Effects of shading on seagrass morphology and thermal optimal of productivity
Eunice Kong A B E , Yan Xiang Ow
C , Samantha Lai A , Siti Maryam Yaakub D and Peter Todd A
+ Author Affiliations
- Author Affiliations
A Experimental Marine Ecology Laboratory, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Block S3, Level 2, Singapore 117543, Republic of Singapore.
B National Biodiversity Centre, National Parks Board, 1B Cluny Road, Singapore 259569, Republic of Singapore.
C St John’s Island National Marine Laboratory, Tropical Marine Science Institute, National University of Singapore, 18 Kent Ridge Road, Singapore 119227, Republic of Singapore.
D DHI Water & Environment (S) Pte Ltd, 2 Venture Drive, #18–18, Vision Exchange, Singapore 608526, Republic of Singapore.
E Corresponding author. Email: eunicekong@hotmail.sg
Marine and Freshwater Research 71(8) 913-921 https://doi.org/10.1071/MF19173
Submitted: 15 May 2019 Accepted: 13 September 2019 Published: 6 December 2019
Abstract
Light and temperature are important factors affecting seagrass primary productivity. Acclimatisation to reduced light availability may affect the optimal temperature at which seagrasses photosynthesise, potentially causing synergistic effects between increasing water temperatures and decreasing light levels on coastal productivity. This study investigated the effects of reduced light availability on the morphology (leaf size, shoot density) and thermal optimal of net productivity in Halophila ovalis (R.Br.) Hook. A 12-week in situ shading experiment was conducted at Chek Jawa Wetlands, Singapore, testing high (68% shading), low (49%) and control (0%) shadings. Every 4 weeks, photosynthetic and respiration rates of H. ovalis leaves and the root–rhizome complex were measured in closed incubation chambers at temperatures from 22 to 42°C (at 4°C intervals). A fitted temperature-response model of net photosynthesis was used to estimate the thermal optimal for each shading treatment. High shading reduced shoot density (mean ± s.e.) 87.06 ± 7.86% and leaf surface area 31.72 ± 24.74%. Net productivity (6 mg O2 g–1 DW h–1) and its thermal optimal (28–30°C) were not significantly different among shading treatments throughout the experiment. Light levels appeared to have minimal influence on the thermal dependency of H. ovalis net productivity.
Additional keywords: Halophila ovalis, light limitation, net primary productivity, optimal temperature, Singapore, tropical seagrass.
References
Adams, M. P., Collier, C. J., Uthicke, S., Ow, Y. X., Langlois, L., and O’Brien, K. R. (2017). Model fit versus biological relevance: evaluating photosynthesis–temperature models for three tropical seagrass species. Scientific Reports 7, 39930.| Model fit versus biological relevance: evaluating photosynthesis–temperature models for three tropical seagrass species.Crossref | GoogleScholarGoogle Scholar | 28051123PubMed |
Biber, P. D., Paerl, H. W., Gallegos, C. L., and Kenworthy, W. J. (2005). Evaluating indicators of seagrass stress to light. In ‘Estuarine Indicators’. (Ed S. A. Bortone.) pp. 193–210. (CRC Press: Boca Raton, FL, USA.)
Bos, A. R., Bouma, T. J., de Kort, G. L. J., and van Katwijk, M. M. (2007). Ecosystem engineering by annual intertidal seagrass beds: sediment accretion and modification. Estuarine, Coastal and Shelf Science 74, 344–348.
| Ecosystem engineering by annual intertidal seagrass beds: sediment accretion and modification.Crossref | GoogleScholarGoogle Scholar |
Bulthuis, D. A. (1983). Effects of temperature on the photosynthesis–irradiance curve of the Australian seagrass, Heterozostera tasmanica. Marine Biology Letters 4, 47–57.
Bulthuis, D. A. (1987). Effects of temperature on photosynthesis and growth of seagrasses. Aquatic Botany 27, 27–40.
| Effects of temperature on photosynthesis and growth of seagrasses.Crossref | GoogleScholarGoogle Scholar |
Campbell, S. J., McKenzie, L. J., and Kerville, S. P. (2006). Photosynthetic responses of seven tropical seagrasses to elevated seawater temperature. Journal of Experimental Marine Biology and Ecology 330, 455–468.
| Photosynthetic responses of seven tropical seagrasses to elevated seawater temperature.Crossref | GoogleScholarGoogle Scholar |
Collier, C. J., and Waycott, M. (2014). Temperature extremes reduce seagrass growth and induce mortality. Marine Pollution Bulletin 83, 483–490.
