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1.
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   

2.
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   

3.
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   

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.
The greatest sources of atmospheric emissions of SO2 in Estonia are caused by power plants (TP) which use oil shale. Since 1990 the amount of SO 2 discharges has continuously decreased due to fall in production of electric energy, and it was from TP as follows: in 1990–1991 about 180–200 thousand tons, in 1992 about 140 and in 1993–1994 about 100 thousand tons. In 1990 the annual mean emission intensity of SO 2 from all North-East (NE) Estonian pollution sources was fixed to be about 6.kg/s, with a maximum of 9.5–11 kg/s in winter period. In 1992–1993 the corresponding values were 3.5–4.6 and 5.1–6.8 kg/s. The single maximum concentrations (MC, per 30 min.) of SO 2 in the overground air layer would be in the ranges 25–450 μg/m 3 depending on emission intensity and wind parameters. The annual mean concentrations are below 25 μg/m 3 on the main territory, but may be up to 50–75 μg/m 3 near the power plants. In Kohtla-Järve town the annual mean values of 15.8–19.1 μg/m 3 and MC values of 271–442 μg/m 3 were fixed during 1991–1994 by automatic air monitoring system. Many arable lands, forest areas and wild-life preserves are subjected to relatively high sulphur precipitation loads, exceeding 0.5 g S/m2 per year, of which the role of emissions from local sources is about 60–95%. On the basis of air pollution concentration maps, the landscape of NE Estonia is classified into zones of high, moderate and low pollution level.  相似文献   

6.
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   

7.
Observations on gaseous and particulate pollutants were undertaken at four locations in the region of a thermal power plant (TPP), which is under construction at Tuticorin, south India. The predicted concentrations Of SO2 due to the emissions from the TPP and its possible impact on the inhabitants and climate in the downwind region were evaluated. Also, the predicted concentrations downwind of a Petrochemical Industrial Complex (PIC) located in the vicinity of the TPP were computed and compared with the measured concentrations. The predicted maximum concentration of SO2 at 6 km downwind of TPP is about 530 μg m?3 under most favourable wind conditions. The anticipated increase in SO2 due to the thermal power plant under construction may therefore be substantial. The predicted concentrations Of SO2, at a distance of 1.8 km downwind of the PIC, varied between 34 and 216 μg m?3 for wind directions ranging from 70 to 90° and for Pasquill stability category C. The plume would be over the observational site when the wind direction is 80°. The maximum measured concentration was 23 ug m?3. The discrepancy was due to the rapid fluctuations in the wind direction during the observational period over a wide range from 20 to 90°.  相似文献   

8.
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   

9.
The long range transport of mineral dust such as Yellow Sand (YS) is not restricted to the springtime periods in Northeast Asia. A YS phenomenon was observed during 25～27 January 1999, which was a remarkably distinctive episode in the occurrence time and intensity that had ever been observed in the wintertime in Korea. This YS event had a bi-modal temporal structure with the daily average concentrations of 210～349 µg m?3. The long-lasted second one followed the first arriving short and strong dust pulse. The dominant ion components were SO4 2?, NO3 ?, Ca2+ and Na+ with the concentration of 11.3, 7.6, 6.1 and 4.2 µg m?3, respectively during the passage of YS, compared to the corresponding concentrations of 4.1, 4.6, 0.4, and 1.2 µg m?3 after the passage of YS (AYS) over Korea. The mode diameter of these compounds of YS was around 4 µm, compared to 0.4～0.9 µm of AYS. Concentrations of SO4 2? and NO3 ? were found to be highly correlated with that of Ca2+ in the coarse mode during the YS event, whereas they were well correlated with NH4 + during the non-YS period.  相似文献   

10.
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   

11.
In order to estimate the influence of NH3 on a forest in a clean atmosphere, the quality of the atmosphere in Sumava, South-Bohemia, was determined in September–October 1988. In this period the NOX, SO2, and aerosol concentrations were extremely low. The N-input into the forest margin amounted to 10–15 kg ha?1 in these two months, based on a deposition velocity of 3 cm s?1 and an average concentration of 9 μg m?3 NH3. The maximum hourly average ozone concentrations were found to be 50 to 100 μg m?3. There exists a strong relation between the ambient NH3 concentration profiles and the stable occupation. The concentration inside the stables exceeded the no-adverse-effect level for cows of 7.6 mg m?3. This publication forms the basis for the estimation of the exposure of the forest to NH3 and the interpretation of the observed effects as published elsewhere (Mejst?ík et al., unpublished).  相似文献   

