Two-component analysis of flow through macroporous soil

Subsurface hydrographs, obtained during rainfall simulation on Im by Im plo ts, were separated into macropore and micropore components by application o f a dual-porosity concept and mass balance analysis. The corresponding solu te concentrations in the two domains were also determined by mass balance a nalysis. Time-domain reflectometry was then used to estimate similar outflo w hydrographs and breakthrough curves at an upper depth in the A horizon of the soil profile. The results show that the macropores contributed from 6 to 54% of total subsurface flow and from 1 to 61% of total solute mass tran sported through the soil profile. (C) 2001 Silsoe Research.