Sensitivity Analysis in Watershed Model Using SUFI-2 Algorithm

Abstract

The idea of watershed modeling is embedded in the interrelationships of geospatial and hydro-meteorological data and represented by mathematical abstractions. The behavior of each process is controlled by its attributes as well as by its interaction with other processes active in the catchment. Sensitivity analysis is an integral part of model development and involves analytical examination of input parameters to aid in model validation and provide guidance for future research. The Soil Water Assessment Tool (SWAT) model is utilized in the study for the simulation of the daily streamflow. Sensitivities of 21 input parameters have been analyzed using the SUFI-2 algorithm in SWAT Calibration Uncertainties Program (SWAT-CUP). For Langat River Basin, five SWAT input parameters show the most sensitive for both of the local and global sensitivity procedures, including of CN2.mgt, GW-Delay.gw, SLOPE.hru, SOL-AWC.sol and SOL-K.sol.