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1.
In 1950 Latin America's population of 165 million was on a par with the 166 million of North America. 2 decades of growth at nearly 3% a year pushed the total to 405 million in 1985, vs. 264 million in North America. Despite substantial fertility declines since the 1960s, continued growth is ensured by the demographic momentum built into the region's large and youthful population bases. UN medium projections put the 2025 total at 779 million, compared to 345 million in North America. This Bulletin examines the main demographic changes in Latin America since World War II and their links to economic and social changes in the region as well as their implications for international and social relations. The post World War II population surge was accompanied by massive rural-ruban and international migration, rapid urbanization, large labor shifts out of agriculture into industry and services, increased education for both men and women, and higher labor force participation for females. The rural exodus was spurred by extreme land tenure inequalities and the urban bias of postwar industrialization. The labor-saving bias of this industrialization forced exploding city populations to turn to the informal sector for jobs. Population pressures on city services and housing as well as jobs have been further exacerbated by overconcentration in a few large cities and economic downturns of the 1980s. Recent fertility declines seem to be the result of both increased access to family planning and the economic and social pressures posed by the gap between young adults' aspirations and their ability to realize them. Population and economic pressures could induce faster fertility declines than now projected but in the short run are likely to mean more employment problems, continued rapid urban growth, and even larger international immigration flows within the hemisphere, particularly to the US.  相似文献   

2.
Because of urgent concerns to protect tropical forests in Latin America, social science research on them has been generally ‘forest-centred.’ This forest-centred approach considers the people who inhabit the frontier as agents of land use change and forest conversion focusing on how their actions affect forest cover. Welfare indicators for forest frontier populations (income, education, health, access to basic services) are addressed only incidentally in terms of how they influence land use. ‘People’ centred research, which asks questions from the perspective of human welfare such as, ‘Are frontier settlers better off than they were before?’ or ‘What kind of socio-economic impacts does frontier life have on the people who live there?” and “How can their lives be improved?,” has been less common. As a result, we know much about the impacts, especially adverse impacts, which settler activity on the frontier has on forest cover but little about the impacts settlement has on settlers, themselves. This paper attempts to shift discussion towards these kinds of questions and a more people centred approach by reviewing existing research that directly addresses the welfare of settlers in tropical forest frontiers in Latin America. We also review research that touches on settler welfare by considering the concept of ‘sustainability’ on the forest frontier and stakes out a comprise position between ‘forest’ and ‘people’ centred questions or concerns. Settler welfare is defined primarily in economic terms. Household income, wealth, and agricultural productivity are interpreted a proxies for welfare in most cases. We also consider welfare in terms of access to basic services (health and education) and living conditions. We particularly consider how settler welfare indicators may change over time on the frontier. Tropical forests, defined as tropical, moist, broadleaf forests, are the main ecological setting of interest. These forests are generally the largest unoccupied areas in many Latin American countries and are thus, also the main ‘agricultural frontier’ or areas of new settlement by small farmers.  相似文献   

3.
Despite an abundant literature exploring the relationship between population growth and forest cover change, comparatively little research has examined the forest cover impacts of family planning use—a key determinant of population growth rates in many developing countries. Using data from a panel survey of farms in the Northern Ecuadorian Amazon, this paper explores whether family planning use affects changes in forest cover. After controlling for household life cycle effects, family planning use among female heads of farm households did not have an independent effect on deforestation, reforestation, or net forest loss between 1990 and 2008. Rather, shorter-term drivers of forest change tend to be associated with household life cycles and shifts in production and consumption. However, family planning will continue to improve development and health outcomes for women by reducing unwanted fertility and may offer longer-term environmental benefits.  相似文献   

4.
This paper seeks to broaden the application of demographyto environmental studies by complementing existing macro-level approaches, which feature aggregate populations, with a micro-level approach that highlights household life cycles. I take up the case of small farm households in the Brazilian Amazon to present a theoretical framework that identifies demographic characteristics which dispose families to engage in different forms of land use as household age structures change. Empirical models show that net of theeffects of farmer background, neighborhood context, institutional context, and off-farm incomes, demographic variables indicative of the household life cycle exert significant effects on the prominence of land uses with distinct environmental ramifications. The findings not only reveal micro-level demographic factors which affect Amazon land cover, they yield implications forfuture changes in rainforest landscapes in northern Brazil, and suggest household life cycle models as an avenue for further demographic research on environmental change in Latin America and other contexts.  相似文献   

