| Category | θSlope range | Winter | Spring | Summer | Autumn | ||||
Area Km2 | % | Area Km2 | % | Area Km2 | % | Area Km2 | % | |||
1 | Significant degradation | θ < −0.035 | 18,647.1 | 2.6 | 12,351.3 | 1.7 | 4870.7 | 0.7 | 137,223.7 | 19.2 |
2 | Moderate degradation | −0.035 < θ > −0.025 | 13,575.9 | 1.9 | 12,441.0 | 1.7 | 5259.1 | 0.7 | 58,084.6 | 8.1 |
3 | Mild degradation | −0.025 < θ > −0.015 | 18,026.6 | 2.5 | 12,211.4 | 1.7 | 11,956.7 | 1.7 | 62,151.4 | 8.7 |
4 | No change | −0.015 < θ > 0.015 | 569,743.6 | 79.6 | 532,533.3 | 74.4 | 437,078.4 | 61.1 | 417,940.4 | 58.4 |
5 | Mild improvement | 0.015 < θ > 0.025 | 31,739.4 | 4.4 | 53,193.6 | 7.4 | 102,224.4 | 14.3 | 16,939.9 | 2.4 |
6 | Moderate improvement | 0.025 < θ > 0.035 | 33,787.9 | 4.7 | 44,542.9 | 6.2 | 73,276.1 | 10.2 | 13,880.8 | 1.9 |
7 | Significant improvement | θ > 0.03 | 30,303.3 | 4.2 | 48,550.3 | 6.8 | 81,158.4 | 11.3 | 9602.9 | 1.3 |
| Total |
| 715,823.8 | 100 | 715,823.8 | 100 | 715,823.8 | 100 | 715,823.8 | 100 |