Figure 2

Effect of DWTR addition on the metals and As concentrations in lake water under different conditions.
Mean values of concentrations measured at the 10th, 20th, and 30th d (n = 6) are presented. *And **represent significant differences at p < 0.05 and 0.01, respectively, for the metals and As concentrations in lake water with and without DWTR addition. CMC represents Criteria Maximum Concentration; CCC represents Criterion Continuous Concentration; U represents National Recommended Water Quality Criteria for freshwater in USA37; C represents Surface Water Quality Standard Class III used in China38; and Acute and chronic represent acute and chronic toxicity.