Population,immigration, and air quality in the USA: a spatial panel study

Population and Environment - The role of population size in environmental degradation is a source of both political and academic debate, with the role of immigrant population being particularly...     

Population,resources, environment: an uncertain future

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.     

Environmental Effects on Family Size Preferences and Subsequent Reproductive Behavior in Nepal

This study investigates the relationship between environmental degradation and men and womens family size preferences and subsequent reproductive behaviors in Nepal. We draw on unique environmental data at the local level, household and individual-level survey data and individuals reproductive behavior over a 3 year time period in Western Chitwan Valley, Nepal. Results from Ordinary Least Squares (OLS) and logistic regression models show that poorer environmental quality and greater reliance on publicly owned natural resources are associated with higher family size preferences and higher rates of pregnancy. The analyses provide support for the vicious circle argument that environmental degradation can lead to rising population growth via positive effects on fertility. As environmental conditions decline and when households rely on public lands for natural resources, men and women desire larger family sizes and women are more likely to get pregnant in the near future.     

Renewable resources and population growth: Past experiences and future prospects

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).     

The future of world population

Analysis of future population trends reveals a regional pattern of continued growth, dependent upon basic assumptions about demographic factors and the priority given to human rights, socioeconomic development, and global interdependence. Developing countries will account for 85-87% of world population growth, and the most rapid increase will occur in Africa. The optimum size of population remains debatable. Ecologist argue for a reduction to 1-2 billion people in order to be in balance with nature and maintain a high quality of life. A rapid, but plausible, fertility decline would result in a population of 10 billion by 2070. The lowest feasible UN projection is 8 billion. A 1-2 billion world population would not be feasible without drastic mortality increases and fertility declines. Population control is a highly charged and complex issue; feminists are not about to place responsibility for environmental degradation on women's excess fertility. The spirit of the UN Universal Declaration of Human Rights is that women have the right to determine family size with personal integrity and freedom rather than suffer coercion for the rights of society. Family planning is a necessary ingredient for achieving the goal of desired family size. The quality of life may be undermined by upholding human rights, without recognition of the context of socioeconomic development and global interdependencies. Global economic conditions, political crises, and environmental degradation can undermine even the best national development efforts. The most difficult task ahead is addressing priorities and forming a consensus. Human rights, socioeconomic conditions, and global interdependencies must be satisfied in a mutually beneficial way. When national and global goals conflict, a compromise must be reached. There are many unknowns. The challenge is to "identify a set of policies that will stabilize world climatic conditions, promote economic development, enhance the quality of life, and respect human rights." Investment in human capital, such as education and health, will help women to avoid unwanted pregnancies. Improving the status of women is key to socioeconomic development, human rights, and global interdependencies.     

人口变动对干旱区生态环境的影响及作用机制——以新疆玛纳斯河流域为例

本文以建国后新疆开垦的最大人工绿洲——玛纳斯河流域为例．分析了干旱区人口变动与生态环境演变之间的主要作用机制以及存在的主要矛盾。认为人口数量增长引起的资源环境压力。是导致干旱区环境退化的主要人为诱因,不均匀的人口空间分布模式则加剧了这种资源环境压力．而人口的素质状况则决定了人口资源环境压力下最终的环境演化方向。     

Population, Nomadic Pastoralism and the Environment in the Mongolian Plateau

The purpose of this paper is to examine the relationship between population, economic activity and the environment in the Mongolian Plateau. This analysis provides a valuable case study for several reasons. First, it elucidates a specific ecosystem—the steppe—that has not received much attention in the literature and a traditional economic activity consistent with such environment: nomadic pastoralism. Second, the Mongolian Plateau is shared by two entities, with two different economic and social organisation: the Republic of Mongolia and the Inner Mongolia Autonomous Region of the People's Republic of China. Third, these two entities have also experienced two different population dynamics that have resulted in different population densities and population pressure on natural resources. Fourth, environmental degradation does not seem to be a problem in the Republic of Mongolia, while in Inner Mongolia the quantity and quality of the grasslands are in decline.The argument discussed here is that the difference in resource depletion and environmental degradation between the two regions is mainly the result of different population dynamics, which has resulted in different human and animal population densities.     

Age structure and economic policy: The case of saving and growth

The age structure of the population affects aggregate saving, which affects growth through investment. Growth in turn is influenced by other age structure effects and feeds back into aggregate saving by well known life cycle mechanisms. Some of these feedbacks are generally ignored in empirical work. Especially the age structure effect on macroeconomic variables is a commonly overlooked, yet easily accessible factor useful for prediction, policy evaluation and design. The connection between age structure, savings and growth in the OECD from 1950 to 1990 illustrates how policy analysis that ignores the macroeconomic effects and feedbacks from age structure changes is liable to lead to faulty and potentially costly conclusions about policy issues.     

