Environmental quality and fertility: the effects of plant density,species richness,and plant diversity on fertility limitation

The relationship between the environment and population has been of concern for centuries, and climate change is making this an even more pressing area of study. In poor rural areas, declining environmental conditions may elicit changes in family-related behaviors. This paper explores this relationship in rural Nepal looking specifically at how plant density, species richness, and plant diversity are related to women’s fertility limitation behavior. Taking advantage of a unique data set with detailed micro-level environmental measures and individual fertility behavior, I link geographically weighted measures of flora at one point in time to women’s later contraceptive use as a way to examine this complex relationship. I find a significant, positive relationship between plant density, species richness, and plant diversity and the timing of contraceptive use. Women in poor environmental conditions are less likely to terminate childbearing, or do so later, and therefore more likely to have larger families.     

Do Rainfall Deficits Predict U.S.-Bound Migration from Rural Mexico? Evidence from the Mexican Census

Environmental and climatic changes have shaped human mobility for thousands of years and research on the migration-environment connection has proliferated in the past several years. Even so, little work has focused on Latin America or on international movement. Given rural Mexico’s dependency on primary sector activities involving various natural resources, and the existence of well-established transnational migrant networks, we investigate the association between rainfall patterns and U.S.-bound migration from rural locales, a topic of increasing policy relevance. The new economics of labor migration theory provides background, positing that migration represents a household-level risk management strategy. We use data from the year 2000 Mexican census for rural localities and socioeconomic and state-level precipitation data provided by the Mexican National Institute for Statistics and Geography. Multilevel models assess the impact of rainfall change on household-level international out-migration while controlling for relevant sociodemographic and economic factors. A decrease in precipitation is significantly associated with U.S.-bound migration, but only for dry Mexican states. This finding suggests that programs and policies aimed at reducing Mexico-U.S. migration should seek to diminish the climate/weather vulnerability of rural Mexican households, for example by supporting sustainable irrigation systems and subsidizing drought-resistant crops.     

Land cover change and fertility in West-Central Africa: rural livelihoods and the vicious circle model

The vicious circle argument, rooted in a neo-Malthusian tradition, states that resource scarcity increases the demand for child labor and leads to higher fertility. The rural livelihood framework, on the other hand, contends that households employ multiple strategies, only one of which involves adjusting their fertility levels as a response to environmental pressures. This study provides a unique test of both theories by examining the relationship between land cover change and fertility across hundreds of rural communities in four West-Central African countries. The findings reveal a complex relationship between natural capital and fertility. In communities where natural capital was initially low, a further decline in that capital is associated with both higher fertility preferences and levels. However, we find that fertility preferences and behavior are often discordant, with notable within-community differences in response to decline in natural capital across levels of household wealth.     

Fertility and land availability in rural Brazil

Differences between the marital fertility of the agricultural frontier and that of the more settled rural areas of southern Brazil are analyzed in this paper. Fertility rates derived from 1970 census data appear to decrease as the degree of settlement increases, suggesting an experience parallel to the decline in U.S. rural fertility in the late nineteenth century, which Easterlin and others have attributed to increased scarcity of land for starting new farm households. Multivariate analysis of the Brazilian data shows parallels between the two situations but also reveals that the importance of literacy, child survival, and access to land is relatively greater than that of the availability of land for explaining fertility differentials in Brazil.     

The age at first birth and timing of the second in Costa Rica and Guatemala

This paper explores the relationship between the age at first birth and the timing of subsequent fertility in Costa Rica and in four rural villages and two urban areas of Guatemala. The results indicate that, for Costa Rica, the age at first birth is significantly related to the tempo of subsequent births, and that this association, at least for the interval to second birth, remains significant when socio-economic factors and marital status at the time of first birth are held constant. While the results suggest that the age at first birth is related to timing of the second in the Guatemalan sample as well, the association is weaker and less consistent than in Costa Rica.     

