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1.
The nutritional status of under-five children is a sensitive sign of a country's health status as well as economic condition. This study investigated the differential impact of some demographic, socioeconomic, environmental and health-related factors on the nutritional status among under-five children in Bangladesh using Bangladesh Demographic and Health Survey 2007 data. Two-level random intercept binary logistic regression models were used to identify the determinants of under-five malnutrition. The analyses revealed that 16% of the children were severely stunted and 25% were moderately stunted. Among the children under five years of age 3% were severely wasted and 14% were moderately wasted. Furthermore, 11% of the children were severely underweight and 28% were moderately underweight. The main contributing factors for under-five malnutrition were found to be child's age, mother's education, father's education, father's occupation, family wealth index, currently breast-feeding, place of delivery and division. Significant community-level variations were found in the analyses.  相似文献   

2.
This study seeks to understand children''s perceptions of their present and future environments in the highly biodiverse and rapidly changing landscapes of Kalimantan, Indonesian Borneo. We analyzed drawings by children (target age 10–15 years) from 22 villages, which show how children perceive the present conditions of forests and wildlife surrounding their villages and how they expect conditions to change over the next 15 years. Analyses of picture elements and their relationships to current landscape variables indicate that children have a sophisticated understanding of their environment and how different environmental factors interact, either positively or negatively. Children appear to have landscape-dependent environmental perceptions, showing awareness of past environmental conditions and many aspects of recent trends, and translating these into predictions for future environmental conditions. The further removed their present landscape is from the originally forested one, the more environmental change they expect in the future, particularly declines in forest cover, rivers, animal diversity and increases in temperature and natural disasters. This suggests that loss of past perceptions and associated “shifting environmental baselines” do not feature strongly among children on Borneo, at least not for the perceptions we investigated here. Our findings that children have negative expectations of their future environmental conditions have important political implications. More than other generations, children have a stake in ensuring that future environmental conditions support their long-term well-being. Understanding what drives environmental views among children, and how they consider trade-offs between economic development and social and environmental change, should inform optimal policies on land use. Our study illuminates part of the complex interplay between perceptions of land cover and land use change. Capturing the views of children through artistic expressions provides a potentially powerful tool to influence public and political opinions, as well as a valuable approach for developing localized education and nature conservation programs.  相似文献   

3.
Factors expected to change concurrently with forest loss—such as economic activity and air pollution—shape human health in different ways, making it difficult to ex ante predict the net impact of deforestation. This paper investigates the infant mortality effects of prenatal exposure to high biomass forest loss in Indonesia, a country with rich forest reserves increasingly being subjected to high levels of deforestation. Indonesia officially bans clearing in areas with high biomass natural forests (referred to henceforth as ‘protected forests’), yet these forests face illegal logging. The analysis uses a fixed effects approach, essentially tracking how mortality responds to protected forest cover changes over time within districts. Results suggest that protected forest loss favors survival among all infants. However, there is variation in the protected forest loss-infant mortality relationship by pregnancy order or gravidity—while children born from women’s higher order pregnancies are less likely to die when exposed to deforestation, children born from first pregnancies experience an increase in their risk of death. Potential mechanisms such as overall air pollution, economic activity and perinatal health care do not appear to explain the gravidity-specific effects of deforestation in protected areas. However, the observed pattern of results suggests that effects are being channeled through malaria—the disease, which is likely to increase with forest loss, tends to disproportionately infect women during their first pregnancy, thus causing greater harm to the children born from these pregnancies.  相似文献   

4.
A policy to control the spread of HIV infection   总被引:1,自引:0,他引:1  
Prevention of transmission of HIV infection is the most important public health concern of the AIDS epidemic. To date, unfortunately, we have failed to contain the epidemic. The increasingly rapid spread of HIV into the IV drug-abusing population and subsequent heterosexual transmission represent a further failure of the public health system. Current organization of the public health programs, especially the lack of independence and adequate financial and personnel support, is an extremely serious problem. More funding may not be the answer, unless there is better organization. Identification of infected individuals and a vigorous education program must be implemented. HIV antibody-positive individuals should be followed carefully in order to evaluate the risk factors for AIDS and efficacy of specific interventions.  相似文献   

