Study on the susceptibility of debris flow disasters in southeast Tibet based on the information content model and random forest model

Abstract

Linzhi, in southeast of the Tibetan Plateau, has high mountain and gorge terrain. Recently, with rapid changes in climate and fast development of engineering construction in Tibet, the fragile ecological environment in Linzhi has been further damaged, resulting in a sharp increase in debris flow disasters in the region. This poses a serious threat to local social and economic development and safety of lives and property. We divided the study area into multiple watershed units, and explored the reliability of the information content model (ICM), random forest model (RF), and their coupled model (ICM-RF) in the evaluation of debris flow disaster susceptibility. Through remote sensing interpretation, field investigations, and data collection, data on debris flow disasters and evaluation indicators in the study area were obtained. Using multicollinearity analysis, 16 evaluation indicators were selected from 7 major categories including topography, geological conditions, meteorological and hydrological conditions, ecological environment conditions, human engineering activities, seismic activities, and watershed characteristics; a debris flow disaster susceptibility evaluation index system was constructed. Prediction performance of the three models was tested using ROC curves. ICM-RF model had better prediction performance than single models, indicating its superiority for predicting debris flow disaster susceptibility.