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1.
This article assesses the relationship between demographic change and structural adjustments in agriculture. A number of demographic and economic analyses have posited an inverse relationship between post-1950 exurban population growth and agricultural viability, especially in the Northeast Region of the USA. To test this hypothesis, a multivariate model of percent change in county land in farms over the period 1950–1987 is estimated, and the findings only partially support the population hypothesis. Estimation results indicate that the effect of core metropolitan status is significant, but that the effects of rural population change, rural nonfarm population change, and county population deconcentration are not. The analysis demonstrates that maintenance of land in farm use largely depends upon economic forces that are national and regional in scope, and almost exclusively outside the purview of state and local farmland protection programs.  相似文献   

2.
Property Size and Land Cover Change in the Brazilian Amazon   总被引:1,自引:0,他引:1  
This paper considers the size of a farmer’s property as a key variable influencing land cover and land cover change in rural areas of developing countries. Data from 126 rural familial properties in the region around the city of Santarém, Pará, in the Brazilian Amazon, indicate that property size is important for understanding the trajectories of land cover change. Past research has focused on the distinction between small family farms and large capitalized farms, arguing that family farmers have a higher deforestation intensity, or on estimating the strength of the effect of property size relative to economic or demographic factors. This paper shows that larger familial properties are able both to retain a larger area in forest and to have long enough cycles of use and fallow to allow previously used land to become forested again. Based on these analyses and discussion, we argue that land use and land cover research must consider property size as an organizing principle in order to better comprehend the reciprocal relationship between population and environment in frontier areas of the Brazilian Amazon and other rural landscapes.  相似文献   

3.
In this exploratory study, we decompose population growth and decline into their constituent elements to examine how demographic change drives environmental change. Using the example of land development, the analysis integrates county-level measures of births, deaths, in-migration, and out-migration with data on built-up land area from the National Land Cover Database for the years 2001–2006 and then 2006–2011. Drawing from human ecology and environmental demography, we hypothesize that the components of population change will have asymmetric impacts on the construction of the built environment as a form of land development. Results from spatial error models, with a contemporaneous and a temporarily lagged dependent variable, show conditional support for these hypotheses. While each component of demographic change has a unique effect on the dependent variable, the rate at which births increase built-up land area is significantly greater than the rate at which deaths slow this process down.  相似文献   

4.
Demographers have much to contribute to climate change science. This paper describes a new framework being developed by the climate research community that holds potential as an organizing tool for population–climate scholarship, as well as being useful for identifying demographic research gaps within the climate change field. The shared socio-economic pathways (SSPs) represent plausible alternative trends in the evolution of social and natural systems over the twenty-first century at the scale of the world and large regions. The SSPs can help identify population–environment research gaps by illuminating areas of intersection that will shape climate futures but require deeper scientific understanding—the association between urbanization and energy consumption is an example. Also, to vastly enhance the policy relevance of local case studies, the parameters outlined within the SSPs can offer a basic level of harmonization to facilitate generalization. In this way, the SSP framework can increase the relevance and accessibility of population research and, therefore, offer a mechanism through which demographic science can truly offer policy impact.  相似文献   

5.
The influence of environmental conditions on fertility decision-making is becoming increasingly important in the context of contemporary climate change. Deforestation, land availability, and environmental quality may shape decisions regarding family size, particularly in regions with high levels of natural resource dependence. This research examines the relationship between fertility timing and precipitation in rural Mexico by linking household event-history data to municipal-level precipitation measures. Even after controlling for other factors that impact fertility, in historically dry areas, households are more likely to have a child following above average precipitation, using both 1-year and 2-year prior precipitation measures. Conversely, the relationship between precipitation and fertility timing in humid areas of rural Mexico is not statistically significant. Overall, the findings reveal that the fertility-environment connection is highly context-specific and differs across climate zones in Mexico, but that fertility timing is associated with recent rainfall patterns for households in dry areas of rural Mexico.  相似文献   

