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Mahtab Ahmad Sang Soo Lee Sung Eun Lee Mohammad I. Al-Wabel Daniel C. W. Tsang Yong Sik Ok 《Journal of Soils and Sediments》2017,17(3):717-730
Purpose
Remediation of metal contaminated soil with biochar is attracting extensive interest in recent years. Understanding the significance of variable biochar properties and soil types helps elucidating the meticulous roles of biochar in immobilizing/mobilizing metals/metalloids in contaminated soils.Materials and methods
Six biochars were produced from widely available agricultural wastes (i.e., soybean stover, peanut shells and pine needles) at two pyrolysis temperatures of 300 and 700 °C, respectively. The Pb-, Cu-, and Sb-contaminated shooting range soils and Pb-, Zn-, and As-contaminated agricultural soils were amended with the produced biochars. The mobility of metals/metalloids was assessed by the standard batch leaching test, principal component analysis and speciation modeling.Results and discussion
The changes in soil properties were correlated to feedstock types and pyrolysis temperatures of biochars based on the principal component analysis. Biochars produced at 300 °C were more efficient in decreasing Pb and Cu mobility (>93 %) in alkaline shooting range soil via surface complexation with carboxyl groups and Fe-/Al-minerals of biochars as well as metal-phosphates precipitation. By contrast, biochars produced at 700 °C outperformed their counterparts in decreasing Pb and Zn mobility (100 %) in acidic agricultural soil by metal-hydroxides precipitation due to biochar-induced pH increase. However, Sb and As mobility in both soils was unfavorably increased by biochar amendment, possibly due to the enhanced electrostatic repulsion and competition with phosphate.Conclusions
It is noteworthy that the application of biochars is not equally effective in immobilizing metals or mobilizing metalloids in different soils. We should apply biochar to multi-metal contaminated soil with great caution and tailor biochar production for achieving desired outcome and avoiding adverse impact on soil ecosystem.2.
The antioxidant status of rats experimentally infected with Trypanosoma evansi isolated from a camel was studied using established parasitological, haematological and biochemical methods. The results indicated that infections in all rats resulted in a fulminating parasitaemia. Changes in blood parameters in T. evansi-infected rats indicated leukocytosis and a macrocytic hypochromic anaemia. A degree of anisocytosis was also observed. The activities of plasma glucose-6-phosphate dehydrogenase and glutathione peroxidase in whole blood of infected rats were significantly higher (p<0.05 and p<0.001, respectively) compared with control. No statistically significant difference was observed in the activity of superoxide dismutase in infected and control rats. Results obtained indicated that trypanosomosis caused oxidative stress and induced antioxidant enzymes. 相似文献
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Al-Wabel NA 《Polish journal of veterinary sciences》2008,11(1):63-66
Semicarbazide-sensitive amine oxidase (SSAO) activity was measured spectrophotometrically using benzylamine as a substrate, in the serum of healthy males and females of horses, camels, cattle, sheep and goats. The animals were born and raised in the same area, and the blood collection was made on the same day to avoid variations. Also the concentrations of protein and copper were measured in the same samples. There were no significant gender-related differences in SSAO activity between the tested animals regardless of species. Activities of SSAO in either male or female of horse were significantly different (p < 0.05) from the remaining tested animals. The highest activities (expressed as micromole of benzaldehyde production/mg protein/hr) were found in horses (9.592 and 9.458), followed by camels (3.226 and 2.407), cattle (1.014 and 1.648), goat (0.750 and 0.572) and sheep (0.435 and 0.244). Insignificant higher activities of SSAO were noted in all males of the tested animals compared to that in females except in cattle. The results suggest that horses are endowed with a very high activity of this enzyme amounting to 3-21 times higher than that found in large and small ruminants. There were no significant differences between the levels of protein and copper in either sex of all the tested species. 相似文献
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Rafique Muhammad Imran Usman Adel R. A. Ahmad Munir Sallam Abdelazeem Al-Wabel Mohammad I. 《Journal of Soils and Sediments》2020,20(1):330-339
