Tap root and lateral root systems of trees have long been recognized for enhancing slope stability by reinforcing soil strength. Among these, the lateral root system is particularly effective in preventing shallow landslides. In South Korea, where forest soils are relatively shallow, the role of tree roots in stabilizing slopes is becoming increasingly important. This study aimed to evaluate the root cohesion of four major tree species in South Korea: Pinus densiflora, Pinus koraiensis, Larix kaempferi, and Quercus mongolica. To achieve this, we investigated the spatial distribution of their lateral root systems using the profile wall method in an experimental forest at Kangwon National University. In addition, the relationship between root diameter and tensile strength was assessed in the laboratory using a universal testing machine. Based on the findings, root cohesion was estimated using the Wu model. For all species, the number of roots and root area ratio decreased with increasing soil depth, although the extent of decrease varied by tree species. A power-law regression model effectively described the relationship between root diameter and tensile strength in all species. The average root tensile strength was higher in Q. mongolica (22.2 MPa) and L. kaempferi (20.2 MPa) than in P. densiflora (15.9 MPa) and P. koraiensis (15.0 MPa). Root cohesion estimated using the Wu model was 1.5 to 5.1 times higher than that measured by the direct shear test. After applying a reduction coefficient, root cohesion estimated by the Wu model was highest in Q. mongolica (12.9 kPa), which exhibited the greatest root area ratio and tensile strength, followed by P. koraiensis (9.1 kPa), P. densiflora (9.0 kPa), and L. kaempferi (4.3 kPa). These results provide useful information for quantifying the role of tree roots in preventing shallow landslides and can support the establishment of forest disaster management strategies.
저자
Kidae Kim [ Department of Forestry and Environmental Systems, Kangwon National University ]
Mirae Han [ Department of Forestry and Environmental Systems, Kangwon National University ]
Inyoung Lee [ Department of Forestry and Environmental Systems, Kangwon National University ]
Sukwoo Kim [ Division of Forest Science, Kangwon National University ]
Corresponding Author
