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1.
Age-specific secular trend patterns for children in industrialized world regions have a regular pattern, beginning low at age 6 and increasing to a maximum at age 10 to 14, then declining. While magnitude differs, the patterns are ordinarily parallel, especially in the female samples. However, age-specific secular trend values for children from developing regions, or from areas of industrialized countries not benefitting substantially from development, are irregular in pattern and magnitude. Consequently, it is difficult to predict age at maximal secular change. We suggest that fluctuating environmental circumstances in these developing countries influence growth and, hence, the pattern of secular trend. As more stable environmental conditions relating to growth are present in the industrialized countries, this leads to more stable patterns of growth and age-specific patterns of secular change.  相似文献   

2.
The livestock sector globally is highly dynamic. In developing countries, it is evolving in response to rapidly increasing demand for livestock products. In developed countries, demand for livestock products is stagnating, while many production systems are increasing their efficiency and environmental sustainability. Historical changes in the demand for livestock products have been largely driven by human population growth, income growth and urbanization and the production response in different livestock systems has been associated with science and technology as well as increases in animal numbers. In the future, production will increasingly be affected by competition for natural resources, particularly land and water, competition between food and feed and by the need to operate in a carbon-constrained economy. Developments in breeding, nutrition and animal health will continue to contribute to increasing potential production and further efficiency and genetic gains. Livestock production is likely to be increasingly affected by carbon constraints and environmental and animal welfare legislation. Demand for livestock products in the future could be heavily moderated by socio-economic factors such as human health concerns and changing socio-cultural values. There is considerable uncertainty as to how these factors will play out in different regions of the world in the coming decades.  相似文献   

3.
The global food system is a major energy user and a relevant contributor to climate change. To date, the literature on the energy profile of food systems addresses individual countries and/or food products, and therefore a comparable assessment across regions is still missing. This paper uses a global multi‐regional environmentally extended input–output database in combination with newly constructed net energy‐use accounts to provide a production and consumption‐based stock‐take of energy use in the food system across different world regions for the period 2000–2015. Overall, the ratio between energy use in the food system and the economy is slowly decreasing. Likewise, the absolute values point toward a relative decoupling between energy use and food production, as well as to relevant differences in energy types, users, and consumption patterns across world regions. The use of (inefficient) traditional biomass for cooking substantially reduces the expected gap between per capita figures in high‐ and low‐income countries. The variety of energy profiles and the higher exposure to energy security issues compared to the total economy in some regions suggests that interventions in the system should consider the geographical context. Reducing energy use and decarbonizing the supply chains of food products will require a combination of technological measures and behavioral changes in consumption patterns. Interventions should consider the effects beyond the direct effects on energy use, because changing production and consumption patterns in the food system can lead to positive spillovers in the social and environmental dimensions outlined in the Sustainable Development Goals.  相似文献   

4.
Iceland and Trinidad and Tobago are small open, high‐income island economies with very specific resource‐use patterns. This article presents a material flow analysis (MFA) for the two countries covering a time period of nearly five decades. Both countries have a narrow domestic resource base, their economy being largely based on the exploitation of one or two key resources for export production. In the case of Trinidad and Tobago, the physical economy is dominated by oil and natural gas extraction and petrochemical industries, whereas Iceland's economy for centuries has been based on fisheries. More recently, abundant hydropower and geothermal heat were the basis for the establishment of large export‐oriented metal processing industries, which fully depend on imported raw materials and make use of domestic renewable electricity. Both countries are highly dependent on these natural resources and vulnerable to overexploitation and price developments. We show how the export‐oriented industries lead to high and growing levels of per capita material and energy use and carbon dioxide emissions resulting from large amounts of processing wastes and energy consumption in production processes. The example of small open economies with an industrial production system focused on few, but abundant, key resources and of comparatively low complexity provides interesting insights of how resource endowment paired with availability or absence of infrastructure and specific institutional arrangements drives domestic resource‐use patterns. This also contributes to a better understanding and interpretation of MFA indicators, such as domestic material consumption.  相似文献   

5.
Recent research has found an inverted U relationship between freshwater use and income after controlling for freshwater availability, the structure of the economy, and several policy variables. This suggests that the intensity of freshwater use must be declining with income growth. This hypothesis is tested by developing a simple, informal model of the determinants of freshwater-use intensities across countries and over time. Results suggest that water-use intensity declines across the entire range of per capita incomes extant in the world today. They also show that the relationship between intensity of use and income is mediated by an economy's natural water endowment, the structure of the economy, and government policies. Four policies, in particular, affect the water-use intensity of economies. Open trade policies and tough environmental regulatory policies lower water use intensities, and narrowly defined food self-sufficiency policies and socialist development policies increase water-use intensities. These findings suggest that those interested in water, water scarcity, and water policy need to extend beyond simple extrapolations of past consumption patterns and narrowly focused water policies (such as water pricing) if they want to improve water management practices.  相似文献   

