Annals of Botany

A stochastic model of sunlit-shaded patterns in canopies

Diurnal changes in solar position plus occlusion caused by overlapping foliage means that throughout a day, leaves alternate between periods where they are either sunlit or shaded. Describing these patterns for real plant canopies is difficult and computationally intensive.

Diagram of light dynamics

Retkute et al. combine high-resolution reconstructions of field-grown plants with ray-tracing to analyse how light dynamics vary for different plant species, planting densities and leaf area indices. They develop a stochastic model which involves two states, sunlit and shaded, where the rates of switching between states are a function of time of day and the depth within the canopy.