| Temperature extremes reduce seagrass growth and induce mortality.Crossref | GoogleScholarGoogle Scholar | 24793782PubMed |
Collier, C. J., Waycott, M., and Ospina, A. G. (2012). Responses of four Indo-West Pacific seagrass species to shading. Marine Pollution Bulletin 65, 342–354.
| Responses of four Indo-West Pacific seagrass species to shading.Crossref | GoogleScholarGoogle Scholar | 21741666PubMed |
Collier, C. J., Ow, Y. X., Langlois, L., Uthicke, S., Johansson, C. L., O’Brien, K. R., Hrebien, V., and Adams, M. P. (2017). Optimum temperatures for net primary productivity of three tropical seagrass species. Frontiers in Plant Science 8, 1446.
| Optimum temperatures for net primary productivity of three tropical seagrass species.Crossref | GoogleScholarGoogle Scholar | 28878790PubMed |
Costanza, R., d’Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Limburg, K., Naeem, S., O’Neill, R. V., Paruelo, J., Raskin, R. G., Sutton, P., and van den Belt, M. (1997). The value of the world’s ecosystem services and natural capital. Nature 387, 253–260.
| The value of the world’s ecosystem services and natural capital.Crossref | GoogleScholarGoogle Scholar |
Dennison, W. C., Orth, R. J., Moore, K. A., Stevenson, J. C., Carter, V., Kollar, S., Bergstrom, P. W., and Batiuk, R. A. (1993). Assessing water quality with submersed aquatic vegetation. Bioscience 43, 86–94.
| Assessing water quality with submersed aquatic vegetation.Crossref | GoogleScholarGoogle Scholar |
Drew, E. A. (1979). Physiological aspects of primary production in seagrasses. Aquatic Botany 7, 139–150.
| Physiological aspects of primary production in seagrasses.Crossref | GoogleScholarGoogle Scholar |
Duarte, C. M. (1991). Seagrass depth limits. Aquatic Botany 40, 363–377.
| Seagrass depth limits.Crossref | GoogleScholarGoogle Scholar |
Eklöf, J. S., McMahon, K., and Lavery, P. S. (2009). Effects of multiple disturbances in seagrass meadows: shading decreases resilience to grazing. Marine and Freshwater Research 60, 1317–1327.
| Effects of multiple disturbances in seagrass meadows: shading decreases resilience to grazing.Crossref | GoogleScholarGoogle Scholar |
Erftemeijer, P. L. A., and Stapel, J. (1999). Primary production of deep-water Halophila ovalis meadows. Aquatic Botany 65, 71–82.
| Primary production of deep-water Halophila ovalis meadows.Crossref | GoogleScholarGoogle Scholar |
Fourqurean, J. W., Duarte, C. M., Kennedy, H., Marbà, N., Holmer, M., Mateo, M. A., Apostolaki, E. T., Kendrick, G. A., Krause-Jensen, D., McGlathery, K. J., and Serrano, O. (2012). Seagrass ecosystems as a globally significant carbon stock. Nature Geoscience 5, 505–509.
| Seagrass ecosystems as a globally significant carbon stock.Crossref | GoogleScholarGoogle Scholar |
Gordon, D. M., Grey, K. A., Chase, S. C., and Simpson, C. J. (1994). Changes to the structure and productivity of a Posidonia sinuosa meadow during and after imposed shading. Aquatic Botany 47, 265–275.
| Changes to the structure and productivity of a Posidonia sinuosa meadow during and after imposed shading.Crossref | GoogleScholarGoogle Scholar |
Granger, S., and Iizumi, H. (2001). Water quality measurement methods for seagrass habitat. In ‘Global Seagrass Research Methods’. (Eds F. T. Short and R. G. Coles.) pp. 393–406. (Elsevier: Amsterdam, Netherlands.)
Hemminga, M. A. (1998). The root/rhizome system of seagrasses: an asset and a burden. Journal of Sea Research 39, 183–196.
| The root/rhizome system of seagrasses: an asset and a burden.Crossref | GoogleScholarGoogle Scholar |
Hirth, H. F. (1971). ‘Synopsis of the Biological Data on the Green Turtle Chelonia mydas (Linnaeus 1758).’ (Food and Agriculture Organisation of the United Nations: Rome, Italy.)
IPCC (2014). ‘Climatic Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change.’ (IPCC: Geneva, Switzerland.)
Jackson, E. L., Rowden, A. A., Attrill, M. J., Bossey, S. J., and Jones, M. B. (2001). The importance of seagrass beds as a habitat for fishery species. Oceanography and Marine Biology – an Annual Review 39, 269–303.