5.
Demographic interest in population and environment has grown in recent decades. One of the most prominent research areas in this tradition addresses the impact of population on land use and land cover change. Building on this tradition, we examine the effects of household demographic composition on land use and land cover on small farms in two study areas in the Brazilian Amazon. Fixed effects regression models of used area and forested area show few consistent effects of changes in household demography on land use and land cover change. Effects are inconsistent with the household life cycle model that currently dominates the literature on household demographic effects in frontiers. Changes in the number of children and women, particularly young women, have the most significant effects on land use and land cover change. We conclude by arguing that households strategically access cash for investment in agriculture and that specific strategies are determined by economic and institutional context.
Leah K. VanWeyEmail:
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6.
A study by historical comparison of the fertility trends related to mortality levels is made between Latin America and Europe. The purpose of such study is to show why Latin America did not repeat the European mortality-fertility pattern during 1930–1960. Differences between the two areas are established, and an explanation is given about the particular Latin America mortality-fertility model. The effects of such a Latin America trend are pointed out, principally in relation to population growth, city growth and labor force. Hypothetical Latin American populations are calculated under the assumption that the area has repeated the European pattern. A comparison between these hypothetical populations with the actual ones shows how different the situation of the area has actually been. Nevertheless, an analysis of the necessary fertility changes in order to reproduce the European model shows that it was impossible for Latin America to repeat the European mortality-fertility experience during 1930–1960.  相似文献   

7.
Property Size and Land Cover Change in the Brazilian Amazon   总被引:1,自引:0,他引:1  
This paper considers the size of a farmer’s property as a key variable influencing land cover and land cover change in rural areas of developing countries. Data from 126 rural familial properties in the region around the city of Santarém, Pará, in the Brazilian Amazon, indicate that property size is important for understanding the trajectories of land cover change. Past research has focused on the distinction between small family farms and large capitalized farms, arguing that family farmers have a higher deforestation intensity, or on estimating the strength of the effect of property size relative to economic or demographic factors. This paper shows that larger familial properties are able both to retain a larger area in forest and to have long enough cycles of use and fallow to allow previously used land to become forested again. Based on these analyses and discussion, we argue that land use and land cover research must consider property size as an organizing principle in order to better comprehend the reciprocal relationship between population and environment in frontier areas of the Brazilian Amazon and other rural landscapes.  相似文献   

8.
The dramatic changes in the earth’s landscape have prompted increased interest in the links between population, land use, and land cover. Previous research emphasized the notion of population pressure (population pressure increases demands on natural resources causing changes in land use), overlooking the potentially important effects of changes in land use on humans. Using multiple data sets from the Chitwan Valley Family Study in Nepal, we test competing hypotheses about the impact of land use on first birth timing. We argue that while agricultural land should encourage early childbearing, land area devoted to public infrastructure should discourage it. The results show that individuals from neighborhoods with larger proportions of land under agriculture experienced first birth at rates higher than those from neighborhoods with smaller proportions. On the other hand, individuals from neighborhoods with larger proportions of land under public infrastructure experienced first birth at rates lower than those from neighborhoods with smaller proportions. However, the effects of public infrastructure are not as strong as the land area devoted to agriculture.
Dirgha J. GhimireEmail:
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9.
The reasons for the rapid growth of population that occurred during the early-middle period of the Qing dynasty in China are examined. Factors considered include Kan Hsi's tax reforms, the expansion of Chinese borders, increased food production, and socioeconomic changes brought about through contact with the West during the reign of Dao Guang. The consequences of the rapid growth of population for land use and food distribution are also considered.  相似文献   

