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1.
Recent long‐term demographic projections suggest a fast deceleration of global population growth and the eventual peaking of world population later in this century at about 9.2 billion, roughly 50 percent above the present level. Some low‐income and food‐insecure countries, however, have projected populations in 2050 that are multiples of present ones. In some of these countries agriculture must play a leading role in their development efforts because they have high economic dependence on that sector. For those among them that have scarce agricultural resources, a prima facie case can be made that the high population growth rates projected may not be compatible with the development potential offered by such resources. Their demographic projections may need to be revisited, taking into account such inadequate potential. The global demographic slowdown notwithstanding, the “population explosion”‐related issues pertaining to food and agriculture will not become irrelevant but will be become increasingly localized.  相似文献   

2.
Attention is given to population and growth and the impact on the environment and resources in China. Policies for managing the environment and instituting population education are also addressed. The first position paper of the National Environmental Protection Agency (NEPAC) on June 2, 1990 is summarized. The population of China was 1.11 billion in 1989. The rate of growth in 1988 was 14.2/1000 in 1988. 91% live in the southeast on 43% of the land. Land area is 9.6 million square miles. 65% can be made arable, and 14% is cultivated. China has 7% of the world's arable land and 20% of the world's population. Population growth has reduced arable land/captia. The impact on forests has been deforestation. 13% of land is currently forested, and timber reserves encompass 9.14 billion cubic meters, or 9 cubic meters/person. The demand for firewood and timber will increase. The impact on grasslands has been overgrazing and desertification at a current rate of 1560 square kilometer/year. The impact on energy resources is a greater demand for coal which will increase and thus increase pollution of the environment. The impact on water resources is greater demand and increased pollution. Water resources are 2700 cubic meters/person or less than the world average. 26.8 billion tons of waste water were industrially discharged out of 36.8 billion tons. 436 of the 532 rivers are polluted. The impact on the environment is a decreased standard of living. NEPAC reported that air pollution was slightly reduced in 4% of the cities in 1988, increased in 4%, and stable in the remaining cities. Water quality improved through the lowering of industrial waste water discharges, but 72% of river segments are still above the standards. Each major river system is discussed. Noise increased, and industrial solid wastes increased. Forest reserve is 9.141 billion cubic meters; the man-made forest has increased. The loss of grasslands is .13 million hectares/year. Cultivated land is 95.72 million hectares, but 100,000 hectares/year are damaged by natural disasters and 6 million are polluted by industrial wastes. 606 nature preserves have been established. In 1989, a complete legal system of environmental protection was established and investment increased.  相似文献   

3.
Population,resources, environment: an uncertain future   总被引:1,自引:0,他引:1  
This issue analyzes the economic and environmental consequences of rapid population growth in developing countries (LDC), the population decline in developed countries, the limits that life on a finite planet impose on economic and demographic expansion and progress, and the proper governmental response to promote the welfare of its current and future citizens. The links between population growth, resource use, and environmental quality are too complex to permit straightforward generalizations about direct causal relationships. However, rapid population growth has increased the number of poor people in LDC, thus contributing to degradation of the environment and the renewable resources of land, water, and nonhuman species on which humans depend. Demands of the rich industrial countries have also generated environmental pressures and have been foremost in consumption of the nonrenewable resources of fossil fuels, metals, and nonmetallic minerals. On the other hand, population and economic growth have also stimulated technological and management changes that help supply and use resources more effectively. Wide variations in the possible ultimate size of world population and accelerating technological change make future interrelationships of population, resources, and the environment uncertain as well as complex. Those interrelationships are mediated largely by government policies. Responsible governments can bring about a sustainable balance in the population/resource/environment equation by adopting population and development policies that experience has shown could reduce future population numbers in LDC below the additional 5 billion indicated in current UN medium projections. This coupled with proven management programs in both LDC and developed countries could brake and reverse the depletion and degradation of natural resources.  相似文献   

