College of Resources and Environmental Sciences,Agricultural University of Hebei,Baoding,College of Resources and Environmental Sciences,Agricultural University of Hebei,Baoding,College of Resources and Environmental Sciences,Agricultural University of Hebei,Baoding,College of Resources and Environmental Sciences,Agricultural University of Hebei,Baoding,College of Resources and Environmental Sciences,Agricultural University of Hebei,Baoding
采用土壤培养方法,研究了不同含砷水平土壤中添加外源磷或有机质对砷在板蓝根地下部和地上部累积与分配的影响.结果表明,在外源添加磷或者有机质的情况下,与自然土相比含砷土对板蓝根的生长有一定的促进作用;在自然土(13.4 mg/kg)中,外源磷没有明显影响板蓝根地下部对砷的累积,却显著降低了砷由地下部向地上部的转运,并且添加200 mg P2O5/kg显著降低了砷在地上部的累积.然而,在含砷土(33.4 mg/kg)中,100 mg P2O5 /kg 处理显著降低了砷在地下部的累积,但随磷用量的增加反而促进了地下部砷的累积;在添加有机质试验中,10 g/kg的有机质显著降低了自然土中板蓝根地下部和地上部对砷的累积,并且砷的吸收能力也明显下降.在含砷土(23.4 mg/kg)中,添加5 g/kg的有机质不仅降低了砷在板蓝根中的富集,而且降低了其对砷的吸收能力,提高了砷由地下部向地上部的转运,但是随着有机质施用量增至10 g/kg,地下部砷含量及其吸收砷的能力均有一定程度的增大.因此,在砷水平较低的自然土壤上种植板蓝根添加200 mg P2O5/kg和10 g/kg的有机质是控制砷在该草药体内积累的适宜用量,而在砷水平较高的土壤上100 mg P2O5 /kg 和5 g/kg的有机质是降低板蓝根体内砷累积的适宜用量.
Rice and drinking water can be the important sources of arsenic (As) for human intake, while little is known about As accumulation in Chinese Herbal Medicines. Soil culture experiments were conducted to investigate the effects of phosphate (P) and organic matter (OM) applications on arsenic uptake by and translocation in Isatis indigotica (Chinese name: Ban Langen), the Chinese Herbal Medicines with roots and leaves, using natural soil and the soil contaminated with arsenic. The results showed that P200 (add 200 mg P2O5/kg in soil) increased root dry weights of Isatis indigotica compared to control (P0) in the natural soil or the soil with arsenic, but had no significant effect on the shoot biomass of Isatis indigotica. OM10 (added organic matter at 10 g/kg) increased root dry weights of Isatis indigotica in the natural soil, but reduced the root and shoot dry weights of Isatis indigotica in the As-contaminated soil; In the natural soil, different P levels did not influence As accumulation in the roots of Isatis indigotica, but reduced As translocation from roots to shoots. Moreover, application of 200 mg P2O5/kg significantly decreased As concentrations in shoots. In the arsenic-contaminated soil, P application had no effect on As levels in the shoots, but the level of 100 mg P2O5/kg reduced the accumulation of arsenic in the roots of Isatis indigotica significantly. However, higher level of P application (200 mg P2O5/kg) increased As concentrations in the root of Isatis indigotica; For organic matter application experiment, OM10 reduced the arsenic accumulation in the roots and shoots of Isatis indigotica and the specific arsenic uptake significantly, and did not influence arsenic translocation in plant grown in the natural soil. However, OM5 (added organic matter at 5 g/kg) decreased arsenic accumulation in the roots and shoots of Isatis indigotica and the specific uptake of arsenic, but increased arsenic transport from roots to shoots in Isatis indigotica grown in As-contaminated soil. When the level of organic matter increased up to 10 g/kg, the root-As level and the specific uptake of arsenic were higher than those of other treatments. Therefore, 200 mg P2O5/kg and 10 g/kg organic matter were suitable to decrease As accumulation in Isatis indigotica growing in natural soil, but 100 mg P2O5/kg and 5 g/kg organic matter were better to reduce arsenic concentrations in this herb medicine grown in As-contaminated soil with arsenic concentrations around 30-40 g/kg.