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1.
Jowett AJ 《GeoJournal》1986,12(4):349-363
Since 1949 China's population has increased by 500 million and thereby grown at an average rate of 2 % per year. Annual growth rates have varied dramatically, falling from 3.3 % in 1963 to 1.2 % in 1979 and registering a population decline of 13.5 million in the famine years of 1960/61. China's demographic disaster in 1958/61 ranks as one of the most devastating in the history of the world. Chinese leaders have oscillated between pro- and anti-natalist policies. However, in the 1970s the government launched its third, its most intensive and to date its most successful family planning programme. So succesful that the total fertility rate declined from 6.4 in 1968 to 2.2 in 1980 and the level of contraceptive use in China was raised to the levels currently experienced in the Developed World. Despite the high rate of contraceptive prevalence, induced abortion is still extensively used to prevent unplanned births. The extent to which China's birth control programme has been implemented on a voluntary, coercive or compulsory basis is open to question. A rapid increase in the age of marriage and a substantial improvement in female education have made important contributions to the decline in fertility. Large differences in fertility exist between rural and urban China, reflecting significant differences in the average age of marriage and the very marked difference in educational attainment between the cities and the countryside. Whether the government directed family planning programme or socio-economic development has had the greatest impact on the decline in fertility, is under discussion. Whatever the motive force, the pace of demographic modernisation has been impressive and by international standards China now enjoys advanced levels of demographic development at an early stage of economic development.Abbreviations CMP-SPRCP-75-114
China Mainland Press, Survey of People's Republic of China Press 1975, No. 114.
- FBIS-CHI-83-112
Foreign Broadcast Information Service, Daily Report, China, 1983, No. 112.
- JPRS-CPS-85-012
Joint Publications Research Service, China Report, Political, Sociological and Military Affairs, 1985, No. 12.
- SWB/FE/6246/BII
Summary of World Broadcast, Far East, No. 6246, section BII. 相似文献
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Croatia is a Central European and Mediterranean state, located in contact with and under the influence of various spheres of civilization, which for centuries have penetrated and conflicted on and around the territory of Croatia. Such a position has resulted in various influences which did not always have a positive effect on the development of Croatia. The gradual narrowing and decrease of the Croatian ethnic territory, as well as the presence of national minorities in it, was also a result of the aforementioned position and outside influences (ulji 1993/1994).The demographic structure of Croatia indicates a series of specificities which were primarily conditioned by the historical development of Croatia and which is particularly expressed in constant emigration since the end of the nineteenth century, the relatively large direct and indirect losses to the population during and immediately after the First and Second World Wars, emigration as a type of population movement in all inter-census periods after 1945, the appearance of a natural decline and the aging of the population on almost one half of the state territory. 相似文献
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"Jiangsu (Kiangsu) Province [China] is located in the lower reaches of the Yangtze River which divides it into two parts, South Jiangsu and North Jiangsu. The area of the province is 102,000 sq. km with a population of 60,521,114 and a density of 605 per sq. km in 1982. The area of Jiangsu is slightly larger than that of Hungary (93,000 sq. km). But the population is 5.7 times and the density of population 5.2 times larger than those of Hungary. This paper states the tendency of population growth, the geographical distribution and present condition of urban and rural population, discussing briefly the rational redistribution of [the] population of Jiangsu." 相似文献
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We consider the main population of cosmic voids in a heirarchical clustering model. Based on the Press-Schechter formalism modified for regions in the Universe with reduced or enhanced matter densities, we construct the mass functions for gravitationally bound objects of dark matter occupying voids or superclusters. We show that the halo mass functions in voids and superclusters differ substantially. In particular, the spatial density of massive (M ~ 1012 M ⊙) halos is appreciably lower in voids than in superclusters, with the difference in the mass functions being greater for larger masses. According to our computations, an appreciable fraction of the mass of matter in voids should be preserved to the present epoch in the form of primordial gravitationally bound objects (POs) with modest masses (to 10% for M PO < 109 M ⊙) keeping baryons. These primordial objects represent “primary blocks” in the heirarchical clustering model. We argue that the oldest globular clusters in the central regions of massive galaxies are the stellar remnants of these primordial objects: they can form in molecular clouds in these objects, only later being captured in the central regions of massive galaxies in the process of gravitational clustering. Primordial objects in voids can be observed as weak dwarf galaxies or Lyα absorption systems. 相似文献
