Limnology and Oceanography
Using Ge-68:C-14 dual-labeling, we investigated the absorption efficiency of diatom carbon for the cold water appendicularian Oikopleura vanhoeffeni. The absorption efficiency of bulk carbon (mean = 67%) was not influenced by body size or ingestion rate. For the first time for a pelagic tunicate, food and feces were fractionated into their major biochemical constituents (i.e., low-molecular-weight compounds, lipid, protein, and polysaccharide), allowing calculation of absorption efficiencies for each fraction. Low-molecular-weight compounds and proteins were preferentially absorbed over lipids and polysaccharides. However, predicted C:N ratios of the fecal pellets of O. vanhoeffeni were in the lower range of C:N ratios reported for zooplankton feces. The results are relevant for modeling biogeochemical cycles because pelagic tunicates contribute greatly to vertical particulate organic carbon flux.
Original Publication Citation
Bochdansky, A. B., Deibel, D., & Rivkin, R. B. (1999). Absorption efficiencies and biochemical fractionation of assimilated compounds in the cold water appendicularian Oikopleura vanhoeffeni. Limnology and Oceanography, 44(2), 415-424. doi:10.4319/lo.1999.44.2.0415
Bochdansky, Alexander B.; Deibel, Don; and Rivkin, Richard B., "Absorption Efficiencies and Biochemical Fractionation of Assimilated Compounds in the Cold Water Appendicularian Oikopleura Vanhoeffeni" (1998). OEAS Faculty Publications. 196.