Phenological observations on Posidonia oceanica (L.) Delile medows along the coast of Akkum (Sıgacık Bay, Aegean Sea, Turkey)

Öz

Abstract Phenological observations were carried out on Posidonia oceanica meadows between December 1994 and April 1995 along the coast of Akkum (Sıgacık Bay, Aegean Sea, Turkey) from two shallow depths (1-3 m; 4-7 m). The highest flowering density of 136 inflorescence / m2 was observed in the 4-7 m depth during January 1995. Inflorescences more often occured on the orthotropic rhizomes in the dense beds. Inflorescence mostly bore 2 rarely 1 or 3 spikes, distichous with 2-3 flowers with a male flower and a sterile extension at the apex. Fruits started maturing in February and got mature during April. Plants at the 4-7 m depth produced 15 mature fruits from a total of 19 flowers in seven inflorescences. Shoot density was found to be maximum (880 shoots / m2) during December, with 7420 leaves / m2), at the 4-7 m depth. The leaf lengths of the plants at the 4-7 m depth gradually increased from December to April. Phenological differences between the two depths were mainly due to the fact that the plants in the sparse and isolated meadows in the shallower areas had short and even falciform leaves, compared to the ones in the deeper and central areas.

Anahtar Kelimeler

• Key words: Seagrass, Posidonia oceanica, phenology, the Aegean Sea, Turkey.

Kaynakça

1. Boudouresque, C.F., Meinesz A. and Pergent, G. (1983). Mesure de la Production annualle de Rhizomes dans l’Herbier a Posidonia oceanica, A Port-cros (Var) et Galeria (Corse). Rapp. Comm. Int. Mer. Medit. 28: 135-136.
2. Boudouresque, C.F. and Thelin, I. (1985). Floraison et Fructification de Posidonia oceanica: un protocole d’etude standardise. Rapp. Comm. int. Mer. Medit. 29: 5.
3. Buia, M.C., Zupo, V. And Mazzella, L. (1992). Primary production and growth dynamics in Posidonia oceanica. P.S.Z.N.I: Marine Ecology 13: 2-16.
4. Caye, G. (1980). Analyse du polymorphisme caulinaire chez Posidonia oceanica (L.) Delile. Bull. Soc. Bot. Fr. 127: 257-262.
5. Caye, G. and Meinesz, A. (1984). Observations sur la Floraison et la Fructification de Posidonia oceanica dans la baie de Vıllefranche et en corse du sud. In: C.F., Boudouresque, A. Jeudy de Grissac and J.Olivier (Editors), Int. Workshop Posidonia oceanica beds, Gis Posidonie Publ., Fr., 1: 193-201.
6. Den Hartog, C. (1970). The Seagrasses of the World. North Holland Publishing Company, Amsterdam, 275 pp. 31 plates.
7. Giraud, G. (1976). Floraison de Posidonia oceanica A Port-Cros. Trav. Sci. Parc nation, Port-Cros, 2, 191-193.
8. Giraud, G. (1977a). Recensement des floraisons de Posidonia oceanica (L.) Delile en Méditerranée. Rapp. Comm. Internation. Mer. Médit. Monaco 24: 126-130.

9. Giraud, G. (1977b). Contribution a la description et a la phénologie quantitative des herbiers de Posidonia oceanica (L.) Delile. Thése doctorat, Univ. Aix-Marseille 2, France, 150 pp.
10. Giraud, G. (1977c), Essai de classement des herbiers de Posidonia oceanica (L.) Delile. Bot. Mar. 20: 487-491.
11. Mazzella, L., Gambi, M.C., Russo, G.F. and Buia, M.C. (1984). Deep flowering and fruiting of Posidonia oceanica beds around the Island of Ischia (Gulf of Naples). In: C.F., Boudouresque, A. Jeudy de Grissac and J.Olivier (Editors), Int. Workshop Posidonia oceanica beds, Gis Posidonie Publ., Fr., 1, 203-209.
12. Pergent, G. and Pergent, C. (1984). Floraison de Posidonia oceanica (Linnaeus) Delile dans le Golfe d’Izmir (Turquie). E.Ü. Fac. Sci. Journ. 7: 19-24.
13. Pergent, G., Maiz, B.N., Boudouresque, C.F. and Meinesz, A. (1989). The flowering of Posidonia oceanica over the past fifty years: Lepidochronological study. In: C.F., Boudouresque, Meinesz, A., Fresi, E. and Gravez, V. (Editors). Int. Workshop on Posidonia Beds. Gis. Posidonie Publ., Fr., 2: 69-76.
14. Pergent, G., Raimondino, V.R. and Pergent, G. (1994). Primary production of Posidonia oceanica in the Mediterranean Basin. Marine Biology, 120: 9-15.
15. Pergent, G., Pergent-Martini, C. and Boudouresque, C.F. (1995). Utilisation de l’Herbier à Posidonia oceanica comme Indicateur Biologique de la Qualité du Milieu Littoral en Mediterranée: Etat des Connaissances. Mesogee, 54: 3-27.
16. Thelin ,I., Boudouresque, C.F. (1985). Posidonia oceanica Flowering and Fruiting recent 4 data from an International inquiry. Posidonia Newsletter, 1: 5-14.