4.
The developing countries, with about 3/4 of the world's population, account for less than 1/2 of the production of major food crops. The Third World's per capita food production of 260 kilograms in 1983 was only 1/3 of that in the developed countries. Yet China and India, the most populous countries in the world, have cut fertility rates and moved to food self-sufficiency. An illustration of the food/population dynamic is that although production of food staples in North Africa and the Middle East is projected to expand at about the same rate as that of Asia, about 2.9% annually, owing to a much more rapid rate of population increase, they will achieve only a 0.2% increase in output per person per year, compared with a 1.4% annual growth rate in Asia. In the longer term, higher dietary levels per capita for a world population double that of the present would imply at least a tripling of demand for dietary staples. But more intensive cultivation would place natural resources, many already degraded, under much greater stress. Balancing population, food, and resources for sustained survival is a continual process. The principle cause of hunger and malnutrition is poverty; it is more determinative of nutritional status than aggregate food production.  相似文献   

5.
Issued to mark the Population Reference Bureau's 50th anniversary, this issue updates the story of world population presented in its popular predecessor of 1971, "Man's Population Predicament." Estimated at 1/2 billion in 1650, world population reached about 2 billion in 1930, 4 billion in 1975, and is projected to be about 6 billion in 2000. Most of today's rapid growth is occurring among the 3/4 of the world's peoples living in less developed countries where the post-World War II gap between high birth rates and falling death rates has only recently begun to narrow. This growth, coupled with high consumption in developing countries, is putting tremendous pressures on the Earth's resources, environment, and social fabric. New evidence on Europe's population transition and from China, Indonesia, and Thailand in the 1970s suggests that well-designed family planning programs can speed fertility decline but rapid worldwide attainment of replacement level fertility will also require special development efforts and measures that go beyond family planning. Current projections of the world's ultimate peak population range from 8 billion in the mid 21st century to 11 billion in about 2125, depending on when replacement-level fertility is reached. China's drive for a drastic birth rate reduction and the oil crisis might change fertility behavior more rapidly than most demographers have heretofore thought likely.  相似文献   

6.
The combined population of the ESCAP region is estimated to be growing by an annual increment of 50 million people, and is expected to reach an estimated 2936 million in 1990, when it will constitute 55.4% of the total world population. Continued population growth implies a demand for food, and the majority of the ESCAP countries have to depend on imports to meet their food requirements. Main problems are to improve the capability to produce more food, to adequately provide for health services, housing, and educational facilities for a fast expanding school-age population. With the continuing high rate of population growth the labor force will continue to increase and result in a high rate of unemployment. Population planning must be made an integral part of the over-all plans for socioeconomic development of the entire region.  相似文献   

7.
Although the world's population growth rate will decline to 1.6% by the year 2000, another 2 billion persons will have been added to the world's population by that time. Most of the increase will occur in the world's poorest regions and in countries which also experienced vast growth from 1950-1980. These increases will aggravate the existing problems of rural migration, rapid urbanization, urban poverty, and unemployment and will reduce the impact of development programs. By the year 2000, over 80% of the world's population will live in developing areas. Latin America's proportion of the world's population will increase from 8-10%, Africa's share will increase from 11-13%, and Asia's share, excluding China, will increase from 32-36%. China's share, however, will decline from 28-23%. Within these regions the increases in population will be unevenly distributed. Programs and policies dealing with resource allocation, health, economic development, and job creation will have to be focused on those areas of highest population concentration. If major efforts are not directed toward employment generation, and if employment generation is not tailored to the needs of the labor force in these areas, the resultant increase in poverty will reduce the effectiveness of family planning programs and destroy the gains made in the past to stem population growth.  相似文献   

