Landslides Triggered by the 2016 Heavy Rainfall Event in Sanming, Fujian Province: Distribution Pattern Analysis and Spatio-Temporal Susceptibility Assessment

Rainfall-induced landslides pose a significant threat to the lives and property of residents in southeast mountainous area. From 5 10 May 2016, Sanming City Fujian Province, China, experienced heavy rainfall event that caused massive landslides, leading loss life property. Using high-resolution satellite imagery, we created detailed inventory triggered by this event, which totaled 2665 across an area 3700 km2. The majority were small-scale, shallow elongated, with dominant distribution Xiaqu town. We analyzed correlations between landslide abundance topographic, geological hydro-meteorological factors. Our results indicated index is related gradient hillslope, distance from river total rainfall. density, i.e., LAD increases increase these influencing factors described exponential or linear relationship. Among all lithological types, Sinian mica schist quartz (Sn-s) found be most prone over 35% occurring just 10% Overall, lithology characteristics primarily control followed topography. To gain better understanding triggering conditions for conducted physically based spatio-temporal susceptibility assessment numerical simulations, using MAT.TRIGRS tool, show it can accurately reproduce temporal evolution instability process event. Although before 8 may have contributed decreased slope stability study area, short duration on believed primary factor occurrence landslides.