Environmental change and out-migration: evidence from Nepal

Scholars and activists have hypothesized a connection between environmental change and out-migration. In this paper, we test this hypothesis using data from Nepal. We operationalize environmental change in terms of declining land cover, rising times required to gather organic inputs, increasing population density, and perceived declines in agricultural productivity. In general, environmental change is more strongly related to short- than long-distance moves. Holding constant the effects of other social and economic variables, we find that local moves are predicted by perceived declines in productivity, declining land cover, and increasing time required to gather firewood. Long-distance moves are predicted by perceived declines in productivity, but the effect is weaker than in the model of short-distance mobility. We also show that effects of environmental change vary by gender and ethnicity, with women being more affected by changes in the time required to gather fodder and men by changes in the time to gather firewood, and high-caste Hindus generally being less affect than others by environmental change.     

Natural resource collection and desired family size: a longitudinal test of environment-population theories

Theories relating the changing environment to human fertility predict that declining natural resources may actually increase the demand for children. Unfortunately, most previous empirical studies have been limited to cross-sectional designs that limit our ability to understand links between processes that change over time. We take advantage of longitudinal measurement spanning more than a decade of change in the natural environment, household agricultural behaviors, and individual fertility preferences to reexamine this question. Using fixed effect models, we find that women experiencing increasing time required to collect firewood to heat and cook or fodder to feed animals (the dominant needs for natural resources in this setting) increased their desired family size, even as many other macro-level changes have reduced desired family size. In contrast to previous, cross-sectional studies, we find no evidence of such a relationship for men. Our findings regarding time spent collecting firewood are also new. These results support the “vicious circle” perspective and economic theories of fertility pointing to the value of children for household labor. This feedback from natural resource constraint to increased fertility is an important mechanism for understanding long-term environmental change.     

Environmental security and labor migration in Nepal

Do changes in environmental security that result from declining access to forest resources shape labor migration in a context where household production and consumption are intimately dependent on natural resources? Using 1996 household data from the Chitwan Valley of Nepal, we examined if a decrease in access to firewood increased the likelihood of migration of individuals for work. The results of multinomial logistic regression showed that, environmental insecurity was a significant predictor for migration regardless of destination, domestic or international. Labor requirements for household maintenance also played an important role in the decision to migrate. Management of forest resources and poverty alleviation by providing firewood substitutes and economic opportunities at the local level is likely to change the labor migration flow, which could be an important issue for future research.     

Land and leña: linking transnational migration, natural resources, and the environment in Guatemala

This article examines the relationships between international migration, natural resources, and the environment. Rather than looking at environmental change as a cause of population movements, the article reveals how migration affects the environment in sending countries. Empirically, we rely on a case study in Guatemala. Although migrants and cash remittances make significant contributions to Guatemala’s changing economy, little is known about the relationships between migration and the environment in this Central American country—a country, which continues to have a large rural population and that relies heavily on its natural resources. Drawing on ethnographic research and household surveys in a Maya community, we reveal how migrants and their earnings, as well as their ideas, behavior and attitudes, affect land use, land cover, and firewood use. We reveal, for example, how in addition to investments in land for home building and pick-up trucks to help improve agricultural production, some migrant households purchase more land and often dedicate it to the cultivation of vegetable crops for local and foreign markets. Cultural practices and beliefs directly linked to land and the environment, particularly maize cultivation, also alter due to migration processes. And, despite the ability of migrant households to transition to more efficient fuels like liquid propane gas (LPG), we show how they continue to use firewood. In all, the study contributes important insights into the environmental implications of migration.     

