Abstract:
The gully debris flow caused by shallow landslides is characterized by the strong suddenness and great destructiveness, which often causes casualties and economic losses.The most effective way to reduce the loss caused by debris flow is to find and identify the potential points of geological disasters as soon as possible.Taking the gully debris flow induced by shallow landslide in Fujian Province as the research object, the longitudinal slope of the gully bed(J),the drainage area(A) and the topographic comprehensive value(T) are selected as the identification factors of gully debris flow.Based on the existing early warning methods, by analyzing the topographic characteristics of gully debris flow, an index parameter model for rapid identification of gully debris flow induced by shallow landslide is proposed, and the accuracy is evaluated by debris flow-prone valley in many areas.The results show that the model identified results are consistent with the actual situation, the accuracy rate is more than 89%.When the watershed meets the conditions of A≥0.03 km2,J≤0.42,and T≥0.28,the landslide material can easily lead to the occurrence of gully debris flow.The data required by the proposed empirical model are easy-measured topographic parameters, and the model can easily and quickly identify the valley-type debris flow watershed induced by potential shallow landslides.The research can provide reference for debris flow warning and disaster prevention and mitigation.