ESTIMATING GROUNDWATER RECHARGE USING A SURFACE WATERSHED MODEL - SENSITIVITY ANALYSES

The methodology used to estimate groundwater recharge using a surface watershed modelling approach was presented in a complementary paper. This paper describes the analyses carried out to investigate the sensitivity of the objective function and the recharge estimates to the parameters in HYDROLOG. The analyses were carried out in Axe Creek Catchment (sub-area 1 in the complementary paper) using NLFIT (an optimisation package) and sensitivity plots. The analyses were performed to investigate the ability of HYDROLOG to estimate recharge and to guide further improvements in the model. Based on the analyses, a detailed discussion of the parameters in HYDROLOG is presented and the important parameters highlighted. © 1990.