Gerlie S. Tolentino, Rafael J. Padre, Maria S Ramac, Pomy A. Viloria
The study determined the soil infiltration rate of crop production area of Kalinga State University, Tabuk City, Kalinga. Field testing at three different locations of the production area was performed using double ring infiltrometer having a diameter of 24 in and 12 in for the outer ring and inner ring respectively. The soil was characterize as clayey. Three infiltration models: Hortons, Kostiakov and Philips were used to simulate infiltration rates and compared with actual field measurements. Result showed that the infiltration rate models in KSU were i=239.5t^0.072,i=S〖383.7t〗^(-1/2)-137.5t and i=0.9525t+51.58(1-e^1.3423t) and for Philips, Lewis Kostiakov and Hortons. Across models, statistical analysis showed that, the model and observed values having an NSE of 0.59, 0.63 and 0.73 for Philip, Lewis Kostiakov and Hortons models. It demonstrated that the models generated is in agreement with the actual field experiments and can be used for characterizing soil infiltration rate.
Keywords: infiltration rate, crop production, infiltrometer, mathematical models, Kalinga State University