Population growth,changing agricultural practices,and environmental degradation in Zaire

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.     

How and why journalists avoid the population-environment connection

Recent surveys show that Americans are less concerned about population than they were 25 years ago, and they are not connecting environmental degradation to population growth. News coverage is a significant variable affecting public opinion, and how reporters frame a problem frequently signals what is causing the problem. Using a random sample of 150 stories about urban sprawl, endangered species and water shortages, Part I of this study shows that only about one story in 10 framed population growth as a source of the problem. Further, only one story in the entire sample mentioned population stability among the realm of possible solutions. Part II presents the results of interviews with 25 journalists whose stories on local environmental problems omitted the causal role of population growth. It shows that journalists are aware of the controversial nature of the population issue, and prefer to avoid it if possible. Most interviewees said that a national phenomenon like population growth was beyond the scope of what they could write as local reporters.     

环境退化地区家庭人口对土地利用的影响研究——以中国西北毛乌素沙地为例

微观层面模型对于区分不同的人口群体以更好地明确环境退化的责任主体及其原因具有重要价值,对不同的土地利用方式进行经济区分是联接家庭人口特征与土地覆盖结果的重要手段。基于扩展的恰亚诺夫理论框架,文章利用2007—2008年两次调查所获293个农户样本数据,采用OLS和logit多变量模型实证分析毛乌素沙地家庭人口和其他因素对土地利用的影响。研究结果表明:(1)家庭人口因素对毛乌素沙地农户的土地利用产生重要影响;(2)毛乌素沙地主要土地利用的环境影响也遵循家庭生命周期的过程;(3)毛乌素沙地农户在减少有助于土壤修复利用活动的同时面临上升的退化风险。     

Family planning and reproductive health: the link to environmental preservation

This paper seeks to refocus the attention of environmentalists on the importance of population trends to environmental sustainability and identifies prevention of unintended pregnancy as potential common ground for environmentalists and family planning advocates. The health and other welfare benefits of preventing unintended pregnancy are felt most keenly by individual women, men, and their families. At the same time, however, preventing unwanted pregnancies usually results in smaller family size, an important factor in slowing population growth and, as a result, a source of broader benefits—including environmental benefits—to society.     

人口、消费、技术模式变化对我国海洋渔业生产影响的实证研究——以浙江舟山渔场为例

本文以舟山为例 ,在以往研究的基础上 ,修正了过去所建构的人口、消费、生产和资源的系统模拟分析框架 ,并利用系统动力学的方法 ,选择了投资规模、技术进步等变量进行了系统仿真模拟分析。研究结果表明 ,在渔业资源限定条件下 ,投资规模对渔业生产的影响是有限的 ;而技术进步的影响则是十分显著的 ;同时 ,劳动力资源短缺也将会显现出来     

Ecosystem resilience, specialized adaptation and population decline: A modern Malthusian theory

The purpose of this article is to construct a theoretical framework characterizing the interactions among economic development, ecosystem equilibrium and possible population decline, and to discuss the population dynamics in the very long run. In our framework, economic activities bridge population and environment. On the one hand, human beings reform the environment through economic activities; on the other hand, economic activities decrease environmental resilience and increase the possibility of an environmental change in a discontinuous and irreversible pattern, as described in Arrow et al. (1995). Furthermore, a highly developed economy also causes over-specialization of human adaptation, which tends to exaggerate the impact of an environmental change on human population size. Received: 19 January 1999/Accepted: 3 July 1999     

Land tenure, population, and long-run growth

This paper brings together the development literature on land tenure with current research on population and long-run growth. Landowners make a decision between fixed rent, fixed wage, and sharecropping contracts to hire tenants to operate their land. The choice of tenure contract affects the share of output going to tenants, and within a simple unified growth model, this affects the relative price of food and therefore fertility. Fixed wage contracts elicit the lowest fertility rate and fixed rent contracts the highest, with sharecropping as an intermediate case. The implications of this for long-run growth depend on the assumptions one makes about scale effects in the aggregate economy. With increasing returns to scale, as in several models of innovation, fixed rent contracts imply higher growth through a market size effect. Without such increasing returns, though, fixed rent contracts reduce output per capita through a depressing effect on accumulation.     

Identifying Synergies and Complementarities Between MDGs: Results from Cluster Analysis

The MDGs are interlinked: acceleration in one goal is likely to speed up progress in others. Nevertheless, these synergies are not always visible, and may differ across countries. Using bivariate cluster analysis, this paper investigates whether distinct groups of developing countries can be identified, using statistical methods, on the basis of the correlation of changes in main MDG indicators over the 1990–2008 period. Identified groups include: (1) “good performers”, characterized by strong positive synergies in MDGs indicators; (2) “poor performers”, where there are synergies in poor progress towards the MDGs and (3) “partial performers” countries where progress in one MDG went along with regress or stagnation in another. We then study the determinants of cluster membership. While growth in GDP per capita is, unsurprisingly, best able to distinguish between “good” and “poor” performers, a poor institutional framework and deteriorations in the income distribution is a notable correlate of partial progress, thus apparently undermining synergies in reaching the MDGs. In light of the current discussions about the post-MDG system, our results suggest that synergies between MDG progress can be achieved but they cannot be taken for granted. Improving institutional performance and reducing inequality appear particularly important drivers of promoting such synergies.     

