PERSONAL DE APOYO
UIBRIG RomÁn Armando
artículos
Título:
Mixotrophic ciliate dynamics in two zones of a temperate and highly turbid estuary in South America, Argentina
Autor/es:
PETTIGROSSO, ROSA E.; GARCÍA, MAXIMILIANO; UIBRIG, ROMÁN; DUTTO M.S; MARÍA LÓPEZ MORALES; HOFFMEYER, MÓNICA S.
Revista:
ECOLOGÍA AUSTRAL
Editorial:
ASOCIACIÓN ARGENTINA DE ECOLOGÍA
Referencias:
Lugar: Buenos Aires; Año: 2016 vol. 26 p. 107 - 119
ISSN:
0327-5477
Resumen:
Mixotrophy is a feeding strategy by which some organisms combine autrotrophic and heterotrophicactivities. The seasonal dynamics of the five most common mixotrophic ciliates were studied monthly insurface layers of the inner and middle zone of the Bahía Blanca estuary, a nutrient-rich, shallow and highlyturbid environment in Argentina, from January to December 2009. Temperature, salinity, turbidity andchlorophyll a were recorded, as well as the abundance and biomass of Strombidium capitatum, Strombidiumacutum, Cyrtostrombidium sp., Lohmanniella oviformis and Tontonia appendiculariformis. The highest mixotrophicciliate abundance was recorded during the austral winter (June-July) in the inner zone, meanwhile in themiddle zone of the estuary the presence of these ciliates was almost null. The highest chlorophyll contributionderived from mixotrophic ciliates to total chlorophyll a ranged from 6% in the inner zone to 23% in the middlezone, both registered in autumn. The low abundance of mixotrophs in the middle zone of the estuary duringthe winter, as is usually observed in other coastal ecosystems, could be explained through a higher grazingpressure in this zone (top-down control) by mesozooplankton (e.g., copepods) in comparison to the inner zone.The secondary bloom of phytoplankton consistently observed during the last summers dominated by smallsized diatoms and nanoplankton phytoflagelates, could have sustained the high abundance of mixotrophicciliates registered in the middle zone in autumn and summer.