Figure 4.

Depth and light dependency of ChlF-derived F_v/F_m, ${\text{F}}_{\text{q}}^{\prime }$/${\text{F}}_{\text{m}}^{\prime }$ and ${\text{F}}_{\text{q}}^{\prime }$/${\text{F}}_{\text{v}}^{\prime }$ from FRRF measurements. (A) F_v/F_m, ${\text{F}}_{\text{q}}^{\prime }$/${\text{F}}_{\text{m}}^{\prime }$ and ${\text{F}}_{\text{q}}^{\prime }$/${\text{F}}_{\text{v}}^{\prime }$ vs. depth; (B) F_v/F_m, ${\text{F}}_{\text{q}}^{\prime }$/${\text{F}}_{\text{m}}^{\prime }$ and ${\text{F}}_{\text{q}}^{\prime }$/${\text{F}}_{\text{v}}^{\prime }$ vs. light. The red, olive and blue dashed lines represent the averaging of F_v/F_m, ${\text{F}}_{\text{q}}^{\prime }$/${\text{F}}_{\text{m}}^{\prime }$ and ${\text{F}}_{\text{q}}^{\prime }$/${\text{F}}_{\text{v}}^{\prime }$, respectively.