Abstract
Heterogeneity in photosynthetic performance between polyp and coenosarc tissue in corals was shown using a new variable fluorescence imaging system (Imaging-PAM) with three species of coral, Acropora nobilis, Cyphastrea serailia and Pocillopora damicornis. In comparison to earlier studies with fibre-optic microprobes for fluorescence analysis, the Imaging-PAM enables greater accuracy by allowing different tissues to be better defined and by providing many more data points within a given time. Spatial variability of photosynthetic performance from the tip to the distal parts was revealed in one species of branching coral, A. nobilis. The effect of bleaching conditions (33°C vs. 27°C) was studied over a period of 8 h. Marked changes in fluorescence parameters were observed for all three species. Although a decline in ΦPSII (effective quantum yield) and Yi (the first effective quantum yield obtained from a rapid light curve) were observed, P. damicornis showed no visual signs of bleaching on the Imaging-PAM after this time. In A. nobilis and C. serailia, visual signs of bleaching over the 8 h period were accompanied by marked changes in F (light-adapted fluorescence yield), NPQ (non-photochemical quenching) and E k (minimum saturating irradiance), as well as ΦPSII and Yi. These changes were most marked over the first 5 h. The most sensitive species was A. nobilis, which after 8 h at 33°C had reached a ΦPSII value of almost zero across its whole surface. Differential bleaching responses between polyps and coenosarc tissue were found in P. damicornis, but not in A. nobilis and C. serailia. NPQ increased with exposure time to 33°C in both the latter species, accompanied by a decreasing E k, suggesting that the xanthophyll cycle is entrained as a mechanism for reducing the effects of the bleaching conditions.
Similar content being viewed by others
References
Bruno JF, Siddon CE, Witman JD, Colin PL, Toscano MA (2001) El Niño related coral bleaching in Palau, western Caroline Islands. Coral Reefs 20:127–136
Cook CB, Logan A, Ward J, Luckhurst B, Berg CJ (1990) Elevated temperatures and bleaching on a high-latitude coral reef: the Bermuda event. Coral Reefs 9:45–49
Fitt WK, Spero HJ, Halas J, White MW, Porter JW (1993) Recovery of the coral Montastrea annularis in the Florida Keys after the 1987 Caribbean ‘bleaching event’. Coral Reefs 12:57–64
Fitt WK, Brown BE, Warner ME, Dunne RP (2001) Coral bleaching: interpretation of thermal tolerance limits and thermal thresholds in tropical corals. Coral Reefs 20:51–65
Gilmore AM, Shinkarev VP, Hazlett TL, Govindjee (1998) Quantitative analysis of the effects of intrathylakoid pH and xanthophyll cycle pigments on chlorophyll alpha fluorescence lifetime distributions and intensity in thylakoids. Biochemistry 37:13582–13593
Harrison WG, Platt T (1986) Photosynthesis–Irradiance relationships in polar and temperate phytoplankton populations. Polar Biol 5:153–164
Helmuth BST, Timmerman BEH, Sebens KP (1997) Interplay of host morphology and symbiont microhabitat in coral aggregations. Mar Biol 130:1–10
Henley WJ (1993) Measurement and interpretation of photosynthetic light-response curves in algae in the context of photoinhibition and diel changes. J Phycol 29:729–739
Hoegh-Guldberg O (1999) Climate change, coral bleaching and the future of the world’s coral reefs. Mar Freshw Res 50:839–866
Hoegh-Guldberg O, Smith GJ (1989) The effect of sudden changes in temperature, light and salinity on the population density and export of zooxanthellae from the reef Stylophora pistillata Esper and Seriatopora hystrix Dana. J Exp Mar Biol Ecol 129:279–303
Jones RJ, Hoegh-Guldberg O (1999) Effects of cyanide on coral photosynthesis: implications for identifying the cause of coral bleaching and for assessing the environmental effects of cyanide fishing. Mar Ecol Prog Ser 177:83–91
