Abstract

The water use of the introduced eucalypt trees has been much debated in southern India. The present study looks at the water loss of eucalypts by transpiration in an area in Kerala where the evaporative demands are relatively higher than in other zones. The results presented here have been obtained from the initial stages of a project with a much wider scope. The microclimatic data above the tree canopy has been measured on three sample days in October to December, 1990. Stomatal resistance was also measured hourly on all of these days. Using these measured parameters, transpiration was calculated using the Penman-Monteith equation. The cumulative transpiration loss during the sample days in October and November was approximately 5 mm, whereas it increased to approximately 8 mm in December. The reason for this increase is discussed