DEVELOPMENT OF NON-DESTRUCTIVE ROOT STRENGTH MODELS FOR PIONEER PLANTS OF EARTHQUAKE LANDSLIDE AREAS IN TAIWAN

摘要

Due to mechanical reinforcement and the frictional force at roots-soil binding, plant roots may restrain the occurrence of shallow landslides for slope lands. Pioneer tree species can also reduce runoff and soil erosion, are thus useful practical ecological materials for landslide control and erosion control. In this study, two important pioneer plant species - Formosan alder (Alnus formosana Makino) and Roxburgh sumac (Rhus chinensis Mill. Var. roxburghi i(DC.) Rehd.) - were selected at landslide areas undergoing vegetation treatments for soil and water conservation. In order to obtain the root strength model for the factors affecting pulling resistance and root tensile strength, experimental materials were tested and the data were analyzed using regression analysis. The relationship between maximum pulling resistance (Pr), basal diameter (D), and plant height (h) were found to be Pr = 3.504e~(0.247D) and Pr = 0.89h + 0.57D + 0.047D~2. These models could be used to provide an index of slope stability and to quantify-the root-strength using nori-destructive methods.