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1.
Nitrogen oxides emissions in Asia during the period 1990–2020 due to anthropogenic activity are presented. These estimates are based on the RAINS-ASIA methodology (Foell et al., 1995, Acid Rain and Emission Reduction in Asia, World Bank), which includes a dynamic model for energy forecasts, and information on 6 energy sectors and 9 fuel types. The energy forecasts are combined with process emission factors to yield NOx emission estimates at the country level, the regional level, and on a 1 degree by 1 degree grid. In 1990 the total NOx emissions are estimated to be ∼19 Tg NO2, with China (43%), India (18%) and Japan (13%) accounting for 75% of the total. Emissions by fuel are dominated by burning of hard coal and emissions by economic activity are dominated by the power, transport, and industrial sectors. These new estimates of NOx emissions are compared with those published by Hameed and Dignon (1988, Atmospheric Environment 22, 441–449) and Akimoto and Narita (1994, Atmospheric Environment 28, 213–225). Future emissions under a no-further-control scenario are also presented. During the period 1990–2020 the NOx emissions increase by 350%, to ∼86 Tg NO2. The increase in NOx emissions by sector and end-use varies between countries, but in all countries this increase is strongest in the power and transport sectors. These results highlight the dynamic nature of energy use in Asia, and the need to take the rapid growth in NOx emissions in Asia into account in studies of air pollution and atmospheric chemistry.  相似文献   

2.
In 1997, the United States National Ambient Air Quality Standard (NAAQS) for ozone was revised from a 1-h average of 0.12 parts per million (ppm) to an 8-h average of 0.08 ppm. Analysis of ozone data for the ensemble of the contiguous United States and for the period 1980–1998 shows that the average number of summer days per year in exceedance of the new standard is in the range 8–24 in the Northeast and in Texas, and 12–73 in southern California. The probability of exceedance increases with temperature and exceeds 20% in the Northeast for daily maximum temperatures above 305 K. We present the results of several different approaches to analyzing the long-term trends in the old and new standards over the continental United States from 1980 to 1998. Daily temperature data are used to resolve meteorological variability and isolate the effects of changes in anthropogenic emissions. Significant negative trends are found in the Northeast urban corridor, in the Los Angeles Basin and on the western bank of Lake Michigan. Temperature segregation enhances the detection of negative trends. Positive trends occur at isolated sites, mostly in the Southeast; a strong positive trend is found in Nashville (Tennessee). There is some evidence that, except in the Southwest, air quality improvements from the 1980s to the 1990s have leveled off in the past decade.  相似文献   

3.
Selected organonitrogen, organophosphorus and organochlorine pesticides have been determined in precipitation samples collected at 10 sites in the Gdańsk region (northern Poland) over a period of one year (1998). Compounds which were detected most often included simazine (0.11-5.80 ng/l), fenitrothion (0.1-2.10 ng/l), chlorfenvinfos (0.1-1.30 ng/l), gamma-HCH (0.012-5.06 ng/l), heptachlor epoxide (0.05-3.28 ng/l) and aldrin (0.02-3.28 ng/l). The pesticide concentrations in precipitation samples revealed seasonal fluctuations, with higher concentrations observed during the application periods (June and July). The concentrations observed were also affected by the inflow of polluted air masses from the southwest. The total pesticide concentration in the precipitation samples was strongly related to the abundance of green areas in the vicinity of the sampling sites. A weak correlation was also found between the total concentration of organonitrogen and organophosphorus pesticides, and the total concentration of organochlorine pesticides in the samples collected.  相似文献   

4.
Environmental Science and Pollution Research - Moroccan employers have a strong responsibility for the safety and health of their employees in the workplace and for protecting them from the risk of...  相似文献   