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Kawabe H 《GeoJournal》1980,4(3):191-198
All data obtained from vital statistics and the fertility survey indicate that the population of Japan will have a heavy burden of increasing old ages in the near future, because the attitude toward the number of children among Japanese women is to have fewer children (but not to have no children) and because it is anticipated that this attitude will not last for a good number of years in the future. This is one of issues discussed in recent Japan as population problems in the Aging Society.Another issue is population problems in the High Density Society. This issue is discussed in relation to unbalanced land utilization, air and water pollution, destruction of village life etc., brought about by the over-congestion in the metropolitan areas areas and depopulation in rural areas.One of the aims involved in the regional development plan of Japan is to solve the problems occured by the uneven distribution of population. The Third Comprehensive National Development Plan published in 1977 states that the central aim of this plan is to undertake the reorganization of population distribution by the development of attractive local cities, towns and villages where enough educational and employment opportunities are provided to make a best use of the desirable characteristics of the region, maintaining the present profitable feature of the areas and comfortable living conditions for people.The original of this article is the paper submitted to the International Conference on Population Problems and National Development, held at Seoul, Korea in November, 1978, sponsored by the Institute of Population Problems, Seoul, Korea. 相似文献
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Oasis is not only the most concentrated area of human activities in arid region but also the largest area where artificial disturbances occur at the regional scale. The Jinta Oasis is a very typical artificial oasis in arid region of China and is set as one of the national land resource developing and representative areas in China. With the continuous increase in population and livestock number in Jinta Oasis, such severe problems of environmental degradation as serious land pollution and desertification, water environmental degradation, and vegetation degeneracy occur within the whole oasis. 相似文献
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《Geoforum》1988,19(3):263-276
In this year of the Bicentenary of European settlement in Australia, it must be remembered that humans have been present in Australia for at least 40,000 years, longer than in the Americas or the Pacific island countries. The year 1788, however, marks a discontinuity in the population history and geography of Australia, and this review considers past trends and contemporary dynamics in order to illustrate the population issues confronting Australia in her Bicentenary year. 相似文献
13.
哲杜斯贝是一种以高丰度和低物种分异度为显著特征、在全球广泛独立分布的小嘴贝类。笔者对华南台地相和台间盆地相5个含哲杜斯贝类上泥盆统剖面进行沉积环境和埋藏特征研究,确定华南哲杜斯贝类的原生沉积环境为台地的正常浅水,这与美国和摩洛哥生长在冷泉环境中的哲杜斯贝不同,表明其既可在浅海环境中生长,也可以在冷泉环境中生长,具有较强的生态可塑性。台地相(原地埋藏)的3个哲杜斯贝种群具有以下特征:(1)均呈现出壳体呈层状紧密堆积、集群生长特点,丰度极高,并且有相当数量的个体呈现出由于拥挤生长而导致的壳体生长畸形现象;(2)缺乏其他底栖后生生物,显示了极低的生物多样性;(3)壳体大小—频率分布和生存曲线揭示了3个哲杜斯贝种群都具有非常低的幼年期死亡率特点,同时同一介壳层内哲杜斯贝个体大小均一,表明绝大多数的个体能够达到或接近自然寿命后死亡。上述证据表明,哲杜斯贝具有密集群居生活的习性,其生活在一个独特的、不适合其他后生底栖生物生存的环境。 相似文献
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Spatiotemporal changes in population distribution and socioeconomic development in China from 1950 to 2010 总被引:1,自引:0,他引:1
Complex factors, including those associated with human and natural geography, have contributed to a longstanding imbalance in the relationship between population distribution and socioeconomic development in eastern and western China. Applying the population distribution structure index, the Gini coefficient of population distribution, and analysis of the movement of the population center of gravity and spatial autocorrelation, this study simultaneously analyzes the spatial characteristics of population density in China and the trends in its temporal and spatial variation from 1950 to 2010. It was found that while China’s population distribution has increasingly balanced development, the overall pattern of the spatial distribution has not changed significantly. Although the “Hu Huanyong Line” is still a valid representation of the country’s population distribution, the population distribution in parts of Gansu, Ningxia, and Inner Mongolia has extended the boundary of the Hu Huanyong Line. The Chinese population has experienced a trend of movement towards the west. While the congruence between the population distribution and economic development of the country as a whole was relatively low, it was relatively high in the northeast and the relationship is steadily improving. Compared with the eastern and central regions, the western region has experienced a fluctuating and weakening trend. 相似文献
