Table 2.
Descriptive statistics (mean and standard deviation) and the results of Tukey’s HSD test: (a) the biometric traits of B. pendula populations; (b) the soil properties from the Zn–Pb D, Coal mine D, Control L sites (significance level α = 0.05; a different lower-case letter means significant differences).
| (a) | ||||
|---|---|---|---|---|
| Biometric traits | Abbreviation | Zn–Pb D | Coal mine D | Control L |
| Number of leaves on the branch | LN | 247.56 ± 34.71a | 313.26 ± 38b | 412.26 ± 78.97c |
| Number of male catkin | MCN | 29.00 ± 8.41a | 57.70 ± 6.06b | 44.26 ± 7.64c |
| Number of female catkin | FCN | 18.63 ± 5.91a | 39.56 ± 5.04b | 50.03 ± 6.28c |
| Male:Female catkin ratio | MCN:FCN | 1.64 ± 0.55a | 1.46 ± 020a | 0.85 ± 0.13b |
| Male catkin length (cm) | MCL | 1.99 ± 0.19a | 2.93 ± 0.11b | 3.06 ± 0.14c |
| Female catkin length (cm) | FCL | 2.30 ± 0.11a | 2.53 ± 0.08b | 2.26 ± 0.40a |
| Number of mature female catkin | MtFCN | 253.63 ± 26.92a | 327.66 ± 17.50b | 474.28 ± 41.51c |
| Number of non-embrio seeds | N-ESN | 188.36 ± 19.72a | 70.31 ± 7.05b | 98.45 ± 8.02c |
| Number of full developed seeds | FDSN | 65.27 ± 12a | 257.35 ± 15.81b | 375.83 ± 42.66c |
| Mature female catkin length (cm) | MtFCL | 1.96 ± 0.16a | 3.51 ± 0.11b | 4.36 ± 0.13c |
| (b) | ||||
|---|---|---|---|---|
| Physicochemical soil parameters | Unit | Zn–Pb D | Coal mine D | Control L |
| pH (in KCl) | 6.47 ± 0.17a | 6.11 ± 0.12b | 6.76 ± 0.01c | |
| C organic carbon | g/kg | 227.04 ± 16.86a | 426.87 ± 12.70b | 182.50 ± 3.16c |
| N total | g/kg | 3.41 ± 0.24a | 6.14 ± 0.37b | 2.80 ± 0.12c |
| C to N ratio | 67.45 ± 0.85a | 69.54 ± 1.57b | 67.06 ± 3.34a | |
| Available K2O | mg/kg | 54.93 ± 10.46a | 145.95 ± 22.75b | 240.15 ± 23.35c |
| Available P2O5 | mg/kg | 7.10 ± 1.25a | 6.41 ± 0.74a | 43.55 ± 1.69b |
| Available MgO | mg/kg | 24.07 ± 8.21a | 10.41 ± 1.48b | 26.10 ± 0.48a |
| Exchangeable Na+ | mmol/kg | 0.65 ± 0.03a | 0.64 ± 0.03a | 1.81 ± 0.53b |
| Exchangeable K+ | mmol/kg | 2.05 ± 0.03a | 4.22 ± 0.52b | 7.06 ± 2.22c |
| Exchangeable Ca2+ | mmol/kg | 32.69 ± 0.11a | 47.75 ± 22.71b | 71.01 ± 0.07c |
| Exchangeable Mg2+ | mmol/kg | 0.25 ± 0.03a | 0.69 ± 0.17b | 24.02 ± 11.36c |
| Cd | mg/kg | 141.93 ± 3.91a | 17.65 ± 3.37b | 0.02 ± 0.01c |
| Pb | mg/kg | 14,566.35 ± 61.29a | 198.46 ± 1.43b | 284.09 ± 12.34c |
| Zn | mg/kg | 40,410.78 ± 151.21a | 265.85 ± 5.08b | 46.05 ± 2.94c |