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1.
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   

2.
Total S concentrations in Scots pine (Pine sylvestris L.) needles and the lichen Hypogymnia physodes collected from the vicinity of an oil refinery in southern Finland and a steel works in northern Finland were used as a bioindicator for SO2 deposition. The mean total S concentration in the youngest pine needles decreased by 22% (p <0.001) and that of the second youngest needles by 28% (p < 0.001) as emissions from the oil refinery were reduced by nearly 50% from 1980 to 1985. Total S concentration in both needles and lichens were higher in the vicinity of the oil refinery due to the greater influence of long-range transport S deposition in southern Finland. The two industrial plants had approximately equal SO2 emissions in 1985. The results suggest that the total S concentration in pine needles is a better indicator of SO2 changes in the ambient air, while that in Hypogymnia physodes seems to be a better bioindicator of total S deposition, past and present.  相似文献   

3.
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   

4.
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   

5.
Abstract

Current nitrogen (N) fertilizer recommendations for Kentucky bluegrass (Poa pratensis L.) seed production in northern Idaho are based on potential yield and annual precipitation. Soil test correlation information collected for other northern Idaho crops provide the basis for P, S and B recommendations. The objective of this paper is to assess the current recommendations with a series of forty field trials conducted on ten sites during four seed production seasons. All field trials were conducted on Alfisols and Mollisols initially containing less than 60 kg N/ha, 3.5 μg/g NaOAc extractable P, 40 kg extractable SO4‐S/ha and 0.5 μg/g extractable B. Fertilization rates evaluated included: 0, 50, 75, 100, 125, 150 and 200 kg N/ha; 0, 30 and 60 kg P2O5/ha; 0, 25, and 50 kg SO4‐S/ha, and 0 and 1.5 kg B/ha. Five field sites contained the cultivar ‘Argyle’ Kentucky bluegrass seed, while the other five sites contained the cultivar ‘South Dakota’.

Excellent relationships between percent maximum Kentucky bluegrass seed production and the sum of inorganic soil N + fertilizer N applied were observed for the ‘Argyle’ (R2=0.65) and ‘South Dakota’ (R2=0.72) cultivars. Phosphorus applications of 30 kg P2O5/ha improved seed yields from 10.0 to 51.6% when initial soil test values were less than 3.0 6 μg/g NaOAc extractable P. When initial SO4‐S soil values were less than 32 kg/ha fertilizer additions increased seed yields from 12.6 to 107.3%. Boron applications did not improve seed yields. Analysis of these trials indicates that adequate information is available to make satisfactory P, S and B fertilizer recommendations; however, additional soil test correlation information is needed for N recommendations.  相似文献   

6.
Generally, dry deposition processes are very important for atmospheric chemistry of pollutants providing up to 30–80 % of the removal for certain compounds from the atmosphere. The model for calculating of dry deposition fluxes for a large territory seems unsophisticated in spite of the dependence on surface characteristics, pollutant properties and atmospheric conditions. The approach of combining monthly average concentrations measured at the Integrated Background Monitoring Network (IBMoN) and EMEP stations and linear dry deposition velocity was used to calculate total sulphur and nitrogen fluxes for the whole of the former Soviet Union (FSU) taking into account large-scale geographical variability in climate and lands. Most values of all SO2 and SO4 2? concentrations were below 2.9 and 3.1 mgS/m3, and NO2 concentration were 1.5 mgN/m3 over European part and 0.6 mgN/m3 in Western Siberia. The long-term trends of oxidised sulphur and nitrogen compounds in the atmosphere were examined for 1982–1998 in certain FSU regions. Annual dry deposition of sulphur was estimated as 3.64 Mt S (in sulphate form) and 2.76 Mt S (in SO2 form) for the whole area of FSU. Annual removal of NO2 by dry deposition was calculated at 1.27 Mt N. These values constituted between 44 and 50% of total oxidised sulphur and nitrogen deposition.  相似文献   

