A Study of Influence of Marsh Wetland Reclamation and Cultivation on the Features of Metallic Elements Distribution

摘要

Through gauging the contents of pH,SOM,and metallic elements such as,A1,Fe,Hg,Pb,Cu,and Mn in the soft of typical Deyeuxia angustifolia wetland,corn fields and rice fields on the Sanjiang Plain,using the approach of space as a substitute for time,this paper discusses the contents of metallic elements and changes in the features of their profile distribution after the wetland is developed as farmland.The results showed that after the wetland was developed as farmland,the SOM content in soil would be lowered,with pH impacted significantly.The SOM content was positively correlated with Fe only,while the pH was positively or negatively correlated with most metallic elements in soil.After the wetland was reclaimed as paddy field,pH in soil rose,while A1,Fe,and Pb was enriched,and Mn was lost; after it was reclaimed as dry farmland,pH in soil lowered,while A1,Fe,and Pb were lost,and Mn was enriched.Hg was lost in both dry farmland and paddy field,while the changes in Cu were significant.The wetland reclamation and cultivation led to the change in pH conditions,which might be the main factors causing the changes in the content of soil metallic elements and features of their profile distribution.