Abdelhafez Ahmed A, Li Jianhua, Abbas Mohamed H H
Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Environmental Research Department, Soils, Water and Environment Research Institute (SWERI), Agricultural Research Center (ARC), Giza, Egypt.
Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
Chemosphere. 2014 Dec;117:66-71. doi: 10.1016/j.chemosphere.2014.05.086. Epub 2014 Jun 24.
The main objectives of the current study were to evaluate the potential effects of biochar derived from sugar cane bagasse (SC-BC) and orange peel (OP-BC) on improving the physicochemical properties of a metal smelter contaminated soil, and determining its potentiality for stabilizing Pb and As in soil. To achieve these goals, biochar was produced in a small-scale biochar producing plant, and an incubation experiment was conducted using a silt loam metal-contaminated soil treated with different application rates of biochar (0-10% w/w). The obtained results showed that, the addition of SC-BC and OP-BC increased significantly the soil aggregate stability, water-holding capacity, cation exchange capacity, organic matter and N-status in soil. SC-BC considerably decreased the solubility of Pb to values lower than the toxic regulatory level of the toxicity characteristics leaching procedure extraction (5 mg L(-1)). The rise in soil pH caused by biochar application, and the increase of soil organic matter transformed the labile Pb into less available fractions i.e. "Fe-Mn oxides" and "organic" bound fractions. On the other hand, As was desorbed from Fe-Mn oxides, which resulted in greater mobility of As in the treated soil. We concluded that SC-BC and OP-BC could be used successfully for remediating soils highly contaminated with Pb. However, considerable attention should be paid when using it in soil contaminated with As.
本研究的主要目的是评估甘蔗渣生物炭（SC-BC）和橙皮生物炭（OP-BC）对改善金属冶炼厂污染土壤理化性质的潜在影响，并确定其在稳定土壤中铅和砷方面的潜力。为实现这些目标，在小型生物炭生产厂生产生物炭，并使用不同施用量（0-10% w/w）的生物炭处理粉质壤土金属污染土壤进行培养试验。所得结果表明，添加SC-BC和OP-BC显著提高了土壤团聚体稳定性、持水能力、阳离子交换能力、土壤有机质和氮素状况。SC-BC显著降低了铅的溶解度，使其低于毒性特性浸出程序提取的毒性监管水平（5 mg L(-1)）。生物炭施用导致土壤pH值升高，土壤有机质增加，使不稳定的铅转化为有效性较低的组分，即“铁锰氧化物”和“有机”结合组分。另一方面，砷从铁锰氧化物中解吸出来，导致处理后土壤中砷的迁移性增加。我们得出结论，SC-BC和OP-BC可成功用于修复铅污染严重的土壤。然而，在砷污染土壤中使用时应给予相当的关注。
