中文摘要：

研究了硫化钠用于固定土壤中铅镉的可行性，考察了硫化钠用量及土壤pH、有机质对固定过程中土壤铅、镉赋存形态及固定效果的影响。结果表明，添加硫化钠可改变土壤中铅镉的形态分布，明显降低可交换态铅镉的含量。条件适当时，铅镉可交换态下降值分别为63％和73％。硫化钠在固定铅的过程中，固定效率对土壤pH、有机质含量的变化较为敏感，在有机质含量较低或酸性土壤中，硫化钠对铅固定效率较高；相对于铅，有机质含量和pH变化对镉的固定效率影响不是很大。

英文摘要：

In order to study the feasibility of sodium sulfide that used to immobilize lead and cadmium, some parameters such as sodium sulfide dosage, soil pH, organic matter content in the immobilization process and fraction distribution of lead and cadmium in soil were investigated. The results show that the addition of sul- fide can change the fraction distributions of lead and cadmium in the soil, reduce exchangeable fraction of them significantly. When conditions are appropriate, the decrease values of exchangeable fraction about lead and cad- mium are 63% and 73% , respectively. In the immobilization process, the changes of soil pH, organic matter content have great influence on the process of lead immobilization. The results show that there are high immobi- lize effieiencies in acid soil or low organic matter content soil. Compared to the lead, organic matter content and soil pH have little impact on cadmium-immobilize efficiency.