COMPARATIVE EFFECTS OF ALTERING LEAF TEMPERATURES AND AIR HUMIDITIES ON VAPOR PRESSURE GRADIENTS
Open Access
- 30 June 1936
- journal article
- research article
- Published by Oxford University Press (OUP) in Plant Physiology
- Vol. 11 (3) , 595-603
- https://doi.org/10.1104/pp.11.3.595
Abstract
Curves based on standard tables of vapor pressures of water are presented which show the effects of raising leaf temp. above air temp. upon the vapor pressure gradients between leaf and air when it is assumed that the leaf intercellular spaces remain at saturation. Some curves show the effects of rise or fall of leaf temp. in terms of an equivalent lowering or raising of air humidity. Other curves show the effects of raising leaf temp. on vapor pressure gradients in terms of mm. of mercury. A rise in leaf temp. to 10[degree]C above the air (over the range from 10[degree] to 30[degree]C) may increase the vapor pres-sure gradient from leaf to air by 8 to 30 mm. of mercury or by an amount equivalent to a lowering of the air humidity by 67-90% of that at saturation. The influence of temp. differences between leaf and air on transpiration is briefly discussed.This publication has 1 reference indexed in Scilit:
- LEAF TEMPERATURES AND THE COOLING OF LEAVES BY RADIATIONPlant Physiology, 1936