Measurements of transpiration in four tropical rainforest types of north Queensland,Australia |
| |
Authors: | David McJannet Peter Fitch Mark Disher Jim Wallace |
| |
Affiliation: | 1. CSIRO Land and Water, 120 Meiers Rd, Indooroopilly, Queensland, Australia;2. CSIRO Land and Water, Clunies Ross St, Black Mountain, ACT, Australia;3. CSIRO Land and Water, Davies Laboratory, Townsville, Queensland, Australia |
| |
Abstract: | Transpiration of four different rainforest types in north Queensland, Australia, was determined using the heat pulse technique for periods ranging between 391 and 657 days. Despite the complexity of the natural rainforest systems being studied, the relationship between sample tree size and daily water use was found to be strong, thus providing a robust means by which to scale transpiration from individual trees to the entire forest stand. Transpiration was shown to be dependent on solar radiation and atmospheric demand for moisture with little evidence of limitation by soil moisture supply. Total stand transpiration was controlled by forest characteristics such as stem density, size distribution and sapwood area. Annual transpiration for each of the four sites ranged between 353 mm for cloud forest and 591 mm for montane rainforest. In comparison with the international literature, transpiration from Australian rainforests is low; the reasons for this could be related to a combination of differences in forest structure, climatic conditions, canopy wetness duration and tree physiology. Copyright © 2007 John Wiley & Sons, Ltd. |
| |
Keywords: | tropical rainforest transpiration sapwood area vapour pressure deficit solar radiation potential evapotranspiration |
|
|