title: About the interest of a zooplankton compartment in pond systems: methodology to study the growth kinetic of Daphnia pulex on Scenedesmus sp.
abstract: A reliable characterization of cladocerans' growth kinetic on their substrates is crucial for the estimation of their biochemical conversion rate in pond models. Although many studies reported cladocerans' growth inhibitions by high chlorophyceae contents, their growth kinetics had continued to be described in many pond system models by Monod-type kinetic, which describes growth saturation by high substrate contents, but fails to explain the disappearance of cladocerans observed during chlorophyceae's bloom periods. This study aimed to develop a methodology and assess whether growth-inhibition-type models used to describe microbial growth kinetics can be applicable to cladocerans. Experiments were carried out using Daphnia pulex populations and Scenedesmus sp. First, biomass of D. pulex was measured through digital image processing (DIP) during growth experiments. Then, three candidate models (i.e., Andrews, Edward and Haldane models), along with the Monod model, were fitted to the observed data and compared. The results showed that the DIP technique provided reliable results for estimating the biomass of D. pulex. Our findings show that the candidate growth inhibition-type models satisfactorily described D. pulex's growth kinetic (86% variance accounted for). Scenesdemus sp. were not strong inhibitors of the growth of D. pulex (high inhibition constant and low half-saturation constant found).
authors.affiliation: Unité: Assainissement et Environnement, Département Sciences et Gestion de l'Environnement, Université de Liège, Avenue de Longwy, 185-B 6700 Arlon, Belgium E-mail: nliady@yahoo.fr; Unité de recherche sur les zones humides, Département de Zoologie, Université d'Abomey-Calavi, 01 B.P. 526 Cotonou, Benin.
authors.forename: M N D
authors.initials: MN
authors.lastname: Liady
authors.affiliation: Unité: Assainissement et Environnement, Département Sciences et Gestion de l'Environnement, Université de Liège, Avenue de Longwy, 185-B 6700 Arlon, Belgium E-mail: nliady@yahoo.fr; Université de Kinshasa, Département de l'Environnement et de Chimie, Laboratoire d'Écotoxicologie, Management de la Qualité de l'Eau et Biotechnologie Environnementale, BP 190, Kinshasa XI, R. D. Congo.
authors.forename: T T
authors.initials: TT
authors.lastname: Tangou
authors.affiliation: Unité de recherche sur les zones humides, Département de Zoologie, Université d'Abomey-Calavi, 01 B.P. 526 Cotonou, Benin.
authors.forename: E D
authors.initials: ED
authors.lastname: Fiogbe
authors.affiliation: Centre de Recherche Public Gabriel-Lippmann, 41, rue du Brill, L-4422 Belvaux, Luxembourg.
authors.forename: H-M
authors.initials: HM
authors.lastname: Cauchie
authors.affiliation: Unité: Assainissement et Environnement, Département Sciences et Gestion de l'Environnement, Université de Liège, Avenue de Longwy, 185-B 6700 Arlon, Belgium E-mail: nliady@yahoo.fr.
authors.forename: J-L
authors.initials: JL
authors.lastname: Vasel
mesh_terms: D000818:Animals; D018533:Biomass; D003621:Daphnia / Q000254:growth & development*; D017753:Ecosystem; D007700:Kinetics; D061005:Ponds / Q000737:chemistry*; D044444:Scenedesmus / Q000254:growth & development*; D015048:Zooplankton / Q000254:growth & development*