scholarly journals Measurement of Soluble Arsenic in Soil of Bangladesh by Acid-alkali Sequential Extraction

2008 ◽  
Vol 1 (1) ◽  
pp. 92-107 ◽  
Author(s):  
Mohammad Shafiul Azam ◽  
Md. Shafiquzzaman ◽  
Iori Mishima ◽  
Jun Nakajima
Keyword(s):  
Sequential Extraction ◽  
Soil Phosphorus ◽  
Extraction Procedure ◽  
Soil Surface ◽  
Soil Samples ◽  
Wet Season ◽  
Arsenic Mobility ◽  
Reducing Conditions ◽  
Sequential Extraction Method ◽  
Core Soil

To measure easily soluble fraction of arsenic, a sequential extraction method by 0.1N HCl and 0.1N NaOH was used according to the soil phosphorus extraction procedure. The effects of reducing conditions on arsenic extraction were examined in incubation test. In high reducing conditions arsenic solubility was shown to be high and seemed to be controlled by dissolution of iron oxy-hydroxides. pH played a predominant role in determining the concentrations of soluble arsenic. Arsenic solubility could be possible at low or high pH conditions. Released arsenic in different pH and redox conditions showed that it is a part of acid extractable arsenic which is sorbed weakly on the soil surface and can be extracted during acid-alkali sequential extraction. Therefore, the method could be applicable to measure potential solubility of arsenic as a result of alteration in soil (e.g. redox, pH) and environmental factors. Sequential extraction results of the soil samples collected in dry and wet season suggested that acid-alkali extracted arsenic fractions of surface and core soil samples of paddy field were increased in wet season. They seemed to be moved with irrigation groundwater. Keywords: Acid-alkali extraction; Arsenic contamination; Soil arsenic mobility; Groundwater contamination; Paddy soil.  © 2009 JSR Publications. ISSN: 2070-0237(Print); 2070-0245 (Online). All rights reserved. DOI: 10.3329/jsr.v1i1.1058  

scholarly journals Application of a Sequential Extraction Method for Analyzing Cu Distribution in Pre-Treated Mine Tailings after Electrodialytic Remediation

2019 ◽  
Vol 16 (4) ◽  
pp. 584 ◽  
Author(s):  
Andrea Lazo ◽  
Henrik Hansen ◽  
Pamela Lazo ◽  
Claudia Gutiérrez
Keyword(s):  
Sequential Extraction ◽  
Mine Tailings ◽  
Extraction Method ◽  
Constant Electric Field ◽  
Extraction Procedure ◽  
Water Soluble ◽  
Copper Compounds ◽  
Leaching Solution ◽  
Sequential Extraction Method ◽  
Pre Treatment

Mine tailings have been analyzed by a sequential extraction procedure after their pre-treatment with a leaching solution for 24 h and electrodialytic remediation during 15 days with a constant electric field of 2.7 V cm−1. Four leaching solutions were tested: H2SO4 + HNO3 (2:1 vol.) pH = 1.9; H2SO4 + HNO3 (2:1 vol) pH = 4.2; NH4Cl 0.8M, pH = 5.5 and 30% H2O2 adjusted to pH 2 with HNO3 1M + HCl 1M. After the treatment, the tailings were divided in six slices from anode to cathode. The highest removal efficiency of copper was obtained with H2SO4 + HNO3 pH = 1.9, which allows one to remove 67% of the copper in the total cell and 85% of the copper in the slice closest to anode. The same solution with pH = 4.2 allows one to remove 62% of the total copper. The analysis realized by the sequential extraction method indicates the easy removal of water-soluble and exchangeable fractions in all experiments, moreover, residual and sulfide are the less mobile fractions. The general trend was the movement of copper associated to different fractions from anode to cathode and its accumulation closest to the cathode in the case of exchangeable, Fe-Mn oxides and acid soluble fractions, possibly due to some precipitation of copper compounds associated with less acidic conditions.

scholarly journals Soil compaction by the tractor in spring and its effect on soil porosity 

1983 ◽  
Vol 55 (2) ◽  
pp. 91-107
Author(s):  
Erkki Aura
Keyword(s):  
Soil Compaction ◽  
Theoretical Calculations ◽  
Soil Surface ◽  
Mechanical Impedance ◽  
Soil Samples ◽  
Soil Porosity ◽  
Sowing Time ◽  
Compacted Soil ◽  
Core Soil ◽  
Porosity Measurements

