不同钝化剂对重金属在土壤-油菜中迁移的影响

为比较不同钝化材料对污染土壤-油菜中重金属迁移的影响，通过大田试验，添加海泡石、鸡粪、秸秆腐殖质、生石灰、磷矿粉、磷酸二铵对矿区重金属复合污染耕地进行单一和混合处理，栽种油菜，分析不同处理方式对重金属生物迁移和积累的影响。结果表明，单一处理中，海泡石均有效降低了土壤中5种重金属的有效态含量，鸡粪有效降低了土壤中As、Pb、Cd和Zn 4种重金属的有效态含量。海泡石+鸡粪处理组土壤中Pb、As、Cd、Zn和Cu的有效态含量分别是空白对照组的56.99%、40.84%、43.06%、78.33%和52.23%。油菜根中As的平均含量分别约是茎、果壳和种子的2.13、3.33倍和12.45倍，海泡石+鸡粪处理对降低种子中As的含量效果最佳，约是空白对照组的57.07%，其次是海泡石+腐殖质处理组。海泡石+鸡粪处理组油菜种子中Pb的含量最低，为空白组的13.26%。海泡石+鸡粪处理组种子中Cd的含量仅为对照组的44.02%。除了腐殖质，其他处理方式均有效减少了油菜各器官中Zn的含量。所有处理方式均显著降低了油菜各器官中Cu的含量（P<0.05）。油菜根和种子中As的含量与土壤中As的有效态含量呈显著正相关关系（P<0.05）；土壤Cd的有效态含量极显著影响了茎中Cd的含量（P<0.01），果壳与根中Cd的含量为极显著相关关系（P<0.01）。土壤中Pb、Zn和Cu的有效态含量对油菜各器官中的相应重金属含量未造成显著影响。土壤添加改良材料处理对于限制油菜吸收、转移和积累Zn、Cu效果最显著，As最差。海泡石与其他材料混合处理的钝化效果总体优于单一材料，海泡石和鸡粪混合钝化重金属活性效果最佳。

Effects of different immobilization materials on heavy metal migration in contaminated soil-rape

In rape plant(Brassica napus), to compare and analyze the influences of different immobilization materials on the migration and accumulation of heavy metals in contaminated soil, different treatments including sepiolite, chicken manure, straw humus, quicklime, phosphate, and diammonium phosphate were added singly or simultaneously into the cultivated compound contaminated land in a mining area. The results showed that sepiolite effectively reduced the available content of Cu, As, Pb, Cd, and Zn in the soil, and chicken manure effectively reduced the available content of As, Pb, Cd, and Zn in the soil. The available contents of Pb, As, Cd, Zn, and Cu in the sepiolite + chicken manure treatment group were 56.99%, 40.84%, 43.06%, 78.33%, and 52.23% of that in the control group, respectively. The average content of As in rape root was about 2.13, 3.33, and 12.45 times that in the stem, fruit shell, and seed, respectively. Sepiolite + chicken manure treatment had the best effect on reducing the content of As in seeds, which was about 57.07% of that in the control group, and the next was sepiolite + humus treatment. The content of Pb in the seeds in the sepiolite + chicken manure treatment groups was the lowest, which was only 13.26% of that in the control group. The content of Cd in the seeds in the sepiolite + chicken manure treatment groups was only 44.02% of that in the control group. In addition to humus, all the other treatments could effectively reduce the content of Zn in rape organs. The content of Cu in rape organs was also significantly reduced by all the treatments(P<0.05). There was a significant positive correlation between the content of As in rape root and seed and the available content of As in the soil(P<0.05). The available content of Cd in the soil significantly affected the content of Cd in the stem(P<0.01)and significantly correlated with the content of Cd in the shuck and root(P<0.01). The available contents of Pb, Zn, and Cu in the soil had no significant effect on the content of the total heavy metal in rape organs. In summary, the addition of immobilization material treatments has the most significant effect on limiting the absorption, transfer, and accumulation of Zn and Cu in rape, while it has the least limiting effect on those of As. The passivation effect of sepiolite mixed with other materials on heavy metals is more effective than that of a single treatment, among which sepiolite + chicken manure treatment has the best passivation effect.