Figure 4
Linear regressions of Pb, Cu, Zn and Mn with Fe in the root tissue with iron plaque and the regular root dermal tissue. The T. latifolia L. samples were collected in 2010 and 2011, respectively. Regression line (I) is for the dermal root tissue with Fe plaque, and regression line (II) is for the regular root dermal tissue. Filled circles: regular root dermal tissue. Open circles: root dermal tissue with Fe plaque. Black lines: linear regression lines. Green dashed lines: 95% confidence level. Red dashed lines: 95% prediction band. |