6.
The degree to which regions can produce desirable socioeconomic and environmental outcomes while consuming fewer resources and producing fewer undesirable outcomes can be viewed as measure of productivity. Economists have frequently used Malmquist Indices to evaluate intertemporal productivity changes of economic entities, such as firms and countries. We use Malmquist Indices to evaluate the predicted environmental performance of the rapidly growing Charlotte, NC, metropolitan area under alternative future land use scenarios. These scenarios project population, urban development, and environmental impacts from the base year 2000 to the year 2030 within the region's 184 watersheds. The first scenario is based on a continuation of current growth trends and patterns (“Business as Usual” or BAU). The second scenario uses compact “smart growth” development (“Compact Centers” or CC). We use data envelopment analysis (DEA) to estimate Malmquist Indices, which in this case, combine multiple variables into a single indicator that measures the relative impact of different development patterns on the consumption of natural resources. The results predict that the CC scenario maintains the region's current productivity, while the BAU scenario results in lower productivity. As watersheds in the study area are about the same size, weighting the results by area makes little difference. Watershed populations, however, vary greatly, and our results predict that watersheds with higher population densities also have higher Malmquist Index efficiencies. The model also predicts that low population watersheds will benefit more from the CC scenario. While the application of these analytical techniques in this case study is limited in scope, the results demonstrate that the Malmquist Index is a potentially powerful tool for interdisciplinary environmental impact analysis  相似文献   

7.
Rapid population growth continues in the least developed countries. The revisionist case that rapid population could be overcome by technology, that population density was advantageous, that capital shallowing is not a vital concern and that empirical investigations had not proved a correlation between high population growth and low per capita income was both empirically and theoretically flawed. In the modern world, population density does not play the role it did in nineteenth-century Europe and rates of growth in some of today''s least developed nations are four times than those in nineteenth-century Europe, and without major accumulation of capital per capita, no major economy has or is likely to make the low- to middle-income transition. Though not sufficient, capital accumulation for growth is absolutely essential to economic growth. While there are good reasons for objecting to the enforced nature of the Chinese one-child policy, we should not underestimate the positive impact which that policy has almost certainly had and will have over the next several decades on Chinese economic performance. And a valid reticence about telling developing countries that they must contain fertility should not lead us to underestimate the severely adverse impact of high fertility rates on the economic performance and prospects of many countries in Africa and the Middle East.  相似文献   

8.
世界主要国家耕地动态变化及其影响因素   总被引:10,自引:0,他引:10  
赵文武 《生态学报》2012,32(20):6452-6462
在世界人口持续攀升、全球耕地面积不断减少的背景下,探讨世界主要国家耕地变化其影响因素,对于分析预测未来世界耕地变化趋势、研究世界粮食安全具有积极意义。选择2050年人口过亿的17个国家和耕地面积排名前10的国家为研究对象,在分析1961—2007年耕地总量变化、人均耕地变化的基础上,探讨了耕地变化影响因素。研究结果表明,从20世纪60年代到2007年间的不同时期内,有越来越多的国家表现出耕地减少趋势,而人均耕地面积减少的国家个数高达90%以上。满足人口消费需求、城市化与经济发展是大多数国家耕地总量变化的主要动力;而人口快速增长、城市化则是导致许多国家人均耕地显著减少的重要原因。  相似文献   

9.
Epizootics (nonhuman animal disease epidemics) can have detrimental impacts on livelihoods through a complex interaction of demographic trends, food production, and animal disease. Differences in the rate of demographic shifts, including rates of population growth, economic growth, urbanization, environmental sustainability, and role of women in society, are strong driving forces that will determine to what extent food demand will be matched by food production capacity. Epizootics can negatively affect commerce and trade in all countries, and in low-income countries limited infrastructure and resources as well as competing priorities provide additional disincentive to controlling or eradicating animal diseases. Economic growth is critical to overcoming disparities among countries and is best supported by integrated animal health, public health, labor, and foreign policies. The adverse impacts of epizootics can be largely overcome through programs that support job growth along the value-added chain of food production and will require significant investments in science- (risk-) based education.  相似文献   