5.
As the largest developing country, China has been suffering from resource shortage and serious environmental pollution. Evaluation and improvement of the regional environmental efficiency is crucial to pursuing the balance between economic development and environmental protection. This paper used a regional environmental efficiency SBM (slack-based measure) (REES) model which treats environmental pollution as undesirable outputs to evaluate the environmental efficiency of 30 provincial administrative regions (PARs) in China from 2005 to 2011 and investigated the factors affecting environmental efficiency using the Tobit regression model. The results indicate that there is distinct difference in environmental efficiency amongst each PAR. The GDP per capita, industrial structure, innovation capability, environmental awareness of local government and population density have significant positive impacts, while energy intensity exerts a significantly negative effect on environmental efficiency. In order to make more effective policies for improving China’s regional environmental efficiency, the hierarchical cluster analysis was applied to divide the 30 PARs into 3 sub-regions. A number of policy recommendations were provided for improving environmental efficiency according to the characteristics of each sub-region, which are helpful for the Chinese government to achieve the targets of environmental protection along with the economic development in the coming years.  相似文献   

6.
Air pollution is a serious environmental issue that has been long recognized. Whereas government policies attempt to reduce air pollution by controlling various pollution sources, research on risk perception of air pollution tends to treat air pollution as a single unified risk and neglects the complication of the polluting sources. Previous research consistently demonstrates that lay people have an inaccurate understanding of air pollution and are unwilling to change their behaviors to decrease pollution. However, these findings can hardly be employed in policy-making because researchers and policy-makers treat air pollution differently. The aim of the present study is to obtain a nuanced understanding of people's risk perception of air pollution from different sources. Moreover, we propose a new risk dimension, Self-Relevancy, and try to understand people's reluctance to change their behaviors to reduce pollution. Three main findings emerged. First, we demonstrated that people perceived each air pollution source differently. Second, factor analysis of risk characteristics showed that ratings of Self-Relevancy questions mainly loaded on the same factor, which indicates the robustness of the Self-Relevancy risk dimension. Finally, we found that people's ratings of Self-Relevancy positively predicted their perceived risk for some of the pollution sources. These findings highlight the importance of investigating sub-categories of risks and exploring the risk dimension of Self-Relevancy in future risk perception research to provide detailed and informative data for policy-makers.  相似文献   

7.
There is a great need to determine the factors that influence the hunting, butchering and eating of bushmeat to better manage the important social, public health and conservation consequences of these activities. In particular, the hunting and butchering of wild animals can lead to the transmission of diseases that have potentially serious consequences for exposed people and their communities. Comprehension of these risks may lead to decreased levels of these activities. To investigate these issues, 3971 questionnaires were completed to examine the determinants of the hunting, butchering and eating of wild animals and perceptions of disease risk in 17 rural central African villages. A high proportion of individuals reported perceiving a risk of disease infection with bushmeat contact. Individuals who perceived risk were significantly less likely to butcher wild animals than those who perceived no risk. However, perception of risk was not associated with hunting and eating bushmeat (activities that, compared with butchering, involve less contact with raw blood and body fluids). This suggests that some individuals may act on perceived risk to avoid higher risk activity. These findings reinforce the notion that conservation programs in rural villages in central Africa should include health-risk education. This has the potential to reduce the levels of use of wild animals, particularly of certain endangered species (e.g. many non-human primates) that pose a particular risk to human health. However, as the use of wild game is likely to continue, people should be encouraged to undertake hunting and butchering more safely for their own and their community's health.  相似文献   

8.
Conversion of tropical forests is among the primary causes of global environmental change. The loss of their important environmental services has prompted calls to integrate ecosystem services (ES) in addition to socio‐economic objectives in decision‐making. To test the effect of accounting for both ES and socio‐economic objectives in land‐use decisions, we develop a new dynamic approach to model deforestation scenarios for tropical mountain forests. We integrate multi‐objective optimization of land allocation with an innovative approach to consider uncertainty spaces for each objective. These uncertainty spaces account for potential variability among decision‐makers, who may have different expectations about the future. When optimizing only socio‐economic objectives, the model continues the past trend in deforestation (1975–2015) in the projected land‐use allocation (2015–2070). Based on indicators for biomass production, carbon storage, climate and water regulation, and soil quality, we show that considering multiple ES in addition to the socio‐economic objectives has heterogeneous effects on land‐use allocation. It saves some natural forest if the natural forest share is below 38%, and can stop deforestation once the natural forest share drops below 10%. For landscapes with high shares of forest (38%–80% in our study), accounting for multiple ES under high uncertainty of their indicators may, however, accelerate deforestation. For such multifunctional landscapes, two main effects prevail: (a) accelerated expansion of diversified non‐natural areas to elevate the levels of the indicators and (b) increased landscape diversification to maintain multiple ES, reducing the proportion of natural forest. Only when accounting for vascular plant species richness as an explicit objective in the optimization, deforestation was consistently reduced. Aiming for multifunctional landscapes may therefore conflict with the aim of reducing deforestation, which we can quantify here for the first time. Our findings are relevant for identifying types of landscapes where this conflict may arise and to better align respective policies.  相似文献   

