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1.
Air pollution abatement strategies for controlling nitrogen dioxide, sulfur dioxide, and ozone emissions in the United States focus on a ‘standards-based’ approach. This approach places limits on air pollution by maintaining a baseline value for air quality, no matter what the ecosystem can or cannot withstand. In this paper, we present example critical levels maps for the conterminous U.S. developed using the ‘effects-based’ mapping approach as defined by the United Nations Economic Commission for Europe's Convention on Long-Range Transboundary Air Pollution, Task Force on Mapping. This approach emphasizes the pollution level or load capacity an ecosystem can accommodate before degradation occurs, and allows for analysis of cumulative effects. We present the first stage of an analysis that reports the distribution of exceedances of critial levels for NO2, SO2, and O3 in sensitive forest, crop, and natural vegetation ecosystems in the contiguous United States. We conclude that extrapolation to surrounding geographic areas requires the analysis of diverse and compounding factors that preclude simple extrapolation methods. Pollutant data depicted in this analysis is limited to locationally specific data, and would be enhanced by utilizing spatial statistics, along with converging associated anthropogenic and climatological factors. Values used for critical levels were derived from current scientific knowledge. While not intended to be a definitive value, adjustments will occur as the scientific community gains new insight to pollutant/receptor relationships. We recommend future analysis to include a refinement of sensitive receptor data coverages and to report relative proportions of exceedances at varying grid scales.  相似文献   

2.
Damage caused to materials exposed in the atmosphere constitutes one of the most important direct effects of acidifying air pollutants. Systematic field and laboratory investigations performed in the recent decade in many countries have contributed to a considerable increase in the knowledge on the mechanisms of the effects of pollutants, on the quantification of damage and on the assessment of the cost of damage. Beside the very important role of SO2 for several materials also studies of the direct or synergistic effect of NOx and O3 have contributed to the understanding of the complex pollution effects. Even if there are still considerable gaps of knowledge it seems that NOx and O3 may contribute in an important way to the deterioration of several materials also in indoor environments which are important for i.a. electronic equipment, storage conditions and museums. Important knowledge has been gained from the International Cooperation Project within UK ECE which is an extensive field exposure on 39 test sites. Dose-response relations have been obtained after 4-year exposure showing the effect of dry and wet deposition on corrosion of several material groups. Also the effect of micro- and mesoclimate on corrosion of building materials like plaster and bricks in different positions on buildings and locations within an urban area has been subject to systematic studies. Results from the studies are used i.a. for assessment of so called acceptable corrosion levels and for mapping areas where the levels are exceeded at different pollution scenarios, as well as for calculation of economic damage. Based on model studies for some city areas tentative calculations of damage cost have been performed for the European region. The indirect effects consist of increased corrosion due to water and soil acidification which are of importance in geologically sensitive areas. Structures which are in contact with soil and water represent a very great capital investment and are of vital importance to the community.  相似文献   

3.
The aim of the AIR-CLIM project is to perform an integrated analysis of the linkages between climate change and regional air pollution in Europe and to produce results that are relevant to European policy-making. Key elements of the analysis are on the impact side the exceedances of critical thresholds for air pollution and global change and on the cost side the estimates of costs to reduce emissions of greenhouse gases and air pollutants. The integrated modeling framework set up to meet these objectives consists of two state-of-the-art integrated models covering regional air pollution in Europe (RAINS) and global climate change (IMAGE), supplemented by new components. Based on a preliminary analysis it can be stated that climate change will make European vegetation in most regions less sensitive to acid deposition. Taking into account the emission trends the impacts of regional air pollution will decrease while the impacts of climate change increase. Different problems will be important in different regions: regional air pollution in Central and northern Europe, and climate change in southern Europe.  相似文献   

