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1.
Debates over the merits and demerits of globalisation for health are increasingly polarised. Conclusions range from globalisation being essentially positive for health, albeit with a need to smooth out some rough edges, to one of utter condemnation, with adverse effects on the majority of the world's population. Anyone wading into this debate is immediately confronted by seemingly irreconcilable differences in ideology, opinion and interests. Both camps agree that global changes are occurring, and with them many of the determinants of population health status. While some skepticism persists about whether “globalisation” has value beyond being a fashionable buzzword, most agree that we need better understanding of these changes. Two difficult questions arise: (i) What are the health impacts of these changes; and (ii) how can we respond more effectively to them? To move beyond the stand-offs that have already formed within the health community, this paper reviews the main empirical evidence that currently exists, summarises key points of debate that remain, and suggests some ways forward for the research and policy communities. In particular, there is need for an informed and inclusive debate about the positive and negative health consequences of globalisation.  相似文献   

2.
In 2000, the World population was 6.2 billion people; it reached 7 billion in 2012 and is expected to reach 9.5 billion (±0.4) in 2050 and 11 billion (±1.5) in 2100, according to the 2012 UN projections (Gerland et al. in Science 346:234–237, 2014). The trend after 2100 is still one of the global demographic growths, but after 2060, Africa is the only continent where the population would still increase. The amount of water consumed annually to produce the food necessary to meet the needs of the populations varies greatly between countries, from about 600 to 2500 m3/year per capita (Zimmer in L’empreinte eau. Les faces cachées d’une ressource vitale. Charles Léopold Meyer, Paris, 2013), depending on their wealth, their food habits, and the percentage of food waste they generate (on average, 30 % of the food produced is wasted). In 2000, the total food production was on the order of 3300 million tons (in cereal equivalents). In 2014, it is estimated that about 0.8 billion inhabitants of the planet suffer from hunger (FAO in World agriculture: towards 2030–2050. FAO, Rome, 2014. http://www.fao.org/docrep/004/Y3557E/y3557e00.HTM) and do not get the nutrition they need to be in good health or, in the case of children, to grow properly (both physically and intellectually). This food deficit was on the order of 40 million tons of cereal equivalents in 2014. The number of inhabitants with a food deficit was about 0.85 billion before the 2008 crisis and was decreasing annually, but it increased abruptly after 2008 up to 1 billion inhabitants and is slowly decreasing now. Assuming a World average water consumption for food of 1300 m3/year per capita in 2000, 1400 m3/year in 2050, and 1500 m3/year in 2100, a volume of water of around 8200 km3/year was needed in 2000, 13,000 km3/year will be needed in 2050, and 16,500 km3/year in 2100 (Marsily in L’eau, un trésor en partage. Dunod, Paris, 2009). Can bioenergy be added to food production? Will that much water be available on Earth, and where will it come from? Is climate change going to modify the answers to these questions? Can severe droughts occur? Can there be conflicts related to a food deficit? Some preliminary answers and scenarios for food production will be given in this paper from a hydrologist’s viewpoint.  相似文献   

3.
Recent advances in pollution control and monitoring technologies, improved analytical capability, changes in government priorities and results of scientific studies have substantially changed our views and perceptions towards marine pollution in the last two decades. Globally, the problems caused by eutrophication, water borne pathogens and xenobiotic compounds are likely to be exacerbated and pose significant ecological and/or public health risks in the coming years, especially in developing countries. The large amount of anthropogenic input of nutrients has caused major changes in the structure and function of phytoplankton, zooplankton, benthic and fish communities over large areas, and such a trend is likely to continue in many coastal waters. Escalated public health risks associated with the increases in frequency and severity of toxic algal blooms are also of growing concern. Reduction of nutrient input through changes in land-use and farming practises, and the development of cost-effective methods for nutrient removal are required. Water borne pathogens affect large numbers of people through consumption of contaminated seafood and direct contact with contaminated water, and such problems are much more serious in developing countries. Current techniques in monitoring bacterial indicators in water and shellfish have clear limitations and cannot afford adequate protection to safeguard public health. Emerging molecular techniques, such as multiplex PCR and specific gene probes, are likely to provide new and cost effective tools for monitoring water borne pathogens in the coming years. Nowadays, xenobiotic compounds can be found almost everywhere in any marine ecosystems. Although these compounds normally occur at very low concentrations and their effects are not well understood, there is growing concern about the chronic exposure and bioconcentration/biomagnification of xenobiotic compounds. In particular, endocrine disrupters which may cause reproductive dysfunction and threaten species survival, are of growing concern. At present, most of our knowledge on toxic effects of xenobiotic compounds is derived from short-term exposure of a single species to high (environmentally unrealistic) and uniform concentrations under laboratory conditions. Data so derived are largely inadequate in predicting ecological effects in the field, in which multi-species are being exposed to varying, low concentrations under an interacting and complex environment. NOEC and LOEC for population/community/ecosystem, as well as the time required for population/community/ecosystems to recover after toxicant insult, are poorly known. These important topics will become the major endeavours for ecotoxicologists in the years to come.  相似文献   

