还是教程里的话最靠谱。The Saturated Only soil model is very useful for quickly defining a soil region that will always remain below the phreatic surface, but it should not be used for soils
that will at some point during the analysis become partially saturated. If this
happens, the model will continue to solve but you will be saying, in effect, that the
unsaturated zone can transmit the water at the same rate as for the saturated soil.
This will result in an over estimate of fl ow quantity and can result in an unrealistic
water table.