The lugworm (Arenicola marina) pump:characteristics, modelling and energy cost

Abstract

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 138:149-156 (1996) - doi:10.3354/meps138149 The lugworm (Arenicola marina) pump: characteristics, modelling and energy cost Riisgård HU, Berntsen I, Tarp B The lugworm Arenicola marina was studied in an observation aquarium; the typical undisturbed stroke frequency of the piston pump was ƒ = 6 to 7 strokes min-1. A new experimental setup was used for direct measurement of volume flow at zero and different imposed back pressures. The back pressure characteristic was a nonlinear function, the stroke frequency being reduced with increasing imposed back pressure, attaining a maximal pressure head of 20 cm H2O, which is 30 to 150 times higher than previously found in filter-feeding macro-invertebrate pumps. The back pressure -volume flow characteristic was modelled. At the (assumed) normal operation pressure (5 cm H2O) the power output from the 'standard' (0.5 g dry wt) lugworm pump was calculated to be P p = 12.6 uW. The respiration rate (R, ul O2 h-1) measured in lugworms kept in glass tubes was dependent on the stroke frequency and correlated with dry weight (W, g) according to R = aWb, where a = 344 and b = 0.64 at ƒ = 7 strokes min-1. The total respiration of the 'standard' worm was Rtot = 232 ul O2 h-1 = 1281 uW, and thus the overall pump efficiency was mu = P p/Rtot = 1% which suggests that the energy cost of pumping is modest (&LT5%). The volume of water pumped per ml oxygen consumed was only 0.4 l ml-1 O2 which is &GT100 times lower than values previously found for true filter-feeders. This very low value shows that it is unlikely that the lugworm can live by filter-feeding. Pumping costs . Ventilatory flow rate . Piston stroke frequency . Respiration rate . Filter-feeding Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 138. Publication date: July 25, 1996 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1996 Inter-Research.