Population control and environment protection]

Although many factors cause environmental pollution and damage, the most important and basic factor is a rapidly increasing population. Therefore, a balanced development of population and environment is essential. The pressure a rapidly increasing populaton exerts on the environment has many aspects. The pressure of population on land resources results in increased land use and increased insecticide use due to increased insect tolerance leading to decreased productivity of cultivated land, increased desert formation, and decreased food supply. Population pressure on forest resources leads to land erosion; one of the major causes of the 1981 flood in Sichuan was attributed to excessive logging activities. Demand for fuels (firewood, straws, animal manures) by an increasing population leads to decrease in natural fertilizers, decreased food production, and energy shortage in rural areas. Population pressure on cities leads to air, water, noise and other environmental pollution as well as decrease in housing facilities and in green vegetation. Problems resulting from population pressures on industrial development include industrial and environmental pollution and unemployment. Population increases and accompanying industrial activities affect the weather which in turn affects the quality of agriculture, forests, and lakes. Thus, if unchecked, atmospheric carbon dioxide level would double by the middle of the next century, which would lead to increase in atmospheric temperature with disastrous consequences. Therefore, a well planned program for population control is essential for achieving decent quality of life.     

The population,agriculture, and environment nexus in Latin America: country-level evidence from the latter half of the twentieth century

Unprecedented population growth and migration accompanied equally unprecedented land use and land cover change in Latin America during the latter decades of the twentieth century. Country-level data are examined with bivariate statistics to determine relationships between changes in population patterns and land use (agriculture and forest cover) from 1961 to 2001. In South America, large forest areas were eliminated during the period, while exceptionally high rates of forest clearing were ubiquitous in the Central America/Caribbean region. These environmental changes accompanied dissimilar initial population densities and different effects of population change on agriculture. While interacting with a host of political, socio-economic, and geographic processes, it appears that both Malthusian and Boserupian demographic processes were important drivers of deforestation. Given continued, though slowing, population growth, increased urban consumption, and future land use constraints, policy makers face myriad challenges in advancing sustainable agriculture-population dynamics in Latin America.     

Household demographic factors as life cycle determinants of land use in the Amazon

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.     

Some macroeconomic aspects of global population aging

Across the demographic transition, declining mortality followed by declining fertility produces decades of rising support ratios as child dependency falls. These improving support ratios raise per capita consumption, other things equal, but eventually deteriorate as the population ages. Population aging and the forces leading to it can produce not only frightening declines in support ratios but also very substantial increases in productivity and per capita income by raising investment in physical and human capital. Longer life, lower fertility, and population aging all raise the demand for wealth needed to provide for old-age consumption. This leads to increased capital per worker even as aggregate saving rates fall. However, capital per worker may not rise if the increased demand for wealth is satisfied by increased familial or public pension transfers to the elderly. Thus, institutions and policies matter for the consequences of population aging. The accumulation of human capital also varies across the transition. Lower fertility and mortality are associated with higher human capital investment per child, also raising labor productivity. Together, the positive changes due to human and physical capital accumulation will likely outweigh the problems of declining support ratios. We draw on estimates and analyses from the National Transfer Accounts project to illustrate and quantify these points.     

Family structure and well-being at older ages in Japan

The family structure of older Japanese is projected to change dramatically as a result of very low fertility, increasing levels of non-marriage, childlessness, and divorce, and declining intergenerational co-residence. To provide an empirical basis for speculation about the implications of projected increases in single-person and couple-only households, we use two sources of data to describe relationships between family structure and the physical and emotional well-being of Japanese men and women aged 60 and above. We find that marriage is positively associated with self-rated health and emotional well-being among older men but not women. In contrast to expectations, however, we find only limited evidence that the presence of children contributes to well-being. Taken as a whole, our results suggest that declines in marriage may have negative implications for the well-being of older Japanese men while the implications of declines in fertility and intergenerational co-residence may be less than popularly believed.     

