Which is more hazardous: avalanche, landslide, or mudslide?

Gravity erosion is a dominant geomorphic process on the steep loess slopes. Here, we conducted rainfall simulation experiments to monitor occurrence and behavior of the mass failure on steep loess slopes. The results show that the quantity of soil loss caused by avalanche and landslide was much more than that caused by mudslide, and the avalanche was the most violent gravity erosion. As the slopes were eroded with five runs of rainfalls each at an amount of 48 mm, the total volume of avalanche, landslide, and mudslide were 150.9, 82.5, and 3.9 × 10 3 cm 3 /m, and their maximum individual amounts were 369.9, 177.6, and 24.6 × 10 3 cm 3 , respectively. The amount of avalanche, landslide, and mudslide accounted for 62, 36, and 2 % of the total gravity erosion in a rainfall experiment of the model test. Furthermore, the slope height and gradient had a remarkable impact on the erosion amount. When the slope height was increased from 1.0 to 1.5 m, the total amount of avalanche was increased by 22 %, and the maximum volume of individual avalanche was augmented by 165 %. When the slope gradient was increased from 70° to 80°, the total amount of landslide was enlarged by 52 %, and the maximum amount of individual avalanche was magnified by 65 %. As a result, avalanche and landslide, especially the former, played a crucial role of soil erosion on steep slope compacted by hand with loess. Copyright Springer Science+Business Media Dordrecht 2015