the international level. Especially notable on that score were the preparatory studies presented at the 1954 Rome and 1965 Belgrade world population conferences. The world population conferences that took place in Bucharest in 1974, in Mexico City in 1984, and in Cairo in 1994 were intergovernmental and political rather than scientific and technical meetings, but they also generated a fair amount of prior research. The year 2004 will break the decadal sequence of large-scale international meetings on population, and apart from the quadrennial congresses of the IUSSP, which showcase the voluntary research offerings of its members, none is being planned for the coming years. A partial substitute will be meetings organized by the UN's regional economic and social commissions. The first of these took place in 2002 for the Asia-Pacific region; the meetings for the other regions will be held in 2003-04. The analytic and technical contribution of these meetings, however, is expected to be at best modest. National efforts of the type carried out 30 years ago by the Commission on Population Growth and the American Future would be all the more salutary. [source] Dynamics of ethnic residential segregation in Göteborg, Sweden, 1995,2000POPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 2 2008Åsa Bråmå Abstract Most explanatory frameworks within segregation research interpret patterns of ethnic residential segregation as the result of how members of different ethnic groups have moved (or not moved) within the city and to the city from the surrounding world. Yet, few attempts have been made to proceed beyond relatively static accounts based on descriptions and analysis of patterns of segregation, to address more directly the dynamics behind the patterns. In this article, a longitudinal, individual-based data-set is used in order to analyse the dynamics, in terms of migration and natural population change, that have reproduced and transformed patterns of segregation in Göteborg (Gothenburg), Sweden, between 1995 and 2000. The analysis deals with questions concerning changes in the degree of concentration and dispersal of different minority groups, and the role of the minority enclaves as ports of entry to the local housing market for different groups. The findings have relevance for wider theoretical issues related to the interpretation and explanation of ethnic residential segregation. Copyright © 2008 John Wiley & Sons, Ltd. [source] Population change due to geographic mobility in Albania, 1989,2001, and the repercussions of internal migration for the enlargement of TiranaPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 6 2007Michalis Agorastakis Abstract Being a country in transition, Albania has sustained vast political and socio-economic changes over the past 15 years, mostly due to its engagement in democratisation and transformation to an open market economy. The pathway to transition has involved economic hardship and political unrest and has been accompanied by intense, large-scale, geographical mobility. This paper describes population change due to internal and international migration, 1989,2001, using Census data at district level. Its contribution is a technical one in applying a method that allows new estimates to be made of the scale of internal migration in Albania. Descriptive analysis of population changes in 36 Albanian districts, based on the last two censuses, lead to the identification of poles of attraction of internal migrants. Limited data concerning the 1989 Census and the 12 years between the censuses resulted in the creation of various indices that characterise internal migration, such as the Attraction and Expulsion Index stemming from the Origin,Destination Matrix of the districts. In addition an Index of Conservation of the population and an Index of External Migration were also derived at the district level. By considering internal and international migration as two separate phenomena, we emphasise their uniqueness in affecting population change in Albania. The District of Tirana, capital of Albania, absorbed the majority of the inflow of internal migrants. The latter part of the paper focuses on the population of Tirana as the county's major migration destination. Copyright © 2007 John Wiley & Sons, Ltd. [source] Suburbanisation in relation to education in the Tallinn metropolitan areaPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 4 2007Tiit Tammaru Abstract Significant changes occur in the social stratification order and spatial redistribution of population in countries in transition. One of the important dimensions in the changing social stratification order is related to the increased importance of education. Dominance of suburbanisation is an important dimension in spatial population change. The aim of the current article is to study these two important dimensions of social and spatial change by analysing suburbanisation with regard to the level of education of residential migrants in the Tallinn metropolitan area, Estonia. The study is based on census data from the year 2000 and it employs logistic