Negative population growth: how to go about it? (Letter to the editor)

It proves an interesting exercise to try to determine the effects of a national policy of government control developed on the basis of the need to conserve scarce resources, lessen environmental pollution, and to reduce the U.S. population to 1/2 of the 1970 figures within 100 years without increasing the risks of death. Let it additionally be assumed that in order to minimize the required reduction of fertility that there be no net migration. At the end of the reduction process, the stationary state in stable equilibrium might hopefully be achieved. If these are the goals, the process would include 1) reduction of the annual stream of births immediately to the number that would ultimately be required to sustain a population 1/2 as large as the present number and 2) smooth decline of the totals but with constituent age groups shifting drastically as the sharply reduced stream of births spreads upward through the span of life, with those 65 years and older making up 12% of the population. To obtain a fixed annual stream of births from sharply changing numbers of women of childbearing age would require rapid and drastic changes in the rates of childbearing. The same reduced population could be obtained from a system involving less drastic changes in the age composition, but these means would not be positive ones for older individuals. Both fertility and age distribution could move more smoothly if the mortality risks increased or with considerable emigration of the aged. Other means of reducing the population to 1/2 the present size within 100 years would create even more turbulence in the age distribution and rates of childbearing than those just discussed.     

Examining the Impact of Demographic Factors on Air Pollution

This study adds to the emerging literature examining empirically the link between population size, other demographic factors and pollution. We contribute by using more reliable estimation techniques and examine two air pollutants. By considering sulfur dioxide, we become the first study to explicitly examine the impact of demographic factors on a pollutant other than carbon dioxide at the cross-national level. We also take into account the urbanization rate and the average household size neglected by many prior cross-national econometric studies. For carbon dioxide emissions we find evidence that population increases are matched by proportional increases in emissions while a higher urbanization rate and lower average household size increase emissions. For sulfur dioxide emissions, we find a U-shaped relationship, with the population-emissions elasticity rising at higher population levels. Urbanization and average household size are not found to be significant determinants of sulfur dioxide emissions. For both pollutants, our results suggest that an increasing share of global emissions will be accounted for by developing countries. Implications for the environmental Kuznets curve literature are described and directions for further work identified.     

Long-term effects of family planning and other determinants of fertility on population and environment: agent-based modeling evidence from Wolong Nature Reserve,China

The practice of family planning has a long history, but its environmental implications have not often been considered. Using data from Wolong Nature Reserve for the conservation of the world-famous giant pandas in China, we employ a spatially explicit agent-based model to simulate how family-planning and other fertility-related decisions may affect human population, household number, and panda habitat over time. Simulation results indicate that (1) population size has the shortest time lag in response to changes in family-planning decisions, and panda habitat has the longest time lag; (2) the amount of panda habitat is more sensitive to factors affecting number of households than those affecting population size; (3) although not large in quantity nor changing landscape fragmentation substantially, the associated changes in habitat are in good areas for the panda. This study offers a novel approach to studying long-term demographic and environmental effects of family-planning and fertility-related decisions across space.     

A developing countries' perspective on population,environment, and development

The subject of this paper is the political behavior of developing states (the South) on issues of population, environment and development. It attempts to understand why the South is so weary of international population policy in the name of the environment. It argues that the South's response is shaped by five inter-related concerns about responsibility, efficiency, efficacy, additionality, and sovereignty. That is, the developing countries, (a) do not want their population growth to be held responsible for global environmental degradation, (b) argue that a more efficient solution to the environmental crisis is consumption control in the North, (c) believe that development remains a necessary condition for efficacious population control, (d) are weary of the population priorities of the North distracting international funds from other developmental goals of the South, and (e) are unprepared to accept any global population norms which challenge their fundamental political, cultural or religious sovereignty. It is maintained that these concerns have historically guided the positions of the South and remain valid and relevant today. Although, over the last two decades of North-South debate on the subject the nuances within these concerns have evolved, the concerns themselves remain valid and were apparent again at the 1994 International Conference on Population and Development. Finally, it is proposed that although a grand North-South bargain around population-environment-development issues remains unlikely, both sides can gain much from trying to understand - even where they do not agree with - the other's concerns. The purpose of this study is not as much to defend the South's position, as to present it and the rationale behind it.