赤泥对污染土壤中Cd,Pb和Zn形态及水稻生长的影响

通过盆栽试验,研究了赤泥对污染土壤中Cd,Pb和Zn形态和水稻糙米中Cd,Pb和Zn含量以及水稻生长的影响。结果表明,添加赤泥可有效提高土壤pH,改变土壤中Cd,Pb和Zn的形态,显著降低土壤中交换态Cd,Pb和Zn含量以及水稻糙米中的Cd,Pb和Zn含量。当赤泥施用量为12.5 g kg-1土时,土壤中交换态Cd,Pb和Zn的含量分别比空白对照降低了40.81%、25.68%和38.48%;水稻糙米中Cd,Pb和Zn的含量分别比空白对照降低了70.45%、42.46%和29.19%。与空白对照相比,赤泥施用量为5.0 g kg-1土时,水稻株高、穗长及每盆粒重均显著提高。但当赤泥施用量超过10.0 g kg-1土时水稻生长会受到抑制。在赤泥农业应用时应考虑其施用量及潜在的环境风险,以免影响作物生长。

Effects of Red Mud Addition on Fractions of Cd,Pb and Zn and Rice Growth in Contaminated Soil

Pot experiment was conducted in contaminated soil to investigate the effects of red mud addition on Cd,Pb and Zn fractions,uptake of Cd,Pb and Zn by rice grain and rice growth.The results showed that red mud application increased the soil pH,changed the fractions of Cd,Pb and Zn in soil,while the soil exchangeable Cd,Pb and Zn contents and the Cd,Pb and Zn contents in rice grain decreased significantly.Compared with the control,the treatment with 12.5 g red mud per 1 kg soil decreased the soil exchangeable Cd,Pb and Zn by 40.81%,25.68% and 38.48%,while the Cd,Pb and Zn contents in rice grain decreased by 70.45%,42.46% and 29.19%.Compared with the control,the treatment with 5.0 g red mud per 1 kg soil increased the height of rice,length of ear and grain weight per pot significantly.If the red mud addition rate was over 10.0 g per 1 kg soil,the rice growth was restrained.It is necessary to consider the amount of red mud application,as not to affect the crop growth.