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1.
ABSTRACT: Sustained interest in and concern about the health status of the aquatic environment has resulted in extensive research focused on (1) effects of pollution on survival, growth, and reproduction of resource species at all life stages; (2) diseases of fish and shellfish, as they may be related to pollution and as they may serve as indicators of environmental stress; and (3) contaminant body burdens in fish and shellfish - their effects on the aquatic animals and their potential effects on humans. Effects, lethal and sublethal, of pollutants on life history stages of fish and shellfish have been documented, as have impacts on local stocks in badly degraded habitats, but as yet there has been no adequate quantitative demonstration of effects on entire aquatic species - probably because of the difficulty in sorting out relative effects of the many environmental factors that influence abundance. Sublethal effects, especially those that result in disease, have been examined intensively, and some diseases and disease syndromes have been associated statistically with pollution. Other pollution indicators (biochemical, physiological, genetic, behavioral, and ecological) have also received some attention, as have body burdens of contaminants in aquatic species. Research, especially that conducted during the past decade, has done much to clarify the many pathways and toxic effects of contaminants on aquatic animals, and has also helped to identify mechanisms for survival of fish and shellfish in the presence of environmental changes caused by human activities.  相似文献   

2.
There is increasing concern about the use of lethal methods to control wild mammal populations, especially those methods that may have significant impacts on animal welfare. The continued use of dogs to hunt wild mammals in England and Wales, principally foxes (Vulpes vulpes), red deer (Cervus elaphus), brown hares (Lepus europaeus) and mink (Mustela vison), has become a focus for political debate and has been the subject of a recent UK government inquiry. This paper reports the results of a questionnaire study to quantify the use, effectiveness and acceptability of the different methods currently used to manage these four species, and future changes in management following a possible ban on hunting with dogs. There was no straightforward relationship between culling pressure and perceived pest status of the different species from the questionnaire data. For foxes and brown hares, the proportion of land managers (practitioners) carrying out lethal control was higher than that considering these species to be pests. However, the reverse was the case for mink. The most frequently used and effective control methods, which were most acceptable to practitioners and public alike, were various forms of shooting. The general public perceived hunting with dogs as one of the least acceptable means of control for all four species. Practitioners thought that hunting with dogs for red deer and the use of terriers against foxes were among the least acceptable forms of control, but considered hunting with dogs in other situations and for other species to be relatively acceptable. Most practitioners said a ban on hunting with dogs would make no difference to their management of the four species. A ban on hunting with dogs would have minimal impact on populations of foxes, red deer and mink, but it may be of conservation benefit to hares.  相似文献   

3.
姚小宁 《四川环境》2005,24(5):57-59,63
本文针对传染病医院建筑给排水的设计进行研究.从实例出发,分析了传染病院的功能特点及不同类型传染病所采取的措施要点,从有利于洁净及防止二次污染、污水处理及消防给水设计等几个方面提出自己的看法及相应的技术措施.  相似文献   

4.
Quantifying the human health benefits of curbing air pollution in Shanghai   总被引:1,自引:0,他引:1  
Urban development in the mega-cities of Asia has caused detrimental effects on the human health of its inhabitants through air pollution. However, averting these health damages by investing in clean energy and industrial technologies and measures can be expensive. Many cities do not have the capital to make such investments or may prefer to invest that capital elsewhere. In this article, we examine the city of Shanghai, China, and perform an illustrative cost/benefit analysis of air pollution control. Between 1995 and 2020 we expect that Shanghai will continue to grow rapidly. Increased demands for energy will cause increased use of fossil fuels and increased emissions of air pollutants. In this work, we examine emissions of particles smaller than 10 microm in diameter (PM10), which have been associated with inhalation health effects. We hypothesize the establishment of a new technology strategy for coal-fired power generation after 2010 and a new industrial coal-use policy. The health benefits of pollution reduction are compared with the investment costs for the new strategies. The study shows that the benefit-to-cost ratio is in the range of 1-5 for the power-sector initiative and 2-15 for the industrial-sector initiative. Thus, there appear to be considerable net benefits for these strategies, which could be very large depending on the valuation of health effects in China today and in the future. This study therefore provides economic grounds for supporting investments in air pollution control in developing cities like Shanghai.  相似文献   

