The county-level assessment on risk of collapses, landslides, and debris flows in Guangdong using GIS and remote sensing

Based on Excel and ArcGIS10.0 software package, this paper uses spatial overlay statistics and correlation analysis to study the risk of collapses, landslides, and debris flow hazards in every county of Guangdong, including their danger and vulnerability. The results are shown as follows; Firstly, terrain and precipitation are major factors in risk assessment of geological hazard in Guangdong. Within this, the maximum relative elevation is the restricting factor in danger degree of hazards. The major factor is from terrain to precipitation, when the maximum relative elevation is near 1200m. Secondly, high strong and short duration precipitation exerts more effect on the danger of hazards than average annual precipitation of long period and zonal. Thirdly, By analyzing the socio-economic data of every county, the study assess the vulnerability and risk degree of every county and proofs the major factor on the evaluation of hazards risk is the intensity of human activities.