5.
Ozone data at the Jungfraujoch Observatory (3580 m asl) in the Swiss Alps have been recorded continuously since 1986 in the framework of the Swiss National Air Pollution Monitoring Network (NABEL), operated by the Swiss Federal Laboratories for Materials Testing and Research (EMPA). The long-term ozone record (1988–1996) was examined with regard to potential inhomogeneities using Zugspitze (2960 m asl), a neighbouring alpine site in Germany, as a reference site. The Alexandersson test (for shift) and the Easterling–Peterson test (for trend and shift) were applied to a difference times series, calculated from monthly ozone means at Jungfraujoch and Zugspitze. The Alexandersson test revealed a significant shift discontinuity in November 1989 and the Easterling–Peterson test a trend discontinuity in September 1991. It is assumed that the shift discontinuity may be related to an instrument change, but there is not firm evidence due to lack of detailed information from the instrumental history in the earlier years of the ozone record at Jungfraujoch. Monthly ozone means at Davos (1640 m asl) in eastern Switzerland indicate that part of the trend discontinuity in September 1991 may be of natural origin. Adjustment of the monthly ozone means at Jungfraujoch for the observed shift discontinuity removed the inhomogeneity in November 1989, and reduced the trend discontinuity by a factor of 4.8. A trend analysis on both adjusted (homogenised) and unadjusted monthly ozone means (1988–1996) at Jungfraujoch showed no statistically significant linear trend. The boundaries encompassing the true linear trend are indicated by two linear regression calculations on both adjusted and unadjusted data. Trends in the cold season are positive albeit not significant. The only statistically significant trends are found in October, December, and February for the adjusted data.  相似文献   

6.
In April 1998, a holding lagoon containing pyrite ore processing waste rich in arsenic, failed and released 5-6 million m(3) of highly polluting sludge and acidic water. Over 2700 ha of the internationally important Do?ana National and Natural Parks were contaminated. The area of Natural Park to sustain the greatest impact was known as the Entremuros. This paper presents 0-5 cm soil monitoring data from the Entremuros, from sampling campaigns 6 and 18 months after the disaster; as well as macrophyte root, rhizome and stem data from samples taken 18 months after the spill. Results show a clear, decreasing, north-south arsenic soil pollution trend, both 6 and 18 months after the spill, and suggest a small reduction in total soil arsenic levels occurred over time; although a significant increase in extractable arsenic is also noted. The two macrophytes (Typha dominguensis and Scirpus maritimus) studied herein are not accumulating arsenic in stem parts, however, accumulation of arsenic on iron plaque on the roots of these plants may be occurring. Further work is recommended in order to determine the ecotoxicological significance of this process in relation to the avian food-chains of Do?ana, and elsewhere.  相似文献   

7.
Environmental Science and Pollution Research - Air and water quality in urban centers are summited to pollution from different sources, such as industrial activities, traffic, and wastewater...  相似文献   

8.
A laboratory study was conducted to test the ability of various sorbents to remove vapor-phase atmospheric carbonaceous materials otherwise retained by sorption on quartz filters, a ‘positive artifact’ in sampling atmospheric particulate C. A dual quartz filter strategy, in which the C recovered from the after-filter is used to correct for the positive artifact, was also assessed. Sorbents such as activated Al2O3 and quartz fiber can reduce by up to 60% the positive artifact in sampling at 20 ℓ min with 47-mm Pallflex 2500 QAO quartz filters. On the assumption, defended herein, that a quartz fiber profilier was unlikely to influence the ratio of C retained by sorption on downstream tandem quartz filters, the dual filter strategy permitted correction for this positive artifact within, on average, 12%. Conclusions from an initial study suggesting extensive loss by volatilization of previously collected particulate C are reassessed.  相似文献   

9.
Lindström G  Rosberg J  Arheimer B 《Ambio》2005,34(7):533-537
The HBV-NP model is a newly developed water quality model that describes the turnover and fluxes of both nitrogen and phosphorous. It is based on the conceptual precipitation/runoff HBV model. The HBV-NP model was applied for simulation of nitrogen for the R?nne? catchment in southern Sweden. The catchment was divided into 64 subcatchments in the model. Discharge measurements from six stations and nitrogen measurements from 12 stations were used in the calibration of parameters in the model. Eight automatic calibrations were performed with different combinations of time periods, objective functions, and levels of the nitrogen load in the model. A regionally extended interpretation of the Nash-Sutcliffe R2 criterion was used in the calibration. In the evaluation of the criterion, the errors were summed over both time steps and sampling points. Scenario simulations of combined measures for reduction of nitrogen load into the sea by 30% were thereafter performed with the eight sets of parameters established by calibration. The model parameters were not uniquely defined by the calibration. However, the simulated relative reduction of nitrogen load into the sea was relatively insensitive to the choice of parameter set, given the available input sources, variables, and data.  相似文献   