8.
This Bulletin examines the evidence that the world's fertility has declined in recent years, the factors that appear to have accounted for the decline, and the implications for fertility and population growth rates to the end of the century. On the basis of a compilation of estimates available for all nations of the world, the authors derive estimates which indicate that the world's total fertility rate dropped from 4.6 to 4.1 births per woman between 1968 and 1975, thanks largely to an earlier and more rapid and universal decline in the fertility of less developed countries (LDCs) than had been anticipated. Statistical analysis of available data suggests that the socioeconomic progress made by LDCs in this period was not great enough to account for more than a proportion of the fertility decline and that organized family planning programs were a major contributing factor. The authors' projections, which are compared to similar projections from the World Bank, the United Nations, and the U.S. Bureau of the Census, indicate that, by the year 2000, less than 1/5 of the world's population will be in the "red danger" circle of explosive population growth (2.1% or more annually); most LDCs will be in a phase of fertility decline; and many of them -- along with most now developed countries -- will be at or near replacement level of fertility. The authors warn that "our optimistic prediction is premised upon a big IF -- if (organized) family planning (in LDCs) continues. It remains imperative that all of the developed nations of the world continue their contribution to this program undiminished."  相似文献   

9.
W Hou 《人口研究》1988,(6):32-37
China's population policy has had tremendous effects on the reduction of fertility. The impact of the population policy is manifested in the following aspects. 1) Reducing the size of the total population by 200 million in 17 years. If the population growth rate had remained at its 1970 level of 2.6/1000, the total population would have been 1.28 billion in 1987. 2) The implementation of the population policy accelerated the process of demographic transition. The mortality decline which began in the early 1950s initiated the demographic transition. The Fertility decline began after the birth control policy was implemented and shifted the transition to a low population growth stage even before the socioeconomic conditions which are considered to be the determinants of fertility decline appeared. The fertility decline, in turn, promoted the socioeconomic development of the country. 3) Solving the problem of food; feeding 21.6% of the world's population on 7.1% of the world's farm land is no easy task. The success of population control, no doubt, played an important role in lowering the population growth rate so that the growth of food production could keep pace with the needs of the population. 4) A decline in the dependency ratio is a favorable condition to socioeconomic development. China's dependency ratio of 59.7 is among the lowest in developing countries and is close to the level in developed countries. Therefore, more production output can be used in investment rather than consumption. 5) The fertility decline facilitated a balanced economic growth. The ratio of population growth as compared to the growth of major economic indicators should be considered an important issue in maintaining macroeconomic control. The population policy made it possible for economic growth to surpass population growth.  相似文献   

10.
The world's population growth rate peaked at slightly over 2%/year in the late 1960s and in 1986 is down to 1.7% and falling. Annual numbers added continue to rise because these rates apply to a very large base, 4.9 billion in 1986. According to UN medium variant projections, world population growth will peak at 89 million/year in the late 1990s and then taper off until world population stabilizes in the late decade of the 21st century at about 10.2 billion. Close to 95% of this growth is occurring in less developed countries (LDCs) of Africa, Asia (minus Japan), and Latin America. LDC fertility rates are declining, except in sub-Saharan Africa and parts of Latin America and South Asia, but most have far to go to reach the replacement level of 2.1 births/woman. Fertility is below replacement in virtually all more developed countries. For LDCs, large numbers will be added before stabilization even after attainment of replacement level fertility because of the demographic momentum built into their large and young population bases. This complicates efforts to bridge gaps between living standards in LDCs and industrialized countries. From a new debate about whether rapid population growth deters or stimulates economic growth, a more integrated view has emerged. This view recognizes the complementary relationship between efforts to slow population growth and other development efforts; e.g., to improve health and education, upgrade women's status, increase productivity. Most effective in the increased contraceptive prevalence and fertility declines seen in many LDCs has been the combination of organized programs to increase access to family planning information and supplies with socioeconomic development that enhances the desire for smaller families.  相似文献   

