Study of the Relationship between the Landslide and Precipitation in Zhejiang, Fujian and Guangdong Provence

The spatial and temporal distribution of landslide in Zhejiang, Fujian and Guangdong Provence is analyzed based on statistic data of landslide hazards and precipitation, and the relationship between landslide hazards and typhoon rainfall is considered. The spatial distribution of landslide hazards is uneven. Landslide in Guangdong Provence concentrates in the north-west and north of the mountain areas, it distributes in the central mountain areas in Fujian Provence while much more widely distributes in Zhejiang Provence, except for the Yangtze River Basin. Landslide occurs more frequently in Rainy season in summer. About 28% of all landslide hazards take place in July. Besides, It obviously ranges annually. According to statistics, there is an important factor that more than 75% landslide hazards occurr with medium precipitation during that day, and the accumulated 2-day-average precipitation before hazards is about 107.76 mm. The research offers a critical rainfall threshold for warning landslide hazards.