Most comprehensive hydrologic models divide the soil profile into multiple layers, and allow for percolation from one soil layer to the next and percolation from the bottom soil layer past the soil profile (as recharge to the shallow aquifer).
(Most comprehensive hydrologic models; divide; the soil profile; into multiple layers) (Most comprehensive hydrologic models; allow; for percolation)
Most comprehensive hydrologic models Most comprehensive hydrologic models
divide allow
the soil profile into multiple layers
for percolation