A. Migne et D. Davoult, AMMONIUM EXCRETION IN 2 BENTHIC CNIDARIANS - ALCYONIUM-DIGITATUM (LINNAEUS, 1758) AND URTICINA-FELINA (LINNAEUS, 1767), Journal of sea research, 37(1-2), 1997, pp. 101-107
As part of an evaluation of nitrogen fluxes between the water column a
nd a macrobenthic community of the Strait of Dover (eastern English Ch
annel), ammonium excretion was measured throughout the year in two com
mon cnidarians (the octocoral Alcyonium digitatum and the sea anemone
Urticina felina) which together accounted for 37% of the biomass. Mean
ammonium excretion rates were 6.48 (+/-2.44 s.d.) mu g N g(-1) h(-1)
(ash-free dry weight) for A. digitatum and 4.12 (+/-1.38 s.d.) mu g N
g(-1) h(-1) for U. felina. Seasonal variations were observed in the ex
cretion of A. digitatum, whereas such variations were less pronounced
in U. felina. These trends are discussed in relation to temperature, f
ood availability, nutritional state and nutritional habits of the two
species. The results of this and a previous study indicate a nitrogen
production of 18.9 g N m(-2) y(-1) for the entire benthic community.