Study on Enrichment Characteristics of Metallic Elements in Wetland Soil Using Haloduric Suaeda Salsas

KeyWord:Suaeda salsas  heavy metal  wetland restoration  bio-concentration

Abstract:

      Based on the experiments of artificial cultivation of Suaeda salsas in coastal wetland of Qinhuangdao,the enrichment characteristics of metal elements with Suaeda salsas were studied through analyzing the contents and changes of different metal elements in wetland soil.The results showed that the contents of Fe,Mn,Cr,Pb and Zn in sediments were relatively high,with their average contents of 8 210.94,110.04,8.78,8.25,10.95 mg/kg,respectively,while the content of Cd was the lowest,with an average value of 0.022 mg/kg.The variation degree for the same metal in the sediment of the wetland was relatively small,and the distribution was more uniform.The contents of heavy metals in Suaeda salsas were different according to different sampling sites,but there was a positive correlation for them with the distribution characteristics of metals in the sediments from each station.The contents of Fe,Mn,Zn and Cu were relatively high,and the contents of Fe,Mn,Ni,Cu,As,Cd and Pb in the roots of Suaeda salsas were higher than those in stems and leaves.The content of Cr was the highest in the stems,and those of Zn,Mo were the highest in the leaves.The roots,stems and leaves of Suaeda salsas had the best enrichment effect on Cd,followed by Mo and Cu,and Suaeda salsas had a poorer enrichment ability to Fe,Mn,Zn,As and Pb,which showed that there were differences for Suaeda salsa in the enrichment and removal rates of different metal elements in the sediment.Study of translocation factors showed that Mo,Zn,Cd and Mn were transferred from the roots to the leaves,while Fe,Ni,Pb,As and Cu were immobilized at the roots of Suaeda salsas.This study could provide a theoretical basis for the remediation of heavy metal pollution in wetlands with Suaeda salsas.