The effect on soil porosity of tractor compaction of soil in the spring was studied by taking cylindrical core soil samples. The profile samples showed that the tractor most seriously compacts the soil below the harrowed layer at the depth of 10-25 cm. Soil was compacted most severely when till age and drilling were performed under wet conditions about one week be for enormal sowing time. The sub soil at the depth of 35-40 cm was compacted only under very wet conditions. The grain yield of wheat was significantly reduced when the volume of large pores was reduced to about 10 % or less. Porosity measurements showed that the severely compacted soil almost completely recovered from one spring to the next. Theoretical calculations suggested that compaction by normal traffic does not cause a shortage of oxygen at least in the inter-crumb pores of soil if the soil surface structure is not dispersed and encrusted. The decrease in crop growth by compaction is primarily due to mechanical impedance, which slows down development of the root system.

scholarly journals Fractionation of soil phosphorus in a long-term phosphate fertilization

2012 ◽  
Vol 77 (7) ◽  
pp. 971-981 ◽  
Author(s):  
Nasser Amaizah ◽  
Dragan Cakmak ◽  
Elmira Saljnikov ◽  
Goran Roglic ◽  
Vesna Mrvic ◽  
...  
Keyword(s):  
Sequential Extraction ◽  
Organic Phosphorus ◽  
Soil Phosphorus ◽  
Extraction Procedure ◽  
Phosphate Fertilizer ◽  
P Fractions ◽  
Phosphorus Species ◽  
Comparison Of The Results ◽  
Phosphorus Application

The changes in inorganic and organic phosphorus (P) fractions of soil resulting from long-term fertilization (40 years) were investigated. In order to improve understanding of the sink and sources of phosphorus, P-fractions were extracted from soil samples of 0-30 and 30-60 cm depth with different amounts of monoammonium-phosphate (MAP) and then determined. Stagnosol was the type of the studied soil. Phosphate fertilizer was applied in 26, 39 and 52 kgP/ha amounts during the period of 40 years. Samples were subjected to sequential extraction according to the modified Chang and Jackson method and BCR (Community Bureau of Reference) sequential extraction procedure in order to extract different forms of phosphorus. The Certified Reference material CRM 684 (River Sediment Extractable Phosphorus) was used to provide accuracy of the instrument and both used methods. Furthermore, the association of phosphorus with substrates was provided by comparison of the results of sequential methods of phosphorus species with the sequential extraction of metals (Fe, Al, Mn and Ca). Results of continuous fertilization during 40 years indicated the increase of all the phosphorus forms in the soil except of phosphorus bound to calcium and organic phosphorus. Application of higher amounts of P-fertilizer resulted in dominance of Al-P fraction in studied soil which indicated that this fraction was the most responsible for the migration of phosphorus along the soil profile.

Sequential Extraction of Vanadium in Different Soil Samples Using Conventional and Ultrasonic Devices

2013 ◽  
Vol 96 (3) ◽  
pp. 650-656 ◽  
Author(s):  
Sumaira Khan ◽  
Tasneem Gul Kazi ◽  
Nida Fatima Kolachi ◽  
Imran Afridi ◽  
Naeem Ullah
Keyword(s):  
Sequential Extraction ◽  
Thermal Power ◽  
Electrothermal Atomic Absorption Spectrometry ◽  
Total Content ◽  
Standard Addition ◽  
Absorption Spectrometry ◽  
Soil Samples ◽  
Bcr Sequential Extraction ◽  
Sequential Extraction Method ◽  
Agricultural Areas

Abstract A rapid ultrasound accelerated sequential extraction (USE) procedure was used to develop chemical partitioning of vanadium (V), proposed by the Community Bureau of Reference/European Union Measurement and Testing Programme (BCR). The effects of ultrasonic treatment on the extraction of V in different soil samples collected from the vicinity of a thermal power plant and agricultural areas of Sindh, Pakistan, were evaluated. In the conventional BCR-sequential extraction method, each extraction step takes 16 h. With the use of ultrasound energy, Steps 1–3 of the USE procedure (excluding the hydrogen peroxide digestion in Step 3, which was performed conventionally) could be completed in 45, 40, and 45 min, respectively. Analysis of the extracts was performed by electrothermal atomic absorption spectrometry. The total contents of V were obtained by digestion with two acid mixtures: H2O2–HF–HNO3–H2SO4 and HClO4–HF–HNO3–H2SO4. Validation was performed by the standard addition technique. Results obtained for each fraction by both methods were statistically compared; no significant differences were found (P < 0.05). The accuracy of the USE procedure was checked by comparing the sum of the V contents in the three fractions and residue with the total content of V. The results of this work provide information on the chemical composition, distribution, and potential mobility of the V in different soils.

