Selected physical and chemical properties of the raw materials used for the pot experimenta.
| Properties | Units | Soil | Compost | Biochar | Humic acid |
|---|---|---|---|---|---|
| pH | — | 7.92 ± 0.02 | 8.38 ± 0.03 | 8.13 ± 0.02 | 5.68 ± 0.03 |
| EC | μS cm−1 | 331 ± 12 | 920 ± 12 | 225 ± 10 | 342 ± 9 |
| Cd | mg kg−1 | 4.19 ± 0.05 | ND | ND | ND |
| As | mg kg−1 | 24.7 ± 0.54 | 3.67 ± 0.16 | 2.88 ± 0.11 | 3.07 ± 0.11 |
| Cr | mg kg−1 | 41.7 ± 0.32 | 16.60 ± 0.81 | 7.25 ± 0.56 | 26.88 ± 0.52 |
| Fe | mg kg−1 | 20 861 ± 659 | 3767 ± 30 | 932 ± 19 | 2779 ± 42 |
| Pb | mg kg−1 | 388 ± 4.3 | 11.45 ± 0.34 | 13.29 ± 0.84 | 18.85 ± 0.32 |
| Zn | mg kg−1 | 243 ± 5.23 | 37.07 ± 1.53 | 15.61 ± 0.51 | 12.95 ± 0.28 |
| Cu | mg kg−1 | 196 ± 1.27 | 12.20 ± 0.57 | 5.50 ± 0.32 | 13.12 ± 0.11 |
a
ND = below the limit of detection.