12.
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   

13.
This paper presents the simultaneous measurement of atmospheric concentration of gaseous NH3, SO2 and NO2, and particulate NH 4 + released from the mining activities of coal-mine area, Tirap colliery, Margherita (Assam). Gas samples were collected by impinger method and were analyzed colorimetrically. The vapor-phase concentration of NH3, SO2, and NO2 range between 4.7?C40.03, 1.47?C6.14, and 1.92?C2.40???g/m3. The NH 4 + concentration in PM10 and PM2.5 ranges between 0.02?C0.07 and 0.008?C0.03???g/m3, respectively. Moderately high concentrations of NH3 and SO2 on the first day were due to the coal-burning activity near the sampling site, while the low concentration of NO2 is due to less vehicle density near the sampling point. All the observed concentrations are below than those reported for the urban areas and the prescribed limit fixed by National Ambient Air Quality Standard, India. Study indicates that ammonia is the major neutralizing agent for sulfate and nitrate ions present in the particulate matter during mining activities.  相似文献   

14.
Abstract

Earlirose rice (Oryza sativa L. ) and Hawkeye soybeans (Glycine max L.) were grown in solution culture with A12(SO4)3 in concentrations of 0, 10‐6, 10‐5, 10‐4, 10‐3 M. Only at 10‐4 (slightly) and at 10‐3 M were there yield depressions due to Al. The threshold concentration of Al for toxicity was about 20 μg/g in rice shoots and about 30 μg/g in soybean leaves. The solution level necessary for these concentrations was 8 μg Al/ml. Plant concentrations which caused severe toxicity were 70 μg Al/g plant with 81 μg Al/ml solution. Most Al remained in roots, but leaves contained more than did stems of soybeans. The high Al decreased Fe, Cu, and Mn concentrations in shoots of rice and decreased Fe, Cu, and Zn in roots of rice. The high Al resulted in decreased Fe and Zn in leaves of soybeans. No Fe deficiency symptoms were present due to the high Al.  相似文献   

15.
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   

16.
Net mineralization of sulfur and nitrogen was studied in three Canadian Prairie soils using two commonly used incubation methods. In the open system technique, where the soils were leached periodically II.3–11.8 μ g SO2?4 -S g?1 soil was mineralized in 17 weeks. Little mineralization or a net immobilization of sulfur (from 1.4 to 1.3 μ g SO2?4-S g?1 soil) was observed in a closed system where the soils were left undisturbed throughout incubation. Changes in the specific activity of 35S-labelled soil solution sulfate during the closed incubation indicated that mineralization-immobilization processes were occurring simultaneously resulting in minimal net changes in CaCl2-extractable SO2?4 concentrations. The amounts of mineralized nitrogen (32.6–57.8 μg N g?1 soil) were found to be independent of the incubation method employed.  相似文献   