7.
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   

8.
Total S content of the humus layer was determined from Scots pine forests in the surroundings of Oulu, an industrialized city in northern Finland. The S content nearest the city center and emission sources (zone IV; bar x=3870 μg g?1 on an organic matter basis) was about twice as high as in three background areas (80 to 170 km from the city) and about 40% higher than at the sites which were ca 20 km from the main emission sources (zone I). The estimated accumulation of S in humus layer was, on average, 0.4 to 0.6 g m?2 yr?1 in the most polluted study sites and 0.1 to 0.2, 0.2 to 0.3 and 0.4 to 0.5 g m?2 yr?1 in zones I, II, and III, respectively.  相似文献   

9.
Information on the influence of soil moisture on elemental sulphur (S0) oxidation and transformation into organic S in semi-arid subtropical soils is scarce. We studied the impact of three moisture regimes on the mineralization of soil organic S, and the oxidation and immobilization of S0 in acidic (pH 4.9), neutral (pH 7.1) and alkaline (pH 10.2) subtropical soils. Repacked soil cores were incubated under aerobic (40% and 60% water-filled pore space, WFPS) and flooded soil conditions (120% WFPS) for 0, 14, 28 and 42 days with and without incorporated S0 (500 µg g-1 soil). Soil moisture had profound effects on these processes and the mineralization of native soil organic S, oxidation of applied S0 and transformation of S0 into soil organic S proceeded most rapidly at 60% WFPS, irrespective of soil pH. Mineralization of native soil organic S resulted in the accumulation of 34, 49 and 44 g SO42--S g-1 soil in acidic, neutral and alkaline soil in a 42-day period at 60% WFPS. The oxidation rate of added S0 during the initial 14-day period at 60% WFPS was highest in alkaline soil (428 µg S cm-2 day-1), followed by neutral soil (326 µg S cm-2 day-1), and lowest in acidic soil (235 µg S cm-2 day-1). These rates are several folds higher than those reported in earlier studies because now we computed the oxidation rates by including the amount of S0 that was immobilized to organic S. Of the applied S0 at 40% and 60% WFPS, 2.6% and 6.0%, 3.4% and 10.0%, and 9.4% and 14.4% oxidized to SO42-, and 15.0% and 17.6%, 17.6% and 19.6%, and 17.6% and 23.6% transformed into organic S in the 42-day period in acidic, neutral and alkaline soil, respectively. These results suggest that in order to synchronize the availability of S with plant need, S0 may be applied well before the seeding of crops especially in acidic soils and in rainfed regions where soil moisture remains at less than 60% WFPS. Apparently no oxidation of S0 and significant reduction of SO42--S (7, 53 and 78 µg SO42--S g-1 in acidic, neutral and alkaline soil, respectively) under flooded conditions suggest that S0 is least effective for correcting S deficiency in flooded soil systems such as rice fields.  相似文献   

10.
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   

11.
Changes in fertilizer and pesticide formulations plus success in reducing sulfur (S) emissions to the air from industrial operations have reduced the availability of S to peach trees in some locations. Peach (Prunus persica L. Batsch) trees on highly leached acid sands have shown responses to S fertilization. The levels of total S required for S sufficiency is important to determine fertilizer needs. The 100 ppm SO4‐S requirement offered by some sources has been misinterpreted. Greenhouse experiments with Nemaguard, Lovell, Montclar and Nemared rootstock seedlings resulted in the establishment of levels representing S deficiency and sufficiency. The foliage and growth rates of rootstock seedlings in this experiment showed severe deficiency symptoms at 550–990 μg S g‐1 DW. Sufficiency was achieved at 1400–2500 μg S g‐1 DW.  相似文献   

12.
Abstract

A study of sulphur movement through a Scots pine forest involved the analysis of S and 35S in rainfall, throughfall and stem flow solutions, and aqueous extracts of needles and soil, together with measurement of total levels in soil and needles. Solution preparation procedures were developed so that the solutions could be used for liquid scintillation counting, ion chromatography and ICP/OES instrumental methods, ie., it was possible to analyse stable and radioactive sulphur fractions on the same sample solutions. Counting efficiency of the beta radiation from 35S in the study solutions ranged from 10 to 80%, with the greatest quenching occurring in soil nitric acid digestion solutions. A single non‐linear mathematical relationship was applied to correct the beta counts for energy quenching in all solutions with minimal bias when compared to the values derived from using separate factors for each solution type.  相似文献   

