Photo-physiology of healthy and bleached corals from the Mascarene Plateau

• DOI: 10.4314/wiojms.si2021.2.8
• Publication Date: 2022-07-21T12:53:28Z
• Authors: Ranjeet Bhagooli; Mouneshwar Soondur; Sundy Ramah; Arvind Gopeechund; Sruti Jeetun; Deepeeka Kaullysing
• Keywords: Acropora; Zooxanthellae; Symbiodinium; Photoinhibition; Porites; Stylophora pistillata; Coral bleaching; Anthozoa

This study presents the first report of variable photo-physiology healthy-looking and bleached corals from upper mesophotic waters Mascarene Plateau. In May 2018, during FAO EAF-Nansen research expedition cruise, coral bleaching was visually observed. Five species Saya de Malha Bank, namely Heliopora coerulea, Favites sp. Porites 27 m Acropora Lithophyllon repanda 30 m, three Nazareth Galaxea fascicularis 36 Stylophora-like 58 were studied using Video-Assisted Multi-Sampler (VAMS) collected a Van Veen grab. Chlorophyll fluorescence parameters such as effective quantum yield at photosystem II (ΦPSII), relative maximum electron transport rate (rETRm), photosynthetic efficiency (α), photoinhibition (β), saturating light level (Ek), non-photochemical quenching (NPQm) measured Diving-Pulse-Amplitude-Modulated (D-PAM) fluorometer to in non-bleached corals. All photo-physiological varied significantly among tested between conditions, except for β. The interaction conditions only significant case β, but generally not significant. A two-way ANOVA indicated effects depth on almost all parameters, effect rETRmax α, along with its Ek. ΦPSII did differ parts while it decreased m. NPQm change Porites, (30 m) tended increase Heliopora, (36 m), Lithophyllon, Galaxea, decrease Favities, Stylophora-like. thermally tolerant exhibited normal even Favites, dysfunctioning. revealed that seven Plateau are spared phenomenon exhibit conditions. Further studies warranted thoroughly understand patterns severity summer periods Banks.