Metabolic activities of meiofaunal communities in a semi-enclosed lagoon: possibilities of trophic competition between meiofauna and mugilid fish
Lasserre, P.; Renaud-Mornant, J.; Castel, J. (1976). Metabolic activities of meiofaunal communities in a semi-enclosed lagoon: possibilities of trophic competition between meiofauna and mugilid fish, 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. 393-414 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. European Marine Biology Symposia, 10(2). IZWO/Universa Press: Wetteren. ISBN 90-6281-002-0. 712 pp., more In: European Marine Biology Symposia., more |
| Available in | Authors | | Document type: Conference paper
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| Authors | | Top | - Lasserre, P., more
- Renaud-Mornant, J.
- Castel, J.
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| Abstract | The semi-enclosed fish reservoirs of the Bassin d' Arcachon, France, constitute mixohaline lagoons, where the rich input of detritus plays a prominent role in the food chain. Spring and summer growth retardation of the grey mullets herded in the reservoirs are explained in terms of a trophic competition between meiofauna and this mugilid fish, both feeding on detritus. Very high meiofaunal biomass paralleled the high numerical abundance. A significant percentage of the total community respiration was contributed by the meiofauna. Total community respiration ranged from 29.3-107.9 ml O2/m².hr and was positively correlated with temperature increase. In the reservoirs, meiofaunal respiration ranged from 9-58.4 % of the total community respiration, with values of 8.6 and 63.0 ml O2/ m².hr respectively. In the intertidal station, outside the reservoirs, the respiration of meiofauna was only 4-14% of the total, with values of 1.2 and 11.4 ml O2/m².hr respectively. Meiofauna was metabolically most important in July, when nematodes, harpacticoid copepods, ciliates, oligochaetes, turbellarians and polychaetes increased in abundance and biomass. It was established that a significant part of the detritus, accumulated from late autumn through winter, is rapidly decomposed in spring and summer. This material provides an abundant food source on which luxurious development of meiofauna occurs. Significant amounts of detritus can therefore be lost by way of the meiofauna community through its high metabolic activity. |
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