10.
Life history theory aims to explain the relationship between life events, recognizing that the fertility and growth schedules of organisms are dependent on environmental conditions and an organism’s ability to extract resources from its environment. Using models from life history theory, we predict life expectancy to be positively correlated with educational investments and negatively correlated with adolescent reproduction and total fertility rates. Analyses of UN data from 193 countries support these predictions and demonstrate that, although variation is evident across world regions, strong interactions exist among life expectancy, reproductive investments, and educational attainment, and these relationships occur independently of economic pressures and disease burdens. The interactions are strongest, however, in countries with a life expectancy of ≥60 years as these countries tend to have stable economies and a limited HIV/AIDS burden. These findings suggest that policies aimed at influencing education and reproductive decisions should consider environmental characteristics that drive people’s expectations about their longevity.  相似文献   

11.
In this article, the development of natural resource use in Finland during the period 1970-1997 is analyzed. In measuring natural resource use, the concept of total material requirement (TMR) is applied. The focus is on the linkages of resource use with the changing structures of the economy. The linkages are studied using input-output analysis.
Using input-output analysis, the TMR is further partitioned into resources used for domestic final use or for total material consumption (TMC) and total material requirement of exports (TME). The analysis shows that TMR has the problem of double accounting: if the TMRs of all countries of the world are summed, then international trade would be accounted for twice in the world TMR, once in imports and once in exports of each country.
The TMC concept does not have this kind of defect. In a small, open economy like that of Finland, where the share of foreign trade is large, the difference between the TMR and the TMC is also large. We show that by 1997, the TME comprised about half of Finland's TMR and that the growth of the TMR over the study period has been due to the TME only as the TMC has stayed rather constant.  相似文献   

12.
Contemporary humans occupy the widest range of socioeconomic environments in their evolutionary history, and this has revealed unprecedented environmentally-induced plasticity in physical growth. This plasticity also has limits, and identifying those limits can help researchers: (1) parse when population differences arise from environmental inputs or not and (2) determine when it is possible to infer socioeconomic disparities from disparities in body form. To illustrate potential limits to environmental plasticity, we analyze body mass index (BMI) and height data from 1,768,962 women and 207,341 men (20–49 y) living in households exhibiting 1000-fold variation in household wealth (51 countries, 1985–2017, 164 surveys) across four world regions—sub-Saharan Africa, South Asia, Latin America, and North Africa and the Middle East. We find that relationships of environmental inputs with both mean height and BMI bottom out at roughly 100–700 USD per capita household wealth (2011 international units, PPP), but at different basal BMIs and basal heights for different regions. The relationship with resources tops out for BMI at around 20 K–35 K USD for women, with growth potential due to environmental inputs in the range of 6.2–8.4 kg/m2. By contrast, mean BMI for men and mean height for both sexes remains sensitive to environmental inputs even at levels far above the low- and middle-income samples studied here. This suggest that further work integrating comparable data from low- and high-income samples should provide a better picture of the full range of environmental inputs on human height and BMI. We conclude by discussing how neglecting such population-specific limits to human growth can lead to erroneous inferences about population differences.  相似文献   

13.
Trends of increasing agricultural trade, increased concentration of livestock production systems, and increased human consumption of livestock products influence the distribution of nutrients across the global landscape. Phosphorus (P) represents a unique management challenge as we are rapidly depleting mineable reserves of this essential and non-renewable resource. At the same time, its overuse can lead to pollution of aquatic ecosystems. We analyzed the relative contributions of food crop, feed crop, and livestock product trade to P flows through agricultural soils for 12 countries from 1961 to 2007. Due to the intensification of agricultural production, average soil surface P balances more than tripled from 6 to 21 kg P ha−1 between 1961 and 2007 for the 12 study countries. Consequently, countries that are primarily agricultural exporters carried increased risks for water pollution or, for Argentina, reduced soil fertility due to soil P mining to support exports. In 2007, nations imported food and feed from regions with higher apparent P fertilizer use efficiencies than if those crops were produced domestically. However, this was largely because imports were sourced from regions depleting soil P resources to support export crop production. In addition, the pattern of regional specialization and intensification of production systems also reduced the potential to recycle P resources, with greater implications for livestock production than crop production. In a globalizing world, it will be increasingly important to integrate biophysical constraints of our natural resources and environmental impacts of agricultural systems into trade policy and agreements and to develop mechanisms that move us closer to more equitable management of non-renewable resources such as phosphorus.  相似文献   

14.
Economic development and growth depend on growing levels of resource use, and result in environmental impacts from large scale resource extraction and emissions of waste. In this study, we examine the resource dependency of economic activities over the past several decades for a set of countries comprising developing, emerging and mature industrialized economies. Rather than a single universal industrial development pathway, we find a diversity of economic dependencies on material use, made evident through cluster analysis. We conduct tests for relative and absolute decoupling of the economy from material use, and compare these with similar tests for decoupling from carbon emissions, both for single countries and country groupings using panel analysis. We show that, over the longer term, emerging and developing countries tend to have significantly larger material-economic coupling than mature industrialized economies (although this effect may be enhanced by trade patterns), but that the contrary is true for short-term coupling. Moreover, we demonstrate that absolute dematerialization limits economic growth rates, while the successful industrialization of developing countries inevitably requires a strong material component. Alternative development priorities are thus urgently needed both for mature and emerging economies: reducing absolute consumption levels for the former, and avoiding the trap of resource-intensive economic and human development for the latter.  相似文献   

