施磷方式对蓖麻生长和铅积累的影响

采用盆栽实验研究了土壤重金属铅污染下（1 000mg·kg-1）,磷肥根施和根施配合叶面喷施两种方式对能源作物蓖麻生长和铅积累特征的影响。结果表明,根施磷肥对蓖麻形态和生物量影响很小,而根施配合叶面喷施显著地提高了蓖麻总生物量。根施磷肥降低了蓖麻地下部对铅的富集,根施配合叶面喷施则大幅度提高了蓖麻叶片对铅的积累量,从而提高了蓖麻地上部的铅积累量,两者与对照相比分别提高了90.01%和79.40%。磷肥根施配合叶面喷施对蓖麻铅富集系数影响很小,但大大提高了转运系数,达0.549,是对照的1.91倍。因此,适当的磷肥根施配合叶面喷施可以有效提高蓖麻铅从根系到地上部的转移能力,从而提高蓖麻对土壤铅的萃取能力和修复效果。

Effects of Phosphate Fertilization Technology on the Growth and Lead Accumulation of Castor

Pot experiments were carried out to investigate the influence of different phosphate fertilizer（P）rates by root fertilization and foliar spraying on the plant growth and accumulation of lead（Pb）in castor when exposed to Pb polluted soil（1 000mg·kg-1）.The results showed that root fertilization had little effects on phytomorph and biomass of castor,while root fertilization combined with foliar spraying increased biomass greatly.Root fertilization decreased concentration of Pb in the root.Root fertilization combined with foliar spraying greatly increased Pb accumulation in leaves,thus promoted Pb accumulation in shoot.They were increased by 90.01%and 79.40%compared to the control,respectively.Root fertilization combined with foliar spraying had little effects on bioaccumulation factor,but greatly increased translocation coefficient up to 0.549,which was 1.91times of the control.Therefore,appropriate root fertilization combined with foliar spraying of phosphate can improve the translocation ability of Pb from root to shoot by castor,thereby improving the extraction ability and phytoremediation efficiency of lead contaminated soil by castor.