Table 2.
Physicochemical characterization of rhizosphere and non-rhizosphere substrates from mine tailings and surrounding soil.
| Substrate parameters †,¶ | Substrates | ||||||
|---|---|---|---|---|---|---|---|
| Tambillos tailings | Huana tailings | Surrounding soil | Fresh tailings | ||||
| R | N-R | R | N-R | R | N-R | N-R | |
| Soil pH soil:H2O 1:1 | 7.89 ± 0.19 | 7.14 ± 1.0 | 7.95 ± 0.17 | 7.52 ± 1.46 | 8.35 ± 0.42 | 7.09 ± 0.69 | 7.69 ± 0.15 |
| EC (mS cm−1) | 2.6 ± 0.7↑ | 5.2 ± 0.5↑↑ | 3.5 ± 1.0↑ | 7.2 ± 2.1↑↑ | 0.3 ± 0.1 | 1.7 ± 0.2 | 4.3 ± 0.3↑↑ |
| CEC (meq 100 g−1) | 27.0 ± 8.9 | 8.7 ± 4.9 | 31.7 ± 6.8 | 6.7 ± 3.1 | 35.0 ± 11.4 | 14.7 ± 5.1 | 24. 3 ± 7.1 |
| DOC (mg L−1) | 42.5 ± 17.0 | 21.5 ± 6.0 | 25.0 ± 5.0 | 6.0 ± 2.5 | 98.0 ± 11.0 | 34.0 ± 10.5 | ND‡‡ |
| Soluble SO42− (g L−1) | 0.52 ± 0.2↑↑ | 2.97 ± 0.39 | 0.88 ± 0.49↑↑ | 1.73 ± 0.26 | 0.03 ± 0.01 | 0.32 ± 0.08 | 0.94 ± 0.28↑↑ |
| Texture (%) | |||||||
| < 2 µm | 12.8 ± 3.8 | 13.6 ± 10 | 23.1 ± 8.1 | 10.3 ± 5 | 15.4 ± 7.8 | 16.9 ± 6 | 24.9 ± 11.3 |
| 50–2 µm | 35.1 ± 4.6 | 43.6 ± 13 | 53.0 ± 8.4 | 36.5 ± 18 | 14.9 ± 15.1 | 22.2 ± 9 | 60.2 ± 23.7 |
| 200–50 µm | 52.2 ± 6.3 | 42.8 ± 19 | 23.9 ± 12.1 | 53.1 ± 21 | 69.8 ± 22.9 | 60.9 ± 11 | 16.0 ± 29.7 |
| Soil type | Loam | Loam | Silty loam | Sandy loam | Sandy loam | Sandy Loam | Silty loam |
R rhizosphere, N-R non-rhizosphere, EC electrical conductivity, CEC cation exchange capacity, DOC dissolved organic carbon.
†Values are given as mean and standard error (2–6 replicates).
¶↑ High, or ↑↑ very high, according to standard analytical soil parameters.
‡‡ND: not determined.