Assessment of soil reinforcement by Diospyros lotus roots using RDR ‎and RDDI indexes

The establishment and development of fast-growing trees with effective root systems and avoidance of deforestation are effective ways for slope stability and to reduce landslides. Soil reinforcement and reduction of erosion by tree root systems are influenced by physiological and ecological characteristics of roots. In this research, root reinforcement of Diospyros lotus, one of dominant species in the forests of northern Iran, was investigated by reinforced soil sampling and laboratory testing. Based on the results, shear strength of reinforced soil is related to two factors of root density and diameter. Evaluating test results by RDR and RDDI indexes showed that soil cohesion and shear strength of reinforced soil by Diospyros lotus roots increased by 207 and 350 percent respectively compared to unreinforced soil and this process has an effective role in Soil reinforcement and massive erosion control, especially in shallow landslides.