Effects of Epiphyte Density on Seagrass Leaf Turnover Rate
Maria Luisa S. Orbita*1 and Hiroshi Mukai2
1Mindanao State University-Iligan Institute of Technology
Andres Bonifacio Avenue, Tibanga, Iligan City
2Field Science Center for Northern Biosphere, Akkeshi Marine Station
Hokkaido University, 5 Aikappu, Akkeshi-cho, Akkeshi-gun, Hokkaido, Japan
An experimental investigation on the effects of epiphyte density on leaf turnover rate was carried out on four temperate seagrass species: Zostera japonica, Zostera marina, Zostera asiatica, and Phyllospadix iwatensis. The four seagrass species were cultured in outdoor tanks under ambient conditions and leaf turnover rates were measured with the presence and absence of epiphytes. The leaf turnover rates of Z. japonica, Z. asiatica, and Z. marina when epiphytes were removed were significantly lower, but the same seagrass species exhibited faster leaf turnover rates under the control condition. The leaf turnover rate of Z. japonica, Z. marina, and Z. asiatica within the control and experimental conditions was significantly affected by the changes in the epiphyte density, while no significant effect was detected in P. iwatensis. This study shows that high epiphyte density enhanced high leaf turnover rates exhibited by Zostera species, as the adaptive mechanism against epiphytism.
Seagrass meadows have been considered as one of the most productive of the marine ecosystems, contributing significantly to the productivity of shallow coastal areas of both temperate and tropical waters (McRoy & McMillan 1977; Zieman & Wetzel 1980). Seagrass epiphytes are an important component of these highly productive ecosystems, often contributing greater than one-third to the total above ground biomass (Penhale 1977; Heijs 1984; Tomasko & Lapointe 1991) and as much as 30% to the combined seagrass/epiphyte productivity (Penhale 1977; Morgan & Kitting 1984; Heijs 1984, 1985, 1987).
ARAN EJ, COLLINS GB. 1992. In vitro determination of chlorophylla and pheophytin a in marine and freshwater phytoplankton by fluorescence. USEPA Method 445.0. Version 1.1.
BOROWITZKA MA, LETHBRIDGE RC. 1989. Seagrass epiphytes. In: Seagrasses: a treatise on seagrasses with special reference to the Australian region. LARKUM AWD, McCOMB AJ and SHEPHERD SA ed. Amsterdam: Elsevier. p. 304-345.
BOROWITZKA MA, VESK M. 1978. Ultrastructure of the Corallinaceae (Rhodophyta). I. The vegetative cells of Corallina officinalis and C. cuvierii. Mar Biol 46: 295.
BORUM J, KAAS H and WIUM-ANDERSEN S. 1984. Biomass variation and autotrophic production of an epiphyte-macrophyte community in a coastal Danish area. 2. Epiphyte species composition, biomass and production. Ophelia 23: 165.
BRUSH, MJ, NIXON SW. 2002. Direct measurements of light attenuation by epiphytes on eelgrass Zostera marina. Mar Ecol Prog Ser 238: 73.
DALLA VIA J, STURMBAUER C, SCHÖWEGER E, SÖTZ M, MATHEKOWITSCH STIFTER, REIGER R. 1998. Light gradients and meadow structure in Posidonia oceanica: ecomorphological and functional correlates. Mar Ecol Prog Ser 163: 267.
GRANGER SL, TRABER MS, NIXON SW. 2000. Propagation of Zostera marina L. from seed. In: Seas at the millennium: an environmental evaluation. SHEPPARD C ed. Oxford: Elsevier. p. 55-58.
HEIJS FML. 1984. Annual biomass and production of epiphytes in three monospecific seagrass communities of Thalassia hemprichii (Ehrenb.) Aschers. Aquat Bot 20: 195.
HEIJS FML. 1985. Some structural and functional aspects of the epiphytic component of four seagrass species (Cymodocea oceoideae). Aquat Bot 23: 225.
HEIJS FML. 1987. Qualitative and quantitative aspects of the epiphytic component in a mixed seagrass meadow from Papua New Guinea. Aquat Bot 27: 363.
HEMMINGA MA, DUARTE CM. 2000. Seagrass Ecology. Cambridge University Press. p. 99-138.
JACOBS RPMW, HERMELINK PM, VN GEEL J. 1983. Epiphytic algae on eelgrass at Roscoff, France. Aquat Bot 15: 157.
KENDRICK GA, LAVERY PS. 2001. Assessing biomass, assemblage structure and productivity of algal epiphytes on seagrasses. In: Global seagrass research methods.
SHORT FT, COLES RG ed. Amsterdam: Elsevier p. 199-253.
LOSEE RF, WETZEL RG. 1983. Selective light attenuation by the periphyton complex. In: Periphyton of freshwater ecosystems. Wetzel RG, Junk W, ed. p. 89-96.
McROY CP, McMILLAN C. 1977. Production, ecology and physiology of seagrasses. In: Seagrass Ecosystems: A Scientific Perspective.
McROY CP, HELFFERICH C ed. New York: Marcel Dekker. p. 53-88.
MORGAN MD, KITTING CL. 1984. Production and utilization of the seagrass Halodule wrightii and its attached epiphytes. Limnol Oceanogr 29: 1076.
MOSS B. 1982. The control of epiphytes by Halydris siliquosa (L.) Lyngb. (Phaeophyta, Cystoseiraceae). Phycol 21: 191.
MUKAI H. 1990. Macrophyte-phytal organism interactions. In: Introduction to Applied Phycology. AKATSUKA I ed. The Hague: SPB Academic Publishing: p. 347-365.
PENHALE PA. 1977. Macrophyte-epiphyte biomass and productivity in an eelgrass Zostera marina L. community. J Exp Mar Biol Ecol 26: 211.
PETERSON BJ, FRANKOVICH TA, ZIEMAN JC. 2007. Response of seagrass epiphyte loading to field manipulations of fertilization gastropod grazing and leaf turnover rates. J Exp Mar Biol Ecol 349: 61-72.
SAND-JENSEN KJ . 1975. Biomass, net production and growth dynamics in an eelgrass (Zostera marina L.) population in Vellerup Vig, Denmark. Ophelia 14: 185-201.
SAND-JENSEN KJ. 1977. Effect of epiphytes on eelgrass photosynthesis. Aquat Bot 3: 55.
SAND-JENSEN KJ, REYSBECH NP, JORGENSEN BB. 1985. Microprofiles in epiphytic communities on submerged macrophytes. Mar Biol 89: 55.
SASIL-ORBITA ML. 2006. Effects of aging on the photosynthetic activity and life history strategy in temperate seagrasses. [PhD dissertation]. Hokkaido, Japan: Hokkaido University. 105p. (available at Hokkaido University)
SHORT FT, DUARTE CM. 2001. Methods for the measurements of seagrass growth and production. In: SHORT FT and COLES RG ed. Amsterdam: Elsevier Science: p. 155-182.
TOMASKO DA, LAPOINTE BE. 1991. Productivity and biomass of Thalassia testudinum as related to water column nutrient availability and epiphyte levels: field observations and experimental studies. Mar Ecol Prog Ser 75: 9.
VAN MONTFRANS J, WETZEL RL, ORTH RJ. 1984. Epiphyte-grazer relationships in seagrass meadows: consequences for seagrass growth and production. Estuary 7: 289.
ZIEMANN JC, WETZEL RG 1980. Methods and rates of productivity in seagrasses. In: PHILLIPS RC and McROY CP ed. Handbook of seagrass biology. New York: Garland STMP. p. 87-116.