Still-water sinking velocity of fecal material from the pelagic tunicate Dolioletta gegenbauri
- 1 January 1990
- journal article
- research article
- Published by Inter-Research Science Center in Marine Ecology Progress Series
- Vol. 62 (1-2) , 55-60
- https://doi.org/10.3354/meps062055
Abstract
Results of recent models suggest that fecal pellet production by pelagic tunicates should have a major impact on the relative magnitude of export of particulate organic matter from the upper mixed layer of the ocean. However, little is known of the sinking velocities of feces from small salps and doliolids living in continental shelf waters. This study was designed to determine the sinking velocity of fecal pellets from Dolioletta gegenbauri under natural and amended food conditions, and to examine whether sinking behavior is best described by the Stokes or inertial formulations of the force balance equation. Still-water sinking velocity of pellets was determined in the laboratory at 20.degree. C and 36.0.permill. S in a glass cylinder and ranged from 59 to 405 m d-1. Most of the feces produced by specimens fed only naturally occurring particles did not sink. About 70% of the total variance of the logarithm of sinking velocity of the pellets produced by specimens fed the amended diet was explained by a linear regression against the logarithm of pellet volume. These pellets sank more slowly than was expected based on sinking velocities of the pellets of copepods, euphausiids and salps. Also, the rate of increase of sinking velocity with increasing pellet size (which was a linear function of diameter) was lower than predicted by the Stokes equation (i.e. where sinking velocity of spherical particles .varies. diam.2), indicating that the pellets fell in an intermediate zone between the Stokes and inertial forms of the force balance equation.This publication has 11 references indexed in Scilit:
- Role of salps in the flux of organic matter to the bottom of the Ligurian SeaMarine Biology, 1988
- Mass occurrence of Salpa fusiformis in the spring of 1984 off Ireland: implications for sedimentation processesMarine Biology, 1988
- Ecological significance of salp fecal pellets collected by sediment traps in the eastern North PacificMarine Biology, 1986
- Analyses of the settling velocities of fecal pellets from the subtidal polychaete Amphicteis scaphobranchiataJournal of Marine Research, 1985
- Blooms of the pelagic tunicate, Dolioletta gegenbauri: Are they associated with Gulf Stream frontal eddies?Journal of Marine Research, 1985
- Production, composition and sedimentation of salp fecal pellets in oceanic watersMarine Biology, 1982
- Herbivore Diet Affects Fecal Pellet SettlingCanadian Journal of Fisheries and Aquatic Sciences, 1980
- Aggregation of organic matter by pelagic tunicates1Limnology and Oceanography, 1980
- Sinking rates of natural copepod fecal pelletsMarine Biology, 1979
- Sinking rates of fecal pellets from the marine copepod Pontella meadiiMarine Biology, 1977