Study on Correlation of Electrical Conductivity and Potential Large-scale Landslide in Taiwan

Chieh-Hsuan WENG, Yuan-Jung TSAI, Chjeng-Lun SHIEH and Tomohiro EGUSA

In this study, a total of 415 water samples were taken in southern and eastern Taiwan. The concentration of inorganic ions is detected using ion chromatography with an electricity conductivity meter to detect the electricity conductivity in water samples. In terms of time difference, the electricity conductivity of dry season is larger than wet season, the electricity conductivity value is about 300 ¼S/m, as electricity conductivity is affected by rainfall. For spatial difference, out of four study zones, the Kaoping watershed has highest value and coastal area in Taitung has lowest value. In Kaoping watershed, the difference of electricity conductivity value is about 200 ¼S/m. For the relationship between landslide rate and electricity conductivity, the potential landslide rate is calculated by dividing the sub-watershed area into large-scale potential landslide area, using the measurement points at downstream of the sub-watershed to represent the sub-watershed. It can regress a straight line, which R2=0.59. If the landslide rate is high, the electricity conductivity will be high. For analysis of electricity conductivity of stream, the electricity conductivity of stream is affected by inrush water from the potential landslide. When the measurement points are close to the inrush water, electricity conductivity will raise, on the contrary, when the measurement point is further from inrush water, the electricity conductivity will decrease. Above all, it can handle the relationship between landslide and electricity conductivity and hope to establish the warning system of the large-scale landslide, to fight for more time to respond to large-scale landslides.

2018/1 110-116