Table 1 Contents of HMs and background values in topsoil of Sichuan (mg kg−1).
Element | As | Ba | Co | Cr | Cu | Mn | Ni | Pb | Zn | V |
|---|---|---|---|---|---|---|---|---|---|---|
Mean | 11.2 | 586.8 | 20.2 | 124.7 | 37.8 | 661.5 | 34.9 | 28.4 | 102.2 | 96.6 |
Minimum | 3.0 | 2926.0 | 7.4 | 72.0 | 16.7 | 71.6 | 16.7 | 16.6 | 40.0 | 42.8 |
Maximum | 30.0 | 873.4 | 93.9 | 252.0 | 369.9 | 1356.9 | 49.6 | 60.0 | 320.2 | 155.5 |
Median | 10.1 | 572.5 | 17.1 | 119.3 | 33.2 | 663.3 | 35.4 | 27.0 | 87.4 | 97.4 |
Standard deviation | 4.2 | 110.9 | 12.5 | 28.9 | 34.6 | 168.6 | 5.7 | 7.1 | 39.0 | 15.8 |
Coefficient of variation (%) | 37.6 | 18.9 | 62.0 | 23.2 | 91.6 | 25.5 | 16.2 | 24.9 | 38.2 | 16.4 |
Kurtosis | 4.5 | − 0.1 | 23.3 | 3.1 | 85.1 | 5.1 | 1.5 | 5.3 | 15.5 | 2.9 |
Skewness | 1.7 | 0.1 | 4.5 | 1.3 | 8.9 | 0.8 | − 0.8 | 1.9 | 3.4 | − 0.2 |
Reference value41 | 10.4 | 474.0 | 17.6 | 79.0 | 31.1 | 657.0 | 32.6 | 30.9 | 86.5 | 96.0 |
