Publications des scientifiques de l'IRD

Leruste A., Guilhaumon François, De Wit R., Malet N., Collos Y., Bec B. (2019). Phytoplankton strategies to exploit nutrients in coastal lagoons with different eutrophication status during re-oligotrophication. Aquatic Microbial Ecology, 83 (2), p. 131-146. ISSN 0948-3055.

Titre du document
Phytoplankton strategies to exploit nutrients in coastal lagoons with different eutrophication status during re-oligotrophication
Année de publication
2019
Type de document
Article référencé dans le Web of Science WOS:000487116100003
Auteurs
Leruste A., Guilhaumon François, De Wit R., Malet N., Collos Y., Bec B.
Source
Aquatic Microbial Ecology, 2019, 83 (2), p. 131-146 ISSN 0948-3055
We studied a mesotrophic and a hypertrophic Mediterranean coastal lagoon, both of which had been simultaneously subjected to a nutrient input reduction for 9 yr. We compared these 2 lagoons to an oligotrophic coastal lagoon. Using bioassays comprising 24 h incubations with added phosphorus and/or ammonium, we investigated the response of the phytoplankton communities to nutrient enrichment during summer in terms of biomass, size class structure, abundance and growth. For nitrogen and phosphorus, we identified which nutrient limited phytoplankton growth, and what strategies of nutrient exploitation the communities adopted to cope with these limitations. Ultraphytoplankton dominated the 3 communities, but it differed in composition among the lagoons. Green algae dominated in the hypertrophic lagoon, whereas the mesotrophic lagoon presented a higher diversity of phytoplankton groups. Picocyanobacteria and small diatoms were the most abundant groups in the oligotrophic lagoon, although they accounted for less biomass than green algae. The communities of the mesotrophic and the hypertrophic lagoons strongly responded to the nutrient pulse, showing that the re-oligotrophication trajectories of these lagoons were still very vulnerable to occasional eutrophication events. On the other hand, the oligotrophic lagoon marginally responded to the enrichment, indicating its adaptation to nutrient-depleted conditions. We observed a shift along the eutrophication gradient, from a co-limitation by N and P in the oligotrophic and the mesotrophic lagoons to a single and strong N limitation in the hypertrophic lagoon. Each community demonstrated specific use of internal, external or recycled nutrient pools under experimentally induced limitation.
Plan de classement
Limnologie physique / Océanographie physique [032] ; Limnologie biologique / Océanographie biologique [034]
Description Géographique
MEDITERRANEE
Localisation
Fonds IRD [F B010077017]
Identifiant IRD
fdi:010077017
Contact