Identification of Landslide-Prone Zones of Mandakini Valley (Central Himalaya) Post-Kedarnath Tragedy (2013)

By : Suman Das , Ashis Kumar Saha

Page No: 304-329

Abstract
Himalayan Terrain is highly susceptible to landslide events triggered by frequent earthquakes and heavy rainfall. In the recent past, cloud burst events are on rising, causing massive loss of life and property, mainly attributed to climate change and extensive anthropogenic activities in the mountain region. Despite the growing scientific and technological advances, it has been difficult to reduce the impact of natural hazards as experienced in case of 2013 Kedarnath Tragedy. The study aimed to identify the potential landslide hazard zone in Mandakini valley by utilizing different types of data including Survey of India toposheet, geological (lithological and structural) maps, IRS-1D, LISS IV multispectral and PAN satellite sensor data and field observations. The processing of multi-geo-datasets was carried out in a raster GIS environment. Data integration was performed using the ordinal scale (qualitative) relative weighting technique to give a Landslide Hazard Index value. The breaks through the equal interval in the landslide Hazard Index frequency curve used to delineate various landslide hazard zonation (LHZ), namely, very low, low, moderate, high and very high zone. Field data on landslides were employed to evaluate and validate the landslide hazard zonation map. It interpreted that the distribution of landslides is largely governed by a combination of geo-environmental conditions like proximity to the thrust zone, and barren or less-vegetated areas. The roles of climate, geology, geomorphology of the valley are also given attention to explain the reasons for the landslide occurrence in June 2013. The study also identifies the changes that occurred in LHZ before and after the disaster over the area. The results of the research may be used as an essential input to landslide disaster management.

Authors :
Suman Das : Department of Geography, Delhi School of Economics, University of Delhi, Delhi-100007.
Ashis Kumar Saha : University of Delhi, Delhi School of Economics, Department of Geography, Delhi, India.
 

DOI: https://doi.org/10.32381/ATNAGI.2020.40.02.8