Light Acclimation by Laurel Oak Seedlings
Results
Effects
of Site - Photosynthesis of seedlings at site 2 was greater than
at site 1, possibly due to higher light levels.
Effects of Gap - Photosynthesis was significantly greater for seedlings growing in gaps than for seedlings growing under a closed canopy for all light levels except 75 µmol/m2/s in both 1999 and 2000. Maximum photosynthesis was approximately 50% of that observed in seedlings growing in full sunlight in 2000.
Effects of Gap - Photosynthesis was significantly greater for seedlings growing in gaps than for seedlings growing under a closed canopy for all light levels except 75 µmol/m2/s in both 1999 and 2000. Maximum photosynthesis was approximately 50% of that observed in seedlings growing in full sunlight in 2000.
Effects
of Trench - Trenching did not affect seedling photosynthesis in
either year.
Acclimation Mechanism - Photosynthetic rates of seedlings from gap and non-gap conditions differed even when stomatal conductance was similar. Hence, photosynthesis of seedlings growing under a closed canopy was not limited by stomatal conductance, but by some difference in leaf structure.
