Sains Malaysiana 42(8)(2013): 1059–1064

Physiological Responses of Avicennia marina var. acutissima and Bruguiera

parviflora under Simulated Rise in Sea Level

(Respon Fisiologi Avicennia marina var. acutissimadan Bruguiera parviflora

di Bawah Simulasi Kenaikan Aras Air Laut)

M.Z. Rasheed, O. Normaniza* & M.Z. Rozainah

Institute of Biological Sciences, University of Malaya, 50603, Kuala Lumpur, Malaysia

Received: 1 November 2011/Accepted: 3 April 2013

ABSTRACT

Climate change components such as increased in atmospheric carbon dioxide (CO₂) and rising sea levels are likely to affect mangrove ecosystems. Healthy mature propagules of A. marina var. acutissima and B. Parviflora were subjected to two tidal treatments; shallow and deep; for six months. Shallow treatment mimicked the current tidal fluctuations and deep treatment simulated future tidal conditions under rise in sea level. Deep treatment decreased Amax of both species and significant two way interactions between tidal treatments and species were observed. A₄₀₀ was significantly reduced in the deep treatment in B. parviflora but not in A. marina. Carbon dioxide compensation point was not affected by the tidal treatments but varied significantly between both species. The ratio A₄₀₀/A_max was significantly lower in the shallow treatment in B. parviflora indicating higher carbon sink potential at moderate tidal flooding whereas A400/Amax of A. marina was less variable between tidal treatments. Chlorophyll conductance was insensitive to tidal flooding but was significantly higher in B. parviflora than in A. marina. Carbon sequestration of  B. parviflora was substantially reduced in the deep treatment while the difference between tidal treatments was much less in A. marina. These results indicated that these two species responded differently under tidal flooding where A. marina was less sensitive to tidal. Thus, A. marina is better adapted to the projected climate change than B. parviflora.

Keywords: Climate change; inundation; mangroves; seedling growth; water logging

ABSTRAK

Unsur-unsur perubahan iklim seperti kenaikan karbon dioksida atmosfera dan aras air laut sememangnya mempengaruhi ekosistem hutan paya bakau. Dalam kajian ini, propagulAvicennia marina var acutissima dan Bruguiera parviflora didedahkan kepada 2 perlakuan air pasang; dalam dan cetek; selama 6 bulan. Perlakuan cetek mewakili keadaan semasa sementara perlakuan dalam mewakili keadaan kenaikan aras air laut pada masa hadapan. Perlakuan dalam mengurangkan nilai Amax untuk kedua-dua spesis. Nilai A₄₀₀ menurun dengan bererti bagi B. parviflora tetapi tidak A. marina untuk perlakuan dalam. Titik imbangan karbon dioksida tidak dipengaruhi oleh perlakuan air pasang tetapi menunjukkan perbezaan bererti antara kedua-dua spesis. Nisbah A₄₀₀/A_max adalah rendah pada perlakuan cetek B. parviflorayang menandakan potensi sinki karbon yang lebih tinggi manakala nisbah A₄₀₀/A_max bagi A. marina kurang menunujukkan variasi. Konduktans klorofil tidak sensitif terhadap air pasang namun B. parviflora menunjukkan nilai lebih tinggi berbanding A. marina. Sekuestrasi karbon B. parvifloramenurun pada perlakuan dalam tetapi tidak begitu ketara pada A. marina. Kesemua keputusan menunjukkanA. marina lebih toleren terhadap kenaikan aras air laut berbandingB. parviflora.

Kata kunci: Kebanjiran; kegenangan air; paya bakau; pertumbuhan biji benih; perubahan iklim

REFERENCES

Allen, J.A., Krauss, K.W. & Hauff, R.D. 2003. Factors limiting the intertidal distribution of the mangrove species Xylocarpus granatum. Oecologia 135(1): 110-121.

Ball, M.C., Cochrane, M.J. & Rawson, H.M. 1997. Growth and water use of the mangroves Rhizophora apiculata and R. stylosain response to salinity and humidity under ambient and elevated concentrations of atmospheric CO₂. Plant Cell and Environment 20(9): 1158-1166.

