Figure Captions
Figure 1 – Diurnal air temperature (T), photosynthetically active radiation (Q), and relative humidity (RH) used for modellingAnet in all species. Dates indicate the environmental conditions at the University of New Mexico in 2018. Grey regions indicate night.
Figure 2 – Diurnal variation of apparent Vcmax(a, b, c) and Jmax (d, e, f) show consistent declines by the end of day at 25 °C in Populus deltoides (a, d;N = 6), Capsicum annuum (b, e; N = 6), Malus domestica (b, e; N = 6), Populus trichocarpa (b, e;N = 4) but not Pinus ponderosa (c, f; N = 3). At 30 °C there are diurnal declines in photosynthetic capacity inAsclepias speciosa (Jmax only; d; N= 6), Quercus muehlenbergii (a, d; N = 5), Rosa grandiflora (b, e; N = 6), and Ginkgo biloba (c, f;N = 3) but not in Cedrus deodar (c, f; N = 4). Data presented as means ± s.e.m.
Figure 3 – Apparent max is strongly correlated with apparent Vcmax across all species. Data presented as means for each timepoint for each species; s.e.m. was not included for clarity.
Figure 4 – Relative Vcmax (a-c) andJmax (d-f) for all species shown in Fig. 1. Data presented as means ± s.e.m.
Figure 5 – Modelled diurnal Anet forAsclepias speciosa (a), Capsicum annuum (b), Malus domestica (c), Quercus muehlenbergii (d), Populus deltoides (e), Populus trichocarpa (f), Rosa grandiflora(g), Ginkgo biloba (h), Pinus ponderosa (i), andCedrus deodar (j) under conditions of constant maximumVcmax and Jmax (Peak), and diurnally changing Vcmax andJmax (Changing), constant meanVcmax and Jmax (Average), and constant minimum Vcmax andJmax .
Figure 6 – Apparent Vcmax (a),Jmax (b), and Anet (c) did not decline significantly after 5 one-minute clamps on the same leaf spot of individuals of Populus deltoides , Capsicum annuum , and Populus trichocarpa. N = 6, data presented as means ± s.e.m.
Figure 7 – Modelled versus measured net CO2assimilation (Anet ) (a) and stomatal conductance (gs ). Solid line indicates 1:1 relationship. See text for statistics.