4.
There is growing concern that air pollution may have adverse impacts on crops in developing countries, yet this has been little studied. This paper addresses this issue, for a major leguminous crop of the Indian sub continent, examining the effect of air pollution in and around an Indian city. A field study was conducted using a gradient approach to elucidate the impact of air pollutants on selected production characteristics of Vigna radiata L. cv. Malviya Jyoti (mung bean) plants grown from germination to maturity at locations with differing concentrations of air pollutants around peri-urban and rural areas of Varanasi. The 6 -h daily mean SO2, NO2 and O3 concentrations varied from 8.05 to 32.2 ppb, 11.7 to 80.1 ppb and 9.7 to 58.5 ppb, respectively, between the sites. Microclimatic conditions did not vary significantly between the sites. Changes in plant performance at different sites were evaluated with reference to ambient air quality status. Reductions in biomass accumulation and seed yields were highest at the site experiencing highest concentrations of all three gaseous pollutants. The magnitude of response indicated that at peri-urban sites SO2, NO2 and O3 were all contributing to these effects, whereas at rural sites NO2 and O3 combinations appeared to have more influence. The quality of seed was also found to be negatively influenced by the ambient levels of pollutants. It is concluded that the air pollution regime of Varanasi City causes a major threat to mung bean plants, both in terms of yield and crop quality, with serious implications for the nutrition of the urban poor.  相似文献   

5.
The United Kingdom National Materials Exposure Programme was initiated in 1986 to study the effects of acid deposition on building materials. The output data in the form of empirical dose-response equations (described elsewhere) have been incorporated into a geographical information system (GIS). In addition, data for the stock at risk of building materials has also been used. The dose-response relations indicate a dominance of dry deposition of sulphur dioxide in the decay process. Critical level/load maps have been determined for a number of materials. General pollution and meteorological data sets are also included in the mapping process. Maps give ‘exceedence squares’ on a 20 km square grid basis, indicating the unprotected areas or those still at risk for a given scenario for SO2 reduction in the context of the UNECE protocol for sulphur. In order to derive maps of areas sensitive to pollutants in the future a model, HARM 7.2, is used for the prediction of distribution of emissions of pollutants in the UK. A series of maps has now been produced for different materials at 70% and 80% scenarios for the reduction of SO2. Studies of the sensitivity of the exceedence maps to the accuracy or variation of the components in the dose-response equations have been undertaken. Results from the mapping programme and the sensitivity analysis are presented together with discussion of the concept of critical loads of materials.  相似文献   

6.
Emberson  L.D.  Ashmore  M.R.  Murray  F.  Kuylenstierna  J.C.I.  Percy  K.E.  Izuta  T.  Zheng  Y.  Shimizu  H.  Sheu  B.H.  Liu  C.P.  Agrawal  M.  Wahid  A.  Abdel-Latif  N.M.  van Tienhoven  M.  de Bauer  L.I.  Domingos  M. 《Water, air, and soil pollution》2001,130(1-4):107-118
The predicted increases in emissions of primary pollutants in many rapidly industrializing countries may have severe consequences for the health and productivity of forest trees and agricultural crops. This paper presents a review of air pollution impacts on vegetation in developing countries by summarising information describing the direct impacts to vegetation caused by a number of air pollutants (sulphur dioxide (SO2), nitrogen oxides (NOx), ozone (O3) and Suspended Particulate Matter (SPM)). This information has been collected by experts from a number of rapidly industrializing countries in Asia, Latin America and Africa and includes observations of visible injury in the field and the use of transect studies and controlled experimental investigations to ascribe damage to different pollutant concentrations. The ability to synthesise this information to define exposure-response relationships and subsequent air quality guidelines similar to those established in North America and Europe is assessed. In addition, the use of regional and global models describing pollution concentrations is discussed with reference to assessing the extent of adverse impacts and identifying regions likely to be most at risk from air pollution, both for the present day and in the future. The evidence summarised in the paper clearly shows that current pollutant concentrations experienced in many developing countries, particularly Asia, can result in severe damage to vegetation and that without appropriate control measures such damage is likely to worsen in the future as pollutant emissions increase.  相似文献   

7.
During recent decades, ozone (O3) has gained much attention as a possible contributor to forest decline. Attempts have been made to set critical levels for O3 in order to protect vegetation. Damage to vegetation seems to depend on the pattern of exposure. Episodic peaks followed by periods with low concentrations are more phytotoxic than exposures with generally elevated concentrations but without peaks. The present experiment aims to examine whether O3 affects the wood production of beech seedlings. The seedlings were exposed to three different air pollution regimes: charcoal-filtered ambient air (CF), non-filtered ambient air (NF), and NF+30nl1?l?1 O3 8 hours day1 during summer periods (NFO). Basal stem diameter was measured regularly during three growing seasons. The relative diameter increase was significantly reduced with increased O3 concentration. AOT40 is calculated for all treatments and evaluated in relation to the relative diameter growth.  相似文献   

