Projection of the Mexican National Labor Force, 1980–2005

Abstract

Mexico has a large and rapidly growing labor force. This paper projects the Mexican national labor force from 1980 to 2005, with varying assumptions of vital rates, economic activity, and international migration. Projections are also made for the urban and rural components of the Mexican population, assuming inter‐component migration flows. Results indicate that the Mexican labor force will grow over the projection period at an average annual rate of 907,000 to 1,183,000 workers; will age slightly; and will have a much higher proportion female. Implications are discussed in terms of Mexican‐U.S. migration, possible agreements on free trade, and global trends in workforce.     

Rural-to-Urban Labor Migration,Household Livelihoods,and the Rural Environment in Chongqing Municipality,Southwest China

Rural migration and its relationship to the rural environment have attracted increasing research interest in recent decades. Rural migration constitutes a key component of human population movement, while rural areas contain most of the world’s natural resources such as land and forests. This study empirically evaluates a conceptual framework incorporating rural household livelihoods as an integrative mediating factor between rural migration and the rural environment in the context of rural-to-urban labor migration in Chongqing Municipality, Southwest China. The analysis draws on data collected through household surveys and key informant interviews from four villages. Results confirm the hypothesis that labor-migrant and non-labor-migrant households differ significantly in livelihood activities including agricultural production, agricultural technology use, income and consumption, and resource use and management. Implications for the subsequent environmental outcomes of rural labor out-migration and corresponding natural resource management and policy in rural origin areas are discussed.     

Bearing the Burden: Portage Labor as an Adaptive Response to Predictable Food Deficits in Eastern Nepal

Wage work such as portage labor is one of several adaptive strategies by which rural households in Nepal supplement their subsistence agriculture. This study, conducted in the hills of eastern Nepal in 1997, surveyed the landholdings and household subsistence base of 50 commercial porters hired to transport loads from Jiri to various destinations in Solu Khumbu. A major goal was to test the hypothesis that porter households tend to have smaller landholdings than the average household in this region. An unexpected result was that porter households in this study owned nearly as much arable land (1.07 ha) as the mean of 1.15 ha for all hill families in eastern Nepal. Household grain sufficiency correlated significantly (P < 0.01) with farm size (r = 0.53). The majority of the porters lived in villages located at either the origin or the endpoint of their portage work. The study also examined several variables that might explain why portage labor is a full-time occupation for some Nepalis, but a part-time “casual” occupation for others. The most significant difference between households of full-time and part-time porters was the availability of workers at home for managing the household’s land and livestock resources. Households of full-time porters were better able to spare a family member for full-time wage labor because they had significantly more adult workers of either gender (P < 0.05) than households of part-time porters. Full-time and part-time porter households did not differ significantly with regard to family size, land ownership, or number of food-deficit months.     

Mobility strategies and the importance of community ties: former pulp and paper workers in Miramichi,New Brunswick

This article explores how global shifts in capital, production, the labor market, and its segmentation relate to mobility strategies and community ties in a specific local context. Mobility strategies or the refusal to be mobile are, at times, used in order to maintain households in communities that have seen their labor market constrict. Decisions about mobility are not purely about economic rationality. In the mobility strategies employed by former pulp and paper workers from Miramichi, New Brunswick, Canada, resistance to mobility is due to community and familial ties to place. Such local commitments may take precedence over, but are clearly impacted by, the ever-shifting tides of global capital.     

Renegotiating gender and class in the berry fields of Michoacán,Mexico

This article examines the renegotiation of gender and class in a rural Mexican community where economic crisis in the sugar industry led foreign agribusinesses to promote blackberry and raspberry production for export and hire primarily women as berry pickers. Analysis focuses on the transition from a sugar economy where mostly men worked in the cane fields to non-traditional agricultural exports when women entered agricultural waged labor in unprecedented numbers. This restructuring of the regional economy raises important questions regarding the marginalization of differentiated subaltern groups and the nature of new sets of power relations between transnational agribusinesses, berry growers, and waged workers. I analyze the contradictions of this changing social field that connects Northern consumers, transnational company executives, berry growers, and waged laborers in a web of differential power relations as they reverberate along the commodity chain from campesino households to the global market.     

