Water Contamination and its Impact on Vegetable Production in the Rimac River, Peru - Agriculture in Urban Planning - page 118

P indicates statistical differences between sites ( significant, highly significant) and lower-case
caption indicates differences across sites.
Source: Contamination value in soils (C values) were taken from Chen (1992), Wang et al (1994)
and Chen et al (1996).
Figure 7.7 Total heavy metals in soils. Vertical lines represent the
standard error of the mean