关键词: 三峡库区, 梯田稳定性, 分析与对策

Abstract: The key problem of the Three Gorges Project is the people resettlement in the reservoir area. Terracing on slopes is one of the important technical measure for solving it. The reservoir area has been seriously endangered by landslides and collapses in history. There are more than 510 landslides and collapses from 1982 to 1987 in Zigui county. It has been confirmed after field investigation in reoent years that the stability of terrace located on accumulation of landslides and collapses has been often imperiled by wriggling and sliding of them. Landslides and collapses are very strangely influenced by rainfall. Generally, if precipitation (daily or time) is more than 50 mm, shallow landslides occur frequently. According to our experimental results, the infiltration rate on terrace is 3 times than slope land, so terrace on accumulation causes slide to happen easily. The anti-weathering ability of the stone bank of terrace is another very important factor influencing the stability of terrace. We have evaluated the classification of purple rocks, which depends on the mineral composition, the chemical and physical behavior, the crack of rocks. Based on field investigation and experimental results, this paper has discussed the characteristics, property and present situation for 4 kinds of un-stable bank of terrace in detail;bank with the weathering purple rock, soil ridge of terrace, bank with the weathering crust of granite, cobble bank of terrace. The most important way is living hedge, that means to plant shrubs and grasses along or on the bank of terrace, which can stabilize the bank of terrace, prevent soil erosion and provide some products. The detail description has been given to species selection, experiment design and economic benefit.

Key words: the three gorges reservoir area, stability of terrace, analysis and measure