Transpiration from a Taro Leaf and the Moisture Availability of the Leaf Surface

Characteristics of the transpiration from a taro leaf is studied based on a field experiment. The transpiration from a single leaf was measured by a weighing procedure. The bulk transfer coefficient of the transpiration (Cs) determined using surface saturation specific humidity was found to have a constant value during the daytime within a single day, but to decrease as the plant life approaches to an end. The moisture availability defined as the ratio Cs to the coefficient for the sufficiently wet leaf surface was found to be about 0.7 in the daytime and near 0 in the nighttime.