Year: 1995
Type: article
Abstract: Canopy leaves assimilate CO2 more efficiently than leaves of under canopy. Since the canopy heights of tropical rain forests are high, the knowledge on the rate of photosynthesis in canopy leaves is limited. Thus, we focused on leaves of tropical canopy plants and measured diurnal changes of photosynthesis and stomatal conductance at Pasoh, Peninsula Malaysia. Access to the canopy level was performed by using a canopy walk way. The maximum photosynthetic rates were within the range detected in a number of temperate evergreen species. The maximum diurnal photosynthetic rate and stomatal conductance occurred in the early to mid-morning and then declined. The midday decrease in photosynthesis was caused by stomatal closure and also by biochemical limitations of photosynthesis. No marked differences in maximum rates of photosynthesis were not observed between dry and wet seasons. Furthermore, no seasonal changes of diurnal trends of photosynthesis and stomatal conductance were detected. From these results, we speculate that the annual photosynthetic rates of canopy leaves in tropical rain forests should be higher than the rates of leaves in temperate forests.
Source: Tropics
Authors: Kazuhiko OGINO, Akio FURUKAWA
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: bronze
OpenAlex ID: W1985765667