Study On Chelating Agents And Plant Hormone Remediation Of Heavy Metal Contaminated Soil By Hyperaccumulator

With the rapid development of industry and economy,soil pollution has been increasingly serious,lead to soil pollution occur constantly in environmental problems and human body disease.But hyperaccumulators repair has been in the stage of research used to the small plant biomass,long repair cycle.Therefore,studying a kind of effective reinforcement measures to increase the effect of phytoremediation is research hotspot.Through the soil leaching experiment studies four kinds of additives that GLDA,EDTA,EDDS,CA for extraction effect and the extraction rate on the soil heavy metal that Cu,Cd,Zn.Through the potted experiment research GLDA and IAA for Sedum alfredii and solanum nigrum effect that growth status and enrichment on soil heavy metals,and availability of heavy metal in rhizosphere soil and non-rhizosphere soil.This paper main conclusion:(1)Through soil extraction experiment,it was found that all chelators had theextraction ability for Cd、Cu and Zn in soil,the rank of each chelatorfor extraction effects for Cd was GLDA>EDTA>EDDS>CA;Continuous extraction of soil,the best effect of EDTA on the extraction of heavy metal Cu and Zn,GLDA inferior it.the best effect of GLDA on the extraction of heavy metal Cd,EDTA inferior it.Four kinds of additives for different heavy metal extraction rate of order for Cd > Cu >Zn.(2)In soil extraction experiment,Cd existed mainly in AE、Red and Res form in the original soil through improved BCR sequential extraction procedure,four kinds of additives extraction order was AE> Red >Oxi>Res for heavy metal Cd,Cu and Zn in soil.(3)Biodegradable chelator GLDA and plant hormones IAA Can affect the growth and biomass of hyperaccumulation plants.Compound applied effect is better than single applying.When adding G2:I3 in shoots of and in roots of plant biomass maximum(P <0.01)for Sedum alfredii experiment.That increased by 43.42% and 45.45% compared to the control.Compound applied effect is better than single applying.When adding G2:I2 in shoots of and in roots of plant biomass maximum(P <0.01)for solanum nigrum experiment.That increased by 59.09% and 33.98% compared to the control.(4)Biodegradable chelator GLDA and plant hormones IAA Can affect on concentration of heavy metal in hyperaccumulation plants,When adding G2:I3 the content heavy metal that Cd、Cu、Zn in roots of plant maximum(P <0.01)for Sedum alfredii experiment.That increased by 1.69,2.04,2.32 times compared to the control.When adding G2:I2 the content heavy metal that Cd、Cu、Zn in roots of plant maximum(P <0.01)for solanum nigrum experiment.That increased by 1.70 、1.67、1.57 times compared to the control.(5)Biodegradable chelator GLDA and plant hormones IAA Can affect accumulation of heavy metal of Sedum alfredii and solanum nigrum.When adding G2:I3 the accumulation of heavy metal that Cd、Cu、Zn in plant maximum(P <0.01)for Sedum alfredii experiment.That increased by 2.48、3.02、3.43 times compared to the control.When adding G2:I2 the accumulation of heavy metal that Cd、Cu、Zn in plant maximum(P <0.01)for solanum nigrum experiment.That increased by 2.70、2.67、2.50 times compared to the control.