10.
The Bulgarian dispersion model 'Eulerian Model for Air Pollution' (EMAP) is used to estimate the sulphur pollution over the Balkan region for the period 1995–2000. A subdomain of the European Monitoring and Evaluation Programme (EMEP) grid is chosen containing 12 countries. The computational grid in this domain has a space step of 25 km, twice as fine as the EMEP grid. The former operational DWD 'Europa-Model' is used as meteorological driver. The source input is the official EMEP emission data. Monthly calculations are made having the last moment fields from the previous month as initial conditions for the next one. The boundary conditions are set to zero, so the influence of other European sources is not accounted for in this study. According to the EMEP methodology, multiple runs are made setting every time the sources of various countries to zero. The impact of every country in the pollution of all others is estimated.  相似文献   

11.
The effect of buildings on the dry deposition of dust particles was investigated in Be'er-Sheva, a desert city with about 140,000 inhabitants in southern Israel, and at two reference points in the surrounding rural area. The mineral and chemical composition of dust sampled at all sites was similar, reflecting the composition of the local loess soil, its likely origin. However, dust deposited in the traps set up in the vicinity of buildings in the city was significantly coarser than the dust which accumulated in similar traps at exposed sites in the countryside. The amount of dust (by weight) in the urban dust traps was on an average more than twice the amount deposited in the rural area. The differences in grain-size distribution and quantity of dust are attributed to the properties of the urban wind field and to various effects of human activity in the city.  相似文献   

12.
Levels of eight PCB congeners and thirteen organochlorine pesticides were measured in eggs sampled at four yellow-legged gull colonies from the Aegean Sea (NorthEastern Mediterranean) in 1997. There were no significant differences among colony areas in the median concentrations in any of the pollutants whereas cluster analyses did not generally reveal reasonable pollution patterns. The maximum concentrations of four congeners were found at Kinaros colony and of nine compounds were found at Lipsos colony. Fingerprints in both groups were similar in all areas. Of PCBs, congener 28, 118, 138, 180 and of pesticides beta-BHC and 2,4'-DDD were prominently dominant suggesting a particular pollution pattern in this region. Statistically significant correlations were found between most of the higher PCBs in all areas studied. The DDT metabolites correlated mostly with other OCs. We suggest that regional pollution by both groups is not adequately reflected in the eggs of this gull probably due to its extensive scavenging habits and, though information is needed from more colonies, it seems to be a poor biomonitor for organochlorines in this region.  相似文献   

13.
14.
In a warming climate, permafrost is likely to be significantly reduced and eventually disappear from the sub-Arctic region. This will affect people at a range of scales, from locally by slumping of buildings and roads, to globally as melting of permafrost will most likely increase the emissions of the powerful greenhouse gas methane, which will further enhance global warming. In order to predict future changes in permafrost, it is crucial to understand what determines the presence or absence of permafrost under current climate conditions, to assess where permafrost is particularly vulnerable to climate change, and to identify where changes are already occurring. The Tornetr?sk region of northern sub-Arctic Sweden is one area where changes in permafrost have been recorded and where permafrost could be particularly vulnerable to any future climate changes. This paper therefore reviews the various physical, biological, and anthropogenic parameters that determine the presence or absence of permafrost in the Tornetr?sk region under current climate conditions, so that we can gain an understanding of its current vulnerability and potential future responses to climate change. A patchy permafrost distribution as found in the Tornetr?sk region is not random, but a consequence of site-specific factors that control the microclimate and hence the surface and subsurface temperature. It is also a product of past as well as current processes. In sub-Arctic areas such as northern Sweden, it is mainly the physical parameters, e.g., topography, soil type, and climate (in particular snow depth), that determine permafrost distribution. Even though humans have been present in the study area for centuries, their impacts on permafrost distribution can more or less be neglected at the catchment level. Because ongoing climate warming is projected to continue and lead to an increased snow cover, the permafrost in the region will most likely disappear within decades, at least at lower elevations.  相似文献   

