|Detrital utilization by the polychaete Capitella capitata|
Tenore, K.R. (1975). Detrital utilization by the polychaete Capitella capitata. J. Mar. Res. 33(3): 261-274
In: Journal of Marine Research. Sears Foundation for Marine Research, Yale University: New Haven, Conn.. ISSN 0022-2402, more
Although organic detritus is an important energy source in marine ecosystems little quantitative data are available on rates of utilization by deposit feeders. A major reason is the difficulty of using isotope tracer techniques due to the release and recycling of such non- conservative labels as C-14 from the detritus during suspension in an aquatic medium. The effect of initial particle size (0.18 to 2 mm) and 'aging' (0 to 54 days) of detritus derived from eel grass Zostera marina on net incorporation by the polychaete, C.capitata was investigated using isotope tracer techniques with controls to account for errors due to leaching of C-14. There was an increase in the rate of net incorporation with increasing age of the detritus of all the different particle sizes. However, for the first 2 periods of aging (0 and 11 days) there was a greater incorporation of the finest size detritus but with subsequent aging there was greater net incorporation of detritus with larger particle size. Decay experiments with detritus derived from eel grass showed an initial rapid decrease then a slower rate of increase in nitrogen content and corresponding changes in C:N ratios. The observed differences illustrate the need for considering the qualitative state of detritus used in growth experiments. Also the long decay time associated with sea- grasses versus shorter decay periods of detritus from other sources would prolong the availability of the detrital food resource by expanding the temporal period of utilization of the total detrital pool.