Figure 5: Results of Pearson linear regression analyses of As, Ca, Cr, Cu, Mn, Ni and Zn with Fe in the Spartina alterniflora root epidermis and endodermis.

The significance levels of the correlation are indicated by the p values. As, Ca, Cr, Mn and Zn show significant correlation with Fe (95% confidence level), while Cu and Ni show no significant correlation with Fe (95% confidence level). The results suggest that Fe can scavenge the metals and impact their transport in the root system.