13.
Litter bags were used to determine the effects of SO2 and substrate-S content on decomposition rates of western wheatgrass tillers in the field. Atmospheric SO2 decreased monthly decomposition rates 32 to 44% in spring and early summer and 12% in dry late summer. Increased S content of the substrate (980 μg g?1 vs 590 μg g?1 in control) had no measurable effect on decomposition. The observed inhibition was probably caused by reduced pH and/or accumulation of toxic derivatives of SO2 in the microenvironment of organisms on the decaying leaf surfaces.  相似文献   

14.
Microbial biomass C and soil respiration measurements were made in 17–20 yr old soils developed on sluiced and tipped coal‐combustion ashes. Topsoil (0–30 cm) and subsoil (30–100 cm) samples were collected from three soil profiles at two abandoned disposal sites located in the city area of Halle, Saxony‐Anhalt. Selected soil physical (bulk density and texture) and chemical (pH, organic C, total N, CEC, plant available K and P, and total Cd and Cu) properties were measured. pH values were significantly lower while organic C and total N contents and the C : N ratio were significantly higher in the topsoil than in the subsoil indicating the effects of substrate weathering and pedogenic C accumulation. Likewise, microbial biomass C, K2SO4‐extractable C, and soil respiration with median values of 786 μg biomass C g–1, 262 μg K2SO4‐C g–1, and 6.05 μg CO2‐C g–1 h–1, respectively, were significantly higher in the topsoil than in the subsoil. However, no significant difference was observed in metabolic quotient between the topsoil and the subsoil. Metabolic quotient with median values of 5.98 and 8.54 mg CO2‐C (g biomass C)–1 h–1 for the 0–30 cm and 30–100 cm depths, respectively, was higher than the data reported in the literature for arable and forest soils. Microbial biomass C correlated significantly with extractable C but no relationship was observed between it and total N, Cd, and Cu contents, as well as plant‐available K and P. We conclude that the presence of the remarkable concentration of extractable C in the weathered lignite ashes allowed the establishment of microbial populations with high biomass. The high metabolic quotients observed might be attributed to the heavy‐metal contamination and to the microbial communities specific to ash soils.  相似文献   

15.
《Journal of plant nutrition》2013,36(10):2151-2159
ABSTRACT

The impact that nitrogen (N), phosphorus (P), and potassium (K) application rates on the sulfur (S) fractions in leaves and fruits of greenhouse-grown cucumbers plants (Cucumis sativus L. cv. Brunex) are presented. The treatments were as follows: N (N1=5 g NO3NH4/m2, N2=10 g NO3NH4/m2, N3=20 g NO3NH4/m2, N4=40 g NO3NH4/m2), two levels of P (P1=8 g H3PO4/m2 and P2=16 g H3PO4/m2), and two levels of K (K1=20 g K2SO4/m2 and K2=40 g K2SO4/m2). The foliar and fruit contents were determined for total S, organic S and sulfate. The influence of the N treatments on the total S (St: organic S +sulfate) concentration, proved significant, showing a progressive increase in the leaf and fruit concentrations. In the leaves, the P slightly diminished the St concentration but values in the fruits did not appreciably differ from control. The K dosage did not cause the St concentration to differ from that of P, although in the fruit a slightly lower St concentration appeared in the K2 treatment. The response of the organic-S concentration in the leaves resembled that of St, and thus organic S should not be used as a diagnostic method for S status. In the relationship SO4 2-/St, the SO4 2- concentration proved more influential than did the St form, providing a more accurate representation of the potential status of this nutrient in the plant.  相似文献   

