Table 1.
The content of cadmium, lead, and chromium in the soil (mg kg−1 d.m.).
| Material | Petrol Dose (cm3 kg−1 d.m. of Soil) | Average | r | |||
|---|---|---|---|---|---|---|
| 0 | 2.5 | 5 | 10 | |||
| Cadmium (Cd) | ||||||
| Without amendments | 0.216 ab | 0.270 bc | 0.342 cd | 0.414 d | 0.311 A | 0.989 |
| Compost | 0.270 bc | 0.270 bc | 0.288 bc | 0.288 bc | 0.279 AB | 0.845 |
| Bentonite | 0.198 ab | 0.306 bcd | 0.306 bcd | 0.198 ab | 0.252 BC | −0.169 |
| CaO | 0.144 a | 0.216 ab | 0.216 ab | 0.306 bcd | 0.221 C | 0.966 |
| Average | 0.207 I | 0.266 II | 0.288 II | 0.302 II | 0.266 | 0.884 |
| LSDp≤0.01 for: | petrol dose—0.034, materials—0.034, interaction—0.069 | |||||
| Lead (Pb) | ||||||
| Without amendments | 15.95 a | 19.35 b | 23.48 d | 31.80 g | 22.64 A | 0.999 |
| Compost | 33.68 gh | 32.40 g | 22.55 cd | 17.13 a | 26.44 B | −0.959 |
| Bentonite | 34.40 hi | 33.65 gh | 32.08 g | 21.15 bc | 30.33 C | −0.941 |
| CaO | 15.95 a | 25.93 e | 28.88 f | 35.90 i | 26.66 B | 0.958 |
| Average | 25.00 I | 27.83 II | 26.74 III | 26.49 III | 26.52 | 0.280 |
| LSDp≤0.01 for: | petrol dose—0.56, materials—0.56, interaction—1.12 | |||||
| Chromium (Cr) | ||||||
| Without amendments | 13.00 g | 18.33 h | 8.97 f | 8.71 ef | 12.25 A | −0.635 |
| Compost | 6.89 d | 5.98 cd | 5.98 cd | 4.68 bc | 5.88 B | −0.970 |
| Bentonite | 7.15 de | 5.98 cd | 3.25 ab | 2.08 a | 4.62 C | −0.955 |
| CaO | 6.76 d | 6.37 d | 4.16 b | 3.90 b | 5.30 B | −0.898 |
| Average | 8.45 I | 9.17 II | 5.59 III | 4.84 IV | 7.01 | −0.864 |
| LSDp≤0.01 for: | petrol dose—0.49, materials—0.49, interaction—0.97 | |||||
r—correlation coefficient. Values with different letters are significantly different at p ≤ 0.01: I–IV for the petrol dose, A–C for the material amendments, and a–i for the interaction between the petrol dose and the material amendments (ANOVA, Tukey’s HSD test).