Model-simulated ROS concentration (mg O cell⁻¹), symbiont cell expulsion rate (d⁻¹) and ROS threshold (1.42 × 10⁻¹⁴ mg O cell⁻¹) in the ambient temperature treatment for the unshaded and shaded treatments (a), in comparison with experimental maximum quantum yield (dimensionless; F_v/F_m) (b), light saturation coefficient (μmol photon m⁻² s⁻¹; E_k) (c), maximum photosynthetic capacity (μmol electron m⁻² s⁻¹; rETR^MAX) (d) and alpha (dimensionless) (e), averaged |$\pm$| standard error, recorded for A. divaricata. The pink-shaded regions (b, d, e) illustrate a statistical decline in the photochemical proxies from the first sampling event. Daily tick marks occur at 0:00 h.