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Geographers have long been interested in population and its interactions with Earth's natural systems. In recent decades it has become continually more apparent that steady population growth, coupled with increasing affluence, has wreaked havoc on many natural systems, has caused the decline and even extinction of many species of plants and animals that share the planet with us, has changed our global climate, and has exacerbated numerous other problems. Now populations in some countries, including Japan, Russia, and Germany are, or soon will be, starting to decline. This trend would seem to bode well for the planet, but the depopulation of some rich countries may be drowned out by the continuing wave of population growth in the United States and in many poor countries., HENDERSON (2010) WROTE THAT 'I believe we are at the most important moment for clear, logical thinking and communication about geographical issues and their significance in revealing what it means [...]

The emergence of the eugenic movement in the late nineteenth century reflected a concern with the perceived negative consequences of differential fertility for the quality of human populations. As theory, [...]

The differences at local authority district level in England and Wales is studied in three parts namely, basic descriptive statistics, comparison of the local authority districts as a proportion of their national totals, and more complex multiple regression analysis. The implementation of the findings of the analyses is assessed and recommendations are put forward to help improve the mid-year estimates in the following decade.

Demographic transition theorists postulate a post-transition steady state predicated on the nuclear family. This study reveals that other family types - community and anomic/polygynous - will, if they persist, produce different steady states at higher levels of infant mortality and fertility. Only if family type changes as countries modernize will the transition theorists' post-transition steady state be achieved.

This article explores a reparameterization of a 2 x 2 table. This reparameterization turns out to be useful in considering the consequences of amalgamating several 2 x 2 tables. A formal theorem is derived that permits characterization of Yule's association paradox. The same theorem also permits discussion of the likely direction of error incurred when using capture-recapture methods to estimate the size of a population. This has implications for the 'wily trout' argument in the census correction controversy. KEY WORDS: Capture-recapture; Census; Reparameterization; Simpson paradoxes., 1. INTRODUCTION The amalgamation of 2 x 2 tables has been a subject of considerable work and puzzlement. The well-known paradoxes (Yule, Simpson, etc.) are symptomatic of the difficulty. The [...]

Plato observed it, the old testament taught it, and Thomas Robert Malthus feared it. It has been called the principle of plenitude, which 'presupposes a richness, an expansiveness of life, [...]

In contrast to a common hypothesis, renewed population growth in the central urban areas, the regained attractivity of the near suburbs and the significant drop in new construction activity have not slowed down the spread of population over the French territory in the last decade. Centrifugal forces remain predominant over centripetal forces. Where residential mobility in general has diminished for all age groups and for all socio-professional categories, the scarcity situation on the real-estate market and the slowing-down of the 'de-cohabitation' of young people have not increased the occupancy rate of housing. In Paris, because they want more living space, families with children continue to leave the central zones in favour of the periphery, whereas young unmarried couples without children locate in the centre of the agglomeration. Still this movement is socially differentiated. For the well-to-do, the relative share of centrifugal movements has diminished, whereas the low income classes are increasingly obliged to move away from the centre. Rather than a 'retour au centre' one should speak for the Paris region (Ile-de-France) of a slowing down of the departure toward the periphery. But this does not challenge the general process of the spreading out of housing across a region where over 90% of the population is urban according to the definition of INSEE, the French national statistical office.

There are two major shortfalls in Tyson's track-count survey method as revealed by the nocturnal movements of white-tailed deer which shows that density alone may affect deer behaviour regardless of how much and what kind of forage there is. Movements of deer display a difference in nocturnal rates of travel (NRT), distances between extreme nocturnal locations (DBE), and frequencies of nocturnal activity (ACT), but not distance between locations at sunset and sunrise the following day (DFL) or frequency of road crossing (FRC). Modifications in Tyson's original formula are provided.

There are grounds for reconsidering the United Nations' population projections for Peru. These projections assume that fertility will continue to decline after 1990 in a smooth and uninterrupted manner, but they ignore several factors related to recovery from the economic and political crises of the 1980s that could significantly alter the pace of decline. The alternative projections we present consider the possibility that Peru's fertility decline will temporarily slow. This alternative hypothesis is conservative in the sense that increases in birth rates are not anticipated, but substantial differences in population size and age structure materialize nonetheless. Moreover, these differences have important implications for future planning in terms of the number of children needing primary health care and education and the number of young adults seeking first-time employment.