Chen, L.Z., Wang, W.Q. & Lin, P. 2005. Photosynthetic and physiological responses of Kandelia candelL. druce seedlings to duration of tidal immersion in artificial seawater. Environmental and Experimental Botany 54(3): 256-266.

Ellison, A.M. & Farnsworth, E.J. 1997. Simulated sea level change alters anatomy, physiology, growth, and reproduction of red mangrove (Rhizophora mangle L.). Oecologia 112(4): 435-446.

Krauss, K.W., Twilley, R.R., Doyle, T.W. & Gardiner, E.S. 2006. Leaf gas exchange characteristics of three neotropical mangrove species in response to varying hydroperiod. Tree Physiology 26(7): 959-968.

Krauss, K.W., Lovelock, C.E., McKee, K.L., López-Hoffman, L.,. Ewe, S.M.L. & Sousa, W.P. 2008. Environmental drivers in mangrove establishment and early development: A review. Aquatic Botany 89(2): 105-127.

McKee, K.L. & Rooth, J.E. 2008. Where temperate meets tropical: Multi-factorial effects of elevated CO2, nitrogen enrichment, and competition on a mangrove-salt Marsh community. Global Change Biology 14(5): 971-984.

McKevlin, M.R., Hook, D.D. & McKee, W.H. Jr. 1995. Growth and nutrient use efficiency of water tupelo seedlings in flooded and well-drained soil. Tree Physiology 15(11): 753-758.

Morison, J.I.L. 1998. Stomatal response to increased CO2 concentration. Journal of Experimental Botany 49 (Special Issue): 443-452.

Naidoo, G. 1983. Effects of flooding on leaf water potential and stomatal resistance in Bruguiera Gymnorrhiza(L.) Lam. New Phytologist93(3): 369-376.

Naidoo, G., Rogalla, H. & von Willert, D. 1997. Gas exchange responses of a mangrove species, Avicennia marina, to waterlogged and drained conditions. Hydrobiologia 352(1): 39-47.

Pezeshki, S.R. 1994. Response of baldcypress seedlings to hypoxia: Leaf protein content, ribulose-1,5-bisphosphate carboxylase/oxygenase activity and photosynthesis. Photosynthetica (Prague) (30): 59-68.

Pezeshki, S.R. 2001. Wetland plant responses to soil flooding. Environmental and Experimental Botany 46(3): 299-312.

Pezeshki, S.R., Pardue, J.H. & DeLaune, R.D. 1996. Leaf gas exchange and growth of flood-tolerant and flood-sensitive tree species to soil oxygen deficiency. Tree Physiology 16: 453-458.

Sayed, O.H. 1995. Effects of the expected rise in sea level on Avicennia marina L: A case study in Qatar. Qatar University Science Journal 15: 91-94.

Skelton, N.J. & Allaway, W.G. 1996. Oxygen and pressure changes measured in situ during flooding in roots of the grey mangrove Avicennia marina (Forssk) Vierh. Aquatic Botany 54(2-3): 165-175.

Taylor, G.E. & Gunderson, C.A. 1998. Physiological site of ethylene effects on carbon dioxide assimilation in Glycine max L. Merr. Plant Physiology 86(1): 85-92.

Urban, O. 2003. Physiological impacts of elevated CO₂ concentration ranging from molecular to whole plant responses. Photosynthetica 41(1): 9-20.

Woodroffe, C.D. & Grindrod, J. 1991. Mangrove biogeography - the role of quaternary environmental and sea-level change. Journal of Biogeography 18(5): 479-492.

Ye, Y., Tam, N.F.Y., Wong, Y.S. & Lu, C.Y. 2004. Does rise in sea level influence propagule establishment, early growth and physiology of Kandelia candeland Bruguiera gymnorrhiza?. Journal of Experimental Marine Biology and Ecology 306(2): 197-215.

*Corresponding author; email: normaniza@um.edu.my