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1.
Atmospheric air pollution levels and long-term effects on the environment caused by simultaneous presence of SO2 and oil shale alkaline fly ash during the last five decades (since 1950) were investigated. The annual critical value of SO2 for forest (20 µg m?3) was surpassed in 1% (～35 km2) of the study area where the load was 30–40 µg m?3. No effect of long-term SO2 concentrations of up to 10–11 µg m?3 (0.5-h max up to 270 µg m?3) and simultaneous fly ash loads of up to 95 µg m?3 (1000 µg m?3) on the growth and needle longevity of Pinus sylvestris was established. The yearly deposition (average load up to 20–100 kg S ha?1) was alkaline rather than acidic due to an elevated base cation deposition in 1960–1989. Since 1990, the proportion of SO2 in the balance of components increased: about 70–85% of the total area was affected while the ratio of annual average concentrations of SO2 to fly ash was over 1. The limit values of fly ash for Sphagnum mosses and conifers in the presence of SO2 are recommended.  相似文献   

2.
Daily average SO2 concentrations were measured during August 1999–September 2000 period in the mountains around Izmir. Sampling devices to collect integrated daily SO2 samples were located at four different sites. These sites were Yamanlar Mountain in the north, Tekketepe height of Karabelen Mountain in the south, and two mountain villages (Kiziluzum and Bespinar) located east of Izmir. Samples were analyzed by using standard methods. Maximum daily SO2 concentrations up to 433 μg m-3 were found with the average values ranging between 75–135 μg m-3 per day at the four mountain stations. Annual mean values were above the threshold levels acceptable for the health of trees. It is concluded that such high SO2 pollution might have caused the noted decline in the forests.In order to decide the sources of such high levels of pollution on the forested mountains, trajectory analyses were carried out. Results obtained at Tekketepe station are given in this article and they point to the fractional contributions of dense industrial areas around Izmir, to the forested heights of Tekketepe. Local topography and location of industrial zones around the city are seen to have a strong effect on the deteriorated air quality over the mountains. The annual and seasonal averages and ten maximum daily measurements at the Tekketepe sampling site indicate that the highest contribution to the deterioration of air quality is associated with the northerly wind sectors.  相似文献   

3.
Long term continuous monitoring measurements of urban atmospheric concentrations of O3, NO2, NO, and SO2 were performed for the first time in Ciudad Real, a city in central-southern Spain. The measurements were carried out using the differential optical absorption spectroscopy (DOAS) technique, with a commercial system (OPSIS, Lund-Sweden), covering the summer and winter seasons (from 21st July 2000 to 23rd March 2001). Mean levels of O3, NO2 and SO2 monitored during this period were: 27 μg m?3, 50 μg m?3 and 7 μg m?3 respectively. The highest hourly averaged value of O3 (160 μg m?3) was measured during the summer period, while NO2 was enhanced in wintertime (highest values 90 μg m?3). In the coldest period, when central heating installations were operating, SO2 showed maximum levels of 20 μg m?3. The daily, weekly and seasonal analysis of the data shows that photochemical air pollution dominates in this urban atmosphere and is strongly influenced by levels of motor traffic and domestic heating system emissions. These measurements were compared with other studies in Spain and Europe. Also, the long path averaged DOAS measurements were compared with in situ observations made in Ciudad Real, from 23rd August 2000 to 25th September 2000, using a mobile air pollution control station. All gas concentrations reported in this paper are below the WHO guidelines and the different thresholds introduced by the European Environmental Legislation.  相似文献   

4.
Needles of Scots pine (Pinus sylvestris L.) from 25 and 40 sampling plots in southern and northern Finland, respectively, that had earlier been analysed for total sulphur concentration (St) were reanalysed for foliar sulphate sulphur (SO4–S) and total nitrogen (Nt). Organic sulphur content (So) was calculated as the difference between St and SO4–S. Current (c) and previous-year (c+1) needles were collected from southern Finland in December 1989 and c – c+2 needles from northern Finland in September-October 1990/September 1992. The results show that the St concentration and St/Nt ratio in Scots pine needles are good indices of dry deposition of SO2 in general, while SO4–S concentrations and SO4–S/So ratios can be used in areas with low N supply from the soil and/or low wet deposition of N. The normal St concentration in needles of Scots pines growing on a podzol with low N supply is considered to be 500–700 μg g-1 and that of SO4–S 100–200 μg g-1. An increase of 100 μg g-1 in needle St may be attributed to a rise of 1.4 μg m-3 in ambient SO2 concentration in areas with relatively low SO2 concentrations (>15 μg m-3). A critical level of 5 μg m-3 as an annual and growing season mean is proposed for forestry in northern Europe (north of 60°N).  相似文献   

