A mathematical model of the
interactions in the mixed culture of invertebrates and algae in the “producer–consumer”
aquatic biotic cycle
T.I. Pisman, O.N.
Bogdanova-2004
Aquatic Ecology, 38(3): 415-423
Abstract:
This paper presents a mathematical model of
interactions between two herbivorous invertebrates (ciliate Paramecium
caudatum and rotifer Brachionus plicatilis) and two planktonic
algae (Chlorella vulgaris and Scenedesmus quadricauda)
spatially segregated in two compartments of a chemostat–type
experimental microcosm system. The model mimics a “producer–consumer”
aquatic biotic cycle, describing the dynamics of the mixed culture of ciliates
and rotifers, as “consumer”
compartment, feeding on the mixed algal culture, as “producer”
compartment, under N-limiting conditions. We experimentally found that
metabolites of the alga Scenedesmus produce an adverse effect on the
reproduction of ciliate Paramecium. Taking this effect into account
improved the behavior of the model, the results of which came into qualitative
agreement with the experimental results. Both our experimental and modeling
approaches demonstrated that, even in conditions of a spatially–segregated
“producer-consumer”
biotic cycle, species coexistence is impossible either in the mixed algal
culture or in the mixed invertebrate culture. Scenedesmus excluded Chlorella,
whereas Brachionus excluded Paramecium.
(Institute of Biophysics SB RAS,
Akademgorodok, Krasnoyarsk 660036, Russia, e-mail: pech@ibp.ru)