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At least 19 recordsLinked to original sources
PubMed1964

THE MUSHROOM CROWD: SOCIAL AND POLITICAL ASPECTS OF POPULATION PRESSURE.

The meaning of population pressure is discussed and, with the help of a formula, its five main components (people, rate of increase of people, food-producing acreage, protein nutrition and industrialization) are analyzed.Factors which have eased population pressure in the past are considered under the headings of political violence (war and genocide), natural disaster (famine and disease), and social action (increased local protein supply, emigration, industrialization and birth control).Birth control is the first prerequisite to an easing of population pressure; the effectiveness of the Japanese and the Indian programs is discussed.The crippling burden of preventable disease, shown to be a major obstacle to the development of sophisticated industries, presents a challenge to Western medical men who so far have done little to meet it.

Agaricales↗
PubMed1985

A quantitative model of population pressure and its potential use in development planning.

An attempt is made to develop a quantitative model of the concept of population pressure, using the example of population pressure on land resources in agricultural societies. "The model shows that environmental quality is tied to population growth and that population pressure does not bear relationship with population density." The implications of the findings for development planning are considered. (summary in IND)

Agriculture↗
PubMed2005

Contact guidance in human dermal fibroblasts is modulated by population pressure.

Morphogenesis is underpinned by orientated cell division, motility and growth. The substratum for migrating cells in vivo comprises either extracellular matrix or the surfaces of adjacent cells and both are believed to inform the dynamic behaviour of adherent cells through contact guidance. Collisions between migrating cells in vitro can induce the phenomena of contact inhibition of locomotion and division, suggesting that their sensitivity to substratum-derived cues may also be influenced by population density. In the present study dermal fibroblasts, which are known to be motile in culture and are fundamental to the organization of the extracellular matrix, were used to examine the influence of population pressure on the ability of substratum topography to induce contact guidance. The findings suggest that sensitivity to substratum-derived morphogenetic guidance cues, as revealed by alignment of cells to microtopography, is modulated by population pressure.

Cell Adhesion↗
PubMed1980

Population pressure and land use change: from tree crops to sawah in Northwestern Kalimantan, Indonesia.

The author describes the role of population pressure in the current transition from tree crops to wet rice cultivation (sawah) in Northwestern Kalimantan, Indonesia. He contends that this change is occurring "because the senescent trees no longer produce enough commodities to exchange for rice to feed an enlarged population." The historical background is described, policies of the Indonesian government are discussed, and data are presented on the rate of population growth

Agriculture↗
PubMed1985

Population pressure, mobility, and socio-economic change in mountainous environments: regions of refuge in comparative perspective.

This paper examines demographic and socioeconomic forces in high isolated parts of the world. These regions were not always isolated; they were once the centers of their own particular worlds which, in some cases, were complex civilizations. It is their relegation to the very periphery of the modern world that is the principal theme of this paper. Population migration, both into and out of these areas, has played a vital role in linking mountainous regions to the wider world. Particular attention is paid to the part played by the traditional mobility patterns and by the resource base of the mountains in the transformation of integral, self-sufficient cultures into dependent, subservient part-cultures, the regions of refuge. The effect of population pressure and the development of outmigration from the Andes of Peru is examined first and the analysis extended to the highlands of Papua-New Guinea and to several regions in the Himalayan arc to provide the background for a comparative study of regions of refuge.

Age Distribution↗
PubMed2005

Evolution of human longevity, population pressure and the origins of warfare.

In a protected environment, humans have the longest lifespan of all primates. However, during the emergence of Homo sapiens from pre-hominids, the expectation of life at birth would have been quite low. On the basis of reasonable assumptions, an average expectation of life of less than 20 years is sufficient to maintain a population of hunter-gatherers. As individuals became better adapted to their environment, the mortality rate would gradually decrease, and this would result in the survival of more offspring to adulthood. Thus, the population will increase, and one of the consequences in human evolution is the migration of human communities to many new habitats. The development of agriculture provided a more reliable source of food, and stimulated further the increase in population size. Villages became towns, and then cities, states and empires arose which had very large populations, and competed for land and other resources. Armies were raised and were often at war. All this was due to population pressure, as Malthus had realised more than 200 years ago. However, neither he, nor any of the others who discussed warfare, understood that the demographic changes that produced large human populations was a steady increase in the expectation of life at birth. This inevitably occurred at the same time as man gradually gained more control over his environment, and achieved far more reproductive success than is seen in hunter-gatherers living in a harsh, stressful environment.

Agriculture↗
PubMed2001

Population pressure and fertility in pre-transition Thailand.

Before the demographic transition in Thailand, fertility was high, but not uniformly so. As in other pre-transition settings, Thai fertility responded to pressures and opportunities created by socioeconomic structure and land availability. Drawing upon provincial data from the 1947 and 1960 censuses of Thailand, we find a strong 'frontier effect' on Thai fertility in the 1950s. Fertility was higher in sparsely settled frontier provinces and lower in provinces with higher population density relative to cultivatable land. This finding is robust and holds up with controls for agricultural employment, land quality, and the sex ratio (an indicator of sex-selective migration). The effect of population pressure lowers the likelihood of marriage and of marital fertility. The findings from Thailand are consistent with the research of Easterlin on the nineteenth century United States and with other pre-transition societies. We suggest how demographic transition theory might be broadened to include fertility dynamics in pre-transition societies.

Fertility↗
PubMed1989

Fertility decline in Mauritius: the role of Malthusian population pressure.

Mauritius provides 1 of the outstanding cases of modern fertility reduction in the Third World, yet there has been little analysis and virtually no comparative assessment of this important demographic progression. It is argued that fertility decline in Mauritius has been hindered by cultural composition, assisted only modestly by ongoing development, but aided significantly by family planning program intervention and by a remarkable wide recognition at government and individual levels of the diseconomies associated with population growth in a congested society; comparisons are made with other densely peopled, small islands. Spatial variations in fertility and in family planning activity are slight, but Western economic theories of fertility are found to be helpful in interpreting significant temporal fluctuations.

Africa↗
PubMed1994

Population pressure rising.

Even though the ESCAP region has been successful in slowing population growth, Asia will account for half of the global population increase every year, or about 1 billion persons in the next quarter century, according to a new report by the Asian Development Bank (ADB). That report, entitled "Population Policy Paper," states that Asia will be the global center of population aging largely because of big increases in the number of persons over the age of 65 in China, Japan and the region's newly industrializing economies. "By the year 2000, 86% of the world's aged will be in the Asia-Pacific region and by the year 2025 there are projected to be 687 million persons over the age of 65 in the region, placing unprecedented strains on economic and social systems far beyond what traditional extended family networks can absorb," the paper says. But the report also considers other aspects of overall population increase. "The prospect of an additional billion or so people in Asia over the next 25 years is daunting, since the implications for poverty, economic growth, unemployment and environmental quality are immense," it adds. The region's economies will have to scramble to generate jobs and livelihoods for tens of millions of young people for the next several decades. Rural-to-urban migration trends threaten the collapse of urban infrastructure, with the social tensions and political instability that such troubles bring, the report states.

Asia↗