5.
Total S concentrations of Scots pine (Pinus sylvestris L.) needles studied in the Finnish subarctic (66–70°N, 24–30°E) in 1990/1992 ranged from 573 to 1153 μg g-1. Levels were found to be ≈ 900 μg g-1 (i.e. 1.3–1.8 times the ‘normal’ level of 500–700 μg g-1) in areas where the long-term ambient SO2 concentration was ≈ 2–5 μg m-3, particulate SO4 2- ≈ μg m-3 and total S deposition ≈ 0.5 g m-2. A statistically significant increase in needle total S concentrations was found towards the east, i.e. towards the smelters of the Kola Peninsula in Russia, which emit SO2. The increase in needle total S concentrations to over 900 μg g-1 close to the Russian border is thought to result mainly from exposure to high short-term SO2 concentrations. The results also suggest that wintertime S deposition may have an impact on the needle total S content. It is suggested that the UNECE long-term critical level of 15 μg SO2 m-3 for forestry in boreal and high mountain climates in Europe is too high for the pine forests in the extreme north, where the proportion of dry-deposited S may be 60–80%.  相似文献   

6.
Sulphur budgets for Ontario, Quebec and the Atlantic Provinces have been computed using the Long-Range Transport of Air Pollutants model (LRTAP) which has been developed within the Atmospheric Environment Service of Canada. Meteorological data from 1978 and a North American SO2 emissions inventory for 1970–1974 form the basic model input. The S budgets for the eastern Canadian regions were computed for large-scale emission scenarios. The budget shows the trans-boundary mass transport, S deposition and S concentrations within the regions for each scenario and shows the relative contribution to the deposition in each region. For eastern Canada, the model shows an annual S transboundary input of about 2 Tg S, an emission of about 1.8 Tg S, a deposition of about 2.4 Tg S and an output of about 1.4 Tg S. For southwestern Ontario, the model shows an annual average SO2 concentration of 25 to 30 μg m?3 (10 ppb), an annual sulphate concentration of about 8 μg m?3, an annual wet deposition of S of about 15 kg S ha?1 and an annual sulphate concentration in precipitation of about 5 to 6 mg l?1.  相似文献   

7.
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   

8.
The colony growth of some phylloplane fungi of wheat viz. Alternaria alternata, Aspergillus favus, Amiger, Cladosportium cladosporioides, Curvularia lunata, Drechslera australiensis, Epicoccum purpurascens, Fusarium oxysporum, Penicillium chrysogenum and P. citrinum were studied in chamber fumigation experiments exposed to 2669 ± 105 μg SO2 m?3 and 708.33 ± 55 μg NH3 m?3 air, separately, for 10, 30 and 60 min. The colony growth of all the test fungi was significantly (P=0.01/0.005) inhibited on prolonged period of SO2/NH3 exposure. However, some of the test fungi namely A. favus, A. niger, E. purpurascens and F. oxysporum showed growth stimulation after 10 min exposure of SO2. Similarly, the growth of C. lunata and F. oxysporum increased only after 10 min exposure of NH3. The inhibitory effect of SO2/NH3 was directly correlated with the exposure times.  相似文献   