Export agriculture,transnational farmworkers,and labor resistance in the Mexico–US borderlands

This article discusses the system of export agriculture in northern Mexico and its impact on transnational farmworkers employed in both sides of the US–Mexico border. Since the late 1990s, a transnational industry producing fresh produce for consumer markers in the USA has taken hold in the San Quintin Valley in Baja California, transforming the economic and social fabric of this border region. This industry has generated a new labor regime predicated upon the employment of a flexible and cheap source of indigenous workers from the poorest states in southern Mexico. I examine the contours of this regime, the forms of labor resistance it has elicited, and the new types of labor migration it has generated by Mexican workers to the USA. As I show, indigenous farm laborers engage in novel forms of labor and political protests to claim for their rights. These developments, I argue, speak of the class formation of transnational farmworkers who, mobilizing local and transnationally, combine traditional labor demands with wider claims for their civil and political rights.     

Offspring migration and nutritional status of left-behind older adults in rural China

Improvements in nutritional status is a principal pathway to good health. This study examines the effect of migration of adult children on the nutrient intake of left-behind older adults in rural China. We use data from four waves (2004–2011) of the China Health and Nutrition Survey and utilize individual fixed effects methods to panel data. Results show that the migration of offspring is associated with significantly higher nutritional status of their left-behind parents, especially higher intake of proteins, carbohydrates, vitamins B1–B3, phosphorus, magnesium, iron, selenium, and copper. The intake of some of these nutrients is below recommended levels. The magnitude of the estimated effects vary between 4% and 24 %. Older adults who live with their grandchildren in rural households or have a low income benefit more from having adult child migrants in the household. The improvement of nutrition outcomes of left-behind older adults is mainly due to increased consumption of cereals, meat, eggs, and fish.     

陕北小流域退耕农户剖面特征的土地利用决策响应

采用基于GIS的空间分析、数理统计(Mathematical Statistics)与Multi-logistic回归模型相结合的方法(GMM),探讨退耕前后陕北燕沟流域土地利用及其关键的社会经济驱动因素的变化,揭示农村劳动力转移在土地利用决策中的重要性,了解农村土地利用变化的驱动机制。结果表明:(1)1990—2013年,流域土地利用变化特征总体上与延安市的土地利用变化趋势一致,即坡耕地减少和林草地增加显著;(2)1990—2001年,农业劳动力转移对农户土地利用决策的影响不明显,农户家庭基本特征与资源禀赋等对农户土地利用决策的影响显著。2001—2013年,劳动力转移和交通条件对农户土地利用决策有显著影响,退耕还林政策对农村劳动力的再分配产生了较大影响。     

Division of labor inPonera pennsylvannica (Formicidae: Ponerinae)

Summary We examined division of labor and colony demography in the antPonera pennsylvannica. Observation of three colonies with individually marked workers revealed a high degree of interindividual behavioral variation and a rough but consistent division of labor between brood tenders and foragers. This division was present both in colonies consisting entirely of workers produced in the previous summer and in colonies containing freshly eclosed ants. Two colonies showed typical age-based polyethism, with young ants focusing on brood care and overwintered ants on foraging. No such age basis was detected in the third colony. This difference may relate to variability in brood production schedules. Colonies showing temporal polyethism had two peaks of brood production and thus had relatively large brood populations when the first young workers eclosed, while the third colony had only one peak and little brood for the young workers to tend. Even if young ants have a lower threshold for brood care, it may have been concealed in the latter situation. Demographic data indicate that natural colonies produce one brood per year and that workers typically eclose into colonies with relatively low brood care demands. This suggests that overwintered workers do most of a colony's work and that the division of labor among overwintered ants is the more important one under natural conditions. The basis of this division is as yet unknown. These results also suggest that small colony size, univoltine brood schedule and a close association between foraging and brood care do not preclude division of labor among specialized castes, as has been suggested for another ponerine species (Traniello 1978).     