regression to compare suburbanisers with stayers in Tallinn and its suburbs. The main findings indicate that suburbanisation reduces inequalities in the educational composition of people living in Tallinn and its suburbs on the one hand, but increases socio-spatial segregation within the suburbs on the other. Copyright © 2006 John Wiley & Sons, Ltd. [source] Rural population growth in Sweden in the 1990s: unexpected reality or spatial,statistical chimera?POPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 3 2006Jan Amcoff Abstract Although estimating rural population change at first glance seems simple, it in fact involves methodological difficulties and requires the accommodation of definitional ambiguities. This article addresses the matter of urban spillover in rural population development. Simply stated, ,urban spillover' here refers to how urban localities tend to push a ring of diffuse urban growth outwards as they expand in area. If constant delimitations of urban localities and rural areas are employed, their definitions will de facto change, and what is actually diffuse urban growth will be treated as rural. The effect of urban spillover in different methods of estimating rural population change are illustrated here using Swedish data, which are suitable for this purpose given their high spatial resolution. The data do not support the existence of any actual rural population growth in Sweden in the 1990s, apart from the effects of urban spillover. Copyright © 2006 John Wiley & Sons, Ltd. [source] The greying of resource communities in northern British Columbia: implications for health care delivery in already-underserviced communitiesTHE CANADIAN GEOGRAPHER/LE GEOGRAPHE CANADIEN, Issue 1 2005Neil Hanlon The delivery of ,rural' health care services has long confronted the geographic problems of distance, low user densities, low-order facilities and caregiver shortages. As a result, rural and remote communities across Canada have struggled with health care delivery. For rural and remote communities in resource hinterlands, population ageing driven by industrial restructuring presents a significant departure from past experience. Drawing on examples from northern British Columbia (BC), this paper examines this context of ageing in rural and remote locations with the purpose of highlighting impending challenges for health care service provision. In the first part of this paper, we provide a demographic overview of population change and ageing in northern BC. In the second part, we present data on the availability of services throughout the region to support seniors who age-in-place. Population ageing, in areas that have never dealt with this issue before, highlights not only important servicing questions but also important policy questions about how to provide for needs that the policy and community context are not presently equipped to meet. Ce n'est pas d'hier que la prestation de services de soins de santé en milieu «rural» doit composer avec les problèmes géographiques liés aux distances, à la faible densité d'usagers, aux établissements de bas ordre et à la pénurie de personnel soignant. C'est pourquoi, pour les collectivités rurales et éloignées du Canada, la prestation de soins de santé constitue un problème de longue date. Pour ces collectivités rurales et éloignées de l'arrière-pays industriel, le vieillissement de la population découlant de la restructuration industrielle représente une dérogation notable à l'ordre normal des choses. En s'appuyant sur des exemples du Nord de la Colombie-Britannique, le présent article examine le contexte du vieillissement en milieu rural et éloigné afin de faire ressortir les défis imminents à la prestation de services de soins de santé. La première partie de l'article présente un aperçu démographique du changement et du vieillissement de la population dans le Nord de la Colombie-Britannique. La seconde partie présente des données sur la disponibilité, dans la région, de services de soutien aux personnes âgées qui «vieillissent sur place». Pour les régions qui ne s'y sont pas encore attardées, le vieillissement de la population soulève non seulement d'importantes questions ayant trait à la prestation de services, mais aussi des questions de politiques visant la réponse à des besoins auxquels le contexte communautaire et le cadre de politique actuels ne répondent pas. [source] Documenting Loss of Large Trophy Fish from the Florida Keys with Historical PhotographsCONSERVATION BIOLOGY, Issue 3 2009LOREN McCLENACHAN arrecifes de coral; ecología histórica; directrices cambiantes; peces de arrecife; sobrepesca Abstract:,A loss of large vertebrates has occurred in aquatic and terrestrial ecosystems, but data to measure long-term population changes are sparse. Historical photographs provide visual and quantitative evidence of changes in mean individual size and species composition for groups of marine fish that have been targeted by sport fishing. I measured such trends for 13 groups of recreationally caught "trophy" reef fish with photographs taken in Key West, Florida, from 1956 to 2007. The