10.
Water resources are the root of life and development in arid areas like the Xinjiang Autonomous Region of China. In the Tarim Basin in Xinjiang, one of the driest places in the world, melting glaciers are the exclusive water source. Population growth, in particular in-migration, has greatly changed the ecological conditions of the Tarim River Basin in the past 2,500 years. Our research aims to study the interactions between population growth and changes in water and land resources, crossing the boundaries of the different reaches in the Tarim River Basin over the past 50 years. Time series data on population changes and economic development, water volume and quality, land use and land cover changes, and prevalence of morbidity relevant to water quality are collected to study the relationship between these factors. Adopting a statistical analysis and systems dynamics approach, we quantify the effect of population growth on water use and land degradation. 1This paper results from the research project “Population changes and land degradation in Xinjiang of China,” funded by the Wellcome Trust Foundation (grant no. 065867). The authors appreciate the comments from the anonymous reviewers, and wish to extend thanks to the Asian MetaCentre for Population and Sustainable Development Analysis, and to Warren Sanderson, Wolfgang Lutz, Brenda Yeoh, Vipan Prachuabmoh, Min Weifang, Zheng Xiaoying, Brian O’Neill, Steve Hamburg, Laura Sadovnikoff, Verene Koh, and Sam Balakrishnan, for their invaluable support and help.  相似文献   

11.
This paper estimates village-level models of the effects of population variables on the area devoted to upland crop production in Nang Rong district, Thailand. The expansion of upland crops is part of the growth of market agriculture in Nang Rong, and a correlate of deforestation in this setting, The results show that population density (measured as density of village settlement) negatively affects area in upland crops while population growth has a positive effect. Changes in land use associated with population change appear to radiate outward from nuclear village centers. As cash economies are established in rural settings, household formation requires a source of income as well as a subsistence stake. Growth in the population of households is a stronger predictor of the area in upland crops than growth in the number of persons.  相似文献   

12.
Globalizing processes of industrialization and Westernization are creating a retreat from diversity in human experience. The paper discusses whether population trends are reinforcing this process and draws on findings about growth rates, the family and urbanization in Western countries. East and Southeast Asia and Latin America. The extent to which counterbalancing forces, including cultural resilience, are curbing homogenization is also examined.  相似文献   

13.
This article assesses the relationship between demographic change and structural adjustments in agriculture. A number of demographic and economic analyses have posited an inverse relationship between post-1950 exurban population growth and agricultural viability, especially in the Northeast Region of the USA. To test this hypothesis, a multivariate model of percent change in county land in farms over the period 1950–1987 is estimated, and the findings only partially support the population hypothesis. Estimation results indicate that the effect of core metropolitan status is significant, but that the effects of rural population change, rural nonfarm population change, and county population deconcentration are not. The analysis demonstrates that maintenance of land in farm use largely depends upon economic forces that are national and regional in scope, and almost exclusively outside the purview of state and local farmland protection programs.  相似文献   

14.
Forest conversion for agriculture expansion is the most salient signature of human occupation of the earth's land surface. Although population growth and deforestation are significantly associated at the global and regional scales, evidence for population links to deforestation at micro-scales—where people are actually clearing forests—is scant. Much of the planet's forest elimination is proceeding along tropical agricultural frontiers. This article examines the evolution of thought on population–environment theories relevant to deforestation in tropical agricultural frontiers. Four primary ways by which population dynamics interact with frontier forest conversion are examined: population density, fertility, and household demographic composition, and in-migration.  相似文献   

15.
Many influential analyses of West Africa take it for granted that ‘original’ forest cover has progressively been converted and savannized during the twentieth century by growing populations. By testing these assumptions against historical evidence, exemplified for Ghana and Ivory Coast, this article shows that these neo‐Malthusian deforestation narratives badly misrepresent people–forest relationships. They obscure important nonlinear dynamics, as well as widespread anthropogenic forest expansion and landscape enrichment. These processes are better captured, in broad terms, by a neo‐Boserupian perspective on population–forest dynamics. However, comprehending variations in locale‐specific trajectories of change requires fuller appreciation of social differences in environmental and resource values, of how diverse institutions shape resource access and control, and of ecological variability and path dependency in how landscapes respond to use. The second half of the article présents and illustrates such a “landscape structuretion” perspective through case studies from the forest–savanna transition zones of Ghana and Guinea.  相似文献   

16.
The need to combine spatial data representing sociodemographic information across incompatible spatial units is a common problem for demographers. A particular concern is computing small area trends when aggregation zone boundaries change during the trend interval. To that end, this study provides an example of dasymetric areal interpolation using the pre-classified land cover data available through the US Geological Survey’s National Land Cover Dataset (NLCD) program. Areal interpolation of population estimates is preferable to traditional reaggregation techniques, and the use of land cover data as a weighting factor in interpolated estimation has been shown in earlier studies to be highly accurate. In this study, the NLCD data set performs well and, because it requires no classification, it compares favorably with other land cover data sets for areal interpolation when considered on the basis of accuracy, precision and ease of use.  相似文献   

