Study On The Transport Enrichment Of Different Types Of Heavy Metals In Iris Sibirica L.

With the rapid development of industry and agriculture,heavy metals are becoming more and more serious in soil-plant-environment system.Humans have taken various methods for remediation of heavy metal polluted environments.Among them,phytoremediation is a research hotspot.Through the extraction,fixation,and volatilization of heavy metals by plants,the reduction or removal of heavy metals in soil is not only cost-effective,but also it will cause secondary pollution to the environment and is a recognized green repair technology that has received much attention.In this paper,we studied the growth status,biomass,heavy metal content,concentration coefficient,transport coefficient of the six kinds of heavy metals in wetland plants Iris sibirica L.,such as Ni,Co,Pb,Ce,Fe and Cd+humic acid in wetland plants,and studied the transport and enrichment capacity of different types of heavy metals,SOD,CAT and POD,and to provide theoretical reference for the enrichment of heavy metals in plants.Based on the experimental results,the main conclusions of this paper are listed as follows:?1?The study of hydroponics showed that Ni,Co,Pb,Ce,Fe and Cd had a certain inhibitory effect on the growth of Iris sibirica L.,and the absorption and accumulation of different heavy metals in Iris sibirica L.were different.When Ni is 300 mg·L^-1;Co is 500 mg·L^-1;Pb is 300 mg·L^-1;Ce is 800 mg·L^-1;Fe is 400 mg·L^-1,When Cd is 25mg·L^-1,and 200 mg·L^-1 humic acid was added,the corresponding metal concentration in the parts of Iris sibirica L.exceeded 1000 mg·kg^-1.?2?Corresponding to the absorption of heavy metals by plants,the heavy metals absorbed by Iris sibirica L.from the hydroponics solution accumulate primarily in the roots and migrate upward to the stem and leaf,which varies according to the nature of the heavy metals.In this experiment,the concentration of heavy metals 300 mg·L^-1,in the Iris sibirica L.,BCF is Ni>Co>Fe>Pb>Ce,TCF is Ni>Co>Pb>Fe>Ce,the concentration of heavy metals 500 mg·L^-1,BCF is Fe>Co>Ni>Ce>Pb,TCF is Ni>Fe>Co>Ce>Pb.With the increase of HA concentration,the BCF and TCF of Cd²⁺in Iris sibirica L.increased first and then decreased.?3?In this study,we found that the SOD,CAT and POD in the body produced by Ce,Fe,and HA+Cd were found to have different trends with the increase of Ce³⁺,Fe²⁺and HA in Iris sibirica L.The activity of SOD,CAT and POD in plant organs was correlated with the concentration of heavy metal Ce,Fe,and HA.With the increase of heavy metal Ce³⁺and Fe²⁺concentration,SOD activity showed root>stem>leaf.With the increase of HA concentration,CAT increased and decreased,and POD vitality gradually decreased.?4?Chelating agent can form complexes with heavy metal ion,complexes by the absorption of root system and through transport:cells to the ground part,further strengthen the plant roots to the ground part of enrichment of heavy metals transport.With the increase of adding the HA concentration in the Iris sibirica L.of BCF gradually reduce,chelating agents inhibit the ability of transporters transport of heavy metals,shows that high concentrations of biological chelating agent hinder the formation of metal ligand chelating agent,results in the decrease of absorbing ability of soil heavy metal.