黄棕壤中铅镉复合污染对莴苣生长和品质的影响

Effects of Cd and Pb Compound Pollution in Yellow Brown Soil on the Growth and Quality of Lettuce

用盆栽试验结合化学分析研究了黄棕壤中镉(Cd)、铅(Pb)复合污染对莴苣生长、品质及重金属元素吸收的影响。结果表明,莴苣对Cd、Pb的吸收相互影响,其程度取决于元素的浓度组合;土壤添加Cd、Pb元素对莴苣的维生素C和硝酸盐含量均有显著或极显著的降低;Cd较Pb易于被莴苣吸收,它们从土壤向莴苣的迁移率大小顺序是Cd>Pb。莴苣对Cd的吸收量随添加量增大而增加,但迁移率呈下降趋势,单一污染与复合污染对土壤重金属元素迁移率的影响无明显差异。铅的迁移率低,莴苣植株含铅量不高。

Pot experiments were conductedand plant analysis was made to study the effects of Cd and Pb on the growth of lettuce and its heavy metal uptake when growing in polluted yellow brown soil. The results showed that the uptake of Cd and Pb by lettuce was affected by both element and the co-existence of the two elements, though the interference between ghe two elements wasn＇t distinct. A variance analysis indicated that there was significant influences of heavy metal addition on the physiological properties and quality of lettuce and its heavy metal content. The removal rate of heavy metals from soil to lettuce was in the order of Cd〉Pb. Cd was more easily taken up than Pb by plants in yellow brown soil. The uptake of Cd by lettuce increased and the removal rate decreased with the increase of CA in soil; there is no obvious difference between the removal rate of soil heavy metals under single pollution and that under compound pollution.