A study on soil chemical and physical properties of oxisols as indicator to predict shallow slope failure

Abstract

Landslides or slope failure has slowly become a major concern in Malaysia due to the rapid development of rural areas. Despite advances in science and technology, these events continue to result in human suffering, millions in property losses and environment degradation. The aim of this research was to find the indicator to predict shallow slope failure by studying the soil chemical and physical properties of oxisols. The comparison between the contain of the properties between stable slope and failure slope was discussed and analyzed with an observation and experiments from two different sites, which are at proposed highway KM13, Teluk Kemang, Port Dickson, Negeri Sembilan and alongside PLUS North- South highway road (from KM 420.0 to KM 445.5). The research discussed about the data interpretation and on how soil chemical and physical properties are related to the slope failure. From the outcome of the research and understanding of the relationship between soil chemical and physical properties and soil, the indicator of shallow slope failure which was based on the soil chemical properties found was used in measuring the slope hazardous level. From the data analysis, it is concluded overall that soil chemical and physical properties in stable slope contained more heavy metal, micronutrients, total nitrogen content, total organic carbon, available phosphorus and exchangeable cation concentration content for at least half of value content in failure slope. But unlikely in the stable slope, the content of cation exchange capacity (CEC) is high in failure slope. For soil pH, the values showed not much different between the stable and failure slope. In additional, it is also concluded that soil texture, clay contents, soil pH value, CEC, organic carbon contents, nitrogen contents and phosphorus content are those important elements in soil that could make the soil structure strong or weak. The elements contributed to each other as binding agents which will affect the strong soil structure. Soil pH values, CEC value and soil texture volume contents are the major factors of the shallow slope failure, as their characteristics affect the binding force of other elements. Thus, hopefully the areas which have a potential of slope failures occurring will be recognized and identified, in order to make sure the mass movement can be avoided and to help the developers and other parties involved in developing hillsides to find the better solution in order to prevent the landslides from happen again.