9.
Aim Habitat loss and climate change are two major drivers of biological diversity. Here we quantify how deforestation has already changed, and how future climate scenarios may change, environmental conditions within the highly disturbed Atlantic forests of Brazil. We also examine how environmental conditions have been altered within the range of selected bird species. Location Atlantic forests of south‐eastern Brazil. Methods The historical distribution of 21 bird species was estimated using Maxent . After superimposing the present‐day forest cover, we examined the environmental niches hypothesized to be occupied by these birds pre‐ and post‐deforestation using environmental niche factor analysis (ENFA). ENFA was also used to compare conditions in the entire Atlantic forest ecosystem pre‐ and post‐deforestation. The relative influence of land use and climate change on environmental conditions was examined using analysis of similarity and principal components analysis. Results Deforestation in the region has resulted in a decrease in suitable habitat of between 78% and 93% for the Atlantic forest birds included here. Further, Atlantic forest birds today experience generally wetter and less seasonal forest environments than they did historically. Models of future environmental conditions within forest remnants suggest generally warmer conditions and lower annual variation in rainfall due to greater precipitation in the driest quarter of the year. We found that deforestation resulted in a greater divergence of environmental conditions within Atlantic forests than that predicted by climate change. Main conclusions The changes in environmental conditions that have occurred with large‐scale deforestation suggest that selective regimes may have shifted and, as a consequence, spatial patterns of intra‐specific variation in morphology, behaviour and genes have probably been altered. Although the observed shifts in available environmental conditions resulting from deforestation are greater than those predicted by climate change, the latter will result in novel environments that exceed temperatures in any present‐day climates and may lead to biotic attrition unless organisms can adapt to these warmer conditions. Conserving intra‐specific diversity over the long term will require considering both how changes in the recent past have influenced contemporary populations and the impact of future environmental change.  相似文献   

10.
Ecological gradients have long been recognized as important regions for diversification and speciation. However, little attention has been paid to the evolutionary consequences or conservation implications of human activities that fundamentally change the environmental features of such gradients. Here we show that recent deforestation in West Africa has homogenized the rainforest-savanna gradient, causing a loss of adaptive phenotypic diversity in a common rainforest bird, the little greenbul (Andropadus virens). Previously, this species was shown to exhibit morphological and song divergence along this gradient in Central Africa. Using satellite-based estimates of forest cover, recent morphological data, and historical data from museum specimens collected prior to widespread deforestation, we show that the gradient has become shallower in West Africa and that A. virens populations there have lost morphological variation in traits important to fitness. In contrast, we find no loss of morphological variation in Central Africa where there has been less deforestation and gradients have remained more intact. While rainforest deforestation is a leading cause of species extinction, the potential of deforestation to flatten gradients and inhibit rainforest diversification has not been previously recognized. More deforestation will likely lead to further flattening of the gradient and loss of diversity, and may limit the ability of species to persist under future environmental conditions.  相似文献   

11.
The Rio Cajarí Extractive Reserve (RCER) is a sustainable use protected area located in Southern Amapá state, Brazil. This protected area is home to traditional agro-extractive families, but has been increasingly invaded by commercial agriculture producers. In this work, we test the hypothesis that the RCER implementation has distinctly affected spatial patterns of deforestation and rates of bare soil and secondary forest formation by the social groups occupying the protected area and its surrounding area. Detailed maps of vegetation cover and deforestation were elaborated, based on Landsat TM images from 1991, 1998, 2007 and 2008 and Linear Spectral Mixture Models. Based on an extensive fieldwork, patches were classified according to the agents causing deforestation and characterized with ten explanatory variables. A discriminant function analysis was used to identify homogeneous groups based on the data. Results show increased rates and distinct spatial patterns of deforestation by three groups: extractivists, non traditional commercial agriculture producers, and a less representative group constituted of miners, cattle and timber producers. In all analyzed dates, clearings by the extrativist community presented the highest total area and smaller average sizes and were located in close proximity to villages. Deforestation patches by the non-traditional group were exclusively associated with ombrophilous forests; these presented higher average sizes and proximity indexes, and showed increased aggregation and large cluster formation. No significant differences were observed in deforestation patterns by the three groups inside or outside the reserve.  相似文献   