8.
Nitrogen dioxide is an important gaseous air pollutant. It plays a major role in atmospheric chemistry, particularly in the formation of secondary air pollutants, and contributes to environmental acidification. A comprehensive assessment of NO2 levels in the atmosphere is required for developing effective strategies for control of air pollution and air quality improvement. Air pollution is a serious problem in all major cities of Pakistan and needs to be addressed to minimize detrimental effects on human health and urban vegetation. In this research, we focused on the monitoring of NO2 levels in the urban environment of Rawalpindi city. Because of the lack of expensive continuous sampling devices and to get a good spatial coverage of the NO2 concentrations in the study area, NO2 passive samplers were exposed at 42 different sites within the city limits of Rawalpindi from January to December, 2008. Samplers were exchanged every 10 days and the associated meteorological conditions like temperature, wind speed, rainfall and relative humidity were also monitored. The average NO2 concentration was found to be 27.46?±?0.32 ppb. The highest values of NO2 were measured near to main roads and educational institutions due to intense flow of road vehicles. Moreover, the study showed that the values obtained for NO2 for all sampling points exceeded the annual limit value set by World Health Organization. So, this is very important to take different steps to control this before it becomes a serious hazard for people living in those areas.  相似文献   

9.
The acute effects of air pollution on human health and the environment are well understood and the arguments for measures to prevent local, gross pollution are strong. Governments and the public will accept the need for controls where effects are obvious. At the broader scale where effects may be more subtle, and where the costs of abatement are high, a convincing case is necessary before acceptable solutions are adopted. An education process is needed to provide the relevant facts in an understandable form. For major air pollutants, where international agreement for control of emissions is required, effect-based instruments have proved successful in Europe. These are designed to be cost effective by offering protection to the more sensitive areas by targeting the cheapest emission controls on the sources responsible for effects. This level of complexity has demanded improved education and communication for all those involved in the decision-making process. The principles and approaches that have provided success are discussed. Attention to these is needed in the future if more stringent and costlier measures are to be agreed.  相似文献   

10.
Air quality levels vary over regions due to meteorological factors, proximity to sources, and local conditions (i.e., topography). The Northeast USA is subjected to pollution inputs from both local sources and those from the upwind Midwest USA that are transported by prevailing meteorological patterns. With the passage of the Clean Air Act in 1970 and the establishment of the National Ambient Air Quality Standards (NAAQS), national levels of air pollutants have declined significantly. Our study compared air quality time trends between five of the largest cities within New York State (Albany, Buffalo, New York City, Rochester, and Syracuse) and statewide means to national trends. Data were obtained from the NYS Department of Environmental Conservation (DEC) Bureau of Air Quality Surveillance for six criteria pollutants: carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), particulate matter (PM2.5), and lead (Pb). Regional Kendall tests found significant downward trends for each pollutant statewide from 1980 to 2007, while trends by city varied by decade and pollutant. The evaluation of historical trends of pollution in industrialized nations is useful in showing recent air quality improvements and also in the understanding what can be the result in air pollutant controls in those developing nations currently experiencing high levels of pollution.  相似文献   

11.
Air pollution is a recognized health hazard for man and domestic animals. Although industrial air pollutants have been known to cause sickness and death of the latter for over 100 years, little attention has been paid to their importance in the decline of wildlife. This paper reviews the existing information on the effects of industrial air pollutants on vertebrate wildlife. Air pollutants have had a worldwide effect on both wild birds and wild mammals, often causing marked decreases in local animal populations. The major effects of industrial air pollution on wildlife include direct mortality, debilitating industrial-related injury and disease, physiological stress, anaemia, and bioaccumulation. Some air pollutants have caused a change in the distribution of certain wildlife species.  相似文献   

12.
The purpose of this paper is to summarize the current state of knowledge concerning direct forest damage caused by atmospheric gaseous pollutants. The major gaseous pollutants affecting forest growth are O3, SO2, and HF. Ozone is the most prevalent phytotoxic air pollutant on a regional scale in eastern North America. It has been demonstrated to cause foliar injury and growth effects on trees in both laboratory and field studies. Both SO2 and HF have been found to cause damage to forests primarily in the vicinity of strong point sources. Case histories of forest damage are reported in the paper which describe foliar and radial growth effects, with associated volume losses. Threshold levels of the gaseous pollutants causing effects on forest growth are provided.  相似文献   

