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FIG. 5. The impact of a different parameterization of water repellency on (A–E) the dynamics of water flow and repellency in the root zone and (F) the drainage rates out of the soil profile. All simulations use the parameter set with 
l2 = 0.1, 
min = 5° ± 1.5°, max = 90° ± 20°, 
crit = 0.015, t0 = 10 d, FK at 60 hPa. Only one of these parameters is modified for each simulation set: 0: max = min, 1: max = 70° ± 20°, 2: max = 90° ± 20°, 3: max = 130° ± 20°, 4: t0 = 20 d, 5: crit = 0.03, 6: FK at 20 hPa. Entire drying–rewetting cycle (vertical line denotes the start of the rewetting phase); the averages presented here are the arithmetic average of all nodes within the root zone (Fig. 1E): (A) Average volumetric water contents of the root zone. (B) Average matric heads of the root zone. (C) Average actual contact angles of the root zone. (D) Relative areas of the entire root zone where the actual contact angle >min. Rewetting phase only: (E) Average infiltration rate along a transect at the top of the root zone. The transect extends in 12.5-cm depth from 75- to 125-cm horizontal distance. The rate is in percentage of the precipitation rate; each symbol denotes 24 h. (F) Average drainage rate at the bottom of the soil profile in percentage of the precipitation rate; each symbol denotes 24 h.
