4. Geomorphic Diversity and Landslide Susceptibility: A Multi-criteria Evaluation Approach

The present study attempts to assess the role of basin morphometric parameters in slope instability using morphometric diversity (MD) model. Also try to find out the role of drainage parameters and relief parameters in slope failure using drainage diversity (DD) and relief diversity (RD) models respectively. For that total 14 morphometric data layers were considered. The relationship of each data layers with landslide susceptibility was judge using frequency ratio (FR) approach. Parameters like drainage density, drainage frequency, relative relief, drainage texture, junction frequency, infiltration number, ruggedness index, dissection index, elevation, slope, relief ratio and hypsometric integral were positively related with landslide potentiality while bifurcation ratio and drainage intensity negatively correlated with slope failure. The principal component analysis (PCA) based weight assign to each data layers of each model which multiplied with unidirectional reclassified data layers for each model using weighted linear combination (WLC) approach to prepare landslide susceptibility maps. The receiver operating characteristics curve showed that, the landslides prediction accuracy of the DD, RD and MD models was 71.4, 73.9 and 76.3% respectively. The FR plots of the aforesaid three models suggested that, the chance of landslide increases from very low to very high susceptibility zones.