Table 4.
Pearson’s correlation coefficients among soil chemistries, soil Cd availability, and Cd concentrations in plants.
| pH | OM | CEC | A-P | A-Cd | A-Ca | A-Na | |
|---|---|---|---|---|---|---|---|
| A: correlation matrix of six soils under 440 mg·kg−1 Si added treatments | |||||||
| shoot-Cd | −0.175 | 0.825 ** | 0.314 ** | 0.186 | 0.768 ** | 0.182 | −0.305 * |
| A-Cd | 0.170 | 0.775 ** | 0.708 ** | 0.299 ** | 1 | 0.473 ** | −0.132 |
| B: correlation matrix of soil 3 under 0, 220, 440, 660 and 880 mg·kg−1 Si added dosages | |||||||
| shoot-Cd | −0.853 ** | −0.120 | −0.268 | −0.035 | 0.311 | −0.462 ** | −0.327 |
| A-Cd | −0.423 ** | 0.402 ** | 0.061 | 0.080 | 1 | 0.279 | −0.547 ** |
Note: shoot-Cd: Cd concentration of amaranth shoot; OM: organic matter; CEC: cation exchange capacity; A-P/Cd/Ca/Na: soil available P/Cd/Ca/Na. * p < 0.05; ** p < 0.01.