The influence of rural-urban migration on migrants' fertility in Korea,Mexico and Cameroon

The paper presents a comparative analysis of the relationship between rural-urban migration and fertility in Korea, Mexico, and Cameroon. Using an autoregressive model, the results show a significant rural-urban migration adaptation effect in Korea and Mexico, a reduction of 2.57 and 1.45 children during the entire childbearing period, respectively, when compared to a rural stayer, even after the effect of selection has been controlled. Rural-urban migration has a very small impact on fertility in Cameroon. The unexpected result for Cameroon is due to the fact that the fertility-increasing effect of urban residency on the improved supply conditions of births, such as reduced infertility, offsets the fertility-depressing effect of urban residency on the demand for births. As a result of the adaptation to urban fertility norms, the number of country-wide births was reduced significantly in Mexico and Korea over the time periods studied.     

Population and Resources: An Exploration of Reproductive and Environmental Externalities

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.     

Environmental Influences on Human Migration in Rural Ecuador

The question of whether environmental conditions influence human migration has recently gained considerable attention, driven by claims that global environmental change will displace large populations. Despite this high level of interest, few quantitative studies have investigated the potential effects of environmental factors on migration, particularly in the developing world and for gradual but pervasive forms of environmental change. To address this, a retrospective migration survey was conducted in rural Ecuador and linked to data on topography, climate, and weather shocks. These data were used to estimate multivariate event history models of alternative forms of mobility (local mobility, internal migration, and international migration), controlling for a large number of covariates. This approach is generalizable to other study areas and responds to calls for the development of more rigorous methods in this field. The results indicate that adverse environmental conditions do not consistently increase rural out-migration and, in some cases, reduce migration. Instead, households respond to environmental factors in diverse ways, resulting in complex migratory responses. Overall, the results support an alternative narrative of environmentally induced migration that recognizes the adaptability of rural households in responding to environmental change.     

Income inequality and fertility: A comparative view

Summary Most studies pertaining to the relationship between population and economic development suffer from a major flaw. Researchers use aggregate measures like income or energy consumption per head as indicators of economic development. Such aggregate measures fail to take into account the nature of the distribution of income or energy consumption to the population. The present study attempts to demonstrate the importance of incorporating the nature of distribution of resources as an important intervening variable in the study of the overall relationship between population and economic development. A measure of income inequality is developed which represents the difference between rural and urban incomes. This measure is justified in terms of the distinctiveness of urban and rural sectors in the process of development. The data used relate to societal measures of fertility, income, income inequality, etc. Consistently with existing literature, we observe that, generally speaking, economic development does entail a reduction in rural-urban income inequalities. On the other hand, a substantial part of the negative effect of an increase in income per head can be nullified if such an increase were not also accompanied by a reduction in rural-urban income inequality. Also, a substantial part of the negative effect of an increase in income per head and the level of education in reducing the level of infant mortality would be nullified if it did not also result in a reduction of rural-urban income inequality. On the other hand, it is quite possible for the level of education in a society to increase together with an increase in income per head without substantially altering the extent of inequality of income between the rural and the urban population. It is suggested that the positive relationship between rural-urban income inequality and the level of fertility is due to higher rural fertility rates in a high-inequality country. By implication, this would mean that higher standards of living for the rural population compared with its urban counterpart will have a favourable impact in reducing rural fertility.     

中国人口迁移与生育率关系研究

本文利用2000年人口普查数据,考察了中国人口迁移与生育率的关系。通过比较农村本地人口、城市本地人口和流动迁移人口三个人口群体在生育率上的差异,并进行多元统计分析,结果表明,流动迁移对生育率有着非常显著影响,城市外来人口的生育率不仅显著低于农村本地人口,而且也低于城市本地人口;远期流迁人口的生育率要低于近期流迁人口的生育率。中国人口迁移与生育率的关系出现了与已有的迁移生育率理论的不一致。1990年代中国的迁移生育率发生了转变。     

Period Parity Progression Measures of Fertility in China

Parity progression measures are uniquely suited to the study of fertility in China, because Chinese policies and programmes focus so closely on parity and birth order. In this paper we present period parity progression ratios for China and its urban and rural areas for the years 1955–81, using the birth history data from the one-per-thousand fertility survey of 1982. Our period parity progression ratios differ from those introduced by Henry in that they provide an overall level of fertility which may be compared with measures based on age-specific birth rates. We compare the two measures empirically for China, finding both similarities and divergences, and then analyse the relation between them. It is suggested that, where fertility is low and fluctuating, as in China, the parity-progression-based measures provide a substantially truer picture of fertility levels and trends than do age-based measures.     

