Debris flow and landslide hazard mapping and risk analysis in China

This paper assesses the hazardousness, vulnerability and risk of debris flow and landslide in China and compiles maps with a scale of 1:6000000, based on Geographical Information System (GIS) technology, hazard regionalization map, socioeconomic data from 2000. Integrated hazardousness of debris flow and landslide is equivalent to the sum of debris flow hazardousness and landslide hazardousness. Vulnerability is assessed by employing a simplified assessment model. Risk is calculated by the following formula: Risk = Hazardousness x Vulnerability. The analysis results of assessment of hazardousness, vulnerability and risk show that there are extremely high risk regions of 104 km(2), high risk regions of 283008 km(2), moderate risk regions of 3161815 km(2), low risk regions of 3299604 km(2), and extremely low risk regions of 2681709 km(2). Exploitation activities should be prohibited in extremely high risk and high risk regions and restricted in moderate risk regions. The present study on risk analysis of debris flow and landslide not only sheds new light on the future work in this direction but also provides a scientific basis for disaster prevention and mitigation policy making.