EFFECTIVENESS OF COCONUT FIBER GEOTEXTILE AND VETIVER GRASS AS BIO-ENGINEERING TECHNIQUE IN MITIGATING SOIL EROSION ALONG BATO-BONTOC ROAD

Abstract

This study investigated the effectiveness and suitability of coconut coir fiber geotextile with different mesh sizes planted with Vetiver grass as a soil erosion control measure, conducted along Bato-Bontoc Road, Province of Southern Leyte, Philippines. The study was carried out by a 3x2 factor factorial experiment in Completely Randomized Design (CRD). Geotextiles with mesh sizes of 0.5x0.5, 1.0x1.0, 1.5x1.5 inches in planted and unplanted experimental plots, which has 7m by 1m dimensions, were considered in the experiment. To measure the decrease in topsoil, 12 erosion pins were forced drive into the soil in every experimental plot. No interaction was found between the geotextiles and the plant used. Based on the analysis of variance, there is a very highly significant difference in the soil erosion between planted and unplanted experimental plots. Vetiver grass is more effective in reinforcing soil and controlling up to 56% of the soil erosion than no grass at all. Geotextile with eye-opening sizes of 0.5x0.5, 1.0x1.0, and 1.5x1.5 inches can mitigate up to 65%, 49%, and 40% of the soil erosion, respectively. Thus, all sizes are effective in controlling soil erosion compared to the control setup and the 0.5x0.5-inch eye-opening size is the best among others.