Rural–urban migration, agrarian change, and the environment in Kenya: a critical review of the literature

The nexus between migration dynamics and environmental change has drawn the attention of many researchers in the recent past. While the majority of studies focus on the impact of the environment on migration decisions, less emphasis has been placed on the feedback effect of migration on the environment in rural sending areas. This article provides a critical review of this relationship by focusing on the rich literature on rural–urban migration of smallholder households in Kenya and its effects on rural environments. The article argues that there are distinct relations between migration, agricultural change and the environment. These are mediated in varying degrees by flows of remittances, loss of labor, socioeconomic stratification, gender dynamics, and cultural factors. Overly generalizing assumptions about these relations, however, fail to grasp their complexity. We propose employing a translocal perspective to enrich future analysis and enhance the understanding of migration–environmental interactions.     

Household access to capital and its effects on drought adaptation and migration: a case study of rural Alberta in the 1930s

This article reports findings from an empirical study of the impacts of drought on rural households in southeastern Alberta, Canada during the 1930s. In that decade, extreme summer heat conditions and low precipitation levels led to repeated crop failures. These extreme climatic conditions coincided with economic recession, falling commodity prices, and rising unemployment to create widespread hardship and suffering across the rural population. Thousands of households adapted by leaving the drought-stricken region and migrating to more northerly regions unaffected by drought, often suffering still further hardship as they reestablished themselves in a new environment. Through secondary research of historical documents and interviews with surviving migrants and non-migrants, this study identifies how economic, human, and social capital influenced the adaptive capacity, adaptation decisions, and migration behavior of rural households and describes how institutional responses affected household adaptation. Differential access to capital in its various forms was a key factor that distinguished households that adapted via migration from those that did not. The findings from this study of historical environment-related population change provide insights that enhance our broader understanding of potential future migration responses to the impacts of anthropogenic climate change and important considerations for policy-makers and planners seeking to build adaptive capacity in rural populations.     

Environmental Change,Risky Sexual Behavior,and the HIV/AIDS Pandemic: Linkages Through Livelihoods in Rural Haiti

Local natural resources are central to rural livelihoods across much of the developing world. Such “natural capital” represents one of several types of assets available to households as they craft livelihood strategies. In order to explore the potential for environmental scarcity and change to contribute to perpetuation of the HIV/AIDS pandemic, we examine the association between declining natural capital and engaging in risky sexual behaviors, as potentially another livelihood strategy. Such an association has been demonstrated in Kenya and Tanzania, through the fish-for-sex trade. To explore the possibility of this connection within rural Haitian livelihoods we use Demographic and Health Survey data, with a focus on rural women, combined with vegetation measures generated from satellite imagery. We find that lack of condom use in recent sexual encounters is associated with local environmental scarcity—controlling for respondent age, education, religion and knowledge of AIDS preventive measures. The results suggest that explicit consideration of the environmental dimensions of HIV/AIDS may be of relevance in scholarship examining factors shaping the pandemic.     

Migrant fertility in Ghana: selection versus adaptation and disruption as causal mechanisms

The aim of the study presented in this paper is to disentangle the roles of three mechanisms -- selection, adaptation, and disruption -- in influencing migrant fertility in Ghana. Using data from the 1998 Ghana Demographic and Health Survey, we fit Poisson and sequential logit regression models to discern the effects of the above mechanisms on cumulative fertility and annual probabilities of birth. Characteristics of migrants from four types of migration stream are examined and compared with those of non-migrants at origin and destination. We find substantial support for the selection hypothesis among both rural-urban and urban-rural migrants. Disruption is evident only in the fertility timing of second and higher-order births in Ghana. Our finding that migrants bear children at about the same rates as the natives at destination implies that the growth rate of cities will slow down quickly and that the rural population will continue to have high fertility. Thus to achieve a reduction in the national fertility level, family planning activities need to be directed towards rural areas.     