Lee, K. S., Park, S. R., and Kim, Y. K. (2007). Effects of irradiance, temperature, and nutrients on growth dynamics of seagrasses: a review. Journal of Experimental Marine Biology and Ecology 350, 144–175.
| Effects of irradiance, temperature, and nutrients on growth dynamics of seagrasses: a review.Crossref | GoogleScholarGoogle Scholar |
Longstaff, B. J., and Dennison, W. C. (1999). Seagrass survival during pulsed turbidity events: the effects of light deprivation on the seagrasses Halodule pinifolia and Halophila ovalis. Aquatic Botany 65, 105–121.
| Seagrass survival during pulsed turbidity events: the effects of light deprivation on the seagrasses Halodule pinifolia and Halophila ovalis.Crossref | GoogleScholarGoogle Scholar |
Longstaff, B. J., Loneragan, N. R., O’donohue, M. J., and Dennison, W. C. (1999). Effects of light deprivation on the survival and recovery of the seagrass Halophila ovalis (R.Br.) Hook. Journal of Experimental Marine Biology and Ecology 234, 1–27.
| Effects of light deprivation on the survival and recovery of the seagrass Halophila ovalis (R.Br.) Hook.Crossref | GoogleScholarGoogle Scholar |
Ludlow, M. M., and Wilson, G. L. (1971). Photosynthesis of tropical pasture plants I. illuminance, carbon dioxide concentration, leaf temperature, and leaf–air vapour pressure difference. Australian Journal of Biological Sciences 24, 449–470.
| Photosynthesis of tropical pasture plants I. illuminance, carbon dioxide concentration, leaf temperature, and leaf–air vapour pressure difference.Crossref | GoogleScholarGoogle Scholar |
Maritime and Port Authority of Singapore (2017). ‘Year 2017 Singapore Tide Table.’ (Maritime and Port Authority of Singapore: Singapore.)
Maritime and Port Authority of Singapore (2018). ‘Year 2018 Singapore Tide Table.’ (Maritime and Port Authority of Singapore: Singapore.)
Marsh, J. A., Dennison, W. C., and Alberte, R. S. (1986). Effects of temperature on photosynthesis and respiration in eelgrass (Zostera marina L.). Journal of Experimental Marine Biology and Ecology 101, 257–267.
| Effects of temperature on photosynthesis and respiration in eelgrass (Zostera marina L.).Crossref | GoogleScholarGoogle Scholar |
Marsh, H., O’Shea, T. J., and Reynolds, J. E. III (2011). Feeding biology. In ‘Ecology and Conservation of the Sirenia: Dugongs and Manatees’. pp. 79–144. (Cambridge University Press: New York, NY, USA.)
Masini, R. J., Cary, J. L., Simpson, C. J., and McComb, A. J. (1995). Effects of light and temperature on the photosynthesis of temperate meadow-forming seagrasses in Western Australia. Aquatic Botany 49, 239–254.
| Effects of light and temperature on the photosynthesis of temperate meadow-forming seagrasses in Western Australia.Crossref | GoogleScholarGoogle Scholar |
McKenzie, L. J., Yaakub, S. M., Tan, R., Seymour, J., and Yoshida, R. L. (2016). Seagrass habitats of Singapore: environmental drivers and key processes. The Raffles Bulletin of Zoology 34, 60–77.
Orth, R. J., Carruthers, T. J. B., Dennison, W. C., Duarte, C. M., Fourqurean, J. W., Heck, K. L., Hughes, A. R., Kendrick, G. A., Kenworthy, W. J., Olyarnik, S., Short, F. T., Waycott, M., and Williams, S. L. (2006). A global crisis for seagrass ecosystems. Bioscience 56, 987–996.
| A global crisis for seagrass ecosystems.Crossref | GoogleScholarGoogle Scholar |
Pedersen, O., Colmer, T. D., Borum, J., Zavala‐Perez, A., and Kendrick, G. A. (2016). Heat stress of two tropical seagrass species during low tides: impact on underwater net photosynthesis, dark respiration and diel in situ internal aeration. New Phytologist 210, 1207–1218.
| Heat stress of two tropical seagrass species during low tides: impact on underwater net photosynthesis, dark respiration and diel in situ internal aeration.Crossref | GoogleScholarGoogle Scholar | 26914396PubMed |
Pisek, A., Larcher, W., Vegis, A., and Napp-Zinn, K. (1973). The normal temperature range. In ‘Temperature and Life’. (Eds H. Precht, J. Christophersen, H. Hensel, and W. Larcher.) pp. 102–194. (Springer-Verlag: Berlin, Germany.)
