【摘要】 以生物炭为改良剂,采用淹水培养方法研究不同添加量生物炭(BC)处理(1%,3%和5%)对污染土壤Zn、Cd、Pb、Cu有效性及养分含量的影响,并用毒性淋出试验(TCLP)法对其生态风险进行评价。结果表明:与对照相比,添加生物炭土壤中交换态Zn、Cd、Pb、Cu分别降低0.15%～24.11%,1.22%～16.09%,0.47%～21.51%,3.05%～77.30%,且表现为随生物炭施用量的增加其降低程度增大。TCLP态Zn、Cd、Pb、Cu含量分别降低0.74%～21.47%,6.67%～47.62%,2.02%～16.74%,0.29%～21.20%,且表现为随生物炭施用量的增加其降低程度增大。与对照相比,添加生物炭后土壤pH上升(-0.01)～0.35个单位,有机质、铵态氮和硝态氮分别增加0.09%～20.02%,1.59%～38.28%和2.74%～90.14%。土壤pH值与土壤交换态Cu含量呈显著负相关,有机质含量与交换态Zn含量呈显著负相关。淹水条件下污染土壤中施用生物炭可降低重金属Zn、Cd、Pb和Cu的有效性和生态风险,提高土壤养分含量,起到改良土壤作用。更多还原

【Abstract】 Biochar as modifying agent was used to study impacts of applying different amounts of biochar(1%,3% and 5%) to contaminated soil on available concentrations of Zn,Cd,Pb,Cu and nutrition contents under waterlogged condition.This article also assessed immobilization effect by using TCLP(toxicity characteristic leaching procedure).The results showed that application of biochar could effectively reduce the availability of Zn,Cd,Pb and Cu compared with control treatment.Compared with the treatment without biochar,the decreasing rate of concentration of exchangeable Zn,Cd,Pb,and Cu ranged from 0.15% to 24.11%,from 1.22% to 16.09%,from 0.47% to 21.51%,and from 3.05% to 77.30%,respectively,and the decreasing rate decreased gradually as biochar application rate increased.Compared with the treatment without biochar,the decreasing rate of concentrations of Zn,Cd,Pb and Cu extracted by TCLP ranged from 0.74% to 21.47%,from 6.67% to 47.62%,from 2.02% to 16.74%,and from 0.29% to 21.20%,respectively,and its decreasing rate decreased gradually as biochar application rate increased.Besides,as compared with the treatment without biochar,pH value,organic matter,ammonium nitrogen,and nitrate nitrogen of the treatment applied biochar increased by(-0.01)~0.35 units,0.09%~20.02%,1.59%~38.28% and 2.74%~90.14%,respectively.Concentration of exchangeable Cu was significantly negatively correlated with soil pH,and concentration exchangeable Zn was significantly negatively correlated with soil organic matter content.Using biochar in contaminated soil could reduce the availability of Zn,Cd,Pb,Cu and ecological risk under waterlogged condition,and it also could improve the soil nutrient content.更多还原