4.
The mappings of poverty and food insecurity were carried out for the rural districts of the four riparian countries (Botswana, Mozambique, South Africa and Zimbabwe) of the Limpopo river basin using the results of national surveys that were conducted between 2003 and 2013. The analysis shows lower range of food insecure persons (0–40%) than poverty stricken persons (0–95%) that is attributable to enhanced government and non-government food safety networks in the basin countries, the dynamic and transitory nature of food insecurity which depends on the timings of the surveys in relation to harvests, markets and food prices, and the limited dimension of food insecurity in relation to poverty which tends to be a more structural and pervasive socio-economic condition. The usefulness of this study in influencing policies and strategies targeted at alleviating poverty and improving rural livelihoods lies with using food insecurity mappings to address short-term socio-economic conditions and poverty mappings to address more structural and long-term deprivations. Using the poverty line of $1.25/day per person (2008–2013) in the basin, Zimbabwe had the highest percentage of 68.7% of its rural population classified as poor, followed by Mozambique with 68.2%, South Africa with 56.1% and Botswana with 20%. While average poverty reduction of 6.4% was observed between 2003 and 2009 in Botswana, its population growth of 20.1% indicated no real poverty reduction. Similar observations are made about Mozambique and Zimbabwe where population growth outstripped poverty reductions. In contrast, both average poverty levels and population increased by 4.3% and 11%, respectively, in South Africa from 2007 to 2010. While areas of high food insecurity and poverty consistently coincide with low water availability, it does not indicate a simple cause–effect relationship between water, poverty and food insecurity. With limited water resources, rural folks in the basin require stronger institutions, increased investments and support to enable them generate sufficient income from their rain-fed farming livelihood to break out of the poverty cycle.  相似文献   

5.
This paper introduces economic concepts and theory pertaining to public policy issues and concerns about pollution in marine environments. Many of these concepts and theories are unfamiliar to individuals and professionals outside the field of economics, such as biologists, ecologists, environmental lawyers, and even public policymakers. Yet many of these individuals observe economics in action, often for the first time, within a public policy arena. Exposure and a better understanding of the concepts and ideas in economics that are particularly relevant for public policies can help to achieve efficiencies in the form of better designed policies, and help to bridge communications gaps across other professions and the economics profession.  相似文献   

6.
中国水库放养鱼的种类、食性以及可利用的天然饵料生物决定了半精养渔业是水库渔业的主要模式。水库半精养有中、小型水库、水库库汊、网拦、网围、网箱养鱼等多种形式。其产量与肥料、饲料的投入有直接关系。最大限度地利用天然饵料,并辅以补充性人工饲料,可实现高产高效。本文以水库鱼类的营养和饲料利用为基础,论述半精养水库渔业的理论和实用技术,并提出尚须研究的问题,以推进半精养水库渔业的发展。  相似文献   

7.
The time-dependent three-dimensional distribution of a population of Karenia brevis is explored through the use of an Eulerian model. The model combines a previously developed physiologically based behavioral model of these dinoflagellates with a simple model for a three-dimensional wind driven flow field over a variable-depth continental shelf. The behavioral model is simplified from that used in previous applications and sigma coordinates are utilized in the model. Model results indicate that even for the relatively weak wind driven currents used in our simulation a non-quantized population can develop into two spatially distinct quantized populations in a period as short as 1 day where, for present purposes, a quantized population is one in which all cells are at the same stage of the cell cycle.  相似文献   

