Abstract: Huanggang City is located in a low mountainous and hilly area subjected to frequent small-scale landslide disasters. Rainfall is a major external cause of such landslide disasters. Analyzing the contributions of influencing factors to the number of rainfall-induced landslides and the relation between landslide and rainfall is of vital significance for the disaster prevention and mitigation in Huanggang. According to observation data of 238 meteorological stations in Huanggang from 2011 to 2020 together with landslide disaster data, the regional distribution of rainfall-induced landslide in Huanggang was examined. The contribution rates of monthly average rainfall, engineering rock formation, and slope gradient to the number of rainfall-induced landslides were obtained, and on such basis, the rainfall-induced landslides in the area were classified as highly susceptible, moderately susceptible, and lowly susceptible. Moreover, the reference values of rainfall corresponding to three levels, namely, forecast, early warning, and alarm were given with daily average rainfall in critical period and daily average rainfall in previous period as the rainfall threshold judgment criteria. The research findings offer basic data and scientific basis for the prevention and control of regional landslide disasters.

Key words: rainfall-induced landslide, relation with rainfall, contribution rate, Huanggang, susceptible area