Pb超富集植物对营养元素N、P、K的响应

Effects of nutrient elements on the lead uptake by hyperaccumulators

利用富集重金属或对重金属具有耐性的植物修复重金属污染土壤,是治理土壤重金属污染的新途径。本研究通过温室土培方法,研究了营养元素N、P、K对3种Pb超富集植物绿叶苋菜、紫穗槐和羽叶鬼针草生长发育及Pb吸收的影响。结果表明,少量的N和K会促进富集植物叶片叶绿素值和干质量的增加,促进植物对Pb的吸收;随着N和K水平的增加,虽然叶绿素值和干质量一直在增加,但植物对Pb的吸收能力降低;K对植株Pb的吸收能力的抑制作用不如N显著。土壤供P会降低植物对Pb的吸收,且下降极显著。少量的N、P、K均使富集植物中的Pb迁移总量增加,高质量分数时则抑制。但K的抑制作用不如N及P的显著。

Choosing and using plants as hyperaccumulators to remediate soils contaminated by heavy metals is a new technique. Three plants (Amaranthus tricolor, Sophora japonic and Bidens maximowicziana) were studied in the authors research with pot exper[(i)(m)]ent in a green-house. This paper deals with the effects of nutrient elements on lead uptake by hyperaccumulators. The results show that the low levels of nitrogen and potassium can increase in chlorophyl and dry mass of hyperaccumulators, improve their uptake of lead, but with the increase in nitrogen and potassium levels, the uptake of Lead by plants declines, although chlorophyl and dry mass increase gradually. The results also show that the low levels of N, P and K all can increase the total transportation amount of lead in the plants, but the high levels of them can inhibit the transportation. And the control of K is not as important as P and N.[( )-236.8( )]