6.
How do Recent Population Trends Matter to Climate Change?   总被引:2,自引:0,他引:2  
Although integrated assessment models (IAM) of the Intergovernmental Panel on Climate Change (IPCC) consider population as one of the root causes of greenhouse gas emissions, how population dynamics affect climate change is still under debate. Population is rarely mentioned in policy debates on climate change. Studies in the past decade have added significantly to understanding the mechanisms and complexity of population and climate interactions. In addition to the growth of total population size, research shows that changes in population composition (i.e. age, urban–rural residence, and household structure) generate substantial effects on the climate system. Moreover, studies by the impact, vulnerability and adaptation (IAV) community also reveal that population dynamics are critical in the near term for building climate change resilience and within adaptation strategies. This paper explores how global population dynamics affect carbon emissions and climate systems, how recent demographic trends matter to worldwide efforts to adapt to climate change, and how population policies could make differences for climate change mitigation and adaptation.  相似文献   

7.
This is a study of migration responses to climate shocks. We construct an agent-based model that incorporates dynamic linkages between demographic behaviors, such as migration, marriage, and births, and agriculture and land use, which depend on rainfall patterns. The rules and parameterization of our model are empirically derived from qualitative and quantitative analyses of a well-studied demographic field site, Nang Rong district, northeast Thailand. With this model, we simulate patterns of migration under four weather regimes in a rice economy: (1) a reference, “normal” scenario; (2) 7 years of unusually wet weather; (3) 7 years of unusually dry weather; and (4) 7 years of extremely variable weather. Results show relatively small impacts on migration. Experiments with the model show that existing high migration rates and strong selection factors, which are unaffected by climate change, are likely responsible for the weak migration response.  相似文献   

8.
文章利用江苏、山东和安徽省30个县的调查数据,描述了农村人口应对气候变化行动的意愿分布,分析了其参与应对气候变化行动意愿的影响因素。实证结果表明,气候变化对农业收入及农民生活的影响程度、性别、气候变化的了解和关注程度、国内外气候变化行动了解程度、国际节能减排期待、国内政府实施和促进农业清洁生产的期待对农村人口应对气候变化行动意愿有显著影响。建议政府因势利导,帮助农村人口适应气候变化,促进农业生产。  相似文献   

9.
Family planning (FP) in rural China, particularly the ramifications of the 1-child policy, has profound implications and ramifications for family-centered social and economic life in addition to demographic control. Under a constitutionally endorsed policy of strict birth control, favorable economic opportunities coexisted with the problem of familial labor shortages. Recent reform policies have led to a more relaxed FP environment. The Chinese state is in a dilemma between the need to allow peasant's autonomy in determining the familial work situation and the population pressure on the limited cultivated land. The Chinese experience of rural reform is examined in terms of the complex relationship between population change and economic development which are influenced by the production and welfare activities of the peasant family. The theoretical argument is that a family reliant strategy of economic reform undercuts the effectiveness of population control programs. The ultimate solution lies with sustained industrialization with high labor absorption. National trends and the Dahe People's Commune/Township experience are analyzed. Discussion is focused on the dilemma of FP and family production, old and new evidence of family size and economic performance, welfare outcome of family size, the role of the state in altering the demographic balance sheet, and the strategic response of peasant families to bring families of old designs back and urban migration and proletarianization. It is concluded that there is growing understanding that the causal relationships between population growth and economic development do not clearly support universal population control. Human social organization, not the man/land ratio, shapes the consequences of population growth. The implications for the Malthusian vs. Marxian debate for developing countries are that the resources/population imbalance needs to consider more carefully the human organizational factors. Mao's notions that a revolutionary transformation of the social organization of production in China would resolve overpopulation have since been rectified by opposing ideological positions: changing the basic mode of production through institutional decollectivization and checking population growth with the 1-child policy. This dilemma in rural areas translates to greater productivity and diversification with Chinese families having abundant adult labor and secured by the number of sons. It is difficult to substantiate the benefit of small families for peasants theoretically. Political rewards have been curtailed by economic declines. The peasant family has adapted by reconstituting old family forms and kin networks and by out-migration and nonagricultural employment.  相似文献   

