WETTING CHARACTERISTICS OF SOME TROPICAL TREE SPECIES

Abstract

Interception is a physical process, which represents a definite loss of rain-water,since most plants can absorb water only through their roots. 771e quantity lostdepends on how the canopy is wetted by the falling rain, and the amount of waterstored on the vegetation after the rain stops. Information on these points is needed inmodelling studies aimed at estimating the interception loss under varying climaticconditions. This study compared the welling characterisitics of Acacia decurren,Artocarpus heterophyllus, Eucalyptus microcorys, Hcdyotis confertiflora, Pinuscaribaca, Rhododendron zeylanicuni, Syzygiun! rotundifoliunt, and Tectono gram/is./1 rainfall simulator was used 10 generate three drop sizes. Maximum interceptionand interception loss for each species and for each drop size were measured on abranch representing a projected canopy area of one square metre. The resultsshowed that the interception loss depends on the species and not on the raindrop sizeand that it is inversely proportional to leafsize. Front the point ofview ofmaximizingthe catchment water yield, the species with larger leaves, such asjak and teak, whichgive the least interception losses, are more suitable Jhr planting in drier areas, whilespecies with smaller leaves are more suitablefor wetter areas.