Osmotik Word Level Teredo navalis Linnaeus 1758 in the Mangrove Root Habitat in East Halmahera, Indonesia

Abstract

This study aims to analyze the osmotic work level and pattern of osmoregulation at mollusc Teredo navalis Linnaeus 1758 in mangrove root habitats from different salinities. Case study was performed with the purposive sampling method. The research data were analyzed descriptively and quantitatively. The sampling technique is based on tidal conditions of seawater. Two locations was designated, namely station I and II in the north and the south respectively. Teredo navalis samples were taken from 2 types of mangrove roots. Analysis of the level of osmotic work using Automatic Micro Osmometer Roebling Type 13/13 DR. Salinity was measured using a refractometer. The results showed that the osmotic level of Teredo navalis in the root habitat of Rhizophora sp. and Avicennia sp. at high and low tide conditions varied, specifically 523 mOsm/l H2O, 123 mOsm/l H2O, and 32 mOsm/l H2O. This varying level of osmotic action results in three patterns of osmoregulation, viz. hyperosmotic, hypoosmotic, and isosmotic. The highest salinity was found in Avicennia sp. mangrove at station II and the lowest in Rhizophora sp. at low tide at station II, with the value was 31‰ and 10‰ respectively. Differences in salinity determine the osmoregulation pattern of Teredo navalis L in different habitats.