11.
Population and the energy problem   总被引:4,自引:3,他引:4  
When energy is scarce or expensive, people can suffer material deprivation and economic hardship. When it is obtained in ways that fail to minimize environmental and political costs, these too can threaten human wellbeing in fundamental and pervasive ways. The energy problem today combines these syndromes: much of the world's population has too little energy to meet basic human needs; the monetary costs of energy are rising nearly everywhere; the environmental impacts of energy supply are growing and already dominant contributors to local, regional, and global environmental problems (including air pollution, water pollution, ocean pollution, and climate change); and the sociopolitical risks of energy supply (above all the danger of conflict over oil and the links between nuclear energy and nuclear weapons) are growing too. This predicament has many causes, but predominant among them are the nearly 20-fold increase in world energy use since 1850 and the cumulative depletion of the most convenient oil and gas deposits that this growth has entailed, resulting in increasing resort to costlier and/or environmentally more disruptive energy sources. The growth of world population in this period was responsible for 52% of the energy growth, while growth in per capita energy use was responsible for 48% (excluding causal connections between population and energy use per capita). In the United States in the same period, population growth accounted for 66% of the 36-fold increase in energy use. In the late 1980s, population growth was still accounting for a third of energy growth both in the United States and worldwide. Coping with global energy problems will require greatly increased investment in improving the efficiency of energy enduse and in reducing the environmental impacts of contemporary energy technologies, and it will require financing a transition over the next several decades to a set of more sustainable (but probably also more expensive) energy sources. The difficulty of implementing these measures will be greatest by far in the developing countries, not least because of their high rates of population growth and the attendant extra pressures on economic and managerial resources. If efficiency improvements permit delivering the high standard of living to which the world aspires based on a per capita rate of energy use as low as 3 kilowatts—about a quarter of the current U.S. figure—then a world population stabilized at 10 billion people would be using energy at a rate of 30 terawatts, and a population of 14 billion would imply 42 terawatts (compare 13.2 terawatts in 1990). Delivering even the lower figure at tolerable monetary and environmental costs will be difficult; each additional billion people added to the world population will compound these difficulties and increase energy's costs, making everyone poorer.Presented at the Symposium on Population and Scarcity: The Forgotten Dimensions.  相似文献   

12.
The reduction of population growth rates through family planning programs is being attempted in many of the developing nations of the world. This activity lends itself aptly to mathematical modeling. Building from the well-known difference equation model of population growth, a model is constructed which integrates population dynamics, program activities, and resource consumption. The model may be used predictively to assess the outcome of various program activities. Alternatively, it may be used to determine the pattern of activities which yields the greatest reduction in births under the projected resource constraints. A further use of the model is the identification of the parameters to which predictions are most sensitive; such information provides valuable insights to those gathering the input data. The model is here applied to a family planning program currently in progress. An evaluation of the feasibility of that program’s goals is provided, as well as information on limiting resources, data sensitivity, and the most important ages for contraceptive acceptance.  相似文献   

13.
This bulletin examines the narrowing margin between global food production and population growth. Between 1950 and 1971, world grain production nearly doubled and per capita production increased 31%. During the 1970s, gains in output barely kept pace with population growth, consumption/person declined in sub-Saharan Africa and parts of Asia, food prices were volatile, and over 100 food deficit countries came to depend on the exportable surplus of North America, now the only major grain exporting region. The world fish catch levelled off in the early 1970s and beef production, still dependent mainly on grassland grazing, levelled off in the mid-1970s. With little new land left to plow, satisfying increased food demand now depends on sharp increases in yields on existing crop land. Worldwide, this effort is hampered by loss of topsoil and irrigated land, conversion of cropland to nonfarm uses, rising energy costs, inefficient agrarian structures, particularly in the Soviet Union, the falling yield response to chemical fertilizers in agriculturally advanced countries, and the emerging competition between food and agriculturally based energy crops. Green Revolution successes in some developing countries deomonstrate that, given the right inputs, 3rd world farmers can increase crop yields dramatically. Feeding the world's poor also requires more equitable income and food distribution, including a reduction in the proportion of grain and fish consumed indirectly as livestock products by the affluent. Most important in meeting food needs on a finite planet is braking population growth. The author concludes that every effort should be made to stabilize world production at abour 6 billion by 2020, rather than 10.5 billion by 2110, as is now projected by the UN.  相似文献   

