Respiration and nitrogen excretion of neritic zooplankton in relation to potential food supply
Conover, R.J.; Mayzaud, P. (1976). Respiration and nitrogen excretion of neritic zooplankton in relation to potential food supply, in: Persoone, G. et al. (Ed.) Proceedings of the 10th European Symposium on Marine Biology, Ostend, Belgium, Sept. 17-23, 1975: 2. Population dynamics of marine organisms in relation with nutrient cycling in shallow waters. pp. 151-163
In: Persoone, G.; Jaspers, E. (Ed.) (1976). Proceedings of the 10th European Symposium on Marine Biology, Ostend, Belgium, Sept. 17-23, 1975: 2. Population dynamics of marine organisms in relation with nutrient cycling in shallow waters. IZWO/Universa Press: Wetteren. ISBN 90-6281-002-0. 712 pp., meer
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Documenttype: Congresbijdrage
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| Auteurs | | Top |
- Conover, R.J.
- Mayzaud, P., meer
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| Abstract |
A year's survey of zooplankton community metabolism and nitrogen (ammonia) excretion at environmental temperature in Bedford Basin, Nova Scotia, a nearly land-locked fjord, has been carried out. On most experimental dates we also obtained information on the chlorophyll content, total particle volume, using the Coulter Counter, and particulate carbon and nitrogen content from the same depth at the same location from which the experimental zooplankton were collected. Particulate carbohydrate and protein were also measured during the summer of 1974 and during spring bloom of 1975. The zooplankton community was dominated by the neritic copepods Pseudocalanus minutus, Acartia clausi, Remora longicornis or Eurytemora herdmani. Temperature at the depth of collection (experimental temperature) varied from 1 to 16.8 °C. As might be expected, respiration rate was controlled largely by temperature and size of the respiring animals. Regression analysis failed to demonstrate a significant effect on oxygen uptake for any measure of potential food source tested. The O:N atomic ratio was quite uniform over most of the year ranging from 25 to 40 although several periods of depressed values, when the zooplankton appeared to be oxidizing above normal amounts of protein, were observed in the winter months. The O:N ratio was just significantly and positively correlated with chlorophyll but no other measure of potential food supply. Rates of ammonia excretion were strongly correlated with parameters related to the food supply but body size of the animals did not appear to be very important. Particulate nitrogen and carbohydrate apparently had a sparing effect on zooplankton protein, thereby reducing excretion levels, while particulate protein and particles of sizes smaller than 20 µm mean spherical diameter encouraged nitrogen excretion. Several regression equations perhaps suitable for predicting ammonia excretion rates in natural popu- lations of small neritic zooplankton are presented. |
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