Ralph, P. J. (1998). Photosynthetic response of laboratory-cultured Halophila ovalis to thermal stress. Marine Ecology Progress Series 171, 123–130.
| Photosynthetic response of laboratory-cultured Halophila ovalis to thermal stress.Crossref | GoogleScholarGoogle Scholar |
Ralph, P. J., Durako, M. J., Enríquez, S., Collier, C. J., and Doblin, M. A. (2007). Impact of light limitation on seagrasses. Journal of Experimental Marine Biology and Ecology 350, 176–193.
| Impact of light limitation on seagrasses.Crossref | GoogleScholarGoogle Scholar |
Rhein, M., Rintoul, S. R., Aoki, S., Campos, E., Chambers, D., Feely, R. A., Gulev, S., Johnson, G. C., Josey, S. A., Kostianoy, A., Mauritzen, C., Roemmich, D., Talley, L. D., and Wang, F. (2013). Observations: ocean. In ‘Climate Change 2013: the Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change’. (Eds T. F. Stocker, D. Qin, G. K. Plattner, M. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P. M. Midgley.) pp. 255–315. (Cambridge University Press: Cambridge, UK.)
Silva, J., Sharon, Y., Santos, R., and Beer, S. (2009). Measuring seagrass photosynthesis: methods and applications. Aquatic Biology 7, 127–141.
| Measuring seagrass photosynthesis: methods and applications.Crossref | GoogleScholarGoogle Scholar |
Staehr, P. A., and Borum, J. (2011). Seasonal acclimation in metabolism reduces light requirements of eelgrass (Zostera marina). Journal of Experimental Marine Biology and Ecology 407, 139–146.
| Seasonal acclimation in metabolism reduces light requirements of eelgrass (Zostera marina).Crossref | GoogleScholarGoogle Scholar |
Tun, K. P. P., Chou, L. M., and Cheshire, A. C. (1998). Photophysiological studies of the soft coral Sinularia in the turbid waters of Singapore. In ‘The Marine Biology of the South China Sea III: Proceedings of the Third International Conference on the Marine Biology of the South China Sea’, 28 October–1 November 1996, Hong Kong. (Ed. B. Morton.) pp. 275–285. (Hong Kong University Press: Hong Kong SAR, PR China.)
Vermaat, J. E., Agawin, N. S. R., Duarte, C. M., Fortes, M. D., Marbà, N., and Uri, J. S. (1995). Meadow maintenance, growth and productivity of a mixed Philippine seagrass bed. Marine Ecology Progress Series 124, 215–225.
| Meadow maintenance, growth and productivity of a mixed Philippine seagrass bed.Crossref | GoogleScholarGoogle Scholar |
Waycott, M., McMahon, K., Mellors, J., Calladine, A., and Kleine, D. (2004). ‘A Guide to Tropical Seagrasses of the Indo-West Pacific.’ (James Cook University: Townsville, Qld, Australia.)
Waycott, M., Duarte, C. M., Carruthers, T. J. B., Orth, R. J., Dennison, W. C., Olyarnik, S., Calladine, A., Fourqurean, J. W., Heck, K. L., Hughes, A. R., Kendrick, G. A., Kenworthy, W. J., Short, F. T., and Williams, S. L. (2009). Accelerating loss of seagrasses across the globe threatens coastal ecosystems. Proceedings of the National Academy of Sciences of the United States of America 106, 12377–12381.
| Accelerating loss of seagrasses across the globe threatens coastal ecosystems.Crossref | GoogleScholarGoogle Scholar | 19587236PubMed |
Yaakub, S. M., Lim, R. L. F., Lim, W. L., and Todd, P. A. (2013). The diversity and distribution of seagrass in Singapore. Nature in Singapore 6, 105–111.
Yaakub, S. M., McKenzie, L. J., Erftemeijer, P. L., Bouma, T., and Todd, P. A. (2014a). Courage under fire: seagrass persistence adjacent to a highly urbanised city-state. Marine Pollution Bulletin 83, 417–424.
| Courage under fire: seagrass persistence adjacent to a highly urbanised city-state.Crossref | GoogleScholarGoogle Scholar | 24508045PubMed |
Yaakub, S. M., Chen, E., Bouma, T. J., Erftemeijer, P. L. A., and Todd, P. A. (2014b). Chronic light reduction reduces overall resilience to additional shading stress in the seagrass Halophila ovalis. Marine Pollution Bulletin 83, 467–474.
| Chronic light reduction reduces overall resilience to additional shading stress in the seagrass Halophila ovalis.Crossref | GoogleScholarGoogle Scholar | 24382468PubMed |
Yan, W., and Hunt, L. A. (1999). An equation for modelling the temperature response of plants using only the cardinal temperatures. Annals of Botany 84, 607–614.
| An equation for modelling the temperature response of plants using only the cardinal temperatures.Crossref | GoogleScholarGoogle Scholar |