Numerical Simulation of Population Distribution in China

A model for simulating population distribution (MSPD) of China is developed based on the grid generation method and the Control of MapObjects of geographical information system. Elevation, net primary productivity, land use and land cover, city sizes and their spatial distribution, and spatial distribution of transport infrastructures are taken into full account in the MSPD. The result from the MSPD shows that in 2000, 90.8% of the total population of China distributed on the southeastern side of the Heihe-Tengchong line. The ratio of population on the northwestern side to total population of China has been increasing since 1935. The yearly growth rate was 0.8% from 1935 to 1990 and 6.1% from 1990 to 2000. One important advantage of the MSPD is that when scenarios of land cover, spatial distributions of transport infrastructures and cities are available, scenarios of spatial population distribution can be developed on the basis of total population forecast.     

Did the Decline in Social Connections Depress Americans’ Happiness?

During the last 30 years US citizens experienced, on average, a decline in reported happiness, social connections, and confidence in institutions. We show that a remarkable portion of the decrease in happiness is predicted by the decline in social connections and confidence in institutions. We carry out our investigation in three steps. First, we run a happiness regression that includes various indicators of social connections and confidence in institutions, alongside with own income, reference income, and the usual socio-demographic controls. We find that indicators of social connections and confidence in institutions are positively and significantly correlated with happiness. Second, we investigate the evolution of social connections and confidence in institutions over time, finding that they generally show a declining trend. Third, we calculate the variation in happiness over time as predicted by each of its statistically significant correlates, finding that the decrease in happiness is mainly predicted by the decline in social connections and by the growth in reference income. More precisely, the sum of the negative changes in happiness predicted by the reduction in social connections and the increase in reference income more than offsets the positive change predicted by the growth of household income. Also, the reduction in happiness predicted by the decline in confidence in institutions is non-negligible, although substantially smaller than the one predicted by either social connections or reference income.     

Household demographic change and land use/land cover change in the Brazilian Amazon

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.

Feeding a growing world

Technology allows for the increased production of food to meet the demands of a rapidly growing population. However, in poor countries, technology may not be economically or environmentally affordable. The balance between food supply and population growth will depend upon government's ability to design and enforce policies and programs to deal with increased population, poverty, and environmental degradation. Approaches will be specific to a country's needs. In Bangladesh, food aid will be needed. In Zaire, political reform will be required. Many countries will have to shift from investments in war to social development. Three kinds of countries will experience difficulty in feeding their populations: 1) countries with little or no reserves of fertile land or water and insufficient funds for food imports; 2) countries that have sufficient reserves of land and water but suffer from government policy failures and neglect of agriculture; and countries with political instability and civil war, which invariably are linked with famine and drought. The future prospects will be a slow increase in dietary intake in most regions, fluctuations in food availability and prices, increased crop yields and land under cultivation, and slower expansion of agricultural lands due to environmental constraints. Pessimists have predicted increased environmental costs of food production due to soil erosion, pesticide contamination of soil and water, loss of species, and fertilizer run-off. Optimists have argued that new lands can be brought under cultivation and investments in agricultural research can help to increase food productivity. As Population Council vice president in the Research Division, John Bongaarts has reiterated that a positive outcome is more likely if population growth can be stopped.     

Climate-related migration in rural Bangladesh: a behavioural model

Research into the climate change and migration nexus has often focussed solely on how people move in response to the impacts of variability and change in climate. This notion often ignores the nature of migration as a tried and tested livelihood choice amid a variety of socio-economic and environmental opportunities and limitations. This paper closely looks at the behavioural aspects of migration decision-making in Bangladesh in the context of changes in its economy, and, increasingly, exposure to the impacts of climate variability and change. We find that villagers in areas particularly affected by increasing climatic stresses and shocks are diversifying their traditional livelihood strategies by migrating. Environmental factors, including climatic stresses and shocks, often make such shifts even more necessary. Although the migrants’ primary motivation is better income, in effect, migration becomes an effective form of adaptation. Based on a qualitative study in three geographically distinct places of Bangladesh, we propose that migration is a socially acceptable behaviour that occurs in the context of perceived environmental change and climate variability. Migration decisions are mediated by a set of ‘behavioural factors’ that assesses the efficacy of different responses to opportunities and challenges, their socio-cultural acceptance and the ability to respond successfully. This understanding has policy relevance for climate change adaptation, in terms of both how migrants are perceived and how their movements are planned for.     