Interrelations between migration and fertility in Thailand

Based on special tabulations of 1960 census data on migration within Thailand, this analysis attempts to assess the role of migration in the urbanization process and the relation between migration and fertility. The importance of migration to urban growth is evidenced by the clearcut positive relationship between the percentage of persons classified as either lifetime or 5-year migrants and the urban character of their 1960 place of residence. Yet, the evidence also points to an increasing proportion of urban growth in recent decades attributable to natural increase. The specific relation between fertility and migration varies depending on the measure of migration used: Compared to nonmigrants in their place of destination, the fertility levels of lifetime migrants are not very different; but those of 5-year migrants are considerably lower. Regardless of migration status, however, fertility level is markedly lower for those living in urban places compared to those in rural places. This suggests the important role of both migration and urbanization in affecting fertility levels in Thailand.     

Latin American Households in Comparative Perspective

Comparative family sociology has had little to say about the Latin American family or household despite it links to a European colonial culture mixed with a distinct set of indigenous and historical circumstances. In this paper tentative judgements are put forward about the similarities and differences between the Western and Latin American household by examining four of its dimensions: the household's relative complexity, the separate residence of conjugal units, the incidence of households headed by women, and the incidence of household members being unrelated to the head. Data come from the World Fertility Survey household files gathered during the middle 1970s in six countries: Mexico, Costa Rica, Panama, the Dominican Republic, Colombia and Peru. We find that household complexity in the six countries is intermediate between that of the West and East. Many of the households are extended laterally instead of vertically, because conjugal couples tend to reside in separate households, but often live with unmarried relatives as well. In addition, a high level of marital instability results in a significant proportion of households headed by women, many of them containing members of the extended family. Finally, whereas the circulation of young unmarried people of both sexes was common in rural areas in the West, being an unrelated individual in another's household is most common in urban areas among females between 15 and 19 years old.     

Demographic response to environmental pressure in Malawi

The discussion in this paper uses Malawi as a case study to shed some light on the interrelationships between population growth and demographic responses to environmental pressure. It is noted that certain parts of the country that are experiencing extreme environmental stress have began to go through a rapid phase of demographic and social change and transformation. For example, the Southern Region of the country, which has some of the highest densities, is experiencing a fertility transition. There is a spontaneous internal migration pattern from densely populated rural areas to other sparsely populated rural areas. Other non-demographic responses to population pressures are also briefly discussed in this paper.     

The effects of income level,income distribution,education and urbanization on fertility rates among 28 administrative regions of China

Conflicting empirical evidence on the role of income distribution on fertility rates is the impetus for this 1982 study of providence-specific Chinese Census data, excluding Tibet. The findings support the prior thesis of Repetto but utilize the micromethods and per household income measures of the competing findings of Boulier. It is cautioned that in the Chinese analysis equal income distribution depresses fertility, but China may not reflect world wide patterns. China did not have until recently a market incentive system, and there are income measurement problems. The data are per capita economic output not per capita income, and those high output areas which did not produce low fertility may actually have had households with low incomes. The importance of this research is in establishing that cross-province data are a useful tool in understanding the influence of income distribution on fertility. As with most developing countries, women's education, for instance, at least junior high education explained the largest variation of fertility differences among the 28 provinces. The urbanization variable when controlling for income was positive, unlike the other developing countries. The 1949 Chinese government's spatial industrial policy encouraged urbanization and industrialization in rural areas and family planning programs such that highly urbanized provinces have low population density. A variety of variables on income level, income distribution, education, and urbanization are discussed. OLSQ regressions were generated utilizing such independent variables as output per capita in yuan (YOUTHPC80), the square of YOUTHPC80 (YOUTHPC802), YOUTHPC80 multiplied by the average family size in each province (YOUTHPH80), and the squared value of YOUTHPH80.