scholarly journals Speciation And Mobility Study Of Selected Heavy Metals In Kofe Dumpsite Soil Of Jimma Town, Jimma, Ethiopia

1970 ◽  
Vol 10 (5) ◽  
pp. 629-641
Author(s):  
Kassim Kedir ◽  
Abera Gure ◽  
Yared Merdassa
Keyword(s):  
Heavy Metals ◽  
Sequential Extraction ◽  
Extraction Procedure ◽  
Soil Samples ◽  
High Tendency ◽  
Depth Profiles ◽  
Flame Atomic Absorption ◽  
Bioavailable Fraction ◽  
Jimma Town ◽  
Vertical Mobility

Speciation and mobility of selected heavy metals including Cd, Pb and Fe were investigated in Kofe dumpsite soils of Jimma Town, Jimma, Ethiopia. To study vertical mobility of the metals, soil samples were collected at three depth profiles comprising surface soil (0-10 cm), subsoil (20-30 cm), and bottom soil (40-50 cm) using soil auger. Similarly, for horizontal mobility assessment, soil samples were collected from 5 m, 10 m and 15 m distances starting from the edge of the dumpsite in east, west, north and south directions. Control soil samples were also collected at the same depth profiles, from 200 m away from the dumpsite. The collected samples were air dried, sieved as well as ground before processing utilizing a Community Bureau of Reference (BCR) sequential extraction procedure. The fraction of the target metals in the extracted samples were then determined by flame atomic absorption spectroscopy (FAAS). The mobility factor (%MF) of the target metals was investigated in both vertical and horizontal variations and the obtained results showed that the target metals have exhibited both vertical and horizontal mobility. The texture, organic matter and pH of the soil samples were also analyzed for correlation study. Variation among obtained results, i.e., %MF and concentration of analytes, were evaluated using one way ANOVA at (P<0.05). It was observed that Cd and Pb exhibited vertical mobility and thus could lead to pollution of the underground water. Similarly, the highest amount of Pb in the bioavailable fraction may also indicate its horizontal mobility and its high tendency to pollute surface water, sediment as well as agricultural products.Key Words: Speciation, Mobility, Sequential extraction, Heavy metals

Influence of Inorganic Salts on Concentration of Different Cd Forms in the Soil

2011 ◽  
Vol 356-360 ◽  
pp. 943-950
Author(s):  
Pei Yu Liang ◽  
Yong Jie Tan ◽  
Li Jun Chen ◽  
Wei Ke Li
Keyword(s):  
Sequential Extraction ◽  
Sodium Salt ◽  
Extraction Procedure ◽  
Soil Samples ◽  
Sequential Extraction Procedure ◽  
Inorganic Salts ◽  
Carbonate Content ◽  
High Concentration ◽  
Low Concentration ◽  
The Impact

Different soluble inorganic salts were irrigated into batches of soil samples by setting contrastive experiments on the basis of Tessier sequential extraction procedure to study their influences upon Cd forms in the soil. Research shows that all the three salts were able to influence the forms of Cd in the soil: NaCl and Na2SO4added into the soil could increase the contents of exchangeable Cd and the higher the concentration, the greater the impact, while Na2CO3could decrease it by 30.35%(4 g/kg Na2CO3added) and 69.87%(8 g/kg Na2CO3 added). Carbonate content of Cd was influenced obviously by NaCl, with the decrease of 7.30%, 10.52% corresponding to low concentration and high concentration of NaCl, and Na2CO3can increase this form slightly, Na2SO4had little effect, so the content remained unchanged. The Fe-Mn oxidation form of Cd remained the original level when NaCl was added in the samples while it increased with the addition of Na2CO3obviously and the concentration increased 8.67% (4 g/kg Na2CO3added) and 51.85% (8 g/kg Na2CO3added),but it decreased by the effect of Na2SO4. Organic Cd and the residual Cd fluctuated slightly at a very low concentration. The total Cd decreased with the addition of sodium salt.

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