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Heavy Metal Content of Arable Soils in Northern Belgium
2003
De Temmerman, L. | Vanongeval, L. | Boon, W. | Hoenig, M. | Geypens, M.
More than 600 arable soils from Flanders (Northern-Belgium) were analysed for their total acid extractable contents of As, B, Be, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn in order to determine any increase in the natural background values. Samples were taken at random in several municipalities throughout Flanders. Areas with known historical or actual sources of trace element emissions were omitted although in some cases the distance between those sources and the sampling locations was not more than 20 km. The main soil types were, ranging from north to south: sand, loamy sand, light sandy-loam, sandy-loam and loam. In the coastal area, clay soils (sea polders) were sampled. In addition to the analysis of trace elements, the soil texture class, the pH and the carbon content were determined. Macro- or mesonutrients, Ca, K, P, Mg and Na, were determined from a weak acid extract of the soil samples. Correlations between trace elements and macronutrients provide some information about fertilisation practices and heavy metal sources.A limited number of soils showed slightly enhanced levels for As, Be, Cu, Co, Cr Mn, Ni Pb and Zn. In most cases, this could be linked to the regional industrial activities. However, a clear increase for Cu and Zn, above the natural background could be distinguished in areas with low atmospheric heavy metal deposits. In these cases, the excessive use of animal manure in the past may be the reason for this enrichment. However there was no indication that the Cd content of the soil was raised by the use of large amounts of pig slurry and/or by other common agricultural activities.
Mostrar más [+] Menos [-]An Application of Geographic Information System (GIS) to a Fictitous Thermal Power Plant in Mersin, Türkiye: An Application of Dispersion Modelling Coupled with GIS
2003
Oguz, Mustafa
In this study, local air quality impacts of a proposed conventionalcoal-fired power plant in the İçel region has been investigated using numerical dispersion modeling studies coupled with a GIS application. Within the impact area of the facility, Industrial Source Complex Short Term (ISCST2) dispersion model has been used to estimate ground-level concentrations of air pollutants originating from the power plant. For the same impact area, GIS applications have been utilised to determine the agricultural yield distribution. For this purpose, relevant satellite images were digitised, classified and statistically analyzed. Based on the predicted ground-level pollutant concentrations and sensitivity of the agricultural crops to the pollutants, agricultural yield loss was estimated for the impact area.The results have been quantified and valuated in monetary terms for the purpose of performing an environmental cost benefit analysis. Comparison of the conventional cost benefit analysis with the environmental cost benefit analysis showed the significance of the external cost of the proposed facility, resulting from the environmental damages.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]AgriBMPWater - system approach to environmentally acceptable farming : results in the perspective of potential users as farmers, land managers and water directors
2003
Turpin, N. | Laplana, R. | Strauss, P. | Kaljonen, M. | Barlund, I. | Benigni, G. | Bioteau, Thierry | Birgand, F. | Bontems, Philippe | Bordenave, Pierre | Eklo, O.M. | Feichtinger, F. | Garnier, M. | Haverkamp, R. | Leone, A. | PIET, Laurent | Romstad, E. | Rotillon, G. | Tattari, S. | Zahm, Frédéric | Lo Porto, Antonio | Lescot, Jean-Marie | Ripa, M.N.
A comparison between different existing or simulated BMPs has been carried out through a cost/effectiveness assessment along with the study of their acceptability by farmers on eight European watersheds in a multidisciplinary framework involving eleven research teams. Water quality problems encountered and dealt with in this project for all eight watersheds include: high nitrate loads and concentrations at the outlet of the two western French watersheds associated with dairy production, high loads of phosphorus into lake Vico (Italy) associated with hazelnut plantations, high nitrate concentration in groundwater for two watersheds in Austria and Italy, high sediment loads at the outlet of a second Austrian watershed, acid water associated with artificial drainage of moraine soils in Finland, pesticide contamination in Norway.The comparison of different BMPs for a given watershed is built as a 6 steps framework :step 1 : describing the watershed, the general problematic (including the objective of the different actors) and of the main water quality problems. .step 2 : describing and computing the hydrology. Description of the model used, calibration and validation of the model, definition of critical areas and risky practices, assessment of their impact on total fluxes or concentrations, deduction of proposed BMPs, assessment of the ex ante effectiveness of each BMP.step 3 : describing the economics. Description of the diversity of farms, choice of the model to represent this diversity, results of model implementation (does this model provide an acute description of the statu quo situation ?), assessment of the consequences on introducing BMPs and ex ante cost of this introduction.step 4 : assessing the results of steps 2 and 3 to a cost/efficiency ratio for each BMP.step 5 : interviewing the farmers to assess the acceptability for each BMP.step 6 : comparing of the cost/efficiency ratio and the acceptability to build a selection grid.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
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