15.
16.
What implications might synthetic biology’s potential as a wholly new method of production have for the world economy, particularly developing countries? Theories of political economy predict that synthetic biology can shift terms of trade and displace producers in developing countries. Governments, however, retain the ability to mitigate negative changes through social safety nets and to foster adaptation to some changes through research, education and investment. We consider the effects the synthetic production of otherwise naturally derived molecules are likely to have on trade and investment, particularly in developing countries. Both rubber in Malaysia and indigo dyes in India provide historical examples of natural molecules that faced market dislocations from synthetic competitors. Natural rubber was able to maintain significant market share, while natural indigo vanished from world markets. These cases demonstrate the two extremes of the impact synthetic biology might have on naturally derived products. If developing countries can cushion the pain of technological changes by providing producers support as they retool or exit, the harmful effects of synthetic biology can be mitigated while its benefits can still be captured.  相似文献   

17.
Maternal and environmental effects can profoundly influence offspring phenotypes, independent of genetic effects. Within avian broods, both the asymmetric post‐hatching environment created by hatching asynchrony and the differential maternal investment through the laying sequence have important consequences for individual nestlings in terms of the allocation of resources to body structures with different contributions to fitness. The purpose of this study was to evaluate the relative importance of post‐hatching environmental and maternal effects in generating variation in offspring phenotypes. First, an observational study showed that within blue tit, Cyanistes caeruleus, broods, late‐hatched nestlings allocated resources to tarsus development, maintained mass gain and head‐bill growth and directed resources away from the development of fourth primary feathers. Second, a hatching order manipulation experiment resulted in nestlings from first‐laid eggs hatching last, thereby allowing comparison with both late and early‐hatched nestlings. Experimental nestlings had growth patterns which were closer to late‐hatched nestlings, suggesting that within‐brood growth patterns are determined by post‐hatching environmental effects. Therefore, we conclude that post‐hatching environmental effects play an important role in generating variation in offspring phenotypes.  相似文献   

18.
赵海凤  闫昱霖  张大红 《生态学报》2015,35(4):1249-1257
首先对"低碳经济"进行了讨论,进而提出了"碳循环经济"概念;对现有碳计量进行研究,提出了相应改进计算公式:碳绩效和碳经济密度。最后,对碳责任分担进行了探讨,提出了发达国家和发展中国家"责任共担、区别对待"的碳责任担负的计算模式。  相似文献   

19.
With economic growth in many developing countries, not all are making similar progress with regard to material and environmental efficiencies. This study examines material use and CO2 emission patterns and intensities from 1971 to 2015 in a typical developing country, Pakistan, and investigates national‐level and multi‐country‐level efficiency improvements using data envelopment analysis. The results are used to derive key policy insights for a sustainable economic transition with higher resource and carbon efficiencies. Results show that material intensity has reduced by 39.1% while CO2 intensity has risen by 21.5% in the country. Pakistan, when compared with its top 10 export countries, was relatively more material and CO2 intensive. National‐level efficiency was found to be low in most of the periods due to material/energy intensive agriculture and industries, low value‐added exports, etc. Insights from the national‐level efficiency analysis indicate that surging CO2 intensities have started to decline since 2010 and the economy has greatly stabilized. Multi‐country analysis revealed that the efficiency gap between Pakistan and its developed export countries (such as the United Kingdom and France) has widened during the study period. Insights from the multi‐country analysis suggest that the economic growth and industrialization improves material and environmental efficiencies to some extent, yet these improvements are not equally distributed among all countries. As a way forward, integrated policies on sustainable resource consumption, carbon mitigation, and economic growth are necessary for accruing higher benefits from rising global trade and resource connectedness.  相似文献   

20.
Nematology on a world basis has experienced phenomenal growth during the last 25 years. Major influences responsible for this growth are discussed. Education of nematologists has been most evident in only a few developed nations. Some developing countries are now beginning to train nationals as nematologists. Research programs in developed countries are more intensive than in developing nations, largely because of available resources and priorities given to solving nematological problems. Developed nations have been able to take advantage of technological advances almost immediately, whereas in developing nations the lack of resources and constraints imposed by certain social or political conditions has made this difficult. Indications are that emphasis in training nematologists in developed countries may have reached a plateau, while in developing nations provisions for training and research are on the increase.  相似文献   

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