Metabolic responses to changing environmental conditions in the brackish water polychaetes Marenzelleria viridis and Hediste diversicolor

摘要: The metabolic strategies of the polychaete Marenzelleria viridis (Verrill 1873), a successful immigrant into Baltic shallow eutrophic coastal waters with meso-to oligohaline salinities since 1980's, were determined by simultaneous calorimetry and respirometry. Resistance to oxygen deficiency under varying ecological conditions was also examined. results studies this compared those common indigeneous Nereis (Hediste) diversicolor (O.F. Muller). At 10 20 °C average habitat salinity 5‰ M. gradually reduced its activity declining partial preessures (pO2), whereas H. maintained activity. metabolism both species remained fully aerobic down pO2 2 kPa. An additional hyposmotic stress 0.5‰ at temperature led decrease in rate consumption below kPa, heat dissipation constant. viridis, however, further both, consumption. rates anoxia similar, amounting ca. 20% normoxic rate. resistance two ranging between 21 290 h (median survival time LT50), depending on salinity. Specimens used present study collected from Southern inlet “Dars-Zingster-Boddenkette” during 1992 1993.