10.
A new set of alternative socioeconomic scenarios for climate change researches—the shared socioeconomic pathways (SSPs)—includes for the first time a more comprehensive set of demographic conditions on population, urbanization, and education as the central scenario elements, along with other aspects of society, in order to facilitate better analyses of challenges to climate change mitigation and adaptation. However, it also raises a new question about the internal consistency of assumptions on different demographic and economic trends under each SSP. This paper examines whether the interactions between the demographic and economic factors implied by the assumptions in the SSP projections are consistent with the research literature, and whether they are consistently represented in the projection results. Our analysis shows that the interactions implied by the demographic assumptions in the SSPs are generally consistent with findings from the literature, and the majority of the assumed relationships are also evident in the projected trends. It also reveals some inconsistency issues, resulting mainly from the use of inconsistent definitions of regions and limitations in our understanding of future changes in the patterns of interactions at different stages of socioeconomic development. Finally, we offer recommendations on how to improve demographic assumptions in the extended SSPs, and how to use the projections of SSP central elements in climate change research.  相似文献   

11.
This paper seeks to broaden the application of demographyto environmental studies by complementing existing macro-level approaches, which feature aggregate populations, with a micro-level approach that highlights household life cycles. I take up the case of small farm households in the Brazilian Amazon to present a theoretical framework that identifies demographic characteristics which dispose families to engage in different forms of land use as household age structures change. Empirical models show that net of theeffects of farmer background, neighborhood context, institutional context, and off-farm incomes, demographic variables indicative of the household life cycle exert significant effects on the prominence of land uses with distinct environmental ramifications. The findings not only reveal micro-level demographic factors which affect Amazon land cover, they yield implications forfuture changes in rainforest landscapes in northern Brazil, and suggest household life cycle models as an avenue for further demographic research on environmental change in Latin America and other contexts.  相似文献   

12.
Environmental Influences on Human Migration in Rural Ecuador   总被引:1,自引:0,他引:1  
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.  相似文献   

13.
This article describes and analyzes the impacts of population and demographic change on the vulnerability of communities to climate change and variability. It begins with a review of existing literature on the effects of population change on anthropogenic greenhouse gas emissions, the exposure of settlements to climate risks, and on the capacity to adapt to climate change. The article explores the relationship between population change and adaptive capacity through detailed examination of empirical findings from a study of small communities in eastern Ontario, Canada currently experiencing a combination of changes in local climatic conditions and rapid demographic change caused by in-migration of urban retirees and out-migration of young, educated people. The combination of changing demographic and climatic patterns has placed increased stress on local social networks that have long been critical to climate adaptation in that region. The case study and literature review are used to create a general typology of the relationship between population change and vulnerability that may be used as a framework for future research in this field.  相似文献   

14.
徐媛媛  孙浩  燕彬 《西北人口》2016,(5):112-118
计划生育政策实施以来,我国人口年龄结构发生了剧烈变动,农村居民消费严重不足,扩大内需成为新常态下我国经济发展的战略方向。基于2001~2013年省际面板数据,运用一步系统广义矩估计法,实证研究了西北五省农村地区人口年龄结构变动对农村居民消费的影响,结果显示:西北五省农村少儿抚养比和农村老年抚养比均与居民消费呈同向变动关系,有效地支持了生命周期假说;城镇化水平与农村居民消费则呈负向关系。  相似文献   

15.
Long-term trends in deservingness opinions and how these fluctuate in relation to changes in the economic, institutional and political contexts have not often been examined. In this paper, we address these trend questions by analyzing 22 waves of the repeated cross-sectional Cultural Change in The Netherlands (CCN, 1975–2006) survey. Our analyses show fairly stable public deservingness opinions regarding five different needy groups over the long term. Over the short term, opinions fluctuate more. Explanatory analyses show that economic and political factors, but not institutional factors, are especially influential over fluctuations in opinions. When real GDP grows, the Dutch public is more likely to consider the disabled, the elderly and social assistance beneficiaries deserving of more welfare support. In addition, when unemployment rises, the unemployed and social assistance beneficiaries are more likely to be seen as deserving of more support. Finally, when the national political climate is more leftist, most needy groups are considered to be deserving of more welfare support.  相似文献   

