The Systems Hydrologique European – European Hydrological System (SHE) is a physically based distributed model and it provides a useful setup for understanding the importance of evaporation data and soil parameters.
In this study, single column hydrologic simulations have been carried out for examining the sensitivity of this model to pan evaporation data of the various stations as well as the increase in conductivity of the unsaturated zone. Furthermore, the reduction in the value of exponent appearing in the Averjanov’s formula and reduction in the values of moisture content at wilting point and residual water content has been studied for a single grid of 2 km X 2 km size of the Narmada river.
It is observed that the simulated runoff and actual evapotranspiration are somewhat sensitive to the choice of various pan evaporation measurements stations. However, depth to groundwater table does not show any significant variations when the pan evaporation data of the different stations are used.
Increase in the value of conductivity of unsaturated zone leads to increase in actual evapotranspiration and decrease in runoff. Reduction in value of the exponent appearing in Averjanov’s formula, which is used in the SHE model decreases the simulated runoff and increases the actual evapotranspiration significantly.
Reduction in the values of water content of the soil also reduces runoff and significantly increases actual evapotranspiration. Also, it is observed that the groundwater table depletes considerably particularly during the dry periods for this case.
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