[O-11] Senior high school student poster presentations

[O11-P91] Fluorescence and Photosynthetic Activity of Corals in Kikai Island

*ayane ohmori¹ (1.Kikai high school/Sangoryuugaku, 2.KIKAI institute for Coral Reaf Sciences)

In this study, we investigated the relationship between coral bleaching progression, photosynthetic activity, and fluorescence intensity in reef-building corals inhabiting Kikai Island, Kagoshima Prefecture. Coral samples were collected from tide pools along the Shirouzu coast and included species such as Favites chinensis and Acropora spp. Fluorescence was photographed under UV light, and fluorescence intensity (G/B ratio) was analyzed using ImageJ. Photosynthetic activity (Fv/Fm) was measured using the PAM fluorometry method. The results showed no correlation between water depth and fluorescence intensity or photosynthetic activity in non-bleached corals, although Acropora spp. exhibited higher fluorescence. In bleached corals, photosynthetic activity was lower, but fluorescence intensity did not show a significant difference. A tendency for corals with lower photosynthetic activity to exhibit stronger fluorescence was observed. This suggests that corals may increase fluorescence to attract symbiotic zooxanthellae in response to bleaching. Future research will focus on how light intensity affects coral fluorescence under controlled aquarium conditions with stable water temperatures.