2013 Volume 7 Issue 4 Pages 91-96
Canopy interception (I) was measured using artificial Christmas trees that were set on three trays under natural rainfall. Tree heights were 65 cm, 110 cm and 240 cm, with two of the higher stands thinned after three months. Gross rainfall (PG) and water storage on a single tree of 65 cm high and 240 cm were measured, which enabled calculation of I not only on a per rain event basis but also over shorter time periods. Canopy interception rate (I/PG) was comparable with that in the actual forest. The value of I/PG tended to increase with tree height, while it increased or decreased after thinning depending on the forest structure. Evaporation during rainfall (IR), during storm break time (ISbt) and after the cessation of rainfall (IAft) was calculated on a sub rain event basis at a resolution of 5 minutes. A sub rain event was defined when rainfall broke for more than 20 minutes during the rain event. Among the three evaporation components, IR constituted nearly all of the total I, with ISbt close to zero and only a small contribution from IAft. The model forest appears useful for studying the mechanisms of I that are unexplainable using conventional approaches.