12.
The relationship between poverty and nutrition is a two-sided one: on the one hand, economic growth (which is generally associated with an eradication of poverty) leads to reduced malnutrition. On the other hand, nutrition is one of the key ingredients for human capital formation, which in turn represents one of the fundamental factors of growth. There are numerous studies that show the correlates of malnutrition using both household- and community-level variables. However, few of these studies allow for the potential endogeneity of community infrastructure or indicate their interplay with characteristics of the mother. The current study considers the socio-economic determinants of child malnutrition and investigates how programs compensate for the increased risks facing young mothers and their children or substitute for a low social status of the mother in the household. The empirical results show that children of mothers giving birth at a young age are disadvantaged in terms of their anthropometric status. Interaction effects of the presence of a non-governmental organization (NGO) or a health post in the village with characteristics of the mother stress the important role played by these institutions in helping disadvantaged mothers overcome their difficulties. These findings have implications for efficient program design and represent a further step towards gaining an improved understanding of the complex determinants of child (mal)nutrition.  相似文献   

13.
The occurrence of outbreaks of cholera in Africa in 1970 and in Latin America in 1991, mainly in coastal communities, and the appearance of the new serotype Vibrio cholerae O139 in India and subsequently in Bangladesh have stimulated efforts to understand environmental factors influencing the growth and geographic distribution of epidemic Vibrio cholerae serotypes. Because of the severity of recent epidemics, cholera is now being considered by some infectious disease investigators as a "reemerging" disease, prompting new work on the ecology of vibrios. Epidemiological and ecological surveillance for cholera has been under way in four rural, geographically separated locations in Bangladesh for the past 4 years, during which both clinical and environmental samples were collected at biweekly intervals. The clinical epidemiology portion of the research has been published (Sack et al., J. Infect. Dis. 187:96-101, 2003). The results of environmental sampling and analysis of the environmental and clinical data have revealed significant correlations of water temperature, water depth, rainfall, conductivity, and copepod counts with the occurrence of cholera toxin-producing bacteria (presumably V. cholerae). The lag periods between increases or decreases in units of factors, such as temperature and salinity, and occurrence of cholera correlate with biological parameters, e.g., plankton population blooms. The new information on the ecology of V. cholerae is proving useful in developing environmental models for the prediction of cholera epidemics.  相似文献   

14.
The World Health Organization (WHO) and other organizations report that the prevalence of human diseases during the past decade is rapidly increasing. Population growth and the pollution of water, air, and soil are contributing to the increasing number of human diseases worldwide. Currently an estimated 40% of world deaths are due to environmental degradation. The ecology of increasing diseases has complex factors of environmental degradation, population growth, and the current malnutrition of about 3.7 billion people in the world.  相似文献   

15.
Homegardens are integral part of rural households in Bangladesh. The present study examines some physical, biological, and socioeconomic characteristics of 32 homegardens randomly selected from four villages representing different agro-ecological conditions, variable population densities, and market opportunities. The study results suggest that large numbers of plant and animal species occupy homegardens, and their composition and intensity of cultivation vary directly with the household physiologic density and access to urban markets, and inversely with environmental constraints to agriculture. Homegardens form the activity space for household women and children, who perform most homegarden farming tasks. Uses of home generated inputs at no or low cost make homegardens economically more efficient and sustainable compared to non-homegarden rice farming. In the context of the intensive subsistence agriculture patterns that dominate Bangladesh, homegardens contribute significantly to smallholder household income.  相似文献   

16.
董彬 《生态科学》2012,31(5):596-600
随着环渤海地区经济的快速发展和人口的急剧增长,排入渤海海域的污染物质总量不断增加,污染物质的长期增加和积累造成了渤海环境质量的急剧恶化。渤海环境污染问题日益严重,备受人们的重视。在查阅大量相关文献及实际调查基础上,论述渤海污染现状,主要包括富营养化、重金属污染、石油类污染、沉积物形成的二次污染等;分析导致其污染的原因和危害:陆地污染物的大量排入、海水养殖、油气资源的不合理开发利用和管理体制的不完善。在此基础上,从可持续发展的角度提出了防治渤海污染、改善渤海环境的对策,主要包括依法治海、建立简洁高效的管理机制、应用新技术新手段以及加强预报工作等。  相似文献   