8.
HAB occurrence is becoming more frequent and problematic in marine recreational waters. However, the exploitation of the coastal area for recreational use is promoting the necessary conditions for the HAB increase. In terms of the harmful effects, we can consider two types of causative organism: the toxic producers and the high-biomass producers. Toxic events can be produced by a very low concentration of the causative organism. This characteristic implies a difficulty for the monitoring programs in relation to human health. It is important to point out in the context of human health and HAB events, that in some coastal regions (e.g. the Mediterranean basin) HABs are an emerging problem. In these regions, the local population and visitors may face a health risk that is difficult to measure. The monitoring of toxic species has mainly been associated -with shellfish farming. However, the risk of intoxication could become even greater in areas not subject to legislation of aquaculture activities.  相似文献   

9.
There are fundamental links between population health, environment and economic development. The ultimate goal of economic development is to improve the quality of human life and increase people's longevity. This goal cannot be achieved without a clean and prosperous Earth. There has been increasing evidence showing that the expansion of economic activities can have significant impacts on the environment and can cause large-scale and sometimes irreversible environmental changes. It is beyond reasonable doubt that these changes will have serious public health consequences. How to tackle these issues is a unprecedented challenge to scientists and policy-makers. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

10.
Cities based on coal resources have increasingly important social and economic roles in China. Their strategies for sustainable development, however, urgently need to be improved, which represents a huge challenge. Most observers believe that the continued progress of these cities relies on the optimization of scientific adaptive management in which social, economic, and ecological factors are incorporated. A systems perspective that combines policies, management priorities, and long-term policy impacts needs to be applied. To date, however, such an approach has not been adopted, which means it is difficult to implement adaptive management at the regional scale. In this study, we used various situations to develop a multiple adaptive scenario system dynamics model. We then simulated a range of policy scenarios, with Ordos in the Inner Mongolia Autonomous Region as a case study. Simulation results showed that the current strategy is not sustainable and predicted that the system would exceed the environmental capacity, with risks of resource exhaustion and urban decline in 2025–2035. Five critical policy variables, including the urban population carrying capacity, rates of water consumption and water recycling, and expansion of urban land cover, were identified during sensitivity analysis. We developed and compared six socio-economic scenarios. The urban area, represented by the urban population density, seemed to transition through five different stages, namely natural growth, rapid growth, stable oscillation, fading, and rebalancing. Our scenarios suggested that different policies had different roles through each stage. The water use efficiency management policy had a comprehensive far-reaching influence on the system behavior; land urbanization management functions dominated at the start, and population capacity management was a major control in the mid-term. Our results showed that the water recycling policy and the urban population carrying capacity were extremely important, and both should be reinforced and evaluated by the local governments.  相似文献   

11.
Many cultured pearl farms are located in areas of the Pacific that have thriving, highly diverse fish communities but the impacts of farming on these communities are poorly understood. We studied the effects of pearl oyster farming on shore fish abundance and diversity in the lagoon of Ahe, French Polynesia by adapting roving diver census methods to the coral reef bommies of the lagoon and compared 16 sites with high pearl farming impact to others with no direct impact. Pearl farming has a slightly positive effect on reef fish abundance (N) and no significant impact on fish diversity (H) or community composition. This is important when considering the ecological sustainability of pearl farming in French Polynesia and suggests that a potential synergy between pearl farms and marine conservation should be further explored.  相似文献   

12.
As the joint project of IGBP (International Geo-sphere-Biosphere Programme) and IHDP (Interna-tional Human Dimensions Programme on Global En-vironmental Change), LUCC (Land Use/Land Cover Change) has been the focus of geographic studies, not only because it is one of the main contents of global environmental change studies, the linkage between physical and human sciences[1], but also because it has a close relationship with some elements’ cycles inside terrestrial ecosystem, such as…  相似文献   

13.
Understanding the spread of any disease is a highly complex and interdisciplinary exercise as biological, social, geographic, economic, and medical factors may shape the way a disease moves through a population and options for its eventual control or eradication. Disease spread poses a serious threat in animal and plant health and has implications for ecosystem functioning and species extinctions as well as implications in society through food security and potential disease spread in humans. Space–time epidemiology is based on the concept that various characteristics of the pathogenic agents and the environment interact in order to alter the probability of disease occurrence and form temporal or spatial patterns. Epidemiology aims to identify these patterns and factors, to assess the relevant uncertainty sources, and to describe disease in the population. Thus disease spread at the population level differs from the approach traditionally taken by veterinary practitioners that are principally concerned with the health status of the individual. Patterns of disease occurrence provide insights into which factors may be affecting the health of the population, through investigating which individuals are affected, where are these individuals located and when did they become infected. With the rapid development of smart sensors, social networks, as well as digital maps and remotely-sensed imagery spatio-temporal data are more ubiquitous and richer than ever before. The availability of such large datasets (big data) poses great challenges in data analysis. In addition, increased availability of computing power facilitates the use of computationally-intensive methods for the analysis of such data. Thus new methods as well as case studies are needed to understand veterinary and ecological epidemiology. A special issue aimed to address this topic.  相似文献   

