Marine Biology

, Volume 160, Issue 3, pp 591–605 | Cite as

Diurnal variation in chlorophyll fluorescence of Thalassia testudinum seedlings in response to controlled salinity and light conditions

Original Paper

Abstract

Diurnal variability in chlorophyll fluorescence caused by dynamic irradiance conditions is an important issue when using pulse amplitude modulation fluorometry to measure physiological conditions of plants at the landscape scale. We examined the use of slopes and y-intercepts of diurnal effective photochemical efficiency of photosystem II (PSII) (ΔF/F m′) versus photosynthetically active radiation (PAR) regressions in addition to direct measurements of maximum photochemical efficiencies of PSII (F v/F m) values to assess physiological status of Thalassia testudinum seedlings in a controlled mesocosm study. Seedlings were exposed to two light treatments (full sun and 50–70 % light reduction) and three salinity treatments (20, 35, and 50). Measurements were taken at 0600, 0900, 1200, 1500, 1800, and 2100 hours in order to assess the diurnal variation in photochemical efficiency of PSII and PAR, with measurements at 2100 providing F v/F m. Results indicated significant effects of light and salinity on regression y-intercepts and measured F v/F m values. Shaded seedlings had higher values for both parameters, suggesting low-light acclimation. The highest salinity treatment resulted in significant reductions for both parameters, suggesting stress. Stress was also indicated by significant reductions in both seedling leaf growth and mean differences between seedling leaves and media osmolalities in the hypersaline treatments (152.0 ± 26.4 vs. 630 ± 40.2 mmol kg−1 for the control treatments). Slopes of ΔF/F m′ versus PAR significantly differed with varying light treatments, with full sun seedlings exhibiting shallower slopes than shaded seedlings, indicating higher efficiency of dissipation of excess energy (photoprotection). These experimental results confirm field data suggesting that diurnal ΔF/F m′ versus PAR regressions are responsive to changes in the physiological status of T. testudinum and that the y-intercepts of diurnal regressions may be used as a proxy for F v/F m.

Notes

Acknowledgments

This research was funded by a grant from the Florida Fish and Wildlife Conservation Commission (Grant Nos. 509620 and 56990) supported by a cooperative agreement with the South Florida Water Management District (SFWMD #4600001348). The authors would like to thank Justin Campbell of Florida International University, Miami Florida for collecting and shipping the T. testudinum seedlings.

