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Rural household demographics, livelihoods and the environment   总被引:8,自引:0,他引:8  
This paper reviews and synthesizes findings from scholarly work on linkages among rural household demographics, livelihoods and the environment. Using the livelihood approach as an organizing framework, we examine evidence on the multiple pathways linking environmental variables and the following demographic variables: fertility, migration, morbidity and mortality, and lifecycles. Although the review draws on studies from the entire developing world, we find the majority of microlevel studies have been conducted in either marginal (mountainous or arid) or frontier environments, especially Amazonia. Though the linkages are mediated by many complex and often context-specific factors, there is strong evidence that dependence on natural resources intensifies when households lose human and social capital through adult morbidity and mortality, and qualified evidence for the influence of environmental factors on household decision-making regarding fertility and migration. Two decades of research on lifecycles and land cover change at the farm level have yielded a number of insights about how households make use of different land-use and natural resource management strategies at different stages. A thread running throughout the review is the importance of managing risk through livelihood diversification, ensuring future income security, and culture-specific norms regarding appropriate and desirable activities and demographic responses. Recommendations for future research are provided.  相似文献   
2.
The period 1996-2001 has witnessed a refocusing of population growth on Sydney and Melbourne as both cities have developed significant concentrations of so-called 'new economy' jobs and taken on, to greater or lesser extents, the characteristics of global cities. The consequence of these trends, for Sydney most particularly, is population growth. This paper establishes this demographic reality by describing recent demographic trends in Sydney and possible future scenarios for Sydney's population, given differing levels of fertility, internal migration and international migration. A related future trend is also traced--that the number of households in Sydney will grow more rapidly than the population due to changes in household structure. This raises the issue of how and where these households will be accommodated, given the relative land shortage in the Sydney Statistical Division and given that there is no doubt that planners in New South Wales will be attempting to maintain and enhance Sydney's status as a global city. In sum, the paper argues that Sydney planners should be preparing for growth of around one million people in the next 20 years and a further one million in the following 30 years. To maintain that potential future residents of Sydney can be redirected to other parts of New South Wales is a vain hope.  相似文献   
3.

Fertility research in population geography is rooted in a spatial demography tradition which places emphasis on the use of quantitative methodologies to analyse, model and project fertility. As data sources have become more sophisticated and abundant some have questioned whether research within the discipline is now too data-oriented resulting in a reluctance to embrace new methods and concepts. Alternative conceptualisations of fertility and reproduction are outlined which represent a shift away from general explanation to more differentiated understandings of reproductive behaviour and favour the use of qualitative methodologies in combination or in a multi-level framework. The paper illustrates, with reference to a research project in the Kalahari of Botswana, the potential for methodological pluralism in the study of fertility.  相似文献   
4.
通过测定雷州半岛南部845个耕地土壤样品pH、有机质、全氮、有效磷、速效钾、碱解氮的含量,采用层次分析法确定各肥力评价指标权重,应用模糊数学法对该区域耕地土壤肥力进行综合评价,并利用ArcGIS 9.2软件对土壤肥力空间变异进行分析.结果表明:雷州半岛南部土壤有机质、全氮、有效磷、速效钾、碱解氮平均值分别为26.18 g/kg、1.48 g/kg 、34.63 mg/kg、158.57 mg/kg、133.17 mg/kg;土壤速效磷的变异系数最高,为103.14%,属强变异性,有机质、速效钾、碱解氮、全氮的变异系数属中等变异性,pH值的变异系数最小.土壤肥力总体水平处于中等偏低;从空间分布来看,土壤肥力中部高,东北、西南部相对较低  相似文献   
5.
Fertility research in population geography is rooted in a spatial demography tradition which places emphasis on the use of quantitative methodologies to analyse, model and project fertility. As data sources have become more sophisticated and abundant some have questioned whether research within the discipline is now too data-oriented resulting in a reluctance to embrace new methods and concepts. Alternative conceptualisations of fertility and reproduction are outlined which represent a shift away from general explanation to more differentiated understandings of reproductive behaviour and favour the use of qualitative methodologies in combination or in a multi-level framework. The paper illustrates, with reference to a research project in the Kalahari of Botswana, the potential for methodological pluralism in the study of fertility.  相似文献   
6.
