Diffusive Resistances at, and Transpiration Rates from Leaves in Situ Within the Vegetative Canopy of a Corn Crop 1

摘要

At several heights and times of day within a crop of Zea mays, internal leaf diffusion resistance (ri) and external boundary layer diffusion resistance (ra) were evaluated by measuring the temperature of a transpiring and a non-transpiring leaf (simulated by covering both sides of a normal leaf with strips of poly-ethylene tape), and by measuring the immediate air temperature, humidity and windspeed.