5.
Glyphosate [N-(phosphonomethyl) glycine]-resistant crops (GRCs), canola (Brassica napus L.), cotton (Gossypium hirsutum L.), maize (Zea mays L.), and soybean [Glycine max (L.) Merr.] have been commercialized and grown extensively in the Western Hemisphere and, to a lesser extent, elsewhere. Glyphosate-resistant cotton and soybean have become dominant in those countries where their planting is permitted. Effects of glyphosate on contamination of soil, water, and air are minimal, compared to some of the herbicides that they replace. No risks have been found with food or feed safety or nutritional value in products from currently available GRCs. Glyphosate-resistant crops have promoted the adoption of reduced- or no-tillage agriculture in the USA and Argentina, providing a substantial environmental benefit. Weed species in GRC fields have shifted to those that can more successfully withstand glyphosate and to those that avoid the time of its application. Three weed species have evolved resistance to glyphosate in GRCs. Glyphosate-resistant crops have greater potential to become problems as volunteer crops than do conventional crops. Glyphosate resistance transgenes have been found in fields of canola that are supposed to be non-transgenic. Under some circumstances, the largest risk of GRCs may be transgene flow (introgression) from GRCs to related species that might become problems in natural ecosystems. Glyphosate resistance transgenes themselves are highly unlikely to be a risk in wild plant populations, but when linked to transgenes that may impart fitness benefits outside of agriculture (e.g., insect resistance), natural ecosystems could be affected. The development and use of failsafe introgression barriers in crops with such linked genes is needed.  相似文献   

6.
This paper reviews the use of additives to reduce odor and ammonia (NH3) emissions from livestock wastes. Reduction of NH3 volatilization has been shown to be possible, particularly with acidifying and adsorbent additives, and potential exists to develop further practical and cost-effective additives in this area. Masking, disinfecting, and oxidizing agents can provide short-term control of malodor, but as the capacity of these additives is finite, they require frequent reapplication. Microbial-based digestive additives may offer a solution to this problem as they are regenerative, but they appear to have been developed without a thorough understanding of microbiological processes occurring in livestock wastes. Currently, their use to reduce odor or NH3 emissions cannot be recommend. If the potential of these types of additives is to be realized, research needs to shift from simply evaluating these unknown products to investigating known strains of bacteria or enzymes with known modes of action. To protect the farmers' interest, standard independent test procedures are required to evaluate efficacy. Such tests should be simple and quantify the capacity of the additive to perform as claimed. The principle use of additives needs to be identified and addressed during their development. Producers may not use effective additives in one area if they further compound other problems that they perceived to be more important. There is the potential to use additives to treat other problems associated with livestock wastes, particularly to improve handling properties, reduce pollution potential to watercourses, and reduce pathogenic bacteria. Further work is required in these areas.  相似文献   

7.
The aim of this review is to assess the ethical implications of finfish aquaculture, regarding fish welfare and environmental aspects. The finfish aquaculture industry has grown substantially the last decades, both as a result of the over-fishing of wild fish populations, and because of the increasing consumer demand for fish meat. As the industry is growing, a significant amount of research on the subject is being conducted, monitoring the effects of aquaculture on the environment and on animal welfare. The areas of concern when it comes to animal welfare have here been divided into four different stages: breeding period; growth period; capturing and handling; and slaughter. Besides these stages, this report includes a chapter on the current evidence of fish sentience, since this issue is still being debated among biologists. However, most biologists are at present acknowledging the probability of fish being sentient creatures. Current aquaculture practices are affecting fish welfare during all four of the cited stages, both on physical and mental levels, as well as on the ability of fish to carry out natural behaviors. The effect fish farming has on the environment is here separated into five different categories: the decline of wild fish populations; waste and chemical discharge; loss of habitat; spreading of diseases; and invasion of exotic organisms. There is evidence of severe negative effects on the environment when looking at these five categories, even when considering the difficulty of studying environmental effects, due to the closely interacting variables. The ethical arguments and scientific evidences here reviewed have not all come to the same conclusions. Nevertheless, the general agreement is that current aquaculture practices are neither meeting the needs of fish nor environment. Thus, the obvious environmental and animal welfare aspects of finfish aquaculture make it hard to ethically defend a fish diet.  相似文献   

