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= 1.2 mg mP2S -'; = 0.4;

= 1.2mgm-2 s , = 0.7; = = a = = 2) and a

When the canopy is small (L = 2), planophile canopies have faster gross photosynthesis than erect canopies, because they intercept more light. In the case of large canopies exposed to high irradiance, most of the incident radiation is intercepted by foliage, irrespective of leaf inclination. In such circumstances, erectophile canopies photosynthesize faster because light penetrates deeper into the canopy. C4 plants photosynthesize faster than C3 plants, though the effect is small at low light intensities. Canopy photosynthesis is faster at the higher incident irradiance.