The importance of canopy structure in controlling the interception loss of rainfall: Examples from a young and an old-growth Douglas-fir forest

The Gash model successfully predicted In for the young forest on a seasonal basis (3.29% error), but experienced larger errors (range = −91 to 36% error) for individual storms. The seasonal error and the error for individual storms improved when seasonal variations in canopy characteristics were incorporated in the model (seasonal error = 2.37%; individual storm error range = −12.0 to 21.7%). Therefore, short-term (seasonal) changes in phenology and long-term (decades to centuries) horizontal and vertical development of the forest canopy influence S, p, In and E¯/R¯ of Douglas-fir forests.