8.
Air quality in the UK, although vastly improved from the smogs of the 1950s, now faces a new set of challenges from a variety of sources and pollutants. Poor air quality has long been associated with urban areas, but it is becoming clear that many rural locations also have locations likely to exceed the UK Air Quality Strategy-objectives: This paper will examine the extent to which rural authorities have been engaged in the local air-quality management (LAQM) process, a new regime by which air quality control is being accomplished in the UK. Results are presented from a questionnaire survey of environmental health officers of 100 rural authorities undertaken in January 1999. The paper investigates both the technical aspects of the LAQM process as well as the management approaches. The current progress of rural authorities, and some of the problems they face, are discussed particularly in comparison with urban areas. It is concluded that some rural authorities with air pollution problems stemming either from within or outwith their borough, may face significant challenges from the LAQM review and assessment process, particularly where air pollution responsibilities have only relatively recently been addressed. Rural authorities seem to be embracing these new responsibilities enthusiastically, but it is almost inevitable that they will be trailing behind urban authorities who have several decades of experience and joint working to draw upon.  相似文献   

9.
Prions are the etiological agents of transmissible spongiform encephalopathies (TSSEs), a class of fatal neurodegenerative diseases affecting humans and other mammals. The pathogenic prion protein is a misfolded form of the host-encoded prion protein and represents the predominant, if not sole, component of the infectious agent. Environmental routes of TSE transmission areimplicated in epizootics of sheep scrapie and chronic wasting disease (CWD) of deer, elk, and moose. Soil represents a plausible environmental reservoir of scrapie and CWD agents, which can persist in the environment for years. Attachment to soil particles likely influences the persistence and infectivity of prions in the environment. Effective methods to inactivate TSE agents in soil are currently lacking, and the effects of natural degradation mechanisms on TSE infectivity are largely unknown. An improved understanding of the processes affecting the mobility, persistence, and bioaviailability of prions in soil is needed for the management of TSE-contaminated environments.  相似文献   

10.
The hazards associated with pathogens in land-applied animal and human wastes have long been recognized. Management of these risks requires an understanding of sources, concentrations, and removal by processes that may be used to treat the wastes; survival in the environment; and exposure to sensitive populations. The major sources are animal feeding operations, municipal wastewater treatment plant effluents, biosolids, and on-site treatment systems. More than 150 known enteric pathogens may be present in the untreated wastes, and one new enteric pathogen has been discovered every year over the past decade. There has been increasing demand that risks associated with the land treatment and application be better defined. For risks to be quantified, more data are needed on the concentrations of pathogens in wastes, the effectiveness of treatment processes, standardization of detection methodology, and better quantification of exposure.  相似文献   

11.
Slovene agriculture is going throughdrastic changes. Most of the land is stillowned by small farmers. The production isoriented to the market and is based on modernWestern technology. It is associated withincreasing pollution and is becoming a seriousthreat to biodiversity. Many of the wild plantsare endangered due to genetic erosion withinspecies. The traditional crops and varietiesare being replaced by imported materials andthe use of chemicals has been increasing. Manyof the traditional varieties have beenneglected and/or lost. The existing germplasmcollections are incomplete and frequently donot include traditional varieties. There areonly a few breeding organizations with limitedcapacities and collections. The legislation isnot efficient enough to protect the environmentand biotic diversity. Schools, media,religious, sport, tourist, and otherorganizations should be more active inpromoting the respect for biodiversity.  相似文献   

12.
A review on the effects of radiofrequency radiation from wireless telecommunications on living organisms and its possible impact on wild mammals are presented. Physical and technological characteristics of mobile telephone and phone masts, the scientific discoveries that are of interest in the study of their effects on the wildlife, action mechanisms on biological systems and experimental difficulties are described. Keeping in mind that electromagnetic pollution (in the microwave and radiofrequency range) is a possible source for decline of some mammal populations, it is of great importance to carry out studies on the effects of this new pollutant to wildlife. Some research types that could be useful to determine adverse health effects are proposed.  相似文献   

