The root anchorage ability of Salix alba var. tristis using a pull-out test
The vegetation materials may reduce soil erosion and runoff, create space for breeding and habitat and they are commonly used in river ecological engineering. Therefore, it is important to select the soil-bioengineering plant by taking its growth characteristics and the soil solidity of its root system as the major considerations. Because Salix alba var. tristis has a strong capability of keeping moisture, preventing drought and reducing wind, we selected it as a model species for soil bioengineering research and application in Beijing, China. In this study, we aimed to investigate the soil-reinforcing effects by Salix alba var. tristis. We performed a pull-out test on 4 year live stakes and measured their morphological characteristics. Our results showed that, the plant had a satisfactory root development after 4 years, and the pull-out resistive force had the strongest correlations with the morphological parameters of plant, such as height (R2 = 0.79, P < 0.001) and diameter at shoot base (R2 = 0.69, P < 0.001).
Key words: Salix alba var. tristis, uprooting resistance, live stakes, soil bioengineering.