Response of phytoplankton to organic enrichment and shrimp activity in tropical aquaculture ponds : a mesocosm study Lemonnier H. auteur aut IRD Hochard S. auteur aut IRD Nakagawa K. auteur aut IRD Courties C. auteur aut IRD Rodier Martine auteur aut IRD text journalArticle eng text/pdf born digital access We conducted a mesocosm study to investigate the combined effect of organic enrichment and sediment resuspension by shrimp on phytoplankton communities in shrimp aquaculture ponds. Hence, the factorial design included 2 factors: (1) shrimp density with a concomitant increase of feed input, resulting in organic enrichment, and (2) access of shrimp to the sediments. Increasing feed input in the system raised the eutrophication state of the environment, characterized by an increase in phytoplankton biomass. Bioturbation enhanced: (1) mineralization of organic matter via the microbial loop, resulting in faster nutrient recycling, (2) primary production and (3) buffering capacity against eutrophication consequences. The phytoplankton community showed both large temporal variations of its taxonomic composition and resilience to treatments. A shift in species dominance from diatoms + dinoflagellates to green algae was observed in all treatments and coincided with meteorological and N pool changes. Results suggest that algal production was primarily limited by phosphorus and light at low (i.e. low feeding) and high (i.e. high feeding) eutrophication states, respectively. Growth rate of species to be a major factor favoring their dominance in the phytoplankton community in this highly dynamic ecosystem. Consequences for water column management are discussed. specialized Aquaculture Litopenaeus stylirostris Phytoplankton communities Eutrophication Bioturbation NOUVELLE CALEDONIE PACIFIQUE 040 036 Aquatic Microbial Ecology 80 2 105-122 2018 0948-3055 https://www.documentation.ird.fr/hor/fdi:010071371 10.3354/ame01841 0948-3055 [F B010071371] https://www.documentation.ird.fr/hor/fdi:010071371 https://www.documentation.ird.fr/intranet/publi/2017/11/010071371.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2017-12-04 2023-07-11 fdi:010071371 fre