EVALUATION OF ROOT PROFILES AND ENGINEERING PROPERTIES OF PLANTS FOR SOIL REINFORCEMENT

The potential values and application of soil bioengineering techniques are crucial for the slope protection and ecological restoration. Knowledge related to the biological and engineering properties of plants is essential for the implementation of soil bioengineering techniques. Thus, four tropical species namely Leucaena leucocephala, Acacia mangium, Dillenia suffruticosa and Melastoma malabathricum were evaluated in terms of root profiles and root engineering properties. Leucaena leucocephala showed the highest root tensile strength followed by A. mangium, D. suffruticosa and M. malabathricum. Pull-out resistance was mostly affected by the root than the shoot profiles. Leaf area index (LAI) and root biomass were strongly correlated (R2 = 0.79), implying that the root biomass would be higher if the plant canopy was higher. Tree species, L. leucocephala and A. mangium, had deep rooting system and recommended for slope protection. Shrub species, M. malabathricum and D. suffruticosa had shallow root system and suggested for controlling soil erosion. Based on the overall engineering properties, L. leucocephala showed excellent performance through its root profiles and can be a potential plant for soil reinforcement. In conclusion, plant pull-out resistance, root tensile strength and type of roots can be used as important tools to identify plant performance for soil reinforcement. The results can be an aid to select potential slope plants for implementing soil bioengineering and slope protection techniques successfully.