16.
The cryptogamic soil crusts of the Great Basin Artemisia, Ceratoides, and Atriplex plant communities contain a significant heterotrophic N2-fixing microbial population in addition to the predominating filamentous cyanobacteria. The bacterial association with the cyanobacteria exhibits a phycosphere-like effect. Heterotrophically fixed N gains reached 17.5 μg N· g?1 of soil (23.1% increase above the initial soil N content) and 45.9 μg N·g?1 of soil (57.4% increase) after 3 and 5 weeks, respectively. (NH4)2SO4 and native plant material amendments to soil resulted in a 41–100% reduction in N2-fixation. The potential input of N to soil crusts may be reduced in the presence of shrub-produced allelochemic agents and by concurrent denitrification.  相似文献   

17.
Immobilization of N was measured in a fumigated and in an unfumigated soil by adding (15NH4)2SO4 and following the disappearance of inorganic label from the soil solution and its simultaneous conversion to soil organic N. Calculations based on the measurement of organically-bound 15N gave more consistent values for immobilization than did calculations based on the measurement of the disappearance of label from solution. The fumigated soil immobilized 6.6 μg N g?1 N g?1 soil in 10 days at 25°C, the unfumigated control 4.8 μg. The corresponding gross mineralization rates were 34.9 and 5.6 μg N g?1 soil in 10 days.Addition of 58 μg N as (15NH4)2SO4 to the fumigated soil increased the quantity of the ynlabelled NH4-N extracted at the end of 10 days from 33.8 to 37.8 μg Ng?1 soil, i.e. there was a positive Added Nitrogen Interaction (ANI). The added labelled N produced this ANI, not by increasing the rate of mineralization of organic N, but by standing proxy for unlabelled N that otherwise would have been immobilized.A procedure for calculating biomass N from the size of the flush of mineral N caused by fumigation is proposed. Biomass N (BN) is calculated from the relationship BN = F'N/0.68 where F'N is [(N in fumigated soil incubated for 10 days — (N in unfumigated soil incubated for 10 days)].  相似文献   

18.
Short-term competition between soil microbes and seedlings of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies (L.) Karst.) and silver birch (Betula pendula Roth) for N was assessed in a pot study using (15NH4)2SO4 as a tracer. Seedlings were grown in organic and mineral soil, collected from a podsol soil; 3.18 mg (15NH4)2SO4 per pot were injected into the soil, corresponding to 4 µg 15N g-1 d.m. (dry matter) mineral soil and 17 µg 15N g-1 d.m. organic soil. The amounts of N and 15N in the seedlings and in microbial biomass derived from fumigation-extraction were measured 48 h after addition of 15N. In the mineral soil, 19–30% of the added 15N was found in the plants and 14–20% in the microbial biomass. There were no statistically significant differences between the tree species. In the organic soil, 74% of the added 15N was recovered in the microbial biomass in birch soil, compared to 26% and 17% in pine and spruce soils, respectively. Correspondingly, about 70% of the 15N was recovered in pine and spruce seedlings, and only 23% in birch seedlings. In conclusion, plants generally competed more successfully for added 15NH4 + than soil microbes did. An exception was birch growing in organic soil, where the greater amount of available C from birch root exudates perhaps enabled micro-organisms to utilise more N.  相似文献   

19.
Abstract

A greenhouse experiment was conducted at the University of lbadan, Nigeria to determine the optimum sulphur (S) rate for Celosia (Celosia argentia L. CV. TLV 8) production under hydroponic growing conditions. Average temperature and light intensity in the greenhouse was 27.7°C and 1.32 x 103 μEinstein M‐2 S‐1 (PAR), respectively. Five rates of S(0, 13.5, 27, 40.5, and 54 ug g?1 of sand) in a series of nutrient solutions were imposed in a completely randomized design. Application of S significantly increased leaf number, plant height, leaf area, weights of leaf, stem, root, and raised contents of leaf sulphate (SO4)‐S, chlorophyll, vitamins A and C, and crude protein. The optimum S rate for leaf formation, plant height at harvest (seven weeks after transplanting‐WAT), shoot production, SO4‐S, vitamin A, and crude protein synthesis was 40.5 μg S g?1 of sand in the applied nutrient solution, while that for maximum leaf production, chlorophyll, and vitamin C synthesis was 54 ug S g?1 of sand. These results indicate that S nutrition is necessary for the optimum growth, yield, and yield attributes of Celosia.  相似文献   

20.
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   

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