Calibration of LEACHN model using LH-OAT sensitivity analysis

Abstract

LEACHN model is useful to describe the nitrogen transport and transformation in soil but requires many input parameters. A sensitivity analysis can help to sort out the sensitive ones among many input parameters. A global sensitivity analysis technique, Latin Hypercube One factor At a Time (LH-OAT) method, was applied to LEACHN model in this study. Only a few parameters were found to be sensitive compared to many input parameters of the model from the sensitivity analysis. Using the results from the sensitivity analysis, calibration and validation of LEACHN model for nitrate leaching was performed for the experimental results from pot experiments that consisted of six types with different soil depth in mini-lysimeters and different fertilizer additions. The results indicated that the use of LH-OAT method could help the facile field application of LEACHN model. Model fitting could be improved by adopting current values in yearly crop parameters in validation.