Modelling rainfall interception by vegetation of variable density using anadapted analytical model. Part 1. Model description

The revised analytical model to predict rainfall interception by sparse can opies (Journal of Hydrology 170 (1995) 79) is further modified to improve t he description of evaporation from wet vegetation whose canopy characterist ics vary in time (e.g. agricultural crops, deciduous forest, fast-growing p lantation forest, effects of storms, pests or logging, etc.). The main adju stments proposed are based on the following assumptions: (1) the canopy cap acity is linearly related to leaf area index; (2) the evaporation rate from a saturated canopy can be expressed as an exponential function of leaf are a index: and (3) evaporation from stems during the storms may be treated in a similar manner as that from the canopy. The comparative performance of t he revised and the presently proposed version of the analytical model in pr edicting interception by a mixed cropping system in West Java, Indonesia is discussed in a companion paper (Part 2). (C) 2001 Elsevier Science B.V. Al l rights reserved.