Respective influence of vertical mountain differentiation on debris flow occurrence in the Upper Min River, China

Mingtao Ding,Guohui Yang,Tao Huang,Hao Zheng

doi:10.1038/s41598-020-68590-2

Abstract

The generation, formation, and development of debris flow are closely related to the vertical climate, vegetation, soil, lithology and topography of the mountain area. Taking in the upper reaches of Min River (the Upper Min River) as the study area, combined with GIS and RS technology, the Geo-detector (GEO) method was used to quantitatively analyze the respective influence of 9 factors on debris flow occurrence. We identify from a list of 5 variables that explain 53.92%% of the total variance. Maximum daily rainfall and slope are recognized as the primary driver (39.56%) of the spatiotemporal variability of debris flow activity. Interaction detector indicates that the interaction between the vertical differentiation factors of the mountainous areas in the study area is nonlinear enhancement. Risk detector shows that the debris flow accumulation area and propagation area in the Upper Min River are mainly distributed in the arid valleys of subtropical and warm temperate zones. The study results of this paper will enrich the scientific basis of prevention and reduction of debris flow hazards.

Highlights

Debris flows are a common type of geological disaster in mountainous areas[1,2], which often causes huge casualties and property losses[3,4]
The Upper Min River belong to the alpine and plateau alpine climatic zone[16], and, warm temperate zone, temperate zone, cold temperate zone, subrigid zone, frigid zone, ice-snow zone appear in order from the valley to the ridge
The Upper Min River was used as the study area, and vertical zones, annual average temperature, maximum daily rainfall, sunshine hours, vegetation type, soil type, slope, aspect and lithology 9 factors representing the vertical differentiation characteristics of the mountain were selected

Summary

Introduction

Debris flows are a common type of geological disaster in mountainous areas[1,2], which often causes huge casualties and property losses[3,4]. The generation, formation, and development of debris flows are closely related to the vertical climate, vegetation, and soil conditions of a given mountainous area. There are multiple useful statistical tools that are widely recognized to compute this sort of correlation between factors and the predictive power of a variable These methods mainly include spatial autocorrelation test Moran’s I40, semivariogram[41], Ripley K42, hot spot detection Gi43, LISA44, SatScan[45], multivariate Logistic regression model[46,47]; spatial regression SAR/MAR/CAR4 8–50, GWR5 1, spatial Bayesian hierarchical model B HM52, etc. The factors of debris flow occurrence are spatial stratified heterogeneity, so there are limitations to applying the above methods to calculate the factors influence of vertical mountain differentiation on debris flow o ccurrence[53]

Methods

Results

Discussion

Conclusion