References

  1. Becker G, Norman J, Moholl-Siebert M (1990) Two sites of heat-induced damage to photosystem II. In: Baltscheffsky M (ed) Current research in photosynthesis, vol IV. Kluwer, Dordrecht, pp 705–708Google Scholar
  2. Beer S, Bjork M, Gademann R, Ralph PJ (2001) Measurement of photosynthesis in seagrasses. In: Short FT, Coles R (eds) Global seagrass research methods. Elsevier Publishers, Amsterdam, pp 183–198CrossRefGoogle Scholar
  3. Belshe EF, Durako MJ, Blum JE (2007) Photosynthetic rapid light curves (RLC) of Thalassia testudinum exhibit diurnal variation. J Exp Mar Biol Ecol 342:253–268CrossRefGoogle Scholar
  4. Bite JS, Campbell SJ, McKenzie LJ, Coles RG (2007) Chlorophyll fluorescence measures of seagrasses Halophila ovalis and Zostera capricorni reveal differences in response to experimental shading. Mar Biol 152:405–414CrossRefGoogle Scholar
  5. Borum J, Pedersen O, Greve TM, Frankovich TA, Zieman JC, Fourqurean JW, Madden CJ (2005) The potential role of plant oxygen and sulphide dynamics in die-off events of the tropical seagrass, Thalassia testudinum. J Ecol 93:148–158CrossRefGoogle Scholar
  6. Boyer JN, Kelble CR, Ortner PB, Rudnick DT (2009) Phytoplankton bloom status: chlorophyll a biomass as an indicator of water quality condition in the southern estuaries of Florida, USA. Ecol Ind 9s:s56–s67CrossRefGoogle Scholar
  7. Brand LE (2002) The transport of terrestrial nutrients to South Florida coastal waters. In: Porter JW, Porter KG (eds) The Everglades, Florida Bay, and Coral Reefs of the Florida Keys: an ecosystem sourcebook. CRC Press, Boca Raton, pp 353–406Google Scholar
  8. Brown BE, Ambarsari I, Warner ME, Fitt WK, Dunne RP, Gibb SW, Cummings DG (1999) Diurnal changes in photochemical efficiency and xanthophyll concentrations in shallow water reef corals: evidence for photoinhibition and photoprotection. Coral Reefs 18:99–105CrossRefGoogle Scholar
  9. CERP (2001) Report for the comprehensive everglades restoration plan. South Florida Water Management District, West Palm Beach, FLGoogle Scholar
  10. Collier CJ, Lavery PS, Ralph PJ, Masini RJ (2008) Physiological characteristics of the seagrass Posidonia sinuosa along a depth-related gradient of light availability. Mar Ecol Prog Ser 353:65–79CrossRefGoogle Scholar
  11. Czerny AB, Dunton KH (1995) The effects of in situ light reduction on the growth of two subtropical seagrasses, Thalassia testudinum and Halodule wrightii. Estuaries 18:418–427CrossRefGoogle Scholar
  12. Dawes CJ, Lobban CS, Tomasko DA (1989) Comparison of the physiological ecology of the seagrasses Halophila decipiens Ostenfeld and H. johnsonii Eiseman from Florida. Aquat Bot 33:149–154CrossRefGoogle Scholar
  13. Demmig-Adams B, Adams WW III (1992) Photoprotection and other responses of plants to high light stress. A Rev Pl Physiol (Pl molec Biol) 43:599–626CrossRefGoogle Scholar
  14. Demmig-Adams B, Adams W III, Ebbert V, Logan BA (1999) Ecophysiology of the xanthophyll cycle. In: Frank HA, Young AJ, Britton G, Cogdell RJ (eds) The photochemistry of carotenoids. Kluwer Academic Publishers, Dordrecht, pp 245–269Google Scholar
  15. Dennison WC, Alberte RS (1985) Role of daily light period in the depth distribution of Zostera marina (eelgrass). Mar Ecol Prog Ser 25:51–61CrossRefGoogle Scholar
  16. Dennison WC, Orth RJ, Moore KA, Stevenson JC, Carter V, Kollar S, Bergstrom PW, Batuik RA (1993) Assessing water quality with submersed vegetation. Bioscience 43:86–94CrossRefGoogle Scholar
  17. Durako MJ (2012) Using PAM fluorometry for landscape-level assessment of Thalassia testudinum: can diurnal variation in photochemical efficiency be used as an ecoindicator of seagrass health? Ecol Ind 18:243–251CrossRefGoogle Scholar
  18. Durako MJ, Kunzelman JI (2002) Photosynthetic characteristics of Thalassia testudinum measured in situ by pulse-amplitude modulated (PAM) fluorometry: methodological and scale-based considerations. Aquat Bot 73:173–185CrossRefGoogle Scholar
