Abstract: Study on risk assessment of collapse gully erosion, a special type of soil erosion in South China, is rare. The feasibility of assessing the risk of collapse gully erosion in regional scale is explored in this paper with Jiangxi Province as study area. Risk assessment indexes are selected through relevant factor analysis, and the occurrence risk of collapse gully is calculated by bivariate statistical analysis of entropy information value, and the hazardous risk of collapse gully is estimated by using expert scoring method. By superposing the occurrence risk and the hazardous risk, the risk of collapsing gully erosion is obtained. Results unveil that the occurrence risk of collapse gully is higher in the south and west of Jiangxi Province, but relatively low in the eastern, northern and central part of the province. The hazardous risk of collapse gully in Jiangxi Province is low in general, but is relatively high in the central part yet in fragmented distribution. Superposing occurrence risk and hazardous risk reveals that medium risk takes up a major portion of collapse gully erosion in Jiangxi Province, which accounts for more than 63% of the total area of the province; high risk and above-high risk mainly distributes in the central part stretching in the direction from northeast to southwest of the province.

Key words: collapse gully erosion, risk assessment, bivariate statistical analysis, entropy information, Jiangxi Province