17.
Policies on population,land use,and environment in Rwanda   总被引:1,自引:1,他引:0  
The paper first describes the interactions between population growth, land use, and environment in Rwanda, a small, densely populated landlocked nation in the East-African Great Lakes region. These interactions are modelled using a conceptual framework applied to the neighboring Kivu region in Zaire, but adapted to the Rwandan case study. Second, the paper contends that the emphasis put on increasing agricultural production, mostly through the use of marginal land, as well as the lack of a timely implementation of a family planning program and a national population policy, have led to a worsening of the interactions between population growth, land use, and environment. In an attempt to demonstrate this hypothesis, demography-driven projection scenarios are applied to the agricultural colonization and intensification processes.  相似文献   

18.
An Optimum Population for North and Latin America   总被引:1,自引:0,他引:1  
The population of North America, which now stands at nearly 300 million people, is projected to double in about 60 years, while the population of nearly 500 million people in South America is projected to double in less than 40 years. Both of these populations obtain more than 99% of their food from the land, and this percentage will increase as these populations grow. Maintaining fertile and ample land is critical if these large populations are to be fed. Soil degradation by soil erosion is a serious problem on both continents. In addition, agricultural land is being lost to urbanization and highways because of rapid population growth. Nearly a half hectare of land is needed for urbanization for each person added to the North American population; this is already causing serious problems with agriculture in some states in the United States. The land resources that are critical for food production will be especially so if the populations of both continents double to nearly 2 billion. Land resources will also be critical when both continents deplete their fossil fuels in less than 100 years and have to turn to renewable energy sources. With about 2 billion people, there will be serious shortages of food, water, and energy resources and the standard of living will significantly decline. Our assessment suggests that for a relatively high standard of living in North and South America each continent should have no more than about 200 million people, or a total of 400 million.  相似文献   

19.
Population growth,farmland, and the long-run standard of living   总被引:1,自引:0,他引:1  
This paper studies the natural-resources element in the theory of population growth over the very long run. In the context of the stock of land and Malthusian crises in earlier times, the model shows how resources have become more available rather than more scarce, even as population and income have increased.The paper sketches a mechanism which, added to the Malthusian system, leads to entirely different conclusions than does the Malthusian system. Using the illustration of food and land, change in knowledge and hence in the stock of resources is made a function of the stock of knowledge and the price of resources. The speed of adjustment depends on the economic and social climate for the development of new knowledge. Population growth first raises food and land prices, which then stimulate the creation of new resources, eventually leading to less scarcity of resources and lower prices than originally prevailed.That is, population growth creates new problems which in the short run constitute additional burdens which, in the longer run, lead to new developments that leave people better off than if the problems had never arisen.This paper benefitted from being presented in earlier draft at a Population Association of America meeting, to the Economic History workshop at the University of Illinois, and to a seminar of the International Union for the Scientific Study of Population in New Delhi. We appreciate valuable comments on earlier drafts from Stanley Engerman, E. L. Jones, William McNeill, and two anonymous referees. Gunter Steinmann acknowledges financial support from the Volkswagen Foundation and a travel grant from Fulbright Commission.  相似文献   

20.
L Yang 《人口研究》1982,(5):48-49
The population devoted to agriculture constitutes more than 80% of China's total population. This high percentage is not very common in today's world. In the last 30 years, the population devoted to agriculture has increased by 81.9%, but the area of arable land has decreased in the same period of time. This situation has created problems, such as a surplus of agricultural labor, an imbalance between the agricultural population growth and agricultural means of production, a serious contradiction between the agricultural population growth and mechanization of agriculture, an imbalance between the agricultural population growth and means of livelihood, and the current low standard of living for populations engaged in agricultural work. In order to solve the problems of overpopulation, various measures must be taken in different places. The economic structure of agriculture is to be reasonably arranged, and various operations in agriculture are to be carried out. In addition to the production of main agricultural crops, forestry, animal husbandry, the fishing industry, and family supplementary income are to be developed in order to provide more job opportunities. Communes and production teams should emphasize labor intensive plans for more profit with less investment. Agriculture should focus on intensive farming in order to increase productivity. Arable land can be expanded with reclamation projects, and water and soil conservation is necessary. The surplus agricultural population should be utilized for productive activities.  相似文献   

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