14.
Y Lian 《人口研究》1983,(1):17-22
Problems in population, manifested primarily as either "over" or "under" population, are ultimately related to the development of natural resources. Land is the most basic of natural resources. China's land mass is largely mountainous, with 56% of its more than 2000 counties, 1/3 of its population, 40% of its cultivated land and a majority of its forests, situated in mountainous regions. The quality and the distribution of the various kinds of land are complex and uneven. Although China is rich in forests, grazing, and arable land compared to the rest of the world, its 1 billion population makes the land a limited resource. The limitations of the land are also seen in soil erosion, soil that is increasingly turning into sand, and deforestation. Water resources are not considered scarce, yet compared to the rest of the world, it is limited. Its distribution is very uneven, with more water in the east and west, and less in the north and south. In the southwest mountainous border regions, for instance, water is abundant, but the population and arable land there is such that the demand for water is low. Moreover, droughts and heavy precipitation make the annual water supply unpredicatable. The demand for water becomes increasingly greater as agricultural production develops further, the population increases and as the cities continue to expand. living matter as a resource includes all the animal and plant life that is necessary for livelihood, but only forests and grasslands are discussed here. China's forests, if their use is not abused, can serve as a continuous supply for manufactured products. But its distribution is uneven and sparse. Population control will be ineffective if the forests are not replenished and developed. Grasslands are the primary source for animal products. The natural grasslands, found mainly in the north and west, are not as productive as that of other nations due to the nature of China's topography, the vagaries of climate, and deterioration. Energy, the source for fuel, includes such natural resources as coal, petroleum, natural gas, hydraulic, and solar power. China is among the world's richest in energy resources, yet the supply is sometimes insufficient when spread among 1 billion people.  相似文献   

15.
The links between population growth, resource use, and environmental quality are too complex to permit straightforward generalizations about direct causal relationships. Rapid population growth, however, has increased the number of poor people in developing countries, thus contributing to the degradation of the environment and the renewable resources of land, water, and nonhuman species on which humans depend. Demands of the rich industrial countries have also generated environmental pressures and have been foremost in the consumption of the so-called nonrenewable resources: fossil fuels, metals, and minerals. On the other hand, population and economic growth have also stimulated technological and management changes that help supply and use resources more effectively. Wide variations in the possible ultimate size of world population and technological change make future interrelationships of population, resources, and the environment uncertain as well as complex. But those interrelationships are mediated largely by government policies. Responsible governments can bring about a sustainable balance in the population/resource/environment equation by adopting population and development policies that experience has shown could reduce future population numbers in developing countries below the additional five billion indicated in current United Nations medium projections, coupled with proven management programs in both developing and developed countries that could brake and reverse the depletion and degradation of natural resources.This article is adapted from: Robert Repetto, "Population, Resources, Environment; An Uncertain Future,"Population Bulletin, Vol. 42, No. 2 (Washington, D.C.: Population Reference Bureau, 1987).  相似文献   

16.
Petroleum and People   总被引:2,自引:0,他引:2  
The discovery of oil peaked in the 1960s, meaning that the corresponding peak of production is now imminent. The technical evidence is compelling, but the issue is clouded by denial and obfuscation. Peak oil threatens to be a historic discontinuity as the economic growth of the past Century, which was driven by an abundant supply of cheap oil-based energy, gives way to decline. The population of the world, which grew six-fold in parallel with oil, faces decline, probably accompanied by rising migration pressures. Radical new political structures may be needed in a world facing ever deeper resource and environmental constraints.  相似文献   

