Physical Properties of Soil and Its Correlation with River Bank Erosion and Soil Erodibility: Sungai Pusu Case Study

Riverbank erosion is a complex process where the extent of riverbank erosion is influenced by many factors including soil properties. In this study, soil samples were collected from different sections of riverbanks at Sungai Pusu. Several physical soil properties such as the median grain size, percentage of sand, silt and clay, plasticity index, and specific gravity were measured for each soil samples. Riverbank erosion rates were measured at the site periodically using erosion pin method. Linear regression was conducted to identify the correlation between the erosion rate and the physical soil properties using the Statistical Package for the Social Science (SPSS) software. It was found that the percentage of sand content had significantly influenced the erosion rate, while the other parameters showed weak correlation and no correlation with the erosion rate. Soil erodibility coefficient, kd, was calculated using empirical equation, and the value ranged between 0.0553 and 0.1023 cm3/N s. The erodibility of the soil samples can be categorized as “Moderately resistant” based on the τc versus kd plot produced by previous study.