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The Contribution to Nitrogen Deposition and Ozone Formation in South Norway from Atmospheric Emissions Related to the Petroleum Activity in the North Sea
2003
Solberg, S. | Lazaridis, M. | Walker, S.-E. | Knudsen, S. | Semb, A.
A photochemical puff-trajectory model (Fotoplume) has been applied to simulate emissions, atmospheric transport and chemical transformations of pollutants from offshore oil and gas production in the North Sea. The above model was used in conjunction with the European Monitoring and Evaluation Programme (EMEP) regional Lagrangian oxidant model. The Fotoplume and EMEP models were used to evaluate the effects of the atmospheric emissions from the oil and gas exploration activity in the Norwegian sector of the North Sea. Deposition of nitrogen and formation of boundary level ozone in Southern Norway due to North Sea emissions of nitrogen oxides (NOₓ), carbon monoxide (CO) and volatile organic compounds (VOC) have been studied. The petroleum activity in the North Sea is calculated to contribute approximately 20% of the nitrogen deposition in the coastal areas of Norway in 1992. In addition, the models were used to estimate the AOT40 ozone exposure levels. The results indicate that emissions from British and Norwegian oil and gas exploitation sector separately contribute to less than 5% each of the AOT40 values for coniferous forests and meadows. Comparison of model calculations with experimental measurements is quite satisfactory and the models show realistic results for both the nitrogen deposition and AOT40 values.
显示更多 [+] 显示较少 [-]Application of Bioassays for Risk Characterisation and Remediation Control of Soils Polluted with Nitroaromatics and PAHs
2003
Rila, Jean-Paul | Eisentraeger, Adolf
Six soil samples taken from three contaminated sites have been assessed using chemical, ecotoxicological and genotoxicological methods. From two of these sites, samples were characterised after remediation. An overall assessment of the soil samples was done with a scheme consisting of two phases. Remediation of main pollutants in these samples, did in general not lead to a risk reduction of the water-extractable ecotoxic and genotoxic potential. It was concluded, that the assessment and remediation of contaminated sites without consideration of biological test systems is not sufficient. Focussing on single hazardous compounds does in many cases not lead to a reduction of the ecotoxic or genotoxic potential. Consequently, effects of accompanying hazardous compounds, which are not routinely quantified, might be underestimated. It was pointed out, that the assessment of contaminated soil samples on the basis of LID-values applying dual dilution series seems to be sufficient for the evaluation, if there is no need for a quantitative comparison of toxic potentials.
显示更多 [+] 显示较少 [-]Magnetic Study of Weakly Contaminated Forest Soils
2003
Kapička, A. | Jordanova, N. | Petrovský, E. | Podrázský, V.
This paper reports on magnetic and magnetomineralogical studies of forest soils from Krkonoše (Giant Mountains) National Park in the Czech Republic. Low-field magnetic susceptibility was measured in 32 soil profiles using a field probe. Thermomagnetic analysis, acquisition of remanent magnetization, alternating-field demagnetization of saturation remanence and frequency-dependent magnetic susceptibility were measured in laboratory samples from individual soil horizons as well as on their magnetic extracts. X-ray diffraction and SEM were used to identify ferrimagnetic fractions. The uppermost layer, which is dominated by magnetically soft magnetite of presumably anthropogenic origin, can be reliably identified in soil profiles over the whole region of concern. Subsoil horizons are characterised by significantly different magnetic properties.
显示更多 [+] 显示较少 [-]Microbiological Properties in Acidic Forest Soils with Special Consideration of KCl Extractable Al
2003
Illmer, Paul | Obertegger, Ulrike | Schinner, Franz
To determine the importance of Al-availability for soil micro-organisms 95 forest soils from Tyrol/Austria with comparable topography, vegetation, climatic conditions, soil type and with low soil pH (median = 3.9) were investigated for their physical (percentage of stable aggregates, water holding capacity), chemical (pH, electrical conductivity, contents of organic matter, concentrations of easily extractable aluminium, calcium, potassium, magnesium and phosphorus) and microbiological characteristics (microbial biomass and respiration, metabolic quotient, content of ATP, activities of protease and CM-cellulase, cfu-values of total and Al-tolerant bacteria and fungi). A highly significant negative correlation was detected between concentrations of KCl-extractable aluminium and soil pH. By the application of multivariate statistical methods, the effect of the concentration of KCl-extractable aluminium on abundance and activities of soil micro-organisms could be revealed. Al turned out to be of great importance for micro-organisms and often outmatched the significance of other well known soil properties like organic matter, pH or water holding capacity. However, due to very healthy trees at the sites under investigation no effect of Al or soil acidification on forest decline could be detected.