  19. Durako MJ, Kuss KM (1994) Effects of Labyrinthula infection on the photosynthetic capacity of Thalassia testudinum. Bull Mar Sci 54:727–732Google Scholar
  20. Durako MJ, Barber TR, Bugden JBC, Carlson PK, Fourqurean JW, Jones RD, Porter D, Robblee MB, Yarbro LA, Zieman RT, Zieman JC (1994) Seagrass die-off in Florida Bay. In: Douglas, J (ed) Proceedings of the Gulf of Mexico Symposium. US. EPA, Tarpon Springs, FL, 14–15Google Scholar
  21. Durako MJ, Hall MO, Merello M (2002) Patterns of change in the seagrass dominated Florida Bay hydroscape. In: Porter JW, Porter KG (eds) The Everglades, Florida Bay and Coral Reefs of the Florida Keys: an ecosystem sourcebook. CRC Press, Boca Raton, pp 523–537Google Scholar
  22. Falkowski PG, Raven JA (2007) Aquatic photosynthesis, 2nd edn. Blackwell, MaldenGoogle Scholar
  23. Falkowski PG, Jokeil PL, Kinzie RA (1990) Irradiance and corals. In: Dubinski Z (ed) Ecosystems of the world—coral reefs. Elsevier, Amsterdam, pp 89–107Google Scholar
  24. Fernández-Torquemada Y, Sánchez-Lizaso JL (2005) Effects of salinity on leaf growth and survival of the Mediterranean seagrass Posidonia oceanica (L.) Delile. J Exp Mar Biol Ecol 320:57–63CrossRefGoogle Scholar
  25. Gorbunov MY, Kolber ZS, Lesser MP, Falkowski PG (2001) Photosynthesis and photoprotection in symbiotic corals. Limnol Oceanogr 46(1):75–85CrossRefGoogle Scholar
  26. Hall MO, Durako MJ (2011) South Florida Fisheries Habitat Assessment Program. Ann Rept for Comprehensive Everglades Restoration Program (CERP) Monitoring and Assessment Plan (MAP)Google Scholar
  27. Herbert DA, Fourqurean JW (2009) Phosphorus availability and salinity control productivity and demography of the seagrass Thalassia testudinum in Florida Bay. Estuaries Coasts 32:188–201CrossRefGoogle Scholar
  28. Jagels R (1973) Studies of a marine grass. Thalassia testudinum. I. Ultra structure of the osmoregulatory leaf cells. Am J Bot 60:1003–1009CrossRefGoogle Scholar
  29. Kahn AE, Durako MJ (2006) Thalassia testudinum seedling responses to changes in salinity and nitrogen levels. J Exp Mar Biol Ecol 335:1–12CrossRefGoogle Scholar
  30. Kirk JTO (1994) Light and photosynthesis in aquatic ecosystems. Cambridge University Press, CambridgeCrossRefGoogle Scholar
  31. Koch MS, Schopmeyer SA, Kyhn-Hansen C, Madden CJ, Peters JS (2007a) Tropical seagrass species tolerance to hypersalinity stress. Aquat Bot 86:14–24CrossRefGoogle Scholar
  32. Koch MS, Schopmeyer SA, Holmer M, Madden CJ, Kyhn-Hansen C (2007b) Thalassia testudinum response to the interactive stressors hypersalinity, sulfide, and hypoxia. Aquat Bot 87:104–110CrossRefGoogle Scholar
  33. Kraemer GP, Hanisak MD (2000) Physiological and growth responses of Thalassia testudinum to environmentally relevant periods of low irradiance. Aquat Bot 67:287–300CrossRefGoogle Scholar
  34. Kromkamp J, Forster R (2003) The use of variable fluorescence measurements in aquatic ecosystems: differences between multiple and single turnover measuring protocols and suggested terminology. Euro J Phycol 38:103–112CrossRefGoogle Scholar
  35. Kurzbaum E, Beer S, Eckert W (2010) Alterations in delayed and direct phytoplankton fluorescence in response to the diurnal light cycle. Hydrobiologia 639(1):197–203CrossRefGoogle Scholar
  36. Lee KS, Dunton KH (1997) Effects of in situ light reduction on the maintenance, growth and partitioning of carbon resources in Thalassia testudinum Banks ex König. J Exp Mar Biol Ecol 210:53–73CrossRefGoogle Scholar
  37. Levy O, Dubinsky Z, Schneider K, Achituv Y, Zakai D, Gorbunov MY (2004) Diurnal hysteresis in coral photosynthesis. Mar Ecol Prog Ser 268:105–117CrossRefGoogle Scholar
  38. Major KM, Dunton KH (2002) Variations in light-harvesting characteristics of the seagrass Thalassia testudinum: evidence for photoacclimation. J Exp Mar Biol Ecol 275:173–189CrossRefGoogle Scholar
  39. Marín-Guirao L, Sandoval-Gil JM, Ruíz JM, Sánchez-Lizaso JL (2011) Photosynthesis, growth and survival of the Mediterranean seagrass Posidonia oceanica in response to simulated salinity increases in a laboratory mesocosm system. Est Coast Shelf Sci 92:286–296CrossRefGoogle Scholar
