Scaling-Up Gas Exchange and Energy Balance from the Leaf to the Canopy Level

Abstract

Having discussed the gas exchange and energy balance of individual leaves in previous chapters, we are now in a position to “scale up” to the canopy level. In moving between scales, it is important to determine which interactions are strong enough to be considered and which can be ignored. The water relations of plant canopies differ distinctly from what would be predicted from the study of individual leaves, because each leaf modifies the environment of adjacent leaves by reducing irradiance and wind speed, and either decreasing or increasing vapor pressure deficit, depending on transpiration rates.