Rural to Urban Migration Is an Unforeseen Impact of Development Intervention in Ethiopia

Rural development initiatives across the developing world are designed to improve community well-being and livelihoods. However they may also have unforeseen consequences, in some cases placing further demands on stretched public services. In this paper we use data from a longitudinal study of five Ethiopian villages to investigate the impact of a recent rural development initiative, installing village-level water taps, on rural to urban migration of young adults. Our previous research has identified that tap stands dramatically reduced child mortality, but were also associated with increased fertility. We demonstrate that the installation of taps is associated with increased rural-urban migration of young adults (15–30 years) over a 15 year period (15.5% migrate out, n = 1912 from 1280 rural households). Young adults with access to this rural development intervention had three times the relative risk of migrating to urban centres compared to those without the development. We also identify that family dynamics, specifically sibling competition for limited household resources (e.g. food, heritable land and marriage opportunities), are key to understanding the timing of out-migration. Birth of a younger sibling doubled the odds of out-migration and starting married life reduced it. Rural out-migration appears to be a response to increasing rural resource scarcity, principally competition for agricultural land. Strategies for livelihood diversification include education and off-farm casual wage-labour. However, jobs and services are limited in urban centres, few migrants send large cash remittances back to their families, and most return to their villages within one year without advanced qualifications. One benefit for returning migrants may be through enhanced social prestige and mate-acquisition on return to rural areas. These findings have wide implications for current understanding of the processes which initiate rural-to-urban migration and transitions to low fertility, as well as for the design and implementation of development intervention across the rural and urban developing world.     

Present situation and future perspectives for goat production systems in Spain

This article presents the evolution, actual situation and prospects for goat production systems in Spain, taking into account the present day changes of socio-economic, technological and agricultural policies of the European Union (EU). Spain is ranked second in goat population and third in goat milk yield within the EU, nevertheless, similar to the situation in the EU, the goat production systems in Spain are in a critical situation, basically because of the increasing production costs and the lack of a strong central structure in this sector. To improve viability of goat farms in Spain, which, for the most part play an important social and environmental role in the less-developed rural areas, it is necessary to establish a series of strategies. These strategies include: (i) strengthening of the central structure in the sector; (ii) improvement in the training and management capacity of goat farmers and cheese makers; (iii) enhancement of promotion and recognition of goat-related products; (iv) taking advantage of the opportunities offered by the new European Union Common Agricultural Policy; (v) improvement of farmers’ quality of life, so that they can maintain their goat operations for future generations; and (vi) increasing development and research activities in this sub-sector of livestock farming.     

Nutritional status of Ribeirinhos in Brazil and the nutrition transition

Anthropometric and household data (size, composition, economic activity) were collected from a population of Ribeirinhos living in a rural setting in the eastern Amazon. Data are compared to international reference standards and to other Amazonian populations with the goals of increasing our understanding of the Amazon's largest ethnic group and identifying the relationship between changes in subsistence strategies and nutritional status. Data on height, weight, skinfolds, and circumferences were collected from 471 adults and subadults. The population showed a high degree of stunting with an average HAZ below -2.0 for all age groups over 3 years, and 60% of adult men and 70% of adult women were stunted. Wasting was rare. Average skinfold thicknesses and upper-arm muscle area were near or below average but within the normal range compared to the reference standard, indicating adequate energy and protein stores. Thirty-one percent of males and 29% of females were overweight/obese, and the highest average BMIs were found among men and women in their 40s. Adult males who participated in wage labor had higher weights, BMIs, and UMA values, and were more likely to be overweight and obese compared with those who did not work in wage-labor jobs. Children of fathers who worked in wage labor had higher BMI and UMA values, but there was no significant effect on the nutritional status of other adults in these same households. Signs of the nutrition transition were most noticeable among adult males involved in wage labor because of changes in their diet and activity patterns.     

Adult honeybees (Apis mellifera L.) abandon hemocytic, but not phenoloxidase-based immunity