  40. Murphy LR, Kinsey ST, Durako MJ (2003) Physiological effects of short-term salinity changes on Ruppia maritima. Aquat Bot 75:293–309CrossRefGoogle Scholar
  41. Parida AK, Das AB, Mittra B (2003) Effects of NaCl stress on the structure, pigment complex composition, and photosynthetic activity of mangrove Bruguiera parviflora chloroplasts. Photosynthetica 41(2):191–200CrossRefGoogle Scholar
  42. Ralph PJ, Gademann R (2005) Rapid light curves: a powerful tool for the assessment of photosynthetic activity. Aquat Bot 82:222–237CrossRefGoogle Scholar
  43. Ralph PJ, Gademann R, Dennison WC (1998) In situ sea-grass photosynthesis measured using a submersible, pulse-amplitude modulated fluorometer. Mar Biol 132:367–373CrossRefGoogle Scholar
  44. Ralph PJ, Smith RA, Macinnis-Ng CMO, Seery CR (2007a) Use of fluorescence based ecotoxicological bioassays in monitoring toxicants and pollution in aquatic systems. Rev Toxcol Environ Chem 89:589–607CrossRefGoogle Scholar
  45. Ralph PJ, Durako MJ, Enriquiz S, Collier CJ, Doblin MA (2007b) Impact of light limitation on seagrasses. J Exp Mar Biol Ecol 350:176–193CrossRefGoogle Scholar
  46. Robblee MB, Barber TR, Carlson PR, Durako MJ, Fourqurean JW, Muehlstein LK, Porter D, Yarbro LA, Zieman RT, Zieman JC (1991) Mass mortality of the tropical seagrass Thalassia testudinum in Florida Bay (USA). Mar Ecol Prog Ser 71:297–299CrossRefGoogle Scholar
  47. Rudnick DT, Madden C, Kelly S, Bennett R, Cuniff K (2006) Report on algae blooms in eastern Florida Bay and southern Biscayne Bay. Sout Florida Water Management District ReptGoogle Scholar
  48. Ruiz JM, Romero J (2001) Effects of in situ experimental shading on the Mediterranean seagrass Posidonia oceanica. Mar Ecol Prog Ser 215:107–120CrossRefGoogle Scholar
  49. Schreiber U (1983) Chlorophyll fluorescence yield changes as a tool in plant physiology. 1. The measuring system. Photosyn Res 4(4):361–373CrossRefGoogle Scholar
  50. Schreiber U (2004) Pulse-amplitude (PAM) fluorometry and saturation pulse method. In: Papageorgiou G, Govindjee (eds) Chlorophyll fluorescence: a signature of photosynthesis. Advances in photosynthesis and respiration series. Kluwer Academic Publishers, DordrechtGoogle Scholar
  51. Silva J, Santos R (2003) Daily variation patterns in seagrass photosynthesis along a vertical gradient. Mar Ecol Prog Ser 257:37–44CrossRefGoogle Scholar
  52. Sokal RR, Rohlf FJ (1995) Biometry, 3rd ed. Freeman, New York, NYGoogle Scholar
  53. Steinman AD, Havens KE, Carrick HJ, Van Zee R (2002) The past, present, and future hydrology and ecology of Lake Okeechobee and its watershed. The Everglades, Florida Bay, and Coral Reefs of the Florida Keys: an ecosystem sourcebook. CRC Press, Boca Raton, pp 19–37Google Scholar
  54. Touchette BW (2007) Seagrass-salinity interactions: physiological mechanisms used by submersed marine angiosperms for a life at sea. J Exp Mar Biol Ecol 350:194–215CrossRefGoogle Scholar
  55. UNESCO (1985) The international system of units (SI) in oceanography, UNESCO Technical Papers No. 45, IAPSO Pub. Sci. No. 32, Paris, FranceGoogle Scholar
  56. Whitfield PE, Kenworthy WJ, Durako MJ, Hammerstrom KK, Merello MF (2004) Recruitment of Thalassia testudinum seedlings into physically disturbed seagrass beds. Mar Ecol Prog Ser 267:121–131CrossRefGoogle Scholar
  57. Xia J, Li Y, Zou D (2004) Effects of salinity stress on PSI in Ulva lactuca as probed by chlorophyll fluorescence measurements. Aquat Bot 80:129–137CrossRefGoogle Scholar
  58. Zieman JC (1982) The ecology of the seagrasses of South Florida: a community profile. U.S. Fish and Wildlife Services, Washington, p 158Google Scholar
  59. Zieman JC, Fourqurean JW, Iverson RL (1989) Distribution, abundance and productivity of seagrasses and macroalgae in Florida Bay. Bull Mar Sci 44:292–311Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Department of Biology and Marine Biology, Center for Marine ScienceThe University of North Carolina WilmingtonWilmingtonUSA

Personalised recommendations