13.
The development of conservation strategies for nontimber forest products requires the characterization of the management systems and ethnoecological knowledge of the used species, as well as the analysis of the biological impacts of these processes. This study aimed to evaluate management systems and extractivist areas and related ethnoecological knowledge of Dimorphandra gardneriana (fava d’anta) in the semiarid region of Ceará, Northeast of Brazil. Fava d’anta produces fruits with high concentration of bioflavonoids, substances with various pharmacological properties, being exploited by extractivist communities in the mosaic of protected areas in Chapada do Araripe, Ceará. Ethnoecological knowledge has been concentrated on collectors who have been in activity for a longer time and/or plant the species. We identified three management systems that can impact in different ways on fava d’anta populations, depending on the area and level of human interference with the species. The extractivists respect the zoning of protected areas and do not enter in the full protection area, choosing areas with the highest tree density. The different systems produce a mosaic that creates different extraction opportunities and modifications to the local landscape and to fava d’anta populations. Factors that may have effects on the conservation of the species are the lack of supervision and overexploitation of the resource in native areas, while the factors that affect the health of extractivists are the infrastructure of the work and exposure to wild environments.  相似文献   

14.
Populations of introduced European wild boar, feral pigs, and combinations of both types (all Susscrola L.) inhabit thirteen areas in the National Park Service system. All parks have relatively stable populations, with the exception of Great Smoky Mountains National Park, which reported a rapidly expanding wild boar population. Suspected and documented impacts were apparently related to pig densities and sensitivity of the ecosystem; the three largest units with dense wild pig populations reported the most damage. Overall, wild pigs are a relatively minor problem for the Park Service; however, problems are severe in at least three parks, and there is potential for invasion of wild boars into several additional parks in the Appalachian Mountains. More specific information is needed on numbers of wild pigs and their impacts in the various parks.  相似文献   

15.
Wildlife managers are challenged with the task of deciding whether a management measure is appropriate or not, and furthermore they have to convince others about the merits of their decision. Population decline of some hare species (genus Lepus) has resulted in their Red Listing and conservation measures are being undertaken. Release or restocking is a frequent measure in some countries, and thousands of hares are released annually, mainly for hunting purposes. These hares can be obtained by either intensive or extensive rearing or translocation of the wild animals. Each method entails difficulties and different survival rates in the wild. Survival rates in the wild are low for hares intensively reared in cages but are higher for hares reared extensively in enclosures and wild translocated hares. The benefits of the hare release practice are significantly lower than the action’s implementation cost. Hare releases have not increased significantly the wild hare population or the hunting harvest in areas where the practice has been applied. The risk of genetic and evolutionary degradation and pathogen transmission is possible in wild populations. The need for wise management of this practice is evident and the term ‘Permitted Transferring Units’ should be introduced to denote regions where hares should not be transferred for rearing and release.  相似文献   

16.
Economic liberalization in former socialist countries may have various implications for their environmental sustainability. Positive effects of this process are potentially associated with improved efficiency, investments into cleaner technologies, responsiveness to environmentally aware markets, and ending subsidies to heavy industries. On the other hand, market liberalization may result in weaker environmental controls, economic instabilities distracting attention from environmental issues, and increasing orientation towards profit-making leading to more intensive exploitation of natural resources. In addition, trade liberalization may result in shifts towards more pollution and resource-intensive industries. This article seeks to quantify effects of economic restructuring in Russia on air pollution from productive economic sectors in the 1990s. Air pollution in Russia had significantly declined in 1991-1999, however, this decline was largely due to economic decline, as the overall pollution intensity of the economy had decreased only slightly. The factors that affected the pollution intensity are: (1) a decrease in the combined share of industrial and transport activities in the economy and (2) changing pollution intensities of the industrial and transport sectors. The pollution intensity of the Russian industry had remained relatively stable during the 1990s. This was the result of the two opposite and mutually canceling trends: (a) increasing shares of pollution-intensive branches such as metal smelting and oil production vs. less pollution intensive manufacturing and (b) decline in pollution intensities within the industrial branches. The article proposes a methodology by which the contribution of both factors to the overall pollution intensity of the industrial sector can be quantified. The pollution intensity of the Russian transport sector appears to have declined in the first half of the 1990s and increased in the second half. The most recent trend can be explained by a rising proportion of private motorcars used for transportation of people and goods instead of traditional rail and other public transport. The findings of the paper demonstrate that shifts towards more pollution-, resource- and energy-intensive industries as a result of economic liberalization emerges as a significant negative factor of the process of economic transition threatening sustainability of emerging market economies. A research agenda to further investigate these impacts is proposed.  相似文献   