9.
SO2 concentrations have been measured for one year at forty-five locations throughout Asia using passive samplers. Duplicate samples were exposed at each site for one month intervals. The sites were selected to provide background information on the distribution of SO2 over wide geographical regions, with emphasis on the regional characteristics around areas estimated to be sensitive to sulfur deposition. The annual mean values ranged from less than 0.3 μg/m3 at Tana Rata, located at 1545 m on the Malaysia Peninsula, Lawa Mandau, (Borneo) Malaysia, and Dhankuta, Nepal, to values greater than 20 μg/m3 at Luchongguan (Guiyang) China, Babar Mahal, Nepal, and Hanoi, Vietnam. In general high concentrations were measured throughout China, with the highest concentrations in the heavy industrial areas in Guiyang. The concentrations in east Asia around the Korea peninsula were ～5 μg/m3. The concentrations in the southeast Asia tropics were low, with no station in Malaysia and Indonesia having average concentrations exceeding 1.7 μg/m3. The observed SO2 concentrations were found to display a distinct seasonal cycle which is strongly influenced by the seasonality of winds and precipitation patterns.  相似文献   

10.
The SO2 emissions from the Kola Peninsula in Arctic Russia (totalling around 600 Gg(SO2) yr–1 at the beginning of the 1990s) produce an atmospheric SO2 concentration gradient to the northernmost Europe. This gradient covers the range from >50 g m–3 in the vicinity of the sources to 1 g m–3 in Finnish Lapland. In the present study, the measured sulphur concentrations in Scots pine needles were compared with the estimated distribution of atmospheric SO2. The total sulphur concentrations in the needles ranged from 741 to 2017 mg kg–1. Strongly elevated concentrations (> 1200 mg kg–1) were found within 40 km from the smelters corresponding to an area where the annual mean atmospheric SO2 concentration exceeded 10 g m–3. The foliar sulphur concentrations (total, organic and inorganic) show a high correlation with the estimated mean SO2 concentration distribution in the air. Consequently the foliar sulphur concentrations reflected the atmospheric sulphur load well. The data presented here show that uptake via stomata is an important deposition pathway also in the arctic conditions with a short growing season.  相似文献   

11.
Seedlings of six Picea abies provenances were exposed to Al, SO2 and A1+SO2 for 12 weeks. A molaric Ca/Al ratio of 0.05 was chosen by using 1.68 mM Al. On the average, concentration of SO2 was 335 μg m?3. Shoot and root growth were measured and needle discoloration was scored for different pollution regimes. Plant response to different environmental stresses differed significantly among the provenances used and showed marked provenance x treatment interactions. It is noteworthy that the high intraspecific variation of the traits investigated could cause misleading conclusions in nongenetic studies if inappropriate plant material is employed.  相似文献   

12.
PM2.5 and PAHs bound to PM2.5 were investigated in downtown Bologna, from January to June 2003, in order to determine the burden of the fine fraction in the aerosol of a typical urban environment of the Po Valley, a critical area in Northern Italy in terms of atmospheric pollution. The sampling campaign was divided into three parts: a winter sub-campaign, an intermediate campaign where PM2.5 and PM10 were simultaneously sampled and which identified PM2.5 as the major component of PM10, and a summer sub-campaign. Critical concentrations of both PM2.5 and PAHs were observed in winter time; for example, in January 2003 the mean value for the 24-h average PM2.5 concentration was 58 μg/m3, much higher than the annual arithmetic mean of 15 μg/m3 established by the US ambient air quality standard (NAAQS). Correspondingly, the mean value for benzo[a]pyrene (BAP) in PM2.5 was 1.79 ng/m3, again higher than the annual mean of 1 ng/m3, required by European regulations for BAP in PM10. In summer time the BAP concentration considerably decreases to 0.10 ng/m3 as the likely effect of photolysis and dilution on a higher boundary layer; PM2.5 decreases too, but the mean concentration (22 μg/m3) is still higher than the NAAQS value. Further analysis included TEM microscopy of collected particles and correlations between PM2.5, PAHs and gases (benzene, O3, CO, NO2, SO2). All these observations identified on-road mobile sources as the main source of emissions and, in general, of the poor air quality level in the city of Bologna.  相似文献   