mean fish size declined from an estimated 19.9 kg (SE 1.5) to 2.3 kg (SE 0.3), and there was a major shift in species composition. Landings from 1956 to 1960 were dominated by large groupers (Epinephelus spp.), and other large predatory fish were commonly caught, including sharks with an average length of just <2 m. In contrast, landings in 2007 were composed of small snappers (Lutjanus spp. and Ocyurus chrysurus) with an average length of 34.4 cm (SE 0.62), and the average length of sharks declined by more than 50% over 50 years. Major declines in the size of fish caught were not reflected in the price of fishing trips, so customers paid the same amount for a less-valuable product. Historical photographs provide a window into a more pristine coral reef ecosystem that existed a half a century ago and lend support to current observations that unfished reef communities are able to support large numbers of large-bodied fish. Resumen:,Una pérdida de vertebrados mayores ha ocurrido en ecosistemas acuáticos y terrestres, pero los datos para medir los cambios poblaciones a largo plazo son escasos. Las fotografías históricas proporcionan evidencia visual y cuantitativa de cambios en el tamaño individual promedio y de la composición de especies en grupos de peces marinos que han sido blanco de la pesca deportiva. Medí esas tendencias en 13 grupos de peces de arrecife capturados recreativamente como "trofeos" mediante fotografías tomadas en Key West, Florida, desde 1956 a 2007. El peso promedio de los peces declinó de unos 19.9 kg (ES 1.5) a 2.3 kg (ES 0.3), y hubo un cambio mayor en la composición de especies. Las capturas entre 1956 y 1960 estuvieron dominadas por meros (Epinephelus spp.) grandes, y otros peces depredadores eran capturados comúnmente, incluyendo tiburones con una longitud promedio de poco menos de 2m. En contraste, las capturas en 2007 fueron compuestas de pargos (Lutjanus spp. y Ocyurus chrysurus) pequeños con una longitud promedio de 34.4 cm (ES 0.62), y la longitud promedio de los tiburones declinó más de 50% en 50 años. La gran declinación en el tamaño de los peces capturados no se reflejó en los precios de los viajes de pesca, así que los clientes pagaron la misma cantidad por un producto menos valioso. Las fotografías históricas proporcionan una visión de un ecosistema arrecifal coralino prístino que existió hace medio siglo y proporcionan soporte a los comentarios actuales de que las comunidades arrecifales no explotadas son capaces de soportar numerosos peces de talla grande. [source] US state alcohol sales compared to survey data, 1993,2006ADDICTION, Issue 9 2010David E. Nelson ABSTRACT Aims Assess long-term trends of the correlation between alcohol sales data and survey data. Design Analyses of state alcohol consumption data from the US Alcohol Epidemiologic Data System based on sales, tax receipts or alcohol shipments. Cross-sectional, state annual estimates of alcohol-related measures for adults from the US Behavioral Risk Factor Surveillance System using telephone surveys. Setting United States. Participants State alcohol tax authorities, alcohol vendors, alcohol industry (sales data) and randomly selected adults aged , 18 years 1993,2006 (survey data). Measurements State-level per capita annual alcohol consumption estimates from sales data. Self-reported alcohol consumption, current drinking, heavy drinking, binge drinking and alcohol-impaired driving from surveys. Correlation coefficients were calculated using linear regression models. Findings State survey estimates of consumption accounted for a median of 22% to 32% of state sales data across years. Nevertheless, state consumption estimates from both sources were strongly correlated with annual r-values ranging from 0.55,0.71. State sales data had moderate-to-strong correlations with survey estimates of current drinking, heavy drinking and binge drinking (range of r-values across years: 0.57,0.65; 0.33,0.70 and 0.45,0.61, respectively), but a weaker correlation with alcohol-impaired driving (range of r-values: 0.24,0.56). There were no trends in the magnitude of correlation coefficients. Conclusions Although state surveys substantially underestimated alcohol consumption, the consistency of the strength of the association between sales consumption and survey data for most alcohol measures suggest both data sources continue to provide valuable information. These findings support and extend the distribution of consumption model and single distribution theory, suggesting that both sales and survey data are useful for monitoring population changes in alcohol use. [source] Changes in abundance of Vespula germanica and V. vulgaris in EnglandECOLOGICAL ENTOMOLOGY, Issue 1 2001Michael E. Archer Summary 1. Thirteen time series, varying from 17 to 27 years, of the abundance of Vespula germanica and V. vulgaris from lowland England are examined. The time series depend on either spring queens and workers taken in Malaise or suction traps, or collected colonies. 