Hemocytes and the (prophenol-) phenoloxidase system constitute the immediate innate immune system in insects. These components of insect immunity are present at any post-embryonic life stage without previous infection. Differences between individuals and species in these immune parameters can reflect differences in infection risk, life expectancy, and biological function. In honeybees which show an age-related division of labor within the worker caste, previous studies demonstrated that foragers show a strongly reduced number of hemoctyes compared to the younger nurse bees. This loss of immune competence has been regarded advantageous with respect to an already high mortality rate due to foraging and to redistribution of energy costs at the colony level. Based on the idea that abandoning hemocytes in all adults would be a reasonably direct regulatory mechanism, we posed the hypothesis that abandoning hemocytic immunity is not restricted to worker honeybees. We tested our hypotheses by performing a comprehensive analysis of hemocyte number and phenoloxidase (PO)-activity levels in immunologically naive workers, queens, and drones. We found that in all three adult phenotypes hemocyte number is dramatically reduced in early adult life. In contrast, we found that the dynamics of PO-activity levels have sex and caste-specific characteristics. In workers, PO activity reached a plateau within the first week of adult life, and in queens enzyme levels continuously increased with age and reached levels twice as high as those found in workers. PO-activity levels slightly declined with age in drones. These data support our hypothesis, from which we infer that the previously reported reduction of hemocyte in foragers is not worker specific but represents a general phenomenon occurring in all honeybee adult phenotypes.     

农户薪柴消费的理论模型及实证研究

农户薪柴消费变化对室内空气质量、农村生态环境建设影响重大,论文构建了山区农户薪柴消费的理论模型,以重庆市典型区1015份农户调查数据为例,运用Tobit模型分析了农户人均薪柴消费量的影响因素。研究表明:农户家庭能源消费中,商品能源和新能源的比重逐步增大,但薪柴依旧是农户普遍使用的能源类型,且消费量占总能源消费量的比重高;通过降低农业劳动力比重和提高非农工资水平两种途径,非农就业能显著降低农户人均薪柴消费量;家庭电器数量增多、其他收入(政府补贴、亲戚帮扶等)增加、及替代能源(液化气、沼气、煤炭等)可获得性增强也能显著降低农户人均薪柴消费量,而户主年龄大、人均牲畜数量多及房屋离集市距离远的农户家庭的人均薪柴消费量高。提出了加快薪柴替代的措施。     

The one-person household in Latin America: a brief note.

Drawing from World Fertility Survey and UN Demographic Yearbook data, this short paper considers the prevalence and composition of 1-person households in selected countries of the world, with particular attention to Latin America and the United States. In descending order of prevalence, 1-person households are most prevalent in Western culture group countries, Southern and Eastern Europe, sub-Saharan Africa, Latin America, Asia, and the Middle East. The proportion of these households is in fact growing in both the U.S. and Europe, and is associated with a growing proportion of elderly in the population, and a growing tendency among young adults to leave their parents' homes before marriage. Accordingly, most 1-person households are comprised of those young and never-married, and old and formerly-married. Debate remains over whether this trend is primarily influenced by growing affluence or changing ideas. This pattern contrasts sharply with that observed in Latin America. There, a majority of elderly live in extended households, most youths reside at parents' home until marriage, and many middle-age adults live alone. This latter phenomenon may result from comparatively higher levels of marital disruption and migration. A larger proportion of 1-person householders are therefore outside of the 2 aforementioned majority groups observed in the U.S. In closing, the paper again observes the difference between the 2 patterns, yet fails to speculate upon whether the Latin American pattern will grow to resemble that found in the U.S. and Europe.     

American political culture and the shifting meaning of race

This study of undocumented immigrant Nepalese workers in Japan analyses their ethnic history, demographics, migration strategies and work experiences. The majority belong to ethnic groups which the British designated 'martial races', whose tradition of foreign service as 'Gurkha' soldiers in the British and Indian Armies produced a culture of emigration and a remittance economy in rural Nepal. As a result, the present generation has been socialized to be familiar with international migration as an economic option, and has access to networks for its accomplishment. Japan's industrial structure and relative affluence have generated chronic shortages of workers to fill jobs shunned by Japanese in manufacturing and construction industries. This has elevated wages to levels which attract economically distressed foreign migrants such as those from Nepal. Despite the isolation and discrimination which they suffer, these Nepalese find the financial rewards to be sufficient to outweigh the hardships.     