Pedersen, P. O. & Rasmussen, P., 1973: Danske provinsbyers indre differentiering og differentieringen mellem danske provinsbyer. Geografisk Tidsskrift, 72, 49–56. København, September 30., 1973.

This paper analyses the inner differentiation in the three largest provincial towns in Denmark by means of a factor analysis of 25 variables characterizing the population and the housing in 40 zones, 14 in Århus (187,000 inh.), 14 in Odense (133,000 inh.), and 12 in Ålborg (123,000 inh.). The paper especially focuses on the differences in inner differentiation between the three towns.  相似文献   
7.
In the face of below replacement and still declining national fertility rates in most Western societies, the proportion of reproductively aged women having a third or higher order birth has particular demographic significance. This paper seeks to complement previous survey-based studies of the socio-economic, behavioural and motivational characteristics of individuals progressing or intending to progress from a second to a third or higher order birth by examining the spatial patterning and ecological context of such births in NSW during 1996 and, in particular, the extent to which such births are especially characteristic of socially disadvantaged regions and localities in the state. The results suggest that while there is a clear, though not overwhelming, tendency towards such a concentration there is an equally clear tendency for older women living in some of the most socially advantaged areas of the metropolitan zone to engage in higher order childbearing, thereby suggesting the operation of multiple causal pathways. In the more disadvantaged areas of the metropolitan zone religious and/or ethnically based pro-natalist value sets also appear to play a significant role. In better-off localities, however, higher order reproduction would seem to reflect the greater choices - and resources - available to women, whether in or out of the labour force. Because ecological analysis cannot provide precise answers to behavioural questions and because only higher order births to women in current relationships have been taken into account in this study, further research, employing a variety of methodologies, operating at a variety of scales and drawing on alternative data sets would seem desirable if such questions are to be more fully elucidated and their policy implications better understood.  相似文献   
8.
Using 40 rounds of Demographic and Health Survey data from 18 sub-Saharan African countries, linked to high-resolution historical climate records, we analyze the relationship between climatic variability and fertility goals among reproductive-aged women. We find that, overall, women exposed to above-average temperatures report lower ideal family size and reduced probability of desiring a first or additional child. Results indicate that exposure to precipitation anomalies during the 12 months prior to the DHS survey is associated with a significant reduction in ideal family size, but longer 60-month spells of above-average precipitation are associated with increases in ideal family size. Effects of unusual precipitation are null for women’s fertility preferences at both shorter- and longer-term periods. Additional analyses show that this association varies across sub-populations defined by parity, education, residence in rural or urban areas, and region. In general, our results suggest that women exposed to adverse environmental conditions—namely abnormally hot or dry spells—will reduce their ideal family size and their preferences for having another child. In some cases, however, fertility goals may also decline during spells of favorable environmental conditions, possibly due to increased labor demands among women and their spouses. One implication of the observed links between climate variability and reproductive goals is that policymakers concerned with climate adaptation should work to ensure women have access to the necessary family planning resources needed to realize dynamic reproductive goals in a changing climate.  相似文献   
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10.
为深入了解北热带海拔梯度各山地土壤带及典型土地利用类型(次生林、香蕉园、橡胶林)土壤有机质(SOM)、综合肥力(SIF)分布特征,以云南省金平县蝴蝶谷地区为例,区分表层(0~20 cm)和亚表层(20~40 cm),测定SOM、pH、全氮、全磷、全钾和速效氮磷钾,采用修正内梅罗指数法评价SIF,分析限制SIF的关键因素。结果表明,研究区海拔与SOM、SIF呈显著正相关,6个山地土壤带表层和亚表层SOM、SIF排序为棕壤带>黄棕壤带>黄壤带>红壤带>赤红壤带>砖红壤带(P<0.05)。无论表层还是亚表层,SOM和SIF均以次生林最大,香蕉园次之,橡胶林最小,次生林SOM显著大于香蕉园和橡胶林(P<0.05),SIF则无显著差异。随着海拔升高,限制SIF的因素由速效氮、速效磷转变为速效磷和速效钾,且pH的限制逐渐加强,而维持和限制低海拔不同土地利用类型SIF的因素与同海拔段内自然土壤基本一致。未来山地开发利用过程中低海拔区域应该注重补充氮肥和磷肥,中高海拔区域注重补充磷肥和钾肥,同时调节适宜的pH更有助于土壤养分释放和植物吸收利用。综上,海拔梯度和...  相似文献   
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