13.
A number of positive changes have taken place since Estonia regained its independence in 1991. Air pollution from stationary sources has decreased over 2.5 times during 1990–1999, emissions of solid particles and SO2 have declined 74% and 60%, respectively. The content of heavy metals in Estonian mosses has decreased in comparison with the early 1990s. Last five years occurrence of different kind of damages on decidious trees has not been frequent. Those facts indicate that air pollution with heavy metals and other pollutants has diminished during the last few years. As the pH of precipitation fluctuates in different parts of Estonia, it is very important to study the effect of precipitation on ecosystems on the basis of critical loads. Results indicate that, as for eutrophicating nitrogen, the actual nitrogen deposition in North-East Estonia and West-Estonian islands roughly coincides with the limits for pollution endurance. This pattern also applies to the total deposition of sulphur and nitrogen in South, North and North-East Estonia, although in some Northern and North-Eastern areas pollution endurance limits have been exceeded.  相似文献   

14.
An analysis of both the current levels and general trends of two major air pollutants (smoke and SO2) for the County of Merseyside has been attempted. The difficulties associated with use of the National Survey monitoring sites (as published by the Warren Spring Laboratory) to resolve values and trends on this county scale are described. The highly flexible nature of the co-operating body scheme by which most air pollution monitoring in the U.K. is undertaken results in extremely ‘noisy’ data especially in the light of continuing improvements in air quality and the changing emphasis and priorities in pollution control programs. It is also emphasized that evaluation of meteorological variables on this spatial scale is extremely questionable although it appears that temperatures can be well represented by a typical station's record. All discussions of air pollutants: levels, control and dispersion on the county-scale should be treated with considerable caution.  相似文献   

15.
Long-range tropospheric transport of acidic and non-acidic contaminants into or across the Pacific Ocean from sources originating in Pacific Rim countries and beyond (trans-Pacific air pollution, for short) is an emerging international environmental issue. This paper provides a definition of trans-Pacific air pollution; summarizes some of the scientific evidence for what seems to be the dominant pollutant pathway in the Asia-Pacific region, transport on westerly winds from Asia to North America; discusses a recent conference on trans-Pacific air pollution; and analyzes some of the political implications of the problem. Evidence for trans-Pacific air pollution comes from three main sources: observational data, computer simulations, and research on concentrations of pollutants in various media. Trans-Pacific air pollution is of political consequence. There may be wide-ranging physical and chemical effects if the relatively pristine air of the Pacific troposphere is altered. Domestic air quality along the west coast of North America may be altered. Degradation of the Arctic environment may be accelerated. The issue reinforces the need for greater international cooperation on environmental issues in the Asia-Pacific region.  相似文献   

16.
Health effects of air pollution in Asia have been assessed as part of a programme on Regional Air Pollution in Developing Countries. The impacts of air pollution on health have been studied in North America and Europe for many decades, but research on effects on health in developing countries is less advanced. A key question is whether the dose-response models that are based on research conducted in developed countries can be applied to exposures to air pollution in developing countries. The study considered this issue and examined the factors that may lead to either increased sensitivity or increased human tolerance of air pollutants. It is suggested that although there are factors in developing countries that may increase or decrease human sensitivity to air pollution, overall, a similar range of sensitivity can be expected by individuals in these countries responding to the same effective dose as those in developed countries.  相似文献   

17.

In major cities, air quality is of significant concern because of its negative effect on the health of the region’s living conditions, climate, and economy. Recent studies show the significance of the data on microlevel pollution which includes severe air pollutants and their impacts on human. Conventional methods of measuring air quality need skilled personnel for accurate data measurement that are based on stationary and limited measuring station networks. However, it is costly to seize the spatio-temporal variability and to recognize pollution hotspots that are necessary to develop real-time exposure control strategies. Due to the restricted accessibility of information and the non-scalability of standard techniques for air pollution monitoring, a real-time system with both higher spatial and temporal resolution is crucial. In recent times, unmanned aerial vehicles (UAVs) mounted with various sensors have been implemented for on-site air quality surveillance as they can offer new methods and research possibilities in air pollution and emission tracking, as well as in the study of environmental developments. An extensive literature review has been conducted, and it was observed that there are types of UAVs and types of sensors that are used for air quality monitoring for the parameters like CO, SO2, NO2, O3, PM2.5, PM1.0, and black carbon. Low-cost wireless sensors have been using for monitoring purpose in the past studies, and when results obtained are validated with the stationary monitoring instruments, the coefficient of correlation (R2) is found to be varied from 0.3 to 0.9. The difficulties, however, are not just technical, but at present time, policies and laws, which vary from country to country, symbolize the major challenge to the extensive use of UAVs in air quality/monitoring studies.

