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Contamination of beech and oak by pollutants in area of magnesite plant
2002
Mankovska, B. | Tucekova, A. (Forest Research Institute, Zvolen (Slovak Republic)) | Novak, J.
The magnesite plants Jelsava and Lubenik emitted in the 80s 30 000 tons of magnesite dust and heavy metals and 4000 tons of SO2 per year, what caused an extreme damage to the vegetation in the area around of about 500 km2. For the determination of 3 zones of endangerment we used pollution index values. In each pollution zone we demarcated experimental plots and carried out soil analyses. Forest stands polluted by magnesite dust belong to alkaline air pollution type
Afficher plus [+] Moins [-]Influence of 2,4-D and MCPA herbicides on uptake and translocation of heavy metals in wheat (Triticum aestivum L.) Texte intégral
2017
Skiba, Elżbieta | Kobyłecka, Joanna | Wolf, Wojciech M.
The aim of the study was to estimate the influence of the 2,4-dichlorophenoxy acetic acid and 2-methyl-4-chlorophenoxyacetic acid on the uptake and translocation of Cd, Co, Ni, Cu, Zn, Pb and Mn by wheat (Triticum aestivum L.). Two farmland soils typical for the central Polish rural environment were used. Studies involved soil analyses, contents of bioavailable, exchangeable and total forms for all investigated metals. Atomic absorption spectrometry was used to determine the concentration of the elements. The best correlation between the herbicide rate and the metal concentration was visibly for the underground part of plants. Analysis of variance proved that herbicide treatment of wheat frequently influences the metal transfer from soil and their concentration in roots and shoots. In particular, higher herbicide rates prompted the significant increase of all metals concentration in roots. Additionally, transfer coefficients depended on the type of soil and the herbicide rate applied. Uptake of metals may be also influenced by the formation of sparingly water-soluble metal-herbicide complexes. Its intensity would then depend on the solubility of particular chemical entity with the low solvable Pb, Cu and Cd complexes being the least mobile.
Afficher plus [+] Moins [-]Synthetic fertilizer management for China’s cereal crops has reduced N₂O emissions since the early 2000s Texte intégral
2012
Sun, Wenjuan | Huang, Yao
China has implemented a soil testing and fertilizer recommendation (STFR) program to reduce the over-usage of synthetic nitrogen (N) fertilizer on cereal crops since the late 1990s. Using province scale datasets, we estimated an annual reduction rate of 2.5–5.1 kg N ha⁻¹ from 1998 to 2008 and improving grain yields, which were attributed to the balanced application of phosphate and potassium fertilization. Relative to the means for 1998–2000, the synthetic N fertilizer input and the corresponding N-induced N₂O production in cereal crops were reduced by 22 ± 0.7 Tg N and 241 ± 4 Gg N₂O–N in 2001–2008. Further investigation suggested that the N₂O emission related to wheat and maize cultivation could be reduced by 32–43 Gg N₂O–N per year in China (26%–41% of the emissions in 2008) if the STFR practice is implemented universally in the future.
Afficher plus [+] Moins [-]Short- and long-term temporal changes in soil concentrations of selected endocrine disrupting compounds (EDCs) following single or multiple applications of sewage sludge to pastures Texte intégral
2013
Rhind, S.M. | Kyle, C.E. | Ruffie, H. | Calmettes, E. | Osprey, M. | Zhang, Z.L. | Hamilton, D. | McKenzie, C.
Temporal changes in soil burdens of selected endocrine disrupting compounds were determined following application to pasture of either sewage sludge or inorganic fertilizer. Soil polycyclic aromatic hydrocarbon and polychlorinated biphenyl concentrations were not altered. Changes in concentrations of diethylhexyl phthalate (DEHP) and PBDEs 47 and 99 differed with season but concentrations remained elevated for more than three weeks after application, when grazing animals are normally excluded from pasture. It is concluded that single applications of sewage sludge can increase soil concentrations of some, but not all classes of EDCs, possibly to concentrations sufficient to exert biological effects when different chemicals act in combination, but patterns of change depend on season and soil temperature. Analysis of soil from pasture subjected to repeated sludge applications, over 13 years, provided preliminary evidence of greater increases in soil burdens of all of the EDC groups measured, including all of the PBDE congeners measured.
Afficher plus [+] Moins [-]The source of lead determines the relationship between soil properties and lead bioaccessibility Texte intégral
2019
Yan, Kaihong | Dong, Zhaomin | Wijayawardena, MA Ayanka | Liu, Yanju | Li, Yubiao | Naidu, R.
Lead (Pb) contaminated soil is of particular concern for infants and children due to their susceptibility to exposure, fast metabolic rates and rapidly developing neuronal systems. Determining the bioaccessibility of Pb in soils is critical in human health risk assessments, which can vary due to different soil properties and sources of Pb contamination. In this study, the potential relationships between soil properties and Pb bioaccessibility from various Pb sources including Pb contamination from mining (specifically, Broken Hill), three shooting ranges, a smelter and two industry sites (pottery and battery), were investigated using the Relative Bioavailability Leaching Procedure (RBALP). We found the following: (1) CEC, TOC, sand and silt content, and total Pb were significantly different (p < 0.05) between the two particle size fractions of < 2 mm and < 250 μm; (2) EC, CEC and total Pb were significantly correlated to Pb bioaccessibility (p < 0.05); and (3) soil analyses based on source of Pb demonstrated a strongly significant relationship between Pb bioaccessibility and soil properties (CEC, EC, clay content and total Pb) for mining soils from Broken Hill (r² = 0.86, p < 0.05, n = 18). These results demonstrated the influences of Pb contamination sources, soil properties and particle size fractions on Pb bioaccessibility as well as the prediction of Pb bioaccessibility using soil properties. The findings documented here will help in developing a predictive tool for human health risk assessment and the remediation of Pb contaminated soils.