17.
This article identifies four types of social externalities associated with fertility behavior. Three are shown to be pronatalist in their effects. These three are exemplified by the way theories of economic growth treat fertility and natural resources, the way population growth and economic stress in poor countries are seen by environmental and resource economists, and the way development economists accommodate environmental stress in their analysis of poverty. It is shown that the fourth type of externality, in which children are regarded as an end in themselves, can even provide an invidious link between fertility decisions and the use of the local natural‐resource base among poor rural households in poor countries. The fourth type is used to develop a theory of fertility transitions in the contemporary world; the theory views such transitions as disequilibrium phenomena.  相似文献   

18.
In seeking a solution to its population problem, China, as a developing socialist country, has been making unremitting efforts to develop economy while controlling the rapid growth. The objective is to control rapid population growth so that population growth may be in keeping with socioeconomic development and commensurate with utilization of natural resources and environmental protection. In the past decade, and particularly since 1979, China has made much progress in developing economy and gained remarkable successes in controlling population growth. The natural population growth rate dropped to 1.15% in 1983, from 2.089% in 1973. Living standards have improved with a gradual annual increase of per capita income. All this proves that the policy of promoting family planning to control population growth along with planned economic development is correct. In China family planning is a basic state policy. The government has advocated the practice of "1 couple, 1 child" since 1979. This does not mean that 1 couple could have 1 child only in every case. The government provides guidance for the implementation of family planning programs in the light of specific conditions such as economic developments, cultural background, population structure, and the wishes of the people in different localities. The requirements are more flexible in rural than in urban areas and more so among the people of national minorities than among the people of the Han Nationality. In rural areas, couples who have actual difficulties and want to have 2 children may have a 2nd birth with planned spacing. In carrying out its family planning program, China has consistently adhered to the principle of integrating state guidance with the masses' voluntariness. The government has always emphasized the importance of encouraging the people's own initiatives, through publicity and education, which is the key link in implementing the family planning program.  相似文献   

19.
Food demands for staple grains are expected to almost double over the next 25 years in South Asia, due to population growth and increased standards of living. Trends in the mid-1990s suggest that neither pessimism nor optimism prevails in the region. There is wide diversity among and within countries. Trends suggest that population densities are already the highest in the world, and the amount of arable land is declining. Urban growth has moved onto farm land and farmers have been pushed onto more marginal lands or have become landless. Land intensification has produced mixed results. Cereal production per capita has increased since the 1950s in India, with about 75% of the region's population, but Pakistan's increases were not sustained into the 1980s. Average daily caloric intake per person in the region of 2214 is below the level in Sub-Saharan Africa. In Bangladesh, levels are particularly worrisome at 2037. The environmental impact has not been easily quantified, but experts have suggested that pressure on farm land has contributed to loss of soil fertility and water resource loss. Further intensification of farming is feasible, but difficult and more expensive than in the past. Regardless of production problems and solutions, there is also the very real problem of poor food distribution and lack of purchasing power. Farm management skills must be utilized, if environmental degradation is to be avoided. There is the added unknown of what climate changes will occur and how agricultural production will be affected. The policy implications are that increased food production must be made a political priority. Policies must support agricultural research into improved technologies and support distribution of technological advances to a wider number of farmers. Rural infrastructures such as roads, market outlets, and credit agencies must be established. Policies must be removed that disadvantage farmers, such as inappropriate subsidies for irrigation water, inadequate tenure agreements, and price setting. Slowing population growth provides time to adjust to expanding production and saving the environment.  相似文献   

20.
This paper examines linkages between the demographic changes taking place in Zaire, particularly overall population growth and rapid urbanization, changes in agricultural practices, and related environmental degradation. Pressures to feed Zaire's rapidly increasing urban population, which fall on a rural population that has been growing relatively slowly in recent years, as well as population growth and increased population density in certain areas of the country, have resulted in changes in agricultural practices that are described in the paper. These changes in turn are leading to declining soil fertility, deforestation, and degradation of the natural resource base. Given present technology and the state of Zaire's economy, the changes in agricultural practices that have emerged in response to population growth, increased population density, and growth in demand for food production do not appear to be sustainable in the long run.  相似文献   

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