15.
Quantitative assessments have long been used to evaluate the condition of the natural environment, providing information for standard setting, adaptive management, and monitoring. Similar approaches have been developed to measure environmental governance, however, the end result (e.g., numeric indicators) belies the subjective and normative judgments that are involved in evaluating governance. We demonstrate a framework that makes this information transparent, through an application of the Freshwater Health Index in three different river basins in Latin America. Water Governance is measured on a 0–100 scale, using data derived from perception-based surveys administered to stakeholders. Results suggest that water governance is a primary area of concern in all three places, with low overall scores (Guandu-26, Alto Mayo-38, Bogotá-43). We conclude that this approach to measuring governance at the river basin scale provides valuable information to support monitoring and decision making, and we offer suggestions on how it can be improved.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01407-8) contains supplementary material, which is available to authorized users.  相似文献   

16.
Environmental Science and Pollution Research - This study aimed to examine the role of effective employee training in the sustainable growth and corporate social responsibility of hotels during the...  相似文献   

17.
Emission reductions were mandated in the Clean Air Act Amendments of 1990 with the expectation that they would result in major reductions in the concentrations of atmospherically transported pollutants. This paper investigates the form and magnitude of trends from 1989 to 1995 in atmospheric concentrations of sulfur dioxide, sulfate, and nitrogen at 34 rural sites in the eastern US. Across all sites, there is strong evidence of statistically significant declining trends in sulfur dioxide (median change of -35%) and sulfate concentrations (median change of -26%). In general, trends in nitrogen concentrations were not as pronounced (median change of -8%) as trends in the sulfur compounds. A regional estimate of trend for a cluster of sites in the Ohio River valley showed close correspondence between declining sulfur dioxide concentrations (-35%) and changes in sulfur dioxide emissions (-32%) in this region.  相似文献   

18.
There is an ongoing discussion whether in the environmental risk assessment for chemicals the so called 'deterministic' approach using point estimates of exposure and effect concentrations is still appropriate. Instead, the more detailed and scientifically sounder probabilistic methods that have been developed over the last years are widely recommended. Here, we present the results of a probabilistic effect assessment for the aquatic environment performed for the pesticide methyl parathion and compare them with the results obtained with the common deterministic approach as described in the EU Technical Guidance Document. Methyl parathion was chosen because a sufficient data set (acute toxicity data for about 70 species) was available. The assumptions underlying the probabilistic effect assessment are discussed in the light of the results obtained for methyl parathion. Two important assumptions made by many studies are: (i) a sufficient number of ecologically relevant toxicity data is available, (ii) the toxicity data follow a certain distribution such as log-normal. Considering the scarcity of data for many industrial chemicals, we conclude that these assumptions would not be fulfilled in many cases if the probabilistic assessment was applied to the majority of industrial chemicals. Therefore, despite the well-known limitations of the deterministic approach, it should not be replaced by probabilistic methods unless the assumptions of these methods are carefully checked in each individual case, which would significantly increase the effort for the assessment procedure.  相似文献   

19.
The products of the OH radical-initiated oxidation of dimethyl sulphide (DMS) have been investigated as a function of temperature (284, 295, and 306 K) and different initial NOx (NO+NO2) concentrations: initial NO was varied between 434 and 2821 ppb and NO2 between 135 and 739 ppb. The experiments were performed at 1000 mbar total pressure in synthetic air using the photolysis of H2O2 as the OH-radical source and FT-IR spectroscopy to monitor reactants and products. The major sulphur-containing products identified were SO2, dimethyl sulphoxide (DMSO), dimethyl sulphone (DMSO2), methane sulphonic acid (MSA), methane sulphonyl peroxynitrate (MSPN) and OCS. The variation of the product yields with temperature and NOx concentration are consistent with the occurrence of both addition and abstraction channels in OH radical-initiated oxidation of DMS. Distinct trends in the yields of the various products have been observed as a function of temperature, initial NOx conditions and also reaction time as NO is consumed in the system. Increasing the initial NO concentration was found to depress the DMSO, SO2 and OCS formation yields and enhance those of DMSO2, MSA and MSPN. The yield–time behaviour of DMSO2 is supportive of a formation mechanism involving addition of O2 to a (CH3)2SOH adduct, formed via the addition channel, followed by sequential reactions with NO and O2. The mechanisms controlling the concentration–time profiles of the individual products under the present experimental conditions are discussed in detail and consideration is given to possible implications for the photo-oxidation of DMS under ambient conditions.  相似文献   

20.
Environmental Science and Pollution Research - Diabetes is one of the most comprehensive metabolic disorders and is spread across the globe. The data from IDF Diabetes Atlas and National Diabetes...  相似文献   

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