13.
Erratum     
OLGA RIGINA and ALEXANDER BAKLANOV: Trends in sulfur emission-induced effects in northern Europe. Water, Air, and Soil Pollution 105 (1–4): 331–342, 1998. Figure 2 was mistakenly put mirrored. The correct Figure 2 is printed below. SO2 emission from the Severonickel (at Monchegorsk) and Pechenganickel (at Nickel and Zapolyarni) smelters and total for the Kola Peninsula (after the Murmansk Regional Committee of Nature Protection data). The correct legend for Figure 10 should read: Figure 10. Average annual SO2 concentrations μg m-3) at the monitoring stations Svanvik and Holmfoss in the Russian-Norwegian border area and SO2 emission from the Pechenganickel smelter (kt yr-1) for 1980–1995 (updated after Sivertsen et al., 1994).  相似文献   

14.
Sulfur transport and deposition in Asia, on an annual andseasonal basis, is analyzed using the ATMOS model. Calculationsare performed for two complete years (1990 and 1995). Deposition amounts in excess of 0.5 g S m-2 yr-1 are estimated for large regions in Asia, with values as high as 10 g S m-2 yr-1 in southeastern China. Annual averaged SO2 concentrations in excess of 20 μg SO2 m-3 are calculated for many urban and suburban areas ofeastern China and S. Korea, with an average of 5 μg SO2 m-3 over most of the emitter regions. Sulfur deposition by major source categories is also studied. Southeast Asia (Indonesia, Malaysia, Philippines, Singapore)receives ～25% of its sulfur deposition from shipping activities. Sulfur deposition from bio-fuel burning is significant for most of the underdeveloped regions in Asia. Volcanoes are a major source of sulfur emissions in the PacificOcean, Papua New Guinea, Philippines and Southern Japan. Sulfur deposition is shown to vary significantly throughout the year.The monsoons are found to be the largest factor controlling sulfur transport and deposition in the Indian sub-continent andSoutheast Asia. India receives over 35% of its total depositionduring the summer months. In East Asia, sulfur deposition isestimated to be 10% higher during summer and fall than winterand spring. Model results are compared with observations from a number of monitoring networks in Asia and are found to be generally consistent with the limited observations.  相似文献   

15.
This study investigated the relationship between exhaust emission from motorcycles and ambient air quality in Bangkok Metropolitan Region (BMR). The test result revealed that averagepollutant concentrations of the test motorcycles in terms of hydrocarbon, carbon monoxide and nitrogen dioxide were 8.38, 16.69 and 0.04 g km-1, respectively. The finding also indicated that two-stroke motorcycles emitted 1.5 and 5 times more carbon monoxide and hydrocarbon emission, respectively perkilometer driven than do four-stroke motorcycles. Four air sampling stations were strategically established to evaluate the air pollution problems in Bangkok arising from vehicle exhaust emission. Investigation was carried out to determine the correlation between average air pollutant concentration with different traffic configuration in each traffic zone of Bangkok Metropolitan Region (BMA) during peak/non peak hours, day/night times and weekday/weekend. The average concentrationsof PM10 particulate matter, carbon monoxide, nitrogen dioxide and sulphur dioxide in Bangkok street air were found tobe 84.33 μg m-3 (24 hr ave.), 7.05 mg m-3 (8 hr ave.), 56.74 μg m-3 (1 hr ave.) and 9.60 μg m-3 (24 hr ave.), respectively.  相似文献   

16.
Feng  Y. W.  Ogura  N.  Feng  Z. W.  Zhang  F. Z.  Shimizu  H. 《Water, air, and soil pollution》2003,145(1-4):95-107
This study was carried out from June 1995 to December 1998 to explore the current status of fluoride pollution, fluoride deposition, and sources of fluoride in Beijing. The mean fluorideconcentration of ambient aerosols in Beijing was 0.61 μg m-3, with a range of 0.08 to 1.61 μg m-3. The highest concentration (1.61 μg m-3) occurred in winterand was 20 times higher than in summer. This maximum concentration is to compare with annual volume-weighted averagefluoride concentration in Chongqing, Sichuan Province, an areaseriously polluted with fluoride. Fluoride pollution occurred inwinter in Beijing, because of the increased consumption of coal for heating, which resulted also in the highest dry deposition during winter and lowest in summer. The seasonal variations intotal fluoride were different from those of dry deposition. Thehighest total deposition was observed in summer, when 75% of theannual precipitation falls. Soil dust and coal combustion wereconsidered the main sources of fluoride in Beijing.  相似文献   