17.
Government based Payments for Ecosystem Services (PES) have been criticized for not maximizing environmental effectiveness through appropriate targeting, while instead prioritizing social side-objectives. In Mexico, existing literature on how the Payments for Ecosystem Services-Hydrological program (PSA-H) has targeted deforestation and forest degradation shows that both the process of identifying the eligible areas and the choice of the selection criteria for enrolling forest parcels have been under the influence of competing agendas. In the present paper we study the influence of the PSA-H multi-level governance on the environmental effectiveness of the program–the degree to which forest at high risk of deforestation is enrolled- building from a “policyscape” framework. In particular, we combine governance analysis with two distinct applications of the policyscape framework: First, at national level we assess the functional overlap between the PSA-H and other environmental and rural programs with regard to the risk of deforestation. Second, at regional level in the states of Chiapas and Yucatan, we describe the changing policy agenda and the role of technical intermediaries in defining the temporal spatialization of the PSA-H eligible and enrolled areas with regard to key socio-economic criteria. We find that, although at national level the PSA-H program has been described as coping with both social and environmental indicators thanks to successful adaptive management, our analysis show that PSA-H is mainly found in communities where deforestation risk is low and in combination with other environmental programs (protected areas and forest management programs). Such inertia is reinforced at regional level as a result of the eligible areas’ characteristics and the behaviour of technical intermediaries, which seek to minimise transaction costs and sources of uncertainty. Our project-specific analysis shows the importance of integrating the governance of a program in the policyscape framework as a way to better systematize complex interactions at different spatial and institutional scales between policies and landscape characteristics.  相似文献   

18.
Many serious emerging zoonotic infections have recently arisen from bats, including Ebola, Marburg, SARS-coronavirus, Hendra, Nipah, and a number of rabies and rabies-related viruses, consistent with the overall observation that wildlife are an important source of emerging zoonoses for the human population. Mechanisms underlying the recognized association between ecosystem health and human health remain poorly understood and responding appropriately to the ecological, social and economic conditions that facilitate disease emergence and transmission represents a substantial societal challenge. In the context of disease emergence from wildlife, wildlife and habitat should be conserved, which in turn will preserve vital ecosystem structure and function, which has broader implications for human wellbeing and environmental sustainability, while simultaneously minimizing the spillover of pathogens from wild animals into human beings. In this review, we propose a novel framework for the holistic and interdisciplinary investigation of zoonotic disease emergence and its drivers, using the spillover of bat pathogens as a case study. This study has been developed to gain a detailed interdisciplinary understanding, and it combines cutting-edge perspectives from both natural and social sciences, linked to policy impacts on public health, land use and conservation.  相似文献   

19.
Light-brown apple moths (LBAMs) are Australian leafrollers of the genus Epiphyas, capable of infesting orchards and other horticultural crops. Currently, five species are recognized, two of which, E. postvittana and E. pulla, can be serious economic pests. By means of principal-components and group-average cluster analyses applied to six parameters of demographic performance, two forms suspected of being interspecific hybrids were tested comparatively with possible parent species, and were found to be indistinguishable from E. postvittana. The frequency distribution of cornuti, a structural feature of the male genitalia used in identification, was investigated experimentally in the two economic species and their hybrids. The numerical variability of this character was shown to be much greater than had been recognized previously. It was found also that, in E. postvittana, cornuti frequencies may change in response to environmental influences. Hybrids tended to have cornuti numbers intermediate between those of their progenitors. LBAMs seem to be undergoing rapid evolutionary change in response to man-induced alterations in the environment, and represent a hazard to horticulture not only in Australia, but possibly also in any temperate or sub-tropical region to which they might gain access overseas. The situation would justify undertaking a systematic, Australia-wide, survey of these and related leafrollers.  相似文献   

20.
Whilst high‐resolution spatial variables contribute to a good fit of spatially explicit deforestation models, socio‐economic processes are often beyond the scope of these models. Such a low level of interest in the socio‐economic dimension of deforestation limits the relevancy of these models for decision‐making and may be the cause of their failure to accurately predict observed deforestation trends in the medium term. This study aims to propose a flexible methodology for taking into account multiple drivers of deforestation in tropical forested areas, where the intensity of deforestation is explicitly predicted based on socio‐economic variables. By coupling a model of deforestation location based on spatial environmental variables with several sub‐models of deforestation intensity based on socio‐economic variables, we were able to create a map of predicted deforestation over the period 2001–2014 in French Guiana. This map was compared to a reference map for accuracy assessment, not only at the pixel scale but also over cells ranging from 1 to approximately 600 sq. km. Highly significant relationships were explicitly established between deforestation intensity and several socio‐economic variables: population growth, the amount of agricultural subsidies, gold and wood production. Such a precise characterization of socio‐economic processes allows to avoid overestimation biases in high deforestation areas, suggesting a better integration of socio‐economic processes in the models. Whilst considering deforestation as a purely geographical process contributes to the creation of conservative models unable to effectively assess changes in the socio‐economic and political contexts influencing deforestation trends, this explicit characterization of the socio‐economic dimension of deforestation is critical for the creation of deforestation scenarios in REDD+ projects.  相似文献   

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