显示更多 [+] 显示较少 [-]Adsorption, Desorption And Mobility of Fomesafen in Chinese Soils
2003
Guo, Jiangfeng | Zhu, Guonian | Shi, Jianjun | Sun, Jinhe
Fomesafen, 5-[2-chloro-4-(trifluoromethyl)phenoxy]-N-(methylsulfonyl)-2-nitrobenzamide, is used widely for weed control in soybeans since its introduction to China. Little information is available on its adsorption, desorption and movement in Chinese soils. The adsorption, desorption and mobility of fomesafen in six Chinese soils was studied. Adsorption isotherms agreed with the Freundlich equation very well. The results of regressionanalysis indicated that soil pH was more important than organic matter for fomesafen adsorption. Fomesafen was more readily desorbed from soils with 0.01 M CaSO₄solution. Soil TLC and column leaching studies showed that fomesafen and its metabolites was less mobile in Chinese soils. About 89.82% of applied fomesafen and its metabolites still remained in upper 5 cm layer 60 days after treatment under field conditions.
显示更多 [+] 显示较少 [-]Partitioning of Trace Metals in Suspended Sediments from Huanghe and Changjiang Rivers in Eastern China
2003
Peng, Shu-Heng | Wang, Wen-Xiong | Chen, Jingsheng
Assessing metal contamination of sediments requires knowledge of the geochemical partitioning of trace metals at the sediment-water interface. Under controlled laboratory conditions, sequential extraction was conducted to determine the associations of metals (Cd, Cr, and Zn) and radiotracers (¹⁰⁹Cd,⁵¹Cr, and⁶⁵Zn) with various geochemical phases and the different partitioning and mobility of metals for two types of surface sediments collected from the Huanghe and Changjiang Rivers in Eastern China. The residual phase was the major phase for stable metal binding, indicating that these sediments had little subjection to recent anthropogenic influences. Fe–Mn oxides were the next important binding phases for metals. The partitioning of metals in various geochemical phases as a function of the duration of the radiolabeling was also examined. Trace metals transferred among the different geochemical phases over the 30 days radiolabeling period, particularly between the carbonate and Fe–Mn oxides phases. The freshwater-sediment distribution coefficients (Kd) of three metals were investigated in batch experiments using the radiotracer technique. The decreasing Kdwith increasing metal concentration(from 0.5 to 200 μg L⁻¹) may be explained by competitive adsorption. The metal Kdin sediments from the Changjiang River was greater than those from the Huanghe River, presumably because of the higher Fe/Mn and organic carbon contents in Changjiang River sediment. The Kddecreased with increasing total suspended solid load from 3 to 500 mg L⁻¹, and was Cr > Zn > Cd. For Cd and Zn, increasing the pH from 5 to 8 resulted in an increase in Kddue to the reduced H⁺competition and increasing sorptionpotential. However, the Kdfor Cr in the sediments from both rivers showed no relationship with pH, presumably becauseof the complexity of the Cr species and environmental behavior.
显示更多 [+] 显示较少 [-]Pre-Treatment of Currency Printing Ink Wastewater through Coagulation-Flocculation Process
2003
Nandy, Tapas | Shastry, Sunita | Pathe, P. P. | Kaul, S. N.
Attempt has been made to study the treatability of printing ink wastewatergenerated from an Indian currency printing press using coagulation-flocculation process. Coagulant agents, viz. ferrous sulphate, ferric chloride, aluminium sulphate and polyaluminium chloride were studied to select the most suitablecoagulant for effective treatment, and attain the optimum coagulant concentration. Cationic polyeletrolyte in conjunction with the most effective coagulant was also studied to assess its effect on floc settleability. Polyaluminium chloride (PAC) was found to be the most efficient coagulant, achieving removals of colour, suspended solids (SS), biochemical oxygen demand (BOD) and chemical oxygen demand (COD) of 95.9–96.5%, 96.5–97.0%, 61.3–65.8%and 54.8–61.8%, respectively at an optimum concentration of 1500 mg L⁻¹. Other coagulants, viz. ferrous sulphate, ferric chloride and aluminium sulphate did not show substantial removals of colour, BOD and COD, except suspended solids in comparison to the performance of PAC. Cationic ploylectrolyte in combination with PAC at an optimum concentration of 1500 mg L⁻¹of PAC and 1.0 mg L⁻¹of polyelectrolyte further improved the removal efficiency of various parameters studied, in addition to improving the floc settling rate, and reduction in quantity of sludge generation.Effect of rapid mixing intensity expressed as mean temporal velocity gradient (G), and mixing time (t) on flocculation was also investigated. Rapid mixing at an impeller rotational speed (n) of 300 rpm and mixing time (t) of 60 sec indicated good floc formation, which resulted in achieving velocity gradient of 821 s⁻¹, and was found to be an optimum combination. This was also indicated by relatively high settling velocity of sludge formed and low residual colour in the supernatant. However, slow mixing beyond 5 min, adopted after initial optimum rapid mixing, indicated negligible effect on flocculation.
