Evaluation of Infiltration Indices Based on Double Ring Infiltrometer

Infiltration into the soil is the key parameter for water availability to rootzone of the crop. Infiltration rate may be affected with respect to different soil and climatic conditions. Therefore, information of infiltration rate is important to evaluate crop water requirement and irrigation purposes. The present study used double ring infiltrometer to evaluate infiltration capacity for 10 locations in Kalyanpur block of Bihar. The infiltration rate was estimated by Green Ampt model, Philips model, Kostiakov model and Hortons model for all locations. The slope and intercept parameters were evaluated by regression analysis of the observed data. The performance of the all models was evaluated by correlation coefficient (r), root mean square error (RMSE), mean absolute error (MAE), Nash-Sutcliffe efficiency (NSE) and Wilmot Index (WI). The GreenAmpt model was superior at eight sites while Philip's and Kostiakov models at one site each. Horton's model performed poorly at all sites. Thus, the study showed that the GreenAmpt model may applicable for infiltration rate within Kalyanpur block of Bihar.