Vol17 No.11: 2652-2673
【Title】Landslide susceptibility assessment at Kathmandu Kyirong Highway Corridor in pre-quake, co-seismic and post-quake situations
【Author】Susmita DHAKAL1,2,3; CUI Peng1, 2, 4*; SU Li-jun1, 2, 4, 5; Olga MAVROULI6; ZOU Qiang1; ZHANG Jian-qiang1; Lalu PAUDEL7; Nirusha SHRESTHA7
【Addresses】1 Institute of Mountain Hazard and Environment, Chinese Academy of Sciences, Chengdu 610041, China; 2 University of Chinese Academy of Sciences, Beijing 100049, China; 3 Central Department of Environmental Science, Tribhuvan University, Kathmandu 44613, Nepal; 4 CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China; 5 China-Pakistan joint Research Center on Earth Sciences, Islamabad 45320, Pakistan; 6 Faculty of Geo-information Science and Earth Observation, University of Twente, 7500 AE, The Netherlands; 7 Central Department of Geology, Tribhuvan University, Kathmandu 44613, Nepal
【Corresponding author】CUI Peng
【Citation】DhakalS, Cui P, Su LJ, et al. (2020)Landslide susceptibility assessment at Kathmandu Kyirong Highway Corridor in pre-quake, co-seismic and post-quake situations. Journal of Mountain Science 17(11). https://doi.org/10.1007/s11629-020-6314-x
【Abstract】Kathmandu Kyirong Highway (KKH) is one of the most strategic Sino-Nepal highways. Low-cost mitigation measures are common in Nepalese highways, however, they are not even applied sufficiently to control slope instability since the major part of this highway falls still under the category of feeder road, and thus less resources are made available for its maintenance. It is subjected to frequent landslide events in an annual basis, especially during monsoon season. The Gorkha earthquake, 2015 further mobilized substantial hillslope materials and damaged the road in several locations. The aim of this research is to access the dynamic landslide susceptibility considering pre, co and post seismic mass failures. We mapped 5,349 multi-temporal landslides of 15 years (2004-2018), using high resolution satellite images and field data, and grouped them in aforementioned three time periods. Landslide susceptibility was assessed with the application of ‘certainty factor' (CF). Seventy percent landslides were used for susceptibility modelling and 30% for validation. The obtained results were evaluated by plotting ‘receiver operative characteristic' (ROC) curves. The CF performed well with the ‘area under curve' (AUC) 0.820, 0.875 and 0.817 for the success rates, and 0.809, 0.890 and 0.760 for the prediction rates for respective pre, co and post seismic landslide susceptibility. The accuracy for seismic landslide susceptibility was better than pre and post-quake ones. It might be because of the differences on completeness of the landslide inventory, which might have been possibly done better for the single event based co-seismic landslide mapping in comparison with multi-temporal inventories in pre and post-quake situations. The results obtained in this study provide insights on dynamic spatial probability of landslide occurrences in the changing condition of triggering agents. This work can be a good contribution to the methodologies for the evaluation of the dynamic landslide hazard and risk, which will further help to design the efficient mitigation measures along the mountain highways.
【Keywords】Dynamic landslide susceptibility; Sino-Nepal highway; Gorkha earthquake; Certainty factor