Interaksi landak laut dan lamun di Pulau Barrang Lompo, Kepulauan Spermonde, Sulawesi Selatan

Abstract

Sea urchin is an active grazer on seagrass. The grazing may have affected on the seagrass bed. The aim of this research was to study the interaction between the sea urchin and seagrass in the Barrang Lompo Island, South Sulawesi. The measurement of the seagrass and the sea urchin density were using a linier quadrant transect method. Correlation between the seagrass and the sea urchin were analyzed using Pearson‟s correlation. The results showed that the highest value of INP (Indeks Nilai Penting) were Thalassia hemprincii (129,39), Enhalus acoroides (88,92), Cyomodecea rotundata (36,10), Halodula uninervis (28,26), Halophila ovalis (9,23) and Syngirodium isoefolium (7,16), respectively. The community of sea urchin was dominated by Tripneustes gratilla (63.69 ind/m2), followed by Diadema setosum (23.10 ind/m2), Echinotrix calamaris (6.10 ind/m2), Echinotrix diadema (2.47 ind/m2), Echinometra matheai (1.33 ind/m2), and Mespilia globulus (1.33 ind/m2). No relationship beetwen seagrass and sea urchin was observed (r= -0.111, P= 0.485) since not all the sea urchin are grazer. Between seagrass on three age stages and sea urchin also showed no significant relationship since the stage pattern of seagrass and its tanin content may not preferred by the sea urchin. The present of T. gratilla and D. setosum as main grazer however showed no significant relationship with the seagrass. D. setosum is food adaptive and T. gratilla utilizes the seagrass leaf as food and protection from wave and predator.