16.
Regarding migration, the current thinking is that certain aspects of migration have important implications for population planning. Focus here is on the role of migration and its influence on integrated development programs. Although individuals who migrate to cities are generally from the more privileged socioeconomic groups within the rural area, it is not accurate to identify them as the "cream of the rural population." Present population policies do consider the fact that 70 to 80% of the people live in rural areas, yet population policies give only lip service to migration policies. In response to a question as to whether urbanization is conducive to pro- to anti-natal tendencies in migrating families the responses varied. 1 opinion was that there is no evidence that urbanization and the natality behavior of migrating families is significantly related, while other opinions identified a relationship between anti-natal behavior and migration. Rural development and rural growth centers do seem to help alleviate population problems of rural and urban areas, but their success is very dependent on the kind of rural development programs and the extent of services provided through the growth center. The following are among the advantages to "planned migration" that can be used to strengthen population policies: 1) effective utilization of manpower; 2) balanced regional development; 3) further exploitation of natural resources; and 4) reducing the various problems in urban regions. Many do believe that international migration is a feasible solution to population problems in the global context.  相似文献   

17.
Debate over climate change focuses narrowly on the reduction of greenhouse gas emissions. A common justification for such emissions reductions is that they will lead to a reduction in the future impacts of climate on society. But research from social scientists and others who study environment–society interactions clearly indicates that the dominant factors shaping the impacts of climate on society are societal. A greater appreciation for this body of research would allow for consideration of a broader base of policy options to respond to the challenges of climate change, as well as the composition of climate research portfolios more likely to contribute useful knowledge to decision makers.  相似文献   

18.
Many believe that linking population growth to the issue of climate change will help to place family planning back into the political realm as an urgent matter of national and environmental security. Others worry, however, that focusing on the environmental impacts of demographic change places at risk the hard-fought and long-developed global consensus that individual rights and empowerment are what matters most in fostering sustainable development and stabilizing population growth. This paper focuses on United States population policy. It presents a brief historical background and summarizes the state of scientific evidence regarding the impacts of population growth on climate change. It then analyzes some of the underlying ethical issues involved in advancing an advocacy argument around increasing family planning as a way to slow population growth and mitigating climate change. Finally, it recommends a way in which advocates can frame the connections between population growth and climate change in a just and ethical manner.  相似文献   

19.
Resource regimes are complex social–ecological systems that operate at multiple levels. Using data from two distinct cultural and environmental contexts (Mexico and India), this paper looks at the susceptibility and response of such regimes to rural out-migration. As a driver of demographic and cultural change, out-migration impacts both the practices and institutional arrangements that define territorial resource use and management. The research shows that critical yet poorly recognised shifts in migration dynamics can increase the pressures felt locally and serve to reduce the effectiveness of institutional adaptations at the community level. From an environmental perspective, the research adds to the body of work examining the impacts of rural depopulation on land and seascapes and associated biological diversity. We question the assumption that rural–urban migration necessarily simulates ecosystem recovery and aids conservation. This finding is timely as funding agencies and government programs show belated interest in the consequences of out-migration for environmental management, resource use and rural livelihoods in tropical country settings.  相似文献   

20.
As progress is made in understanding the dynamics of land-use and land-cover change (LUCC), arguments that view population pressure as one of the major factors affecting forest destruction continue to be framed. Following the advances in the field of population-environment studies, this paper contends that a full account of the complex web of drivers involved in tropical deforestation needs to go beyond demographics per se. This paper examines the contribution of the ??population factor?? as a cause of deforestation in Machadinho D??Oeste, Rond?nia, Brazilian Amazonia, an area with significant small-scale farming. Conceptually, the paper shows that socioeconomic status and mediating factors (i.e., education, managerial skills, previous rural experience, integration into the local, and regional contexts), and attitudes and behaviors toward the land parcel development mediate migrants?? relationships with the local environment. The analysis combines multiple data sources (i.e., demographic census, household survey, land-cover maps, in-depth interviews) and analytical approaches (i.e., fuzzy sets statistics, remote-sensing/GIS analysis, interpretivist qualitative assessment) to examine the complex interrelationships between LUCC and human population.  相似文献   

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