Journal of Soils and Sediments - Tannery waste–contaminated soil has a high amount of several toxic chemicals and heavy metals including chromium (Cr), which makes it unsuitable for... 相似文献
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Meththika Vithanage Tharanga Bandara Mohammad I. Al-Wabel Adel Abduljabbar Adel R. A. Usman Mahtab Ahmad 《Communications in Soil Science and Plant Analysis》2018,49(5):635-643
Woody biochars derived by pyrolyzing Gliricidia sepium at 300°C and 500°C and a waste byproduct of same biomass from a bioenergy industry (BC700) were tested for their effect on soil enzymes activities and available form of heavy metals in multi-metals contaminated soil. Pot experiments were conducted during 6 weeks with tomato (Lycopersicon esculentum L.) at biochar application rates, 1, 2.5, and 5% (w/w). A reduction in polyphenol oxidase with biochars produced at increasing pyrolysis temperature compared to the control whereas the maximum activity of dehydrogenase and catalase was observed in 1% BC500 and 2.5% BC300, respectively. Soil available form of Ni, Mn, and Cr were reduced by 55, 70% and 80% in 5% BC700 amended soil, respectively. The highest geometric mean of enzyme activities was observed in 2.5% BC300 treatment. Overall the application of high dosages of high temperature derived biochar masks/deteriorates soil enzyme activities but immobilizes bioavailable heavy metals and reduces toxicity. 相似文献
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Alaa Ibrahim Adel Rabie Ahmed Usman Mohammad Ibrahim Al-Wabel Mahmoud Nadeem Yong Sik Ok 《Archives of Agronomy and Soil Science》2017,63(2):185-197
A laboratory column experiment was conducted to investigate the effects of 400°C biochar at application rate of 15 g kg?1 (21.9 t ha?1) with different particle sizes (<0.5 mm (S1), 0.5–1 mm (S2) and 1–2 mm (S3)) and application depths (0–2 cm depth (D0), 4–6 cm depth (D5) and 8–10 cm depth (D10)) on hydro-physical properties of sandy loam soil. The results indicated that applying biochar decreased the waterfront and saturated hydraulic conductivity of sandy loam soil. The cumulative evaporation was the highest and amounted to 40.9 mm in the non-treated soil, but it recorded the lowest amount of 32.2–35.5 mm in the biochar-treated soil. Applying biochar caused significant increases in the amount of conserved and retained water with the highest amount of water conserved in soil treated with S2 biochar at D5. Moreover, the cumulative water infiltration through the soil was significantly reduced by S1 and S2 biochars at D0. The values of saturated hydraulic conductivity for biochar treatments were significantly lower than those for the control, with the lowest values for S1 at D0 and D5. These results suggest positive improvement for the hydro-properties of coarse-textured soils following biochar addition, especially with finer particles of biochar. 相似文献
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Indika Herath M. C. M. Iqbal Mohammad I. Al-Wabel Adel Abduljabbar Mahtab Ahmad Adel R. A. Usman Yong Sik Ok Meththika Vithanage 《Journal of Soils and Sediments》2017,17(3):731-740
Purpose
This study was aimed to investigate the potential of biochar (BC), a waste byproduct of a bioenegy industry, Sri Lanka, as a soil amendment to immobilize and reduce the phytotoxicity of Cr in tannery waste-polluted soil (TWS).Materials and methods
The TWS and bioenergy waste BC were characterized for physio-chemical parameters. A pot experiment was conducted by adding three BC application rates, 1, 2.5, and 5 % (w/w) to investigate the immobilizing capacity and bioaccumulation of chromium (Cr) in tomato plants (Lycopersicon esculentum L.). Soils and plants were digested via microwave digestion and analyzed for total Cr. Further, sequential extraction was conducted to assess the fractionation of Cr before and after the application of bioenergy waste BC on TWS.Results and discussion
The total Cr concentration in TWS was 12,285 mg/kg. The biomass of tomato plants grown in the 5 % BC amendment doubled compared to the biomass in BC-unamended soil. Bioaccumulation of Cr in plants grown in 5 % BC-amended TWS showed a decrease by 97 % compared to that of the BC-unamended soil. The CaCl2 extractability of Cr indicated that the bioavailability of Cr in the 5 % BC amendment has decreased by 68 % compared to the control. Sequentially extracted Cr in the exchangeable fraction decreased by 98 % in the 5 % BC amendment.Conclusions
Pore diffusion, and adsorption via π-π electron donor-acceptor interactions were the primary mechanisms to be involved in the Cr retention in BC. Results suggested that the addition of BC to TWS reduces the mobility, bioavailability, and phytotoxicity of Cr in tomato plants.
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