ABSTRACT

To explore the feasibility of biochar for reducing mobility and bioavailability of heavy metals in different contaminated soils, batch incubation experiments including column leaching and pot experiments were conducted to investigate the effects of biochar input on soil pH, the bioavailability of heavy metals (Cd, Zn, and Pb) and their species in three different contaminated soils treated with different swine biochar application rates. The results show that biochar has more potential for pH improvement in acidic soils than neutral and alkaline soil. After 42 d incubation, the pH values of the acidic soils increased from 5.90 to 7.23, while the pH values of neutral/alkaline soils did not change significantly. The available heavy metals showed a decreasing trend as the biochar application rate increases. The order of the immobilization effect is Pb>Zn>Cd. Possible immobilization mechanisms are mainly ion exchange, complexation, π bond action and precipitation on the surface of biochar.

摘要

为了探索生物炭降低不同污染土壤中重金属的迁移率和生物利用度的可行性，进行了分批培养实验（包括柱浸和盆栽实​​验），研究了生物炭输入对土壤pH，重金属（镉，锌，锌）的生物利用度的影响。和Pb）及其物种在三种不同的猪生物炭施用量下受污染的土壤中。结果表明，与中性和碱性土壤相比，在酸性土壤中生物炭具有更大的pH改善潜力。温育42天后，酸性土壤的pH值从5.90增加到7.23，而中性/碱性土壤的pH值没有显着变化。随着生物炭施用量的增加，可利用的重金属呈下降趋势。固定作用的顺序为Pb> Zn> Cd。可能的固定化机理主要是离子交换，络合，π键作用和生物炭表面的沉淀。