大豆和小麦对土壤中汞的吸收与富集研究

为了探讨不同作物对汞吸收和富集特征，在盆栽条件下，研究了大豆和小麦在汞添加量为0~3.0 mg/kg的土壤中生长及对汞的吸收与富集特征。结果表明，随外源汞添加量增加，大豆株高、单盆籽粒数、根系和地上部汞含量均无明显变化，但小麦株高和单盆籽粒数会降低，根系和地上部汞含量会增加。适量低浓度汞均能促进2种作物的单盆产量增加。相同汞添加量的条件下，地上部汞含量均为大豆＞小麦，而根部汞含量在较低汞添加量时为大豆＞小麦，较高汞添加量时为小麦＞大豆。2种作物对汞的转移系数则表现为在不添加汞的土壤中小麦＞大豆，而在添加汞的土壤中大豆＞小麦。大豆不同部位的汞富集系数表现为：根＞茎＞叶。小麦空白处理各部分的富集系数为茎叶＞根，其他处理为根＞茎叶。

Uptake and Accumulation Characteristics of Mercury by Soybean and Wheat in Soil

In order to confirm the uptake and accumulation characteristics of mercury by crops, a pot experiment was conducted to study the growth, uptake and accumulation characteristics of mercury by soybean and wheat planted in the soil with mercury dosage of 0-3.0 mg/kg. The results showed that: adding mercury to the soil reduced the plant height and the grain numbers of wheat, and the mercury content of roots and shoots of wheat gradually increased. However, no significant impact was found on soybean. In addition, appropriate amount of low concentration of mercury could increase the grain weight per pot of the two crops. On the other hand, the mercury content of shoots of soybean was higher than wheat, which of roots showed the same rule in soil with low concentration of mercury. But the mercury content of roots of wheat was higher than soybean in soil with high concentration of mercury. The translocation factors (TF) of the wheat was higher than soybean in soil with no mercury added, which of the soybean was higher in soil with mercury added. The bio-concentration factors (BCF) of soybean were in the following order: root＞stem＞leaf. BCF of wheat in soil with no mercury added was stem and leaf＞root, which was root＞stem and leaf for other treatments.