Research Article

Impact of Direct Soil Moisture and Revised Soil Moisture Index Methods on Hydrologic Predictions in an Arid Climate

Table 2

Sensitivity ranking of parameters for SMI and SMCII methods derived by SUFI-2 algorithm.

ParameterSensitivity rank
SMI SMCII

Effective hydraulic conductivity of main channel11
Base flow alpha factor2
SCS runoff curve number for mixing grassland and shrub land based on SMI/SMCII24
Manning coefficient for channel311
SCS runoff curve number for shrub land based on SMI/SMCII43
Surface runoff lag coefficient57
Maximum canopy index for mixing grassland shrub-land for SMI/maximum canopy index for SMCII610
Threshold depth of water in the shallow aquifer required for return flow to occur78
Reach of evaporation coefficient8
Threshold depth of water in the shallow for percolation to the deep aquifer for SMI/groundwater recharge to deep aquifer for SMCII912
Plant evaporation compensation factor10
Soil available water capacity115
Soil conductivity129
Deep aquifer percolation fraction13
Soil evaporation compensation factor146