三峡水库消落带植被重建途径及其固土护岸效应

Revegetation and Its Effects on Soil Reinforcement in the Riparian Zone of Three-Gorge Reservoir

三峡水库蓄水运行后将出现一个落差达30m的消落带,由于库水涨落和水文地质条件改变,导致其植被破坏,土壤裸露,在降水、库水位周期性地涨落和波浪的作用下,土壤侵蚀强烈,如何重建消落带植被成为广泛关注的热点问题。通过系统总结三峡水库消落带植被重建的科研实践及经验,提出了消落带植被重建的基本思路和途径,并利用侵蚀针定位观测方法,对比分析了不同植被重建途径下的固土护岸效应。结果表明,人工种植草地和自然恢复草地较其对照分别减少了土壤侵蚀74%和55%,显示出极显著的控制土壤侵蚀的效应。而表层土壤受人为扰动强烈的传统耕作耕地土壤侵蚀强度相较于对照高11%。

Impoundment of the Three-gorge Reservoir （TGR） has formed 349 km^2 riparian zones with a 30 m annual water level fluctuating between 145 m and 175 m. Severe soil erosion has taken place within riparian landscape as the results of overlaid hydrological alternations, vegetation replacement and soil physic-chemical changes. How to restore the vegetation becomes a regional hot spot issue. Through the system summary on the scientific research practices and experiences of the vegetation reconstruction in Three-gorge Reservoir, the vegetation reconstruction basic strategy and ways are proposed in this study. Meanwhile, the soil erosion of different vegetation reconstruction was observed by erosion pins. The results show that the planted grass can reduce the soil erosion by 74%, followed by 55% in the natural grassland. The soil erosion intensity of tra- ditional farmland is 11% higher than the control because of the intensive artificial disturbance in surface soil.