14.
Littoral rotifers and cladocerans feed on bacteria, phytoplankton, and detritus. In comparison to planktonic organisms their species diversity is high, yet little is known about their biology. In this study we present data on the functional response of the cladocerans Macrothrix triserialis and Alona rectangula, and the rotifer Brachionus macracanthus to different levels of the alga Chlorella vulgaris. Based on the incipient limiting level, we chose the food concentration and tested the population growth on four types of diets for three cladoceran species — Macrothrix triserialis, Alona rectangula, and Chydorus sphaericus — and three rotifer species — Brachionus macracanthus, Lecane quadridentata, and Platyias quadricornis. We studied growth rates of each of these species on diets of live Chlorella vulgaris, heat‐killed Chlorella vulgaris, baker's yeast (Saccharomyces cerevisiae), and field collected detritus. The incipient limiting level was around 0.9 · 106 cells mL?1 of Chlorella for the tested zooplankton species. The population growth patterns showed that, in general, the cladocerans took 25…50 d to reach their peak population densities, which ranged from 10…75 ind. mL?11. Among the rotifers L. quadridentata and B. macracanthus had equally high growth rates on live and heat‐killed forms of C. vulgaris while P. quadricornis grew best on detritus. The growth rates ranged from 0.03…0.21 d?1. The similarities and differences between littoral and planktonic organisms in relation to food type and availability have been discussed.  相似文献   

15.
Consumers world-wide are driving changes in the agriculture and food sector. Rising consumer income, changing demographics and lifestyles, and shifting preferences due to new information about the links between diet and health all contribute to new demands for foods. At the same time, technological changes in production, processing and distribution, growth in large-scale retailing, and changes in product availability, as well as expansion of trade world wide, have contributed to a rapidly changing market for food products. Changes in seafood consumption reflect these changes. The changes in consumer consumption patterns, new technologies and trade in product offer both expanded markets as well as new challenges to consumer exposure to food-borne risks. The strict quality control requirements of retail brokers, growth of private labels, and development of value-protecting marketing channels have become increasingly important in food markets. This paper addresses major trends that affect seafood consumption and the market for seafood products and the implications of these changes for consumer risk exposure to food safety hazards. The current economic environment highlights similarities and differences between the developed and developing countries, as well as diversity worldwide in consumption of seafood. Within this context, four major trends affect consumer consumption of foods, including seafood and fish products today: rising income; changing demographics; changing markets for food; and an increasingly global market for food products. Changes in consumer risk exposure to food safety problems are addressed in the context of these trends.  相似文献   

16.
The large-scale flux of nitrogen and phosphorus in modern society is coupled to the exponentially growing world population. During the last three decades there has been a several-fold growth in use of nitrogen (N) and phosphorus (P), for example, for agriculture production, in chemical products such as in detergents, and as food additives. Feeding a growing population means increased human nutrient excretion.

The mobility of N differs from that of P. For the easily mobile nitrate ion, river exports are positively correlated to the size of local human populations. P on the other hand is fixed in different systems, at least temporarily. Modern agro-ecosystems accumulate about 60% of the annual input of P. The Stockholm region representing an urban ecosystem served by dephosphatation in sewage, accumulated about 80% of imported P during 1990. With increasing accumulation there is an apparent risk for increasing non-point source pollution.

In some shallow recipient lakes the sediments have been saturated with P. Even after the reduction of external loading these lakes are exporting more P than they are importing. Lakes normally are traps for P.

