Abstract
One of the means to measure photosynthetic health in corals and cnidarians is through measuring the chlorophyll fluorescence. In this study, the photosynthetic performance in three individuals of Heteractis magnifica was being evaluated using a submersible pulse modulated amplitude fluorometer (Diving PAM). The effective quantum yield of each individual was monitored for three consecutive days in five different times (0600, 0900, 1200, 1500, 1800) throughout the whole day. The photosynthetic rate during the diurnal changes showed an opposite pattern to photosynthetic active radiation (PAR) light intensity, being the lowest at 1200-1500 hours and recovered in the evening as the PAR light intensity declined. There were no significant differences in the yield values of the light adapted (ΔF’/Fm’) and the dark-adapted (Fv/Fm) anemones (ANOVA, p>0.05), with 0.75±0.08 and 0.74±0.11, respectively. This information can be used as the baseline data for further guidance of monitoring stress in the corals and cnidarians in the surrounding waters in Pulau Tioman.