  相似文献   

18.
Critical loads are estimated in the UK by the Department of Environment's Critical Loads Advisory Group and sub-groups. The Mapping and Data Centre at ITE Monks Wood acts as the National Focal Centre for the UNECE programme for mapping critical loads. The centre is responsible for the generation of UK data sets and their application for national and European purposes. To make effective use of these data, it is necessary to draw upon other environmental data and examine the issues of scale, uncertainty and the way that data are presented. This paper outlines the methodologies which have been employed to derive national maps. Early critical load maps were not vegetation specific, but now critical loads for acidity and for nutrient nitrogen for soils, critical levels maps for ozone and sulphur dioxide, and sulphur deposition maps, have been generated on a vegetation or ecosystem specific basis. These have been used to derive a number of different types of critical load and exceedance maps. The results show the importance of the method selected and the data used for the interpretation. The visualisation of critical loads and the corresponding exceedance data is an important aspect in producing information for pollution abatement strategies.  相似文献   

19.
Earlier in this century, a number of severe episodes clearly demonstrated that air pollution can affect human health; these included documented increases in mortality and morbidity. Although health was clearly affected during these episodes and acidity is a candidate for the responsible agent, it has been difficult to ascertain which agents were involved. In the past several years extensive research was launched to learn the significance of acidic aerosols on human health. The question of a health threat from acid aerosols was first raised by epidemiology studies, but results of the body of epidemiological evidence collected to date have been mixed. Even when a study finds evidence of a response to exposures involving high ambient acidity levels, it is usually difficult to know which agent or agents are responsible for causing the effects noted. High levels of acidic aerosols are nearly always accompanied by high levels of other air pollutants which may have known or suspected effects on the respiratory tract. For this reason, an understanding of the potential mechanisms of acid aerosol health effects needs supporting evidence from the laboratory, where exposures to various agents can be controlled. To date, this supporting evidence includes demonstration of physiological responses at acidity levels greater than those that exist in the ambient environment. A limited number of studies have considered responses at levels more characteristic of ambient exposures; these studies demonstrate little physiological response, probably due to the airways' ability to buffer acidity at low concentration. Although there is some evidence of impaired mucociliary clearance and modest changes in lung function, there is no evidence of airway inflammation or altered non-specific bronchial responsiveness as a result of acid aerosol exposure. The possibility that acid aerosols may potentiate responses to other pollutants remains a subject of interest. The potential existence of a group of individuals who are exquisitely sensitive to low acid concentrations requires further investigation. Recent epidemiology results are broadening the perspective from a focus on acidity per se to a focus on fine particulate matter, of which particulate acidity is but a subset. These studies find a consistent statistical association between various health responses, including mortality, and ambient measures of particulates, even at locations where levels of acidity are very low and at locations where current U.S. air quality standards are satisfied. There is at present no biological explanation for these associations.  相似文献   

20.
Israel is a participant in the Earth Resources Technology Satellite Program (ERTS). The imagery of Israel and vicinity taken by the Multi Spectral Scanner of the ERTS-1 Satellite has been the subject of analysis in a multidisciplinary research program. The objectives of the program are mapping of agricultural crops, mainly wheat and orange groves, mapping of natural vegetation, and studies for Israeli hydrology, arid regions research, geology, and oceanography. Cases of water, air, and soil pollution have been observed in the imagery on several dates, and are reported in this paper. These are: oil slicks in the Gulf of Suez and possibly near Haifa; smoke plumes, extending over some 100 km in a nearly straight line along the Gulf of Suez, and soil pollution caused by copper mine effluents in the Arava Valley in Israel. The images of these cases of pollution are presented and ‘space signatures’, i.e., the radiometric spectral characteristics of these cases of pollution as seen from space are also given.  相似文献   

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