Impact of wind farms on soaring bird populations at a migratory bottleneck

Collision with turbines at wind farms is expected to have a greater impact on birds at particular sites where high concentrations of individuals occur, such as migration bottleneck areas. The Strait of Gibraltar (southern Spain) has long been recognized as the most important bottleneck in western Europe for soaring bird migration. Moreover, this area is within one of the most important potential areas for wind energy generation in Spain. Here, we examine monthly migratory soaring bird abundance in relation to long-term avian mortality rates at 21 wind farms located near the Strait of Gibraltar using zero-inflated hurdle negative binomial and gamma models. Best fit models included an effect of season in the collision mortality rates and in the proportion of adult individuals within the total deaths. However, monthly bird abundance was not directly related to the number of fatalities over the year. The accumulated fatalities during autumn migration constitute a small percentage (1%) of the total migrating population size. Moreover, mortality peak during autumn migration is largely attributable to juvenile birds. In contrast, the number of fatalities coinciding with the breeding period constitutes a substantial proportion (6%) of the local population, and it involved substantial losses among adult birds. Our results show that wind farms probably have an individually low impact on the migratory population of soaring birds. On the contrary, annual losses among adult local birds are remarkably high considering the small size of the local populations, and they may have population level effects.     

Economic migrants and the labour market in Spain and Portugal

Within the last fifteen years Spain and Portugal have begun to experience a phenomenon that occurred in northern Europe three or four decades earlier. Rising prosperity, an ageing population, and growing labour shortages have triggered a demand for foreign labour in the Iberian economies. This survey article identifies the changing trends and developments of recent immigration to two southern European countries, and the problems of labour market integration. It compares and contrasts the insertion process in Spain and Portugal and highlights the policy dilemma that, like most of the rest of the EU, the Iberian economies require immigrant workers, but have yet to develop effective mechanisms for integrating them. It argues that the labour market is not only the principal mechanism by which immigrants are integrated, but is beginning to transform attitudes towards immigration. Employer organizations have played a lead role in pressing for a shift from restriction and control to the management of immigrant integration. However, the needs of employers, who require a supply of cheap, flexible labour clashes with the government's exclusion policy, as the case study based on Lorca, Spain demonstrates.     

Physiological correlates of division of labor among similarly aged honey bees

Hormone analyses and exocrine gland measurements were made to probe for physiological correlates of division of labor among similarly aged adult worker honey bees (Apis mellifera L.). Middle-age bees (ca. 2 weeks old) performing different tasks showed significant differences in both juvenile hormone (JH) biosynthesis rates and hemolymph titers; guards and undertakers had high JH, and wax producers and food storers, low JH. Guards and undertakers had similar hormone levels to foragers, even though they were 10 days younger than foragers. No differences in JH were detected among young bees (1-week-old queen attendants and nurses) or older bees (3–4 week-old pollen foragers, non-pollen foragers, and soldiers). Hypopharyngeal gland size was inversely correlated with worker age and rate of JH biosynthesis, but soldiers had significantly larger hypopharyngeal glands than did foragers, despite their similar age and JH level. Results from soldiers indicate that exocrine gland development is not always linked with age-related behavior and endocrine development; they also support the recent claim that soldiers constitute a group of older bees that are distinct from foragers. Hormonal analyses indicate that the current model of JH's role in honey bee division of labor needs to be expanded because high levels of JH are associated with several other tasks besides foraging. JH may be involved in the regulation of division of labor among similarly aged workers in addition to its role in age-related division of labor.Abbreviations JH Juvenile hormone - RIA radioimmunoassay - CA corpora allata - HPLC high performance liquid chromatography - TLC thin layer chromatography     

Flexible division of labor mediated by social interactions in an insect colony-a simulation model

The primitively eusocial wasp Ropalidia marginata shows an age-based division of labor in which workers allocate tasks according to their relative ages (age ranks). This age polyethism seems quite flexible because in colonies devoid of old workers, young individuals can perform the tasks normally performed by older workers. Social interactions appear to be a plausible mechanism by which workers can assess their relative ages. To explore possible proximate mechanisms that can potentially generate such a flexible, age-based task allocation, the activator-inhibitor model was adapted to the social biology of R. marginata and tested using computer simulations. The model generated a clear age polyethism including the phenomena of precocious foragers in colonies with only young individuals and reverted nurses in colonies consisting of only old individuals. A simple extension of the model to allow the brood:adult ratio to modulate the rates of social interactions, shows how increasing task demands can be met by a decrease in the ages of first performance of, and an increase in the proportions of individuals engaged in, various tasks. These results show how a pattern of division of labor based on relative age can be generated and modulated by social interactions. Copyright 1999 Academic Press.