INVESTIGADORES
FERMANI Paulina
artículos
Título:
The dynamics of picocyanobacteria from a hypereutrophic shallow lake is affected by light-climate and small-bodied zooplankton: a ten-year cytometric time-series analysis
Autor/es:
QUIROGA, MV; HUBER P; OSPINA-SERNA J; DIOVISALVI N.; ODRIOZOLA M; CUETO G; LAGOMARSINO L.; FERMANI P; BUSTINGORRY J.F; ESCARAY, R.; ZAGARESE H.; UNREIN F.
Revista:
FEMS MICROBIOLOGY ECOLOGY
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Lugar: Londres; Año: 2021 vol. 97
ISSN:
0168-6496
Resumen:
In aquatic systems, an interplay between bottom-up and top-down processes determines the dynamic of picocyanobacteria (Pcy) abundance and community structure. Here, we analyzed a long-term time series (sampled fortnightly, 2007-2017) from a hypereutrophic turbid shallow lake located within the Pampa Region of South America, generating the first long-term record of freshwater Pcy from the Southern Hemisphere. We used a cytometric approach to study Pcy community, and focused on its relations with nutrient and light conditions (bottom-up) and potential grazers (top-down). This study revealed a novel Pcy abundance seasonality with winter maximums, related with decreased predation pressure by seasonal rotifers during colder seasons. The cytometric signal of Pcy detected different top-down effects of zooplankton over this community. Strong predation exerted by rotifers during summer appears to increase Pcy cytometric alpha diversity. On the other hand, a direct effect of the non-seasonal small cladocerans Bosmina spp. decreased Pcy abundance and induced a shift from single-cell Pcy into aggregated forms. This structuring effect of Bosmina spp. was further confirmed by Pcy cytometric (dis)similarity analyses from the time series and in situ experimental data. Remarkably, Pcy showed acclimatization to underwater light variations, resembling the relevance of light in this turbid system.