Keywords: غلظت غیر فتوشیمیایی فلورسانس کلروفیل; Broadleaved evergreens; Energy flux; Energy partition; Quercus myrsinaefolia; Machilus thunbergii; Amax; the potential photosynthetic rate; Anet; the net photosynthesis under natural sunlight; Chl; Chlorophyll; F; steady-state fluorescence; Fm, Fo and Fv;