2. During the late 1970s and early 1980s, the abundance of V. germanica declined abruptly but that of V. vulgaris did not. 3. During the early 1980s, the 2-year cycle of annual abundance of V. vulgaris changed to a nearly perfectly damped pattern of annual abundances. 4. The most likely factor causing these population changes was the increased use of pesticides acting directly by killing the wasps and indirectly by reducing their food resources. 5. The difference in response of the two species to increased pesticide use may be related to a difference in foraging ability. [source] POPULATION AND EMPLOYMENT CHANGES IN REGIONAL AUSTRALIAECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 1 2007ANNE M. GARNETT Regional Australia has experienced significant changes in population and employment since the early 1990s. Evidence regarding these changes has often been anecdotal, with references in political and media spheres to a ,Sea Change' or ,Tree Change'. There has also been considerable public discussion about the effect that the structural changes and misfortunes within the agricultural sector have had on localities in rural regions. The purpose of this paper is to provide and analyse data on regional population and employment changes since the early 1990s. It will also examine the role that the agricultural sector may have had in these changes. This will provide a basis for informed debate and analysis of population changes in regional Australia and the causes and implications of these changes. [source] Seasonal population changes of five parasitoids attacking the scale insect Nipponaclerda biwakoensis on the common reed, with special reference to predation by wintering birdsENTOMOLOGICAL SCIENCE, Issue 4 2005Shuji KANEKO Abstract Seasonal changes in the abundance of five species of hymenopterous parasitoids (four species of Encyrtidae and one species of Eulophidae) attacking the scale insect Nipponaclerda biwakoensis on the common reed were investigated for 2 years in Lake Biwa, with special reference to predation by the reed bunting, Emberiza schoeniclus, during winter. The scales settled on reed shoot stems under sheath leaves, passing through three discrete generations per year. The abundance of adult female scales increased exponentially from July (first generation) to December (third generation). Adult female scales of the third generation overwintered on reed shoots. During winter, female scale abundance dramatically declined, whereas the number of predation marks made by reed buntings using their bills on reed sheath leaves increased. The generations of all five parasitoids were synchronized with the host scale generations, and the five parasitoids overwintered as larvae inside the scale bodies. The abundance of parasitized scales and parasitoid adults emerging from the scales also increased from July to December, but greatly decreased during winter. The overall parasitism rate of the female scales remained at relatively low levels (less than 40%) throughout the year, including before and after winter. A bird exclusion experiment revealed that the dramatic winter decrease of the abundance of the scale and its five parasitoids was due to intensive and non-selective predation by the buntings on unparasitized and parasitized scales. Additionally, the proportion of immature parasitoids removed by birds varied between the five parasitoid species. Thus, seasonal population changes of the five scale parasitoids are considerably affected by bird predation on overwintering immature parasitoids. [source] Elevated atmospheric CO2 affects soil microbial diversity associated with trembling aspenENVIRONMENTAL MICROBIOLOGY, Issue 4 2008Celine Lesaulnier Summary The effects of elevated atmospheric CO2 (560 p.p.m.) and subsequent plant responses on the soil microbial community composition associated with trembling aspen was assessed through the classification of 6996 complete ribosomal DNA sequences amplified from the Rhinelander WI free-air CO2 and O3 enrichment (FACE) experiments microbial community metagenome. This in-depth comparative analysis provides an unprecedented, detailed and deep branching profile of population changes incurred as a response to this environmental perturbation. Total bacterial and eukaryotic abundance does not change; however, an increase in heterotrophic decomposers and ectomycorrhizal fungi is observed. Nitrate reducers of the domain bacteria and archaea, of the phylum Crenarchaea, potentially implicated in ammonium oxidation, significantly decreased with elevated CO2. These changes in soil biota are evidence for altered interactions between trembling aspen and the microorganisms in its surrounding soil, and support the theory that greater plant detritus production under elevated CO2 significantly alters soil microbial community composition. [source] Extracting long-term patterns of population changes from sporadic counts of migrant birdsENVIRONMETRICS, Issue 5 2010Joanna Mills Flemming Abstract Declines of many North American birds are of conservation concern. For almost 40 years, experienced birders have kept daily counts of migrant landbirds during visits to Seal and Brier Islands, both of which are off Nova Scotia's southern