Afficher plus [+] Moins [-]A study of the influence of sewage sludge fertilization on the concentrations of PCDD/F and PCB in soil and milk
1994
McLachlan, M.S. | Hinkel, M. | Reissinger, M. | Hippelein, M. | Kaupp, H. (Ecological Chemistry, University of Bayreuth, 95440 Bayreuth (Germany))
SEM-EDAX analysis of the Soil Samples of River Yamuna in Delhi Texte intégral
2021
Vivek Chopra and Jai Gopal Sharma
A total of 18 samples were collected from two different sites at different depths of Yamuna river bed in Delhi. Nine samples were collected at Site A (Palla Village) from three different locations at different depths of the river bed. A similar set of 9 samples were collected from Site B (Okhla barrage). All samples were analysed for atomic and weight percentage of elements using SEM-EDAX. The major elements found in the study were Si, O, Al and Nb. Si and O are found in a maximum amount in all the samples with a varying range of atomic percentage 25.3-89.27 and 55.09-95.78 respectively. The recorded atomic percentage of Nb was 0.32 while Al was 16.7-25.51. Site A, Palla is least affected by pollution while at Site B the presence of Al revealed contamination from pollutants. The weight percentage of the elements has also been calculated. SEM images of soil samples revealed the platy flakes, irregular and spongy structure of soil particles.
Afficher plus [+] Moins [-]Gold Mine Impact on Soil Quality, Youga, Southern Burkina Faso, West Africa Texte intégral
2019
Compaore, Wendkuuni Florentin | Dumoulin, Ann | Rousseau, Diederik P. L.
The present study aims to assess the impact of a gold mine located in the southeastern part of Burkina Faso on local soil quality. This information is needed in order to determine any health hazards and potential remediation strategies as the mining site is expected to be turned over to the local community after the closure of the mine. For the purpose, total minor and trace elements analysis as well as a sequential extraction were performed and results were interpreted using different methodologies: enrichment factor (EF), geoaccumulation index (Igeo) computed using two separate background samples, and comparison to selected national standard. The soil analysis revealed a moderate to significant soil EF and Igeo with hotspots located closer to the ore processing plant and on the east side of the site, with a maximum arsenic concentration of 286.55 ± 12.50 mg/kg. Sequential extraction revealed, however, that less than 2% of the arsenic is found in the exchangeable part. Cobalt and zinc are more distributed in the different fractions than arsenic. Geogenic and anthropogenic contributions were revealed by the study. Graphical Abstract .
Afficher plus [+] Moins [-]Characterization and Treatment of Sulfochromic Residues Generated from Soil Analysis Texte intégral
2016
Kist, Lourdes Teresinha | Bakalian, Ana Márcia Crovetto | Machado, Ênio Leandro | Moro, Celso Camilo
Research and routine analysis laboratories produce sizeable amounts of residues as a result of experiments and by-products of chemical reactions. An example of that is soil analysis, in which a sulfochromic solution is used for the determination of organic matter content. This solution contains sodium dichromate and sulfuric acid, reagents that oxidize the soil’s organic fractions and contribute to the presence of chromium in laboratory residues discharged into the environment. In an attempt to find solutions to environmental problems, the aim of the present study was to quantitatively and qualitatively characterize chromium-contaminated residues generated during soil analysis. Therefore, management methods were proposed in order to recover chromium in its trivalent form (Cr³⁺) by precipitation. The use of biochemical oxygen demand, chemical oxygen demand, nitrogen, phosphorus, and metals to characterize the samples revealed the presence of 16.76 g L⁻¹ of total chromium, with 4.19 g L⁻¹ of Cr(VI). By means of ozonation, 68 % of the chromium was converted to liquid form and, after being reduced with bisulfite, it was turned into chromium sulfate (III). The remainder, 32 %, was kept with the other metals present in the solid form (sludge).
Afficher plus [+] Moins [-]Enhanced Electrokinetic Transport of Sulfate in Saline Soil Texte intégral
2015
Jo, SungUng | Shin, Yeon-Jun | Yang, Jung-Seok | Moon, Deok Hyun | Koutsospyros, Agamemnon | Baek, Kitae
The electrokinetic transport of sulfate was investigated as a means of treating and restoring a sulfate-accumulating saline soil. The electrokinetic treatment decreased the electrical conductivity of the soil, an indicator of soil salinity, to 58.6, 73.1, and 83.5 % for 7, 14, and 21 days, respectively. More than 96 % of the chloride and nitrate were removed within 7 days. However, the removal of sulfate was highly influenced by the anode material. An iron anode removed sulfate effectively, whereas sulfate was hyper-accumulated in the anodic region when an inert anode was used. The iron anode was oxidized in a sacrificial anodic reaction, which competed with the electrolysis reaction of water at the anode, and finally, the reaction prevented the severe acidification of the soil in the anodic region. However, the competing reactions produced hydrogen ions at the anode and the ions were transported toward the cathode, which, in turn, acidified the soil, especially in the anodic region. The acidification switched the surface charge of the soil from negative to positive, increasing the interaction between the soil surface and sulfate and thus inhibiting the transport of sulfate under the electric field. The zeta potential analysis of the soil provided an explanation. The results indicate that preventing severe acidification is an important factor which influences the transport of anions and iron anode for the enhanced removal of anionic pollutants by electrokinetic remediation.
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