Ventilation and oxygen uptake by three species of Nereis (Annelida: Polychaeta). II. Effects of temperature and salinity changes

Abstract

Ventilation and oxygen uptake of Nereis virens, N. succinea and N. diversicolor were monitored during changing temperatures (5.5 to 37.5 "C) and salinities (1.7 to 24.0 % S). Measurements were performed using a direct flow sensing technique with worms in polyethylene tubes simulating natural conditions. Ventilation amplitude increased with temperature (Qlo = 2.6 to 2.9) for the 3 species, reaching well defined species specific upper limits. This is assumed to be the upper limit for Nereis ventilation capacity. At temperatures above 30 to 35 "C, but below the lethal limit, ventilation decreased and eventually ceased. Oxygen uptake during active periods appeared to increase with temperature over the range measured (Qlo = 1.3 to 2.2). Ventilation requirement showed minimum values at species specific temperatures, suggesting optimum temperatures at the present acclimation level (N. virens, 11 to 20 'C; N. succinea 20 to 35 "C and, N. diversicolor, 5 to 16 " C ) . Reduction in salinity resulted in a decreased ventilation amplitude, possibly due to osmotic swelling of the worms. Oxygen uptake during active periods was quite unaffected by salinity changes. Ventilation requirement increased for all 3 species at low salinities and was most pronounced in the stenohaline N. virens and least in the euryhaline N. diversicolor. The observed responses to temperature and salinity changes are also related to distributional patterns of the 3 species in a Danish estuary.

Surviving in anoxic surroundings: how burrowing aquatic insects create an oxic microhabitat

“…Change in pumping frequency and length with temperature is consistent with results of studies on bioirrigating worms (Seymour 1972, Kristensen 1983c) and larvae (Walshe 1950, Leuchs 1986). However, Leuchs (1986) reported that the increased pumping rate of C. thummi with temperature was the result of a longer pumping duration, and not of increased flow velocity in the burrows as occurred in our study.…”

Effects of temperature on in vitro sediment reworking processes by a gallery biodiffusor, the polychaete Neanthes virens

“…Bioadvective transport by polychaetes is mainly due to water currents induced by dorso-ventral oscillations of the organism (bioirrigation) that destabilize surface particles and carry them to the bottom of the burrow (François et al 2002). Kristensen (1983) also obtained an increase in bioirrigation activities by N. virens at a warm (20°C) temperature that was probably due to an increased demand in oxygen for metabolic activities. The low biodiffusion coefficient could be related to a reduction of food searching activities (Deschênes 2001), of particle storage in the upper part of the burrow (Olivier et al 1996), and/or to a longer bioirrigation period by the worm (Miron et al 1992).…”

“…This thermal sensitivity is likely related to specific adaptations and thermal tolerance. For example, Nereis diversicolor optimum temperatures are low (5 to 16°C) whereas Neanthes virens and N. succinea prefer higher temperatures (11 to 20°C and 20 to 35°C respectively) (Kristensen 1983). Therefore, considering the strong effect of temperature on physiological and metabolic processes, we can predict an important impact on the bioturbation activities of benthic organisms with changes in temperature.…”

“…Therefore, general activities such as feeding, digestion, and locomotion, which influence bioturbation processes, are also affected by temperature (Dobbs 1983, Riisgard & Banta 1998. For example, annelid polychaetes of the genus Nereis, which are widely distributed in coastal areas of Europe and North Amer-ica (Bass & Brafield 1972, Creaser & Clifford 1982, Kristensen 1984, Desrosiers et al 1994, have shown large changes in pumping activity, ventilation, and oxygen uptake (Kristensen 1983, Rissgård et al 1992 as well as in feeding and growth rates (Bass & Brafield 1972, Neuhoff 1979, Creaser & Clifford 1982, Kristensen 1984, Desrosiers et al 1994) after temperature variations. This thermal sensitivity is likely related to specific adaptations and thermal tolerance.…”

Characterization of specificity of bacterial community structure within the burrow environment of the marine polychaete Hediste (Nereis) diversicolor

“…H. diversicolor is active for about 50% of the time with 4.8 min ventilation periods followed by 4.6 min of inactivity at 15 C and at a salinity of 18& (Miron and Kristensen, 1993). Temporal patterns of bioirrigation vary according to several factors, including feeding activity (Kristensen, 2001), sulfide concentration inside burrows (Miron and Kristensen, 1993), temperature and salinity of seawater (Kristensen, 1983).…”