Table 12 Slopes* and estimated erosion in the northern catchment of Lake Tana
 Slope gradient | Entire catchment ha (%) and Soil loss tons (%) | Moderate erosion cells ha (%) and Soil loss tons (%) | High erosion cells ha (%) and Soil loss tons (%) | Extreme erosion cells ha (%)&Soil loss tons (%) |
|---|---|---|---|---|
Gentle slopes (0-3Ëš) | 35,030 (12.0) and 60,379 (3.6) | 2837 (8.4)& 2610 (0.4) | 879 (4.5) and 35,043 (19.4) | 210 (4.1) and 12,069 (1.5) |
Strong slopes (3-10Ëš) | 157,754 (54.0) and 581,022 (34.1) | 9144 (26.9) and 121,269 (20.6) | 6525 (33.3) and 48,601 (26.9) | 1443 (28.0) and 322,975 (41.5) |
Moderately steep (10-20Ëš) | 66,533 (22.8) and 548,350 (32.2) | 10,210 (30.1) and 183,917 (31.2) | 7356 (37.6) and 57,774 (32.0) | 1650 (32.0) and 261,493 (33.6) |
Steep slopes (20-45Ëš) | 32,573 (11.1) and 502,227 (29.5) | 11,634 (34.3) and 277,685 (47.2) | 4789 (24.5) and 39,201 (21.7) | 1823 (35.3) and 176,355 (22.6) |
Very steep (> 45˚) | 328 (0.1) and 9186 (0.6) | 133 (0.5) and 3085 (0.5) | 27 (0.1) and 56 (0.1) | 35 (0.7) and 6045 (0.8) |