Jones RJ, Hoegh-Guldberg O, Larkum AWD, Schreiber U (1998) Temperature-induced bleaching of corals begins with impairment of the CO2 fixation metabolism in zooxanthellae. Plant Cell Environ 21:1219–1230
Kolbowski J, Schreiber U (1995) Computer-controlled phytoplankton analyzer based on 4-wavelengths PAM chlorophyll fluorometer. In: Mathis P (ed) Photosynthesis: from light to biosphere, vol V. Kluwer, Dordrecht, pp 825–828
Kühl M, Revsbech NP (2001) Biogeochemical microsensors for boundary layer studies. In: Boudreau BP, Jørgensen BB (eds) The benthic boundary layer. Oxford University Press, Oxford, pp 180–210
Kühl M, Cohen Y, Dalsgaard T, Barker JB, Revsbech NP (1995) Microenvironment and photosynthesis of zooxanthellae in scleractinian coral studies with microsensors for O2, pH and light. Mar Ecol Prog Ser 117:159–172
Lewis AE (1966) Biostatistics. Reinhold, New York
Marshall PA, Baird AH (2000) Bleaching of corals on the Great Barrier Reef: differential susceptibilities among taxa. Coral Reefs 19:155–163
Platt T, Gallegos CL, Harrison WG (1980) Photoinhibition of photosynthesis in natural assemblages of marine phytoplankton. J Mar Res 38:687–701
Ralph PJ, Gademann R, Larkum AWD (2001) Zooxanthellae expelled from bleached corals at 33°C are photosynthetically competent. Mar Ecol Prog Ser 220:163–168
Ralph PJ, Gademann R, Larkum AWD, Kühl M (2002) Spatial heterogeneity in active chlorophyll fluorescence and PSII activity of coral tissues. Mar Biol 141:639–646
Ravindran J, Raghukumar C, Raghukumar S (1999) Disease and stress-induced mortality of corals in Indian reefs and observations on bleaching of corals in the Andamans. Curr Sci 76:233–237
Rowan R, Knowlton N (1995) Intraspecific diversity and ecological zonation in coral–algal symbiosis. Proc Natl Acad Sci USA 92:2850–2853
Salih A, Larkum AWD, Cox G, Kühl M, Hoegh-Guldberg O (2000) Fluorescent pigments in corals are photoprotective. Nature 408:850–853
Szmant AM, Gassman NJ (1990) The effects of prolonged bleaching on the tissue biomass and reproduction of the reef coral Montastrea annularis. Coral Reefs 8:217–224
Warner ME, Fitt WK, Schmidt GW (1996) The effects of elevated temperature on the photosynthetic efficiency of zooxanthellae in hospite from four different species of reef coral: a novel approach. Plant Cell Environ 19:291–299
Warner ME, Fitt WK, Schmidt GW (1999) Damage to photosystem II in symbiotic dinoflagellates: a determinant of coral bleaching. Proc Natl Acad Sci USA 96:8007–8012
Yentsch CS, Yentsch CM, Cullen JJ, Lapointe B, Phinney DA, Yentsch SW (2002) Sunlight and water transparency: cornerstones in coral research. J Exp Mar Biol Ecol 268:171–183
Acknowledgements
We thank N. Ralph for the construction of the flow-through chambers and the staff of Heron Island Research Station for support. Specimens were collected under Great Barrier Reef Marine Park Authority permit G01/623. The Australian Research Council, the University of Technology, Sydney, and the University of Sydney provided funding support for A.W.D.L. and P.J.R. The Danish Natural Science Research Council supported M.K. (contract no. 9700549). The experiments comply with the current laws of Australia.
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by L. Hagerman, Helsingør
Rights and permissions
About this article
Cite this article
Hill, R., Schreiber, U., Gademann, R. et al. Spatial heterogeneity of photosynthesis and the effect of temperature-induced bleaching conditions in three species of corals. Marine Biology 144, 633–640 (2004). https://doi.org/10.1007/s00227-003-1226-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00227-003-1226-1