To represent situations with shallow bedrock, we need to allow for the saturated zone to reach 0, but currently we are assuming a water potential of 0 at the bottom of the unsaturated zone, leading to upwards water movement if the bottom layer of the unsat zone gets dry enough, but obviously, this would not be possible in the absence of groundwater.
To represent situations with shallow bedrock, we need to allow for the saturated zone to reach 0, but currently we are assuming a water potential of 0 at the bottom of the unsaturated zone, leading to upwards water movement if the bottom layer of the unsat zone gets dry enough, but obviously, this would not be possible in the absence of groundwater.