P-values from the analysis of variance of redox conditions and pH for heavy metal fraction distributions.

<p>P-values <0.05 show significant difference within factors and significant interaction between factors for each heavy metal fraction, separately.</p

Correlation between the percentage distribution of iron and manganese bound nickel (Ni_{reducible fraction}) and residual lead (Pb_{residual fraction}) in oxidized and reduced paddy soil samples in Zhangjiagang County.

<p>*, and ** denote the significant correlation at <i>p</i>≤0.05 and 0.01, respectively.</p

The percentage distribution of each metal fraction in oxidized condition in paddy soil samples in Zhangjiagang County.

<p>L means lower pH (<6), M means moderate pH (6–7), H means higher pH (>7). Note: significant interactions within and between factors are presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0097327#pone-0097327-t002" target="_blank">Table 2</a>.</p

The percentage distribution of each metal fraction in reduced condition in paddy soil samples in Zhangjiagang County.

<p>L means lower pH (<6), M means moderate pH (6–7), H means higher pH (>7). Note: significant interactions within and between factors are presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0097327#pone-0097327-t002" target="_blank">Table 2</a>.</p

Soil chemical properties of rice paddies in Zhangjiagang County, Jiangsu.

<p>Soil chemical properties of rice paddies in Zhangjiagang County, Jiangsu.</p

Correlation between the percentage distribution of cadmium in oxidized and reduced paddy soil samples in Zhangjiagang County.

<p>*, and ** denote the significant correlation at <i>p</i>≤0.05 and 0.01, respectively.</p