显示更多 [+] 显示较少 [-]Development of a Multi-Resolution Emission Inventory and Its Impact on Sulfur Distribution for Northeast Asia
2003
Woo, J.-H. | Baek, J. M. | Kim, J. W. | Carmichael, G. R. | Thongboonchoo, N. | Kim, S. T. | An, J. H.
Emissions in East Asia for 1993 by administrative units and source types are estimated to support regional emission assessments and transport modeling studies. Total emission of SOₓ, NOₓ, soil NOₓ, N₂O, and NH₃are 24 150, 12 610, 1963, 908, and 8263 kton yr⁻¹, respectively.China's emission contribution is the highest for every species.The area sources are the most significant source type for SOₓand NOₓ, but the fraction due to mobile source is highest for NOₓ. Major LPSs are located from the middle to the east part of China, south and middle-west part of South Korea, and the east part of Japan. The area sources of SOₓshow a pattern similar to population density, whereas NH₃shows a strong landuse dependency. Detail emissions analysis reveals higher SOₓemission `cores' within each province. The estimated emissions are used to estimate sulfur deposition in the regions. The seasonal average sulfur distribution amounts are estimated from the ATMOS2 chemical transport model. The results showed anti-correlation with temperature for sulfur (SO₂+ SO₄⁻²) concentrations and a positive correlation with rainfall for deposition.
显示更多 [+] 显示较少 [-]Estimation of Dust Emission Amount for a Dust Storm Event Occurred in April 1998 in China
2003
In, Hee-Jin | Park, Soon-Ung
The threshold friction velocities for dust rises in inland China are examined using WMO synoptic station data and the soil types in the source region to estimate dust emission amounts for a dust event occurred from 13 to 24 April 1998 in China. The dust-rise reports in the WMO synoptic data are used for the delineation of dust source regions that are found to be composed of the Gobi, Sand and Loess regions according to soil types in inland China. The estimated threshold friction velocities with the use of wind speeds observed in the Gobi, Sand and Loess regions are found to be about 60, 50, and 40 cm s⁻¹, respectively. The estimated dust-rise occurrencegrids by both the grid interpolated observed wind and the MM5 model wind well coincide with the areas of strong wind speeds. However, the dust-rise areas estimated by the model are larger than those estimated by the observed wind, whereas the friction velocities estimated by the model in the dust-rise areas are much smaller than those estimated by the observed wind, which result in less amount of dust emission by the model in all source regions. The 10-day accumulated total dust emission estimated by the observed wind during the dust storm event is found to be 4.64 × 10⁸ton in the whole source region of 3.29 × 10⁶km². Of which 85, 9 and 6% are, respectively, contributed by the Gobi, Sand and Loess regions,suggesting the dominant emission from the Gobi region for this event.The model estimated total dust emission is found to be about 56% of that estimated by the observed wind, indicating some improvement of the model being required.
显示更多 [+] 显示较少 [-]Concentrations of Mercury in Wild Growing Higher Fungi and underlying Substrate near Lake Wdzydze, Poland
2003
Falandysz, J. | Brzostowski, A. | Kawano, M. | Kannan, K. | Puzyn, T. | Lipka, K.
Fourteen species of wild growing mushrooms and surface (0–10 cm) soils were collected near Lake Wdzydze in the northern part of Poland in 1996–1997 to understand the status of mercury pollution. Concentrations of mercury in mushrooms varied between 100±30 and 2400±1900 ng g⁻¹dry matter in caps and 60±1 and 1300±1500 ng g⁻¹dry matter in stalks. Concentrations of mercury in underlying soil were between 30±1 and 140±120 ng g⁻¹dry matter (between 36±18 and 63±100 ng g⁻¹depending on the soil type). Bioconcentration factors (BCF: concentrations in mushroom/concentrationin soil) of total mercury were between 2.3±1.1 and 90±110 for caps, and between 2.1±1.0 and 53±56 for stalks. Scaly tooth (Sarcodon imbricatum) contained the greatest concentrations of mercury in the flesh. However, there was no significant relationship (p >: 0.05) between mercury content in the fruiting bodies of this speciesto soil mercury concentrations. A significant (p < 0.01) positive relationship between mercury content in caps to underlying soil was noted for European cow bolete (Suillus bovinus), while a negative relationship between mercury content in caps and stalks to underlying soil was observed for Sandy knight-cap (Tricholomaflavovirens), Shaggy scale-head (Pholiota squaroso-adiposa),Gypsy mushroom (Rozites caperata) and Pine spike cap (Chroogomphus rutilus).
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