中文摘要：

以甘蔗叶、木薯秆、水稻秸秆和蚕沙为原材料,采用限氧热解法在500℃下制备生物炭,通过室内培养实验,研究在不同培养时间（0,15,30,45d）条件下,生物炭施入潮土（Cd浓度5mg/kg）后对土壤基本性质及土壤中镉（Cd）化学形态的影响,探讨了生物炭修复镉污染土壤的可行性。结果表明：添加生物炭后,土壤pH值和阳离子交换量（CEC）随着培养时间的增加而逐渐增加,而土壤有机碳（SOC）含量则呈先增加至最大值而后缓慢降低的趋势,但仍高于对照。同时,生物炭的施入显著降低了土壤中弱酸可提取态Cd和可还原态Cd含量,提高了可氧化态Cd和残渣态Cd含量,且随着培养时间的延长这种转化趋势更为明显。4种生物炭对潮土中Cd钝化效果表现为蚕沙生物炭〉水稻秸秆生物炭〉木薯秆生物炭〉甘蔗叶生物炭。培养结束（45d）时,与对照相比,添加蚕沙生物炭的土壤中弱酸可提取态Cd含量降低了42.07%,可还原态Cd含量降低了35.19%,可氧化态Cd和残渣态Cd含量分别增加了292.59%和339.29%,从而大大降低了Cd的生物有效性,由此可见,生物炭对镉污染土壤的修复是切实可行的。

英文摘要：

Four kinds of biochars that prepared by sugarcane leaves,cassava straw,rice straw and silkworm excrement at 500 ℃ with limited oxygen supply were selected.Batch experiments were used to investigate the effects of biochars on soil properties and Cd chemical forms in Cd polluted tidal soil（5 mg/kg）which incubated over 0d,15 d,30d,45 d.The aim of this study was to assess the possibility of using these biochars in Cd contaminated soil remediation.The results showed that the soil pH,CEC and SOC were increased after the use of biochars.The contents of weak acid extractable and reducible Cd decreased while the contents of oxidized and reducible Cd increased when adding biochars into soil.There was an obvious performance of such changing trend with experiment time.The remediation effects of biochars on polluted soil were shown as silkworm excrement〉rice straw〉cassava straw〉sugarcane leaves.After 45 days cultivation,when compared to the control experiment,the adding of silkworm excrement reduced weak acid extractable Cd by 42.07%,and decreased reducible Cd by 35.19%,the adding of biochars increased oxidized Cd by 292.59%,and increased residual Cd by 339.29%.In a conclusion,using biochars to remediate heavy metal polluted soil was feasible because of their inactivation effects to heavy metals.