It is sometimes said that there is no population problem in the United States because the U.S. fertility rate is approximately at the replacement level of 2.1 children per woman. However the population of the United States increased in 1992 by approximately three million people. There are two major causes of continued population growth even when fertility is approximately at the replacement level. One is population momentum; the other is immigration. This paper examines what must be done if we want to achieve zero growth of the population of the United States immediately, without the long delays caused by population momentum.

Small area population projections present problems involving methodological accuracy and bias that are absent for state and national data. Census tracts, traffic analysis zones and zip code areas are readily affected by data availability and quality, shifting boundaries and population size. It is shown that for such projections, no accurate prediction can account for overall bias., 1. INTRODUCTION Population projections at the state and national levels have been made for many years, but such projections are of limited use for planning, budgeting, and analysis at the [...]

The geological history of the Earth is replete with examples of animals proliferating to numbers that exceeded the ability of their environments to provide support. Enormous numbers and widespread distributions of many animals sometimes have been followed by drastic reductions in numbers of individuals and even by complete extinction of species. Humans of many nations are following the same trend of population growth beyond the ability of resources to insure adequate food, clothing, shelter, safety, and transport and beyond the ability of Earth to accommodate the wastes. Human population is now 5.4 billion, with a present doubling time estimated at about 35 years. Is this uncontrolled proliferation also to be followed by severe reduction or even extinction? If not, how may human population be stabilized or reduced to a level commensurate with resources and waste disposal--more effective contraceptives, increased abortion, high taxes on procreation? An approach more effective than religion or political control may be through better education (increased percentage literacy) that is known to correlate with lower birth rates and increased national income per capita in the about 167 nations of the world. If leadership cannot soon rise to face this situation, human inhabitation of the Earth may become much more complicated in the not distant future.

The world's population -- with today's 6.1 billion already more than twice the 1950 figure -- is likely to grow by another 3 billion in the next half-century, according to [...]

Population cycles have long fascinated ecologists. Even in the most-studied populations, however, scientists continue to dispute the relative importance of various potential causes of the cycles. Over the past three decades, theoretical ecologists have cataloged a large number of mechanisms that are capable of generating cycles in population models. At the same time, statisticians have developed new techniques both for characterizing time series and for fitting population models to time-series data. Both disciplines are now sufficiently advanced that great gains in understanding can be made by synthesizing these complementary, and heretofore mostly independent, quantitative approaches. In this paper we demonstrate how to apply this synthesis to the problem of population cycles, using both long-term population time series and the often-rich observational and experimental data on the ecology of the species in question. We quantify hypotheses by writing mathematical models that embody the interactions and forces that might cause cycles. Some hypotheses can be rejected out of hand, as being unable to generate even qualitatively appropriate dynamics. We finish quantifying the remaining hypotheses by estimating parameters, both from independent experiments and from fitting the models to the time-series data using modern statistical techniques. Finally, we compare simulated time series generated by the models to the observed time series, using a variety of statistical descriptors, which we refer to collectively as 'probes.' The model most similar to the data, as measured by these probes, is considered to be the most likely candidate to represent the mechanism underlying the population cycles. We illustrate this approach by analyzing one of Nicholson's blowfly populations, in which we know the 'true' governing mechanism. Our analysis, which uses only a subset of the information available about the population, uncovers the correct answer, suggesting that this synthetic approach might be successfully applied to field populations as well. Key words: blowflies; density dependence; fitting mechanistic models to time-series data; inverse problem; Lucilia cuprina; mechanistic population models; modeling population cycles; population cycles, determining the causes of; statistical time-series analysis; structured population models; time-series models., INTRODUCTION The population densities of many species can fluctuate nearly periodically over time, with periods that cannot be explained simply by seasonal variation . These regular, large-amplitude oscillations invite explanation [...]

Research is presented concerning the influence of the decreasing rate of growth of global productivity and population on integrated assessment models of climate change. The abatement of greenhouse gases is discussed.

Americans have been moving to the suburbs for decades; however, during the 1970s, there was a perceptible back-to-the-city movement. A study reveals that, in truth, this repopulation of U.S. city centers was not part of a long-term trend, and in fact is due for near-term reversal. The misinterpretation grew from the fact that the absolute number of some groups grew in city centers; however, the percentages of these groups did not not shift. Projections indicate that the percentages will tend downward even more in the years ahead, as household-making groups begin to comprise smaller percentages of the U.S. population.

Issues concerning Britain's increase in population, and the effect of this on housing demand, are discussed. The need for the government to encourage house-building in the south of England, an area of population growth and high housing need, is emphasized.

Research is presented describing the study of population trends and the dramatic implications on economic and social structures caused by a declining birthrate and increase in life expectancy during the 21st century.