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Known coal reserves in China are about 1031 billion tonnes, while the predicted resources are 3800 billion tonnes. China is currently the world's largest coal producer, with over 1 billion tonnes'production in 1990. It is not surprising to discover, therefore, that coal is not only geographically widespread in the country but also occurs in every stratigraphic interval upwards from the Devonian (and even earlier) and is found in almost every conceivable depositional setting. With seams over 200 m thick in some basins, Chinese coals offer many geological as well as mining challenges . 相似文献
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中国大陆的组成、结构、演化和动力学 总被引:35,自引:2,他引:35
中国大陆是由众多微陆块和小陆块组合而成的复合大陆,微、小陆块的软碰撞和多旋回缝合以及由此而产生的多旋回复合造山带、多旋回叠合盆地和多彷回构造岩浆成矿作用是其非常重要的特征。中国大陆具有清晰的多旋回分阶段演化过程和复杂的多层次镶叠式与立交桥式结构。古生代以来,中国大构造发展受古亚洲洋、特提斯洋、太平洋三大全球性动力学体系之控制。其主要动力过程表现为冈瓦纳裂离、陆块北移、褶皱带南迁、亚洲增生。 相似文献
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伤齿龙类是手盗龙类中较为独特的一支, 时代从中侏罗世到晚白垩世, 主要分布于亚洲(东部和中部)以及北美地区。本文基于前人的研究成果, 结合新标本, 对中国伤齿龙类的系统分类、骨骼形态、骨组织、系统发育关系和古生物地理等方面进行了全面深入的评估与探讨。 相似文献
18.
Despite substantial rural-urban migration, 38.1 percent of the population of Poland still live in the countryside and the
total numbers are only 0.9mln fewer than in 1946. At present the rural population is increasing and the rate of natural increase
(though falling) is higher than in the towns though the productive age group is smaller. However, these human resources are
not being properly used and the results can be seen in terms of economic inefficiency, low living standards and a high level
of state support. Loss of jobs in factories and state farms results in welfare payments by the state and considerable 'hidden
unemployment' on small family farms where profitability is constrained by inefficient use of labour. Poverty among the rural
population is evident through a collapse of house building and considerable domestic overcrowding. However, conditions vary
considerably across the country and this must be reflected in the economic and social policies drawn up for the new administrative
regions introduced in 1999.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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The exploration of the spatial association between Medicare physician spending and population densities and sizes could possibly facilitate the investigation of the causal mechanisms beneath the variation in medical care. We acquired the U.S. Medicare physician expenditures and regional demographic and geographic data in 2006 from the Dartmouth Atlas of Health Care. Six geographic units—states, counties, Hospital Referral Regions, Hospital Service Areas, Metropolitan Statistical Areas, and state non-Metropolitan Statistical Areas—were used as units of study. Pearson correlation analysis, multivariable regression, and partial correlation analysis were employed. Among six geographic units, Pearson correlation coefficients between Medicare physician expenditures and logarithmic population densities ranged from 0.42 to 0.63 (p < 0.05 for all), and between the expenditures and logarithmic population sizes from 0.31 to 0.65 (p < 0.05 for all). When population health, differential demand, market structure, and data reporting bias were controlled, population densities and sizes were positively associated with Medicare physician expenditures in most models. Population densities and sizes could explain considerable amounts of regional variation in Medicare physician spending. We concluded that Medicare physician spending was contingent on population densities and sizes. Because population densities and sizes are produced by more fundamental qualities such as natural environments and resources and thus are not easily manipulated, they are suggestive in health policy studies. Further research might investigate population distribution associated properties such as geographic distribution of health care resources, spatial dynamics of medical technology distribution, and cultural and psychological factors. 相似文献
20.
The paper attempts to make an assessment of the health state of the Romanian population during the transition period; the
evolution of the health indicators, analyzed in the European context, shows the precarious health state of the Romanian population,
in comparison both to Western countries and to the countries which are crossing a transition phase themselves. The values
of the health indicators by region also show inequalities of health, the north-western and south-eastern areas of the country
having to face serious problems.
The reduction of living standard, the low quality health services, together with other factors associated with lifestyle seem
to be responsible for the deterioration of the health state of the Romanian population. The introduction of adequate health
and social policies in the following period could bring about an improvement of the situation.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献