The daily behaviour of the effective quantum yield of PSII (ΦPSII) and of the relative electron transport rate (rETR) was assessed for 30 Gracilaria bundles haphazardly chosen from the 3 experimental sections. Measurements of the maximal quantum yield of PSII (Fv/Fm), were made before and after the daily irradiance peak, on dark adapted (30 min) Gracilaria branches (n=30) grown at sites L1, L2 and L3.
Fig. 2.
Additionally, Gracilaria samples were collected (n=10), transported
to the laboratory in a cooler box and kept in similar water
temperature (14 °C) and under dim light conditions. Less than 24 h
after collection, photosynthesis vs. light curves (P–I) were obtained
through Rapid Light Curves (RLC) generated with increasing light
intensities up to 430 μmol photons m−2 s−1. During this process, the
seaweed material was kept in a thermal bath around 14 °C. The
effective quantum yield of PSII (ΦPSII) was obtained for each given
light pulse and the electron transport rate (ETR) was calculated as: