Growth And Accumulation Effect Of Jatropha Curcas In Soil With Different Water And Heavy Metal Treatment

With the continuous development of social economy,environmental pollution is getting serious,soil contamination with heavy metals becomes a global problem that should pay attention to,which is not beneficial for ecological civilization construction and sustainable development of economy and society.The varied of remediation methods for soil contaminated with heavy metals,for traditional remediating way of physical-chemistry,the disadvantages of those are high investment cost,while phytoremediation is the most effective way until now.However,in terms of current phytoremediators,common defects such as small biomass,slow growth,which are the key to limiting phytoremediation in scale even to commercial application.To solve this problem,researchers have proposed all sorts of supplementary measures to strengthen the plant's ability to repair soil heavy metal pollution,however,the water regulation on phytoremediation of heavy metal contaminated soil has not yet reported via trial.Water plays an important role for the growth of plants,in terms of plant physiology,moisture regulation have important effects on extracting soil heavy metals through plants,and it is one aspect that should be pay great attention to phytoremediation.Water resource crisis becoming seriously in our country,and area of soil contaminated by heavy metals expands unceasingly,for strong drought resistance ability,high biomass,economic and practical value of Jatropha curcas.The paper was conducted under different irrigation amounts and different heavy metal concentrations.The results showed that,(1)With the increase of cadmium concentration,the translocation factor,bioconcentration factor significantly reduced,while cadmium content in Jatropha curcas increased obviously,and cadmium accumulated in its organs was ordered:root>stem>leaf.Jatropha curcas survived in WlCd3 treatment with lesser irrigation amount and higher cadmium concentration,exhibiting a strong capacity to resist drought and cadmium stress.Under the research condition,irrigation amount of W3(70%FC)was conductive to Jatropha curcas growth and accumulation for soil cadmium.(2)With the increase of zinc concentration,the translocation factor and bioconcentration factor decreased,while zinc content in Jatropha curcas increased significantly.In the treatment of Z1 and Z2,the zinc accumulated in different organs of the plant was ordered:root>stem>leaf.In comparison with the control(ZO),the growth,water storage capability of different organs and ability of translocating as well as bioconcentration soil zinc of Jatropha curcas was restricted in Z1 and Z2 treatments.W2 was more conductive to growth of Jatropha curcas and uplift of translocation as well as bioconcentration factor.Under the research condition,irrigation amount of W2(70%FC)was conductive to Jatropha curcas growth and accumulation for soil zinc.(3)In comparison with NiO,the change amount of plant height and stem diameter,daily variation of Pn and Rt,seedling healthy index,Huber value,water storage ability of per unit dry matter mass,total dry matter mass and Ei,w,u were all significantly decreased in Nil and Ni2 treatments.Meanwhile,daily variation of Pn,seedling healthy index,Huber value,water storage ability of per unit dry matter mass,total dry matter mass and Ei,w,u were all significantly decreased in Nil than Ni2,namely the inhibition of Ni concentration on plant growth in Ni2 was stronger than that in Ni1,the largest soil nickel concentration that was beneficial to Jatropha curcas growth is 500 mg/kg under the research condition.