Mesozooplankton Structure and Seasonal Dynamics in Three Coastal Systems of Argentina: Bahía Blanca Estuary, Pirámide Bay, and Ushuaia Bay

BERASATEGUI, A.; LÓPEZ ABBATE, M. C.; D'AGOSTINO, VALERIA C.; PRESTA, M. L.; UIBRIG, R.; GARCÍA, T. M.; NAHUELHUAL, E.; CHAZARRETA, C. J.; DUTTO, M. S.; GARCIA, M.; CAPITANIO, F.; HOFFMEYER, M. S.

Plankton Ecology of the Southwestern Atlantic

Springer International Publishing

Año: 2018; p. 327 - 347

Mesozooplankton communities in coastal ecosystems have successfullyadapted to a wide range of environments. However, the current rate of coastalmodification is challenging the survival of resident species. In this chapter, wedescribe the structure and annual dynamics of the mesozooplankton communityin recent years for three coastal systems in Argentina that are subject to humandisturbance: (1) Bahía Blanca Estuary, (2) Pirámide Bay in Nuevo Gulf and (3)Ushuaia Bay in the Beagle Channel. The seasonal dynamics of mesozooplanktonabundance in Bahía Blanca Estuary during 2009?2010 exhibited a unimodalpattern with an increase during the warm seasons, while organism abundanceincreased linearly with both salinity and turbidity. In Nuevo Gulf, researchon the seasonal dynamics of mesozooplankton conducted during 2014?2015exhibited a bimodal abundance pattern with peaks in late summer and spring.No significant relationships between mesozooplankton and the environmentalvariables included in Nuevo Gulf were found. The seasonal dynamics ofmesozooplankton in Ushuaia Bay in the years 2006?2008 exhibited a bimodalabundance pattern with peaks in summer and early autumn; this pattern wasmainly driven by the concentration of chlorophyll a. In Bahía Blanca Estuary,a gradual decrease in species richness was observed throughout the last fourdecades, while changes in species composition were also observed, suggestingthat some species have the ability to acclimate to higher salinity and turbidityas well as to pollution. In Nuevo Gulf, the mesozooplankton communityshowed no significant modifications over time, which may be related to thelow anthropogenic pressure. Although no profound shifts in mesozooplanktonwere observed in Ushuaia Bay, eutrophication may have an impact in the futurethrough its effect on primary producers.