赤泥不同施用量在土壤-水稻系统中生态效应的研究

Ecological Effects of Different Application Amount of Red Mud in Soil-Rice System

采用盆栽试验研究赤泥不同施用量在土壤-水稻系统中迁移、积累规律及生态效应。结果表明:在供试土壤中处理2(25g赤泥/10kg土)与其他施用量处理相比较,株高增幅为3.7～10.2cm,每盆粒重增幅为3.3～16.6g。不同处理重金属Pb、Zn和Cd在植物体内各部分的分布为:根>茎>叶>壳>籽粒、根>叶>茎>壳>籽粒、根>茎>叶>籽粒>壳。水稻各部位吸收的Pb、Zn、Cd含量都表现施用赤泥处理为比对照的要低,处理6对降低作物Pb、Zn和Cd含量的效果最好,显著减少了籽粒中重金属含量。各处理重金属的迁移能力由高到低的顺序为:Cd>Zn>Pb,六个处理比较,随着赤泥用量的增加,Cd、Zn和Pb的迁移能力越低。综合考虑水稻产量、经济效益和品质认为在供试土壤上按25g赤泥/10kg土施用赤泥较为合适。

The laws of migration and accumulation and ecological effects of different application amount of red mud in soil-rice system were studied by pot experiments. The results showed that the crops increased 3.7 - 10.2 cm in plant height and 3.3 - 16.6 g in grain weight of each pot in treatment 2 （25 g red mud per 10 kg soil） than which in the others treatments. The concentration of Pb, Zn and Cd in each part of plant under different treatments were arranged as follows： Pb was root〉stem〉leaf 〉hull〉seed; Zn was root〉leaf〉stem〉hull〉seed; Cd was root〉stem〉leaf〉 seed〉hull. The concentrations of Pb, Zn and Cd in each part of plant under the treatments of red mud application were all lower than which in the control. The effect of treatment 6 decreased the concentration of Pb, Zn and Cd in crops was the best, the contents of heavy metals in seed were significantly decreased. The migration ability of heavy metals was in the order as Cd〉Zn〉Pb, and the migration ability of Cd, Zn and Pb was decreased with increasing application amount of red mud in all six treatments. Integrated considering the yield, economic benefit and quality of rice, the application amount of 25 g red mud per 10 kg soil is the best.