Study on the seaweeds of Ambon Island, Indonesia

Ambon island is located in the Eastern Indonesia at 3°33'-3°43'S, 128°0'-128°16'E. A study to find out the structure of the algae community, based on the transect line method by using quadrate sampling techniques, was conducted in 3 stations (Hutumuri, Lateri and Series). Meanwhile, studies on the diversity of macro algae were carried out in 15 stations all over the Ambon's coastal areas (Galela, Latta, Lateri, Passo, Toisapu, Hutumuri, Rutong, Leahari, Hukurila, Amahusa, Frie, Seilale, Aerlow, Latuhalat and Serie). The results showed that there were 48 species of macro algae belonging to 30 genera, 21 families, 15 orders, 3 classes and 3 divisions. Chlorophyta was represented by Boergesenia forbesi, Bornetella sphaerica, Caulerpa peltata, Chaetomorpha crassa, C. spiralis, Codium edule, C. geppi, Dictyosphaeria cavernosa, D. verssluysii, Enteromorpha clathrata, E, intestinalis, Halimeda opuntia, Neomeris annulata, Ulva conglobata, U. lactuca, U. reticulata, Valonia aegagrophil. Phaeophyta was represented by Padina australis, P. minor, P. tetrastromatica, Sargassum cristaefolium, S. duplicatum, S. polycystum, Turbinaria decurrens, T. ornata. Rhodophyta was represented by Acanthophora muscoides, A. spidfera, Acrocystis nana, Actinotrichia fragilis, Amphiroa foliacea, A. rigida, Ceratodictyon spongiostum, Cryptonemia crenulata, Galaxaura arborea, G. filamentosa, Gelidiella acerosa, Gracilaria arcuata, G. edulis, G. salicornia, G. verrucosa, Halymenia durvillaei, H. boergesenii, Hypnea valentine, Mastophora rosea, Porphyra sp., Rhodymenia sp., Trideocarpa fragilis, and Zellera tawallina. The highest number of species was found in Hutumuri (27 species) and the lowest was in Lateri (2 species). The highest density and relative frequency indices shown by Ulva reticulata (2.82 individuals/m^2; 0.42) were found in Hutumuri. The species similarity values varied from 0-50% with the highest value found in Serie and Hutumuri (C=50%). The highest dominance index (D) was found in Lateri (D=1), and the highest species diversity (H') in Hutumuri (H'=2.86). The species evenness values (E) ranged from 0.849-0.850. The distribution of macro algae species in general showed aggregating pattern.