In order to prevent damage to natural resources and to stop the large-scale flux of nutrients from land to water, the world population growth rate must be decreased and a number of measures taken: agricultural structures must be changed including new concepts for the use of fertilizers; new municipal sewage treatment processes must be developed permitting high-degree recycling of nutrients; unnecessary use of nutrients must be stopped, for example, in detergents and by reducing nutrient additives in food and drinks. Cola drinks, for example, contain 180 mg P l−1, a concentration about 350 times higher than that of the effluent (0.5 mg P l−1) from modern sewage treatment plants operating with dephosphatation. Financial resources and effort are required to stop large-scale eutrophication of marine waters.  相似文献   


17.
Emerging infectious diseases continue to place a strain on the welfare of the population by decreasing the population’s general health and increasing the burden on public health infrastructure. This paper addresses these issues through the development of a computational framework for modeling and simulating infectious disease outbreaks in a specific geographic region facilitating the quantification of public health policy decisions. Effectively modeling and simulating past epidemics to project current or future disease outbreaks will lead to improved control and intervention policies and disaster preparedness. In this paper, we introduce a computational framework that brings together spatio–temporal geography and population demographics with specific disease pathology in a novel simulation paradigm termed, global stochastic field simulation (GSFS). The primary aim of this simulation paradigm is to facilitate intelligent what-if-analysis in the event of health crisis, such as an influenza pandemic. The dynamics of any epidemic are intrinsically related to a region’s spatio–temporal characteristics and demographic composition and as such, must be considered when developing infectious disease control and intervention strategies. Similarly, comparison of past and current epidemics must include demographic changes into any effective public health policy for control and intervention strategies. GSFS is a hybrid approach to modeling, implicitly combining agent-based modeling with the cellular automata paradigm. Specifically, GSFS is a computational framework that will facilitate the effective identification of risk groups in the population and determine adequate points of control, leading to more effective surveillance and control of infectious diseases epidemics. The analysis of past disease outbreaks in a given population and the projection of current or future epidemics constitutes a significant challenge to Public Health. The corresponding design of computational models and the simulation that facilitates epidemiologists’ understanding of the manifestation of diseases represents a challenge to computer and mathematical sciences.  相似文献   

18.
运用变分原理,我们得到了最小地震波辐射能量约束准则并用于研究震源的物理过程.通过研究1995年ML4.1河北沙城地震序列主震和余震的动力学过程,可知主震和余震震源的动态破裂过程明显不同;ML4.1主震的破裂速度与瑞利波速相近,约为剪切波速度的0.89倍;而28个余震的破裂速度远远小于剪切波速度,大约是剪切波速度的0.05到0.55倍.根据裂纹扩展模型,计算得到其余震的地震波辐射效率多在10%以下,这也说明了余震的地震效率较低.我们认为余震震源的动态破裂过程应与断层内部新生裂纹的扩展有关,而非简单的岩体间的相对滑动.余震震源的动态破裂传播与破裂能占主导地位的小地震有关.这些小震所带来的破裂能也导致了断层的进一步扩展.在对该地震序列的研究中,我们发现主震与余震的震源破裂过程在能量分配上有着本质的区别.因此当地震断层尺度相当小时,破裂能的贡献不能忽略,它的大小将显著地影响地震波辐射能的大小.  相似文献   

19.
In the Thau lagoon, despite there being no phosphate limitation policy, the annual mean phosphate concentrations decreased by 90% between 1971 and 1994. The present study indicates a relationship between the decrease of phosphate concentrations and changes in urban, industrial and agricultural activities within the catchment generating phosphorus (P) inputs; and shellfish farming leading to phosphorus storage and export. The relationship (tonnes of P) is: P-PO(4)(3-) in the lagoon waters=1.0124 anthropogenic phosphorus balance--47.62 (r(2) = 0.824, p < 0.000). As population growth is expected in coastal zones, sustainable development requires the need for addressing the role played by human activities and the multi-scale regulation of them. As an element of integrated coastal zone management, the present study provides a regional scale analysis of these aspects.  相似文献   

20.
Two empirical models are presented to elucidate the mechanisms driving reductions in the mercury concentration of southern bluefin tuna (SBT) during culture. Model 1 predicts temporal fluctuations in mercury concentration in response to growth dilution. Model 2 predicts the combined effects of growth dilution and linear mercury accumulation. Model 2 was found to be the more accurate model. Over a typical farming period of 136 days, growth dilution resulted in a reduction in mean mercury concentration of SBT edible tissues from 0.51 mg/kg down to 0.33 mg/kg. Extended culture beyond 136 days resulted in an increase in mercury concentration due to the combined effects of mercury accumulation and seasonal lipid depletion. Results indicate that under current industry practice, cultured SBT can be consumed twice as frequently as that of wild caught SBT while maintaining total dietary mercury intake below national recommendations.  相似文献   

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