Labor Supply Prospects in 16 Developed Countries, 2000–2050

Over the past 20 years, policy attention has been focused upon the implications of below‐replacement fertility for the aging of populations. This article argues that another potential consequence, a decline in the absolute size of the labor force, may prove to be an equally compelling issue because of its impact on rates of economic growth. Because the United States will experience both increasing labor productivity and an increase in its labor supply, the growth orientation of the global economy is likely to persist. In this circumstance, given relatively comparable changes in the productivity of labor across countries, countries that face major declines in their labor supply will fare less well than countries that are able to maintain their labor supply at least constant. The article examines the labor supply prospects of 16 developed countries for the period 2000–2050, drawing attention to the ways in which countries may be able to influence the future levels of their labor supply.     

A longitudinal study of domestic water conservation behavior

A 1988 study of a school-linked sample in a metropolitan and a regional urban area established baseline data for knowledge, attitudes, intentions, and behavior with regard to water management and conservation (Murphy, Watson, & Moore, 1991). This paper reports on a 1991 follow-up, utilising both longitudinal and cross-sectional samples of students, teachers and parents, which aimed at identifying changes within the community since the initial study. In addition, the study sought to identify factors influential in change and the extent to which the pattern of relationships between knowledge, attitudes, intentions and behaviors had remained stable over time. The results indicated that there was a move towards greater conservation as measured by the variables studied over the three year period, that media interventions and water costs were perceived as influential in this change, and that reported conserving behavior continued to be better predicted by stated intentions than by knowledge. Little difference in the pattern of intervariable relationships was observed across the time span studied.     

Three Centuries of Global Population Growth: A Spatial Referenced Population (Density) Database for 1700–2000

The Earths surface has changed considerably over the past centuries. Since the start of the Industrial Revolution in the early 1700s, humans from the Old World started to colonize the New World. The colonization processes lead to major changes in global land use and land cover. Large parts of the original land cover have been altered (e.g., deforestation), leading to extra emissions of GHGs to the atmosphere and enhancing global climate change. The spatial and temporal aspects are still not very well known. More and more global integrated environmental assessments concerning global sustainability require long time series of global change indicators, of which population is an important one. This study presents an update of the geo-referenced historical population maps for the period 1700–2000, part of the History Database of the Global Environment (HYDE), which can be used in integrated models of global change and/or global sustainability.     

Property Size and Land Cover Change in the Brazilian Amazon

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.     

Settler Welfare on Tropical Forest Frontiers in Latin America

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.     

Fertility Decline,Girls’ Well-being,and Gender Gaps in Children’s Well-being in Poor Countries

The influences of recent dramatic declines in fertility on girls’ and boys’ well-being in poorer countries are understudied. In panels of 67–75 poorer countries, using 152–185 Demographic and Health Surveys spanning 1985–2008, we examined how declining total fertility and women’s increasing median age at first birth were associated with changes in girls’ well-being and gender gaps in children’s well-being, as reflected in their survival, nutrition, and access to preventive healthcare. In adjusted random-effects models, these changes in fertility were associated with gains in girls’ survival at ages 1–4 years, vaccination coverage at ages 12–23 months, and nutrition at 0–36 months (for women’s later first childbearing). Declining total fertility was associated with similar gains for boys and girls with respect to vaccination coverage but intensified gender gaps in mortality at ages 1–4 years and malnutrition at ages 0–36 months, especially in higher-son-preference populations. Later increases in women’s median age at first birth—reflecting more equitable gender norms—were associated with declines in these gaps. Promoting equitable investments in children through family planning programs in higher-fertility societies is warranted.