tip. Here we assess the utility of Generalized Additive Models (GAMs) to extract patterns of population change of a common migrant to Seal Island, the Ruby-crowned Kinglet, while controlling for other influences including season, weather and effort. We also demonstrate, using counts of the Kinglet from Brier Island as well as counts of another common migrant, the Yellow-rumped Warbler, how our GAM methods can combine data from different geographic areas or distinct species. Most existing analyses of similar long-term data sets have used linear models to estimate trends. Our results and comparisons suggest that GAMs are a powerful way of extracting more information from such data. Copyright © 2009 John Wiley & Sons, Ltd. [source] Contrasting population changes in sympatric penguin species in association with climate warmingGLOBAL CHANGE BIOLOGY, Issue 3 2006JAUME FORCADA Abstract Climate warming and associated sea ice reductions in Antarctica have modified habitat conditions for some species. These include the congeneric Adélie, chinstrap and gentoo penguins, which now demonstrate remarkable population responses to regional warming. However, inconsistencies in the direction of population changes between species at different study sites complicate the understanding of causal processes. Here, we show that at the South Orkney Islands where the three species breed sympatrically, the less ice-adapted gentoo penguins increased significantly in numbers over the last 26 years, whereas chinstrap and Adélie penguins both declined. These trends occurred in parallel with regional long-term warming and significant reduction in sea ice extent. Periodical warm events, with teleconnections to the tropical Pacific, caused cycles in sea ice leading to reduced prey biomass, and simultaneous interannual population decreases in the three penguin species. With the loss of sea ice, Adélie penguins were less buffered against the environment, their numbers fluctuated greatly and their population response was strong and linear. Chinstrap penguins, considered to be better adapted to ice-free conditions, were affected by discrete events of locally increased ice cover, but showed less variable, nonlinear responses to sea ice loss. Gentoo penguins were temporarily affected by negative anomalies in regional sea ice, but persistent sea ice reductions were likely to increase their available niche, which is likely to be substantially segregated from that of their more abundant congeners. Thus, the regional consequences of global climate perturbations on the sea ice phenology affect the marine ecosystem, with repercussions for penguin food supply and competition for resources. Ultimately, variability in penguin populations with warming reflects the local balance between penguin adaptation to ice conditions and trophic-mediated changes cascading from global climate forcing. [source] Interspecific differences in population trends of Spanish birds are related to habitat and climatic preferencesGLOBAL ECOLOGY, Issue 1 2008Javier Seoane ABSTRACT Aim, Animal monitoring programmes have allowed analyses of population trends, most of which now comment on the possible effect of global climate change. However, the relationship between the interspecific variation in population trends and species traits, such as habitat preferences, niche breadth or distribution patterns, has received little attention, in spite of its usefulness in the construction of ecological generalizations. The objectives of this study were: (1) to determine whether there are characteristics shared among species with upwards or downwards trends, and (2) to assess whether population changes agree with what could be expected under global warming (a decrease in species typical of cooler environments). Location, The Spanish part of the Iberian Peninsula (c. 500,000 km2) in the south-western part of the Mediterranean Basin. Methods, We modelled recent breeding population changes (1996,2004), in areas without apparent land use changes, for 57 common passerine birds with species-specific ecological and distributional patterns as explanatory variables. Results, One-half of these species have shown a generalized pattern towards the increase of their populations, while only one-tenth showed a significant decrease. One half (54%) of the interspecific variability in yearly population trends is explained considering species-specific traits. Species showing more marked increases preferred wooded habitats, were habitat generalists and occupied warmer and wetter areas, while moderate decreases were found for open country habitats in drier areas. Main conclusions, The coherent pattern in population trends we found disagrees with the proposed detrimental effect of global warming on bird populations of western Europe, which is expected to be more intense in bird species inhabiting cooler areas and habitats. Such a pattern suggests that factors other than the increase in temperature may be brought to discussions on global change as relevant components to explain recent changes in biodiversity. [source] | ||||||||||||||||||||||||||||||||||