17.
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   

18.
Gillett  R. W.  Ayers  G. P.  Selleck  P. W.  Tuti  MHW  Harjanto  H. 《Water, air, and soil pollution》2000,120(3-4):205-215
Gas mixing ratios of SO2, NO2 and HNO3 and nitrate and sulfate concentrations in rainwater have beenmeasured at six sites in Indonesia. The sites, Jakarta, Serang,Cilegon, Merak and Bogor, in Java, and Bukit Koto Tabang inSumatra, provide a range of pollution regimes in Indonesia.Jakarta and Bogor are heavily polluted sites in Java, whereasBukit Koto Tabang is a clean air station in a relativelyunpopulated area on the west coast of equatorial Sumatra. At thesesites rainwater was collected daily and gas samples weeklyduring 1996. The other three sites Serang, Cilegon and Merakrepresent smaller regional towns in west Java. At these sitesrainwater samples were collected weekly from June 1991 untilJune 1992.The results show that Jakarta has the highest volume-weightedmean sulfate concentrations in rainwater while the lowest weremeasured at Bukit Koto Tabang. Volume-weighted mean nitrateconcentration was about 24 μeq L-1 at Jakarta and Bogor,significantly higher than the 0.8 μeq L-1 measured atBukit Koto Tabang.Sulfur dioxide mixing ratios ranged from 4–7 ppbv in Jakarta toan average of 1.3 ppbv at Bukit Koto Tabang. Nitrogen dioxidemixing ratio was highest in Jakarta averaging 28 ppbv comparedwith the background mixing ratio of 1.2 ppbv at Bukit KotoTabang. Using dry deposition velocities estimated during aseparate study in the similar conditions of Malaysia enabled drydeposition estimates of SO2, HNO3 and NO2.Results of estimated total acidic S and N deposition (wet anddry) were greater than 250 meq m-2 yr-1 at the Jakartaand Bogor sites compared with about 23 meq m-2 yr-1 atBukit Koto Tabang. At Jakarta and Bogor dry deposition accountedfor more than 50% of the total deposition estimates compared with about 20% at Bukit Koto Tabang. Such deposition rates arehigh when compared to critical loads estimated for Indonesia bythe RAINS-Asia model. In this model, critical loads in western Java and equatorial western Sumatra fall into one of twoclasses: 50–100 and 20–50 meq m-2 yr-1. Thus acidic deposition flux at Jakarta and Bogor wasfound to be above the predicted critical loads even for the moreacid insensitive soils.  相似文献   

19.
The Lizard Peninsula is an isolated area of unique and sensitive ecology and the occurrence of damaging ozone concentrations over the peninsula in spring challenges the successful sustainable management of the area. Ozone concentrations over Goonhilly Downs on the Lizard Peninsula in Cornwall were measured in spring 2002 using continuous monitoring and spatial mapping (diffusion tubes). Data obtained using a continuous ozone monitor (1/03/02 to 31/03/02) showed that the AOT40 5-day values were in a range from 2 to 800 μg m-3 hr (AOT40 is the sum of the differences between the measured hourly ozone concentration (μg m-3) and 80 μg m-3 (when the concentration exceeds 80 μg m-3) for the hours when global radiation exceeds 50 Wm-2). Contour mapping of ozone concentrations measured with diffusion tubes suggested that over a 2 km2 sampling area significant microscale variations were occurring with ozone concentrations ranging between 48–129 μg m-3 for one two-week period and 62–210 μg m-3 for the other.Unusually high diurnal variations in ozone concentrations were also observed at Goonhilly. It is thought that temperature inversions caused the entrapment of ozone at the surface level.  相似文献   

20.
Dentrification rates in two soils were assessed separately as a function of NO3? concentration while providing a constant initial glucose concentration, and as a function of glucose concentration while providing a constant initial NO3?-N concentration. Of the soils used, a Hanford sandy loam and a Coachella fine sand, the bacteria in the former produced higher rates of denitrification with a maximum loss of 1500 μg NO3?-N/ml day?1 as compared to a loss of 150 μg NO3?-N/ml day?1 from the latter. Rates of loss closely approximated Michaelis Menten kinetics in the Coachella sand, and Km values for glucose-C and NO3?-N were 500 μg/ml and 170 μg/ml, respectively. Rates of loss of NO3?-N from the Hanford soil did not approximate Michaelis-Menten kinetics, and this was attributed to failure to saturate enzyme systems in the denitrifying bacteria with glucose and nitrogen when each was held constant. C/N ratios around 2 appeared to provide the greatest rates of denitrification. High C/N ratios or high glucose concentrations (1.8 per cent) retarded denitrification, with fungal growth and a subsequent drop in pH occuring. A Pseudomonas was incubated aerobically for 24 h followed by a 72 h anaerobic incubation with nitrate as the sole nitrogen source at 0, 10, 50, 100, 250 and 500mg N/ml concentrations. Assimilatory nitrate reduction never exceeded 75 mg N/ml, and it was concluded that this mode of nitrate reduction is insignificant at higher nitrate concentrations by comparison to dissimilatory nitrate reduction, i.e. denitrification.  相似文献   

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