Properties | Depth (cm) | Farmland soils (n = 300) | Control soils (n = 32) | |||||
---|---|---|---|---|---|---|---|---|
Range | Mean | SD | Median | Range | Mean | SD | ||
pH | 0–15 | 5.59–6.90 | 6.29 | 0.27 | 6.73 | 5.08–7.20 | 6.87 | 0.76 |
15–30 | 5.20–6.49 | 5.88 | 0.37 | 633 | 5.70–7.24 | 6.18 | 0.66 | |
OC (%) | 0–15 | 3.82–10.1 | 4.87 | 0.18 | 4.55 | 4.32–11.3 | 5.6 | 2.3 |
15–30 | 3.39–6.74 | 4.55 | 0.12 | 4.34 | 3.73–6.01 | 4.44 | 0.08 | |
OM (%) | 0–15 | 6.60–17.5 | 8.45 | 0.47 | 7.85 | 7.46–20.1 | 9.3 | 4.6 |
15–30 | 5.58–11.7 | 7.87 | 0.24 | 7.50 | 6.50–10.4 | 7.33 | 0.33 | |
Sand (%) | 0–15 | 47.0–84.4 | 72 | 15 | 78.3 | 75.5–84.4 | 76.7 | 4.6 |
15–30 | 44.5–82.4 | 71 | 13 | 75.5 | 66.7–79.6 | 75.0 | 5.9 | |
Silt (%) | 0–15 | 4.60–36 | 12.4 | 8.5 | 9.3 | 4.20–6.80 | 7.0 | 1.9 |
15–30 | 4.60–34.1 | 12.2 | 9.6 | 9.50 | 4.20–8.60 | 8.5 | 4.8 | |
Clay (%) | 0–15 | 10.8–21.5 | 15.6 | 6.9 | 15.8 | 10.6–17.9 | 14.3 | 3.9 |
15–30 | 10.6–22.0 | 16.6 | 6.3 | 17.3 | 16.2–24.7 | 17.5 | 6.1 |