Ingestion rates of Daphnia magna Straus (Crustacea: Branchiopoda: Anomopoda) on bacterioplankton and phytoplankton in an aerated waste stabilisation pond
Cauchie, H.-M.; Hoffmann, L.; Thomé, J.-P. (1999). Ingestion rates of Daphnia magna Straus (Crustacea: Branchiopoda: Anomopoda) on bacterioplankton and phytoplankton in an aerated waste stabilisation pond. Belg. J. Zool. 129(1): 285-304 In: Belgian Journal of Zoology. Koninklijke Belgische Vereniging voor Dierkunde = Société royale zoologique de Belgique: Gent. ISSN 0777-6276; e-ISSN 2295-0451, more Also appears in:Mees, J. (Ed.) (1999). Proceedings of the 5th Benelux Congress of Zoology Gent, 6-7 November 1998. Belgian Journal of Zoology, 129(1). Koninklijke Belgische Vereniging voor Dierkunde = Société royale zoologique de Belgique: Brussel. 324 pp., more | |
Authors | | Top | - Cauchie, H.-M.
- Hoffmann, L.
- Thomé, J.-P., more
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Abstract | The impact of zooplankton on waste stabilisation pond (WSP) performance has been poorly studied until now. Zooplankton grazing activity is, however, worth considering as it can control the bacterioplankton and phytoplankton, which are the cornerstone organisms of the WSP treatment technology. The aim of the present study was to determine whether the grazing activity of the dominant zooplankter, Daphnia magna, can significantly control phytoplankton and bacterioplankton in a WSP (Differange, Grand-Duchy of Luxembourg). The biomass of phytoplankton (Bphyto), bacterioplankton (Bbact) and Daphnia magna (BDaphnia) were estimated fortnightly from January to July 1998. At four key moments during this period, the ingestion rates of phytoplankton (IR phyto) and bacterioplankton (IR bact) by D. magma were determined and compared to BPhyto and primarily production (Pprim), and to Bbact and bacterial production (Pbact), respectively. From January to June, IRPhyto varied between 66 and 92% of Bphyto.day-1 and 310% of Pprim, causing a significant drop in Bphyto. The grazing impact of D.magma on bacterioplankton varied between 0.1 and 18% of Bbact.day-1 and between 0.8 and 226% of Pbact. Even when higher than 100% of Pbact, the grazing impact did not lead to a significant decrease of Bbact, because of a significant input of allochtonous bacterial biomass with the influent. |
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