17.
Seedlings of closely related birch species Betula pendula and B. resinifera, which have moderate similarity in their phytochemical composition, were exposed to a SO2 concentration of 200 μg m-3 for 24 days to detect their sensitivity and possible induced changes in the amount of primary and secondary phytochemicals. The species deviated from each other in the production of biomass and phytochemicals. The SO2 pollution induced no changes in growth nor in the soluble sugar concentrations in the species. However, the chromatographic analyses showed the moderate reduction in the amount of antioxidative and defensive phenolics, i.e. myricitrin, (+)-catechin, 3,4'-dihydroxypropiophenone and proanthocyanidins in both birch species. These results indicate more pronounced sensitivity of secondary metabolism to SO2 pollution compared with primary metabolism, and the reduced tolerance of birches to other oxidative air pollutants as well as to herbivores in polluted environments.  相似文献   

18.
The research presented here represents a segment of a cumulative impact assessment of resource development in northeastern British Columbia. It considers point and area source emissions of sulphur and nitrogen oxides (SO2 and NO x , respectively), over a 2,156-km2 area. With the exception of open burning, all emissions are from Upstream Oil and Gas (UOG) sector sources (SO2, n?=?103; NO x , n?=?250; area, n?=?25). AERMOD View? was used to estimate the maximum potential concentration and deposition of these pollutants over 1-h, 3-h, 24-h, and annual averaging periods. Results are compared with various thresholds and limits from the policy and scientific literature to assess the potential cumulative effects of these pollutants. Of the thresholds employed, exceedances of the 1-h and 24-h NO x concentrations and the annual SO2 concentration are predicted. There were no predicted exceedances of annual deposition thresholds (i.e., ??Critical Loads??). Maximum predicted concentrations vary between compounds and are related to boundary layer stability, elevation, and distance from sources. Comparison with nearby monitoring data indicated that predicted concentrations were reasonable and that AERMOD provides a useful tool for approaching the potential cumulative impacts of air pollution from multiple sources. While the accuracy of Gaussian-based annual deposition estimates is questioned, model enhancements that could extend the application to more comprehensive assessments are suggested. Lastly, the implications of predicted threshold violations for forest ecosystems and local forest-dependent First Nations communities are discussed.  相似文献   

19.
The Arctic air mass is a unique meteorological feature of the northern hemispheric atmosphere. Possessing well-defined meteorological characteristics, it occupies not only the polar region but also a large fraction of the Canadian and Eurasian land masses during the period November to April. Poor pollutant removal by precipitation and dry deposition within the air mass and a strong transport pathway between Eurasian mid-latitudinal sources and the north, result in elevated levels of acidic anthropogenic aerosols and gases in the air mass during winter. In summer, weak north/south transport and strong pollutant removal between the Arctic and mid-latitudes and within the Arctic, results in lower airborne concentrations of acidic pollutants. Due to the presence of the relatively polluted Arctic air mass, ‘background’ air concentrations of SO4 =, SO2 and total NO3 ? are elevated in western Canada during winter. Typical mean monthly concentrations from December to March are 0.8 to 2.1, 1.0 to 2.4 and 0.1 ? 0.6 μg m?3, respectively. In the absence of the neutralizing influence of alkaline soil dust, the acidity of snow forming in western Canada during winter is expected to range from 5 to 20 μeq l ?1.  相似文献   

20.
During the period from 25 May 1991 to 30 May 1992 the atmospheric concentrations and depositions of oxides of sulfur were continuously measured in a suburban masson pine forest which is currently experiencing severe dieback, in Chongqing, China. The annual mean concentrations of SO2 and particulate SO4 2? were 220 μ g/m3 (77 ppbv) and 32 μ g/m3 respectively. The atmospheric concentrations of these sulfur compounds were high in late autumn and winter. The annual wet and dry depositions of sulfur to the forest as measured by throughfall and stemflow were 93.1 and 46.6 kgSha?1a?1 respectively. These depositions are among the highest level ever reported in the world. Althogh the cause of the dieback of the masson pine trees has not been unequivocally determined, it is probable that the direct impact of SO2 is more likely the cause than acid deposition.  相似文献   

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