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Relationships of the value of h 50 to RMSE and TET for each Case. (a) Case1; (b) Case 2; (c) Case 3; (d) Case 4.
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We examined the influence of input soil hydraulic parameters on HYDRUS-1D simulations of evapotranspiration and volumetric water contents (VWCs) in the unsaturated zone of a sugarcane field on the island of Miyakojima, Japan. We first optimized the parameters for root water uptake and examined the influence of soil hydraulic parameters (water reten...
Contexts in source publication
Context 1
... simulations run to optimize h 50 ( Figure 5) show that total evapotranspiration (TET) increased with increasing h 50 for all four cases considered. The optimal h 50 (smallest RMSE) was 600 cm for Case 1, 400 cm for Case 2, 300 cm for Case 3 and 700 cm for Case 4. For each of the four cases, the TET estimated with the optimized h 50 was almost the same as the measured TET (204.5 mm). ...
Context 2
... optimal h 50 (smallest RMSE) was 600 cm for Case 1, 400 cm for Case 2, 300 cm for Case 3 and 700 cm for Case 4. For each of the four cases, the TET estimated with the optimized h 50 was almost the same as the measured TET (204.5 mm). The simulation results for the pairs of cases with the same retention curve (Cases 1 and 4, Cases 2 and 3) were similar (compare Figures 5 and 6). The suction required to deplete VWCs during normal growth has been reported to be about 1000 cm [30]; therefore, we considered that Case 1 (600 cm) and Case 4 (700 cm) provided the more realistic values of h 50 for application in HYDRUS-1D, even though the RMSEs of Cases 2 and 3 were lower. ...
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Citations
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