Physical characteristics of soils in the landslide areas of Cadac-an Watershed in Leyte, Philippines


Author(s): Jorge P. Cabelin1* and Beatriz C. Jadina2

Abstract

Landslides have become very frequent in Leyte which justifies the need for soil assessment and characterization of the landslide-prone areas in the province. This study assessed the physical characteristics of soils from the landslide areas in Cadac-an watershed in Leyte, Philippines. Landslide cuts located in the central highlands of Cadac-an watershed were used as representative profiles in this study. These were examined, characterized and sampled for the analyses of soil physical properties which include particle size distribution (Pipette method), bulk density (Paraffin-clod method), particle density (Pycnometer method), porosity, total soil wet density, water holding capacity and field capacity (Gravimetric method), saturated hydraulic conductivity (Constant head method), liquid limit and plastic index. Generally, soils from the landslide areas in Cadac-an watershed had a sandy loam to clay loam to clayey texture, low bulk density, low particle density, high porosity, moderate total soil wet density, moderate to high water holding capacity, low to moderate field capacity, moderately high to high saturated hydraulic conductivity, moderate liquid limit and low plastic index. Based on the above characteristics, the soils are susceptible to landslide occurrence thus it is highly recommended to conduct constant assessment and monitoring the area.

Keywords: landslides, soil physical characteristics, watershed, Leyte, Philippines