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Table 2 Showing frequency ration and fuzzy membership values for different attributes

From: Landslide hazard zonation mapping using frequency ratio and fuzzy logic approach, a case study of Lachung Valley, Sikkim

Factors & attributes Landslide grid% Total area grid% Frequency ratio Membership function
Geology     
Quartzite/Garnet Schist 11.00% 5.40% 2.02 0.181
Permafrost 0.00% 13.50% 0 0
Migmatite/Biotite gneiss 89.00% 81.10% 1.1 0.098
Soil type     
Loam/sand 0.00% 0.54% 0 0
Rock/loam 9.50% 6.60% 1.44 0.129
Loam/rock 6.82% 20.70% 0.33 0.029
Permafrost 0.00% 4.31% 0 0
Sandy loam 68.18% 35.57% 1.92 0.172
Sandy/clay loam 14.09% 28.89% 0.49 0.044
Sandy/loam rock 1.36% 3.39% 0.40 0.035
Relative relief     
Very low (0–30 m) 6.25% 16.13% 0.39 0.0349
Low (30–60 m) 18.75% 37.24% 0.50 0.044
Moderate (60–100 m) 50.00% 40.97% 1.22 0.109
High (100–150 m) 18.75% 5.10% 3.68 0.329
Very high (>150 m) 6.25% 0.56% 11.16 1
Slope category     
0°-5° (Very low) 1.27% 2.03% 0.63 0.056
5°-15° (Low) 2.53% 11.70% 0.22 0.019
15°-25° (moderate) 8.86% 20.61% 0.43 0.038
25°-35° (Moderately high) 22.78% 27% 0.84 0.075
35°-45° (High) 45.57% 31.20% 1.46 0.130
>45° (Very high) 18.99% 7.46% 2.55 0.228
Aspect     
North 4.83% 0.8% 0.16 0.015
Northwest 10.18% 3% 0.294 0.026
West 14.57% 7% 0.48 0.043
Southwest 14.76% 14% 0.94 0.086
South 10.76% 40% 3.71 0.33
Southeast 16.10% 20% 1.24 0.11
East 16.8% 8.2% 0.48 0.044
Northeast 11.98% 7 0.58 0.05
Flat 0.0017% 0 0 0
Lineament buffer     
>200 m 56.25% 61.23% 0.92 0.082
0 – 50 m 15.00% 10.39% 1.44 0.129
50 – 100 m 7.50% 10.56% 0.71 0.063
100 m – 150 m 6.25% 9.42% 0.66 0.059
150 m – 200 m 15.00% 8.40% 1.79 0.160
Drainage buffer     
>200 m 43.75% 78.31% 0.56 0.050
0 – 50 m 18.75% 5.41% 3.46 0.31
50 – 100 m 10.00% 5.84% 1.71 0.153
100 m – 150 m 8.75% 5.12% 1.7 0.152
150 m – 200 m 18.75% 5.30% 3.54 0.317
LULC Type     
Fallow/Barren Land 53.75% 26.36% 2.04 0.182
Sparse Vegetation 38.25% 30% 1.27 0.113
Dense Vegetation 8% 41.40% 0.19 .017
Settlement 0 0.095% 0 0
Snow cover 0 1.65% 0 0