17.
Recently the possible link between air pollution and asthma has been at the centre of much political, public and media attention. This concern has been fuelled by evidence of increasing respiratory ill health, especially in children, and the search for an explanation has focused upon environmental pollution, particularly emissions from road transport. Paradoxically this concern has not been induced by new findings that address the fundamental question of the importance of current levels of air pollution in the causation, severity and responses in asthma. Asthma is predominantly an allergic disease of the human airways. These airways are known to become inflamed in response to exposure to a host of environmental factors. This paper reviews evidence of a link between pollution and asthma and examines the role of pollution in the expression of asthma. In more than 90 percent of children in the UK with asthma the major allergen is a protein particle secreted by house dust mites and this is likely to be the cause of the disease in most sufferers. However, if air pollution has a role it must be expressed in one of three ways. First, certain pollutants acting together, singly, or with other environmental triggers, may cause changes in airways and cause symptoms in people already suffering from asthma. Secondly, air pollution may be causing the initiation of asthma by a mechanism independent of other factors. Thirdly, exposure to pollutants may act in combination with allergens to initiate the asthmatic tendency. The medical evidence for each of these possible roles will be discussed. It is crucial that answers are forthcoming to these questions in order that effective and timely air pollution control strategies may be introduced.This paper was delivered at the Global Forum '94 Academic Conference.  相似文献   

18.
Oil spills have become a major environmental hazard constituting serious social problems in Nigeria, especially in the oil producing communities. The spills contaminate the aquifer if the subsurface layers are not protected. Geoelectric technique of geophysical investigation has been used to evaluate the protective capacity of six oil producing communities: Oleh, Olomoro, Uzere, Afiesere, Ekakpamre and Uvwiamuge in the western Niger Delta. A total of 139 vertical electrical sounding (VES) using the Schlumberger electrode configuration were occupied in these communities. The longitudinal conductance maps delineated areas with poor (<0.1 mho), weak (0.1–0.19 mho), moderate (0.2–0.69 mho) and good protective capacity (0.7–4.9 mho). The study has shown that the protective capacity of most parts of the communities studied is poor with Uvwiamuge and Ekakpamre communities not protected hence the aquifer in these oil producing communities are vulnerable to contamination by hydrocarbon in the event of pollution. Hence proper environmental protection measures have been suggested to safeguard the aquifer from pollution by hydrocarbon in the event of spillage.  相似文献   

19.
This paper uses an integrated economic-environmental model to assess the point source pollution from major industries in Jefferson County, Northern Alabama. Industrial expansion generates employment, income, and tax revenue for the public sector; however, it is also often associated with the discharge of chemical pollutants. Jefferson County is one of the largest industrial counties in Alabama that experienced smog warnings and ambient ozone concentration, 1996-1999. Past studies of chemical discharge from industries have used models to assess the pollution impact of individual plants. This study, however, uses an extended Input-Output (I-O) economic model with pollution emission coefficients to assess direct and indirect pollutant emission for several major industries in Jefferson County. The major findings of the study are: (a) the principal emission by the selected industries are volatile organic compounds (VOC) and these contribute to the ambient ozone concentration; (b) the direct and indirect emissions are significantly higher than the direct emission by some industries, indicating that an isolated analysis will underestimate the emission by an industry; (c) while low emission coefficient industries may suggest industry choice they may also emit the most hazardous chemicals. This study is limited by the assumptions made, and the data availability, however it provides a useful analytical tool for direct and cumulative emission estimation and generates insights on the complexity in choice of industries.  相似文献   

20.
From a historical point of view, man's concern about the health and protection of water supply is the history of the dramatic reduction in acute communicable diseases due to water-borne micro-organisms. Now that these have been essentially eliminated, there has been a great reduction in concern by scientists and the medical profession with the health aspects of contaminated water. This, in spite of the fact that many concerned people and national advisory groups have reminded us that an increasing number of possible chemical and other hazards find their way into our water supplies and expose human populations to contaminants at low concentration levels without reliable knowledge as to their health effects. Too little research is being done on the health effects of chemicals, pesticides, and viruses. The fact that large populations are being exposed to these possible hazards raises legal and public policy questions. Persons who are largely ignorant of the possible harm of these substances are being exposed to them without consent. Often low level exposure to environmental contaminants is not known or not discovered until considerable time has passed. This raises the question concerning the burden which should be imposed on industry and others who introduce new substances in the environment. The best approach in solving this problem is to prohibit the new substance from being introduced into the environment until it has been shown by reliable studies that even low level exposure is not likely to harm human health.  相似文献   

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