Plankton community dynamics in a subtropical lagoonal system and related factors

Abstract

Changes of the plankton community in a shallow, subtropical lagoonal system and its relation to environmental conditions were investigated during an annual cycle to provide information on its spatial and seasonal variation pattern. The study carried out at four sites (three in the Peixe lagoon and one in the Ruivo lagoon), which are located in the Lagoa do Peixe National Park, southern Brazil. The system has a temporary connection to the Atlantic Ocean by a narrow channel. The phytoplankton density was higher in the Peixe lagoon whereas the specifi c richness was higher in the Ruivo lagoon which is also a site with the lower salinity. The phytoplankton biomass near the channel showed seasonal variation with the highest value in fall and lowest in winter. Zooplankton richness was inversely correlated with salinity, and had the highest values in the Ruivo lagoon. Ordination analysis indicated seasonal and spatial patterns in plankton community in this lagoonal system, related to variation in salinity. In addition, the wind action and precipitation were important factors on the spatial and seasonal salinity changes in the lagoon with direct infl uence on the plankton community dynamics.

Subtropical Coastal Lagoon from Southern Brazil: Environmental Conditions and Phytobenthic Community Structure

“…The species Cocconeis sawensis was recorded at the southern benthos of the lagoon, and it was also observed in the plankton and epiphyton in association with the macroalgae Cladophora sp. in the fall and winter seasons [33,46]. This suggests that in shallow environments, the plankton receives a greater contribution of benthic species than the opposite.…”

“…Seasonally, salinity has the highest values in summer and the lowest in winter. These low values can be attributed to the action of the wind, predominantly northeast, that propelled the waters from the Ruivo Lake which are less saline, to the Peixe Lagoon [33]. In the summer, the decrease of the precipitation and intensity of the wind causes the outstanding increase of the salinity.…”

“…So far, most studies concentrated on phytoplankton at Patos Lagoon [17][18][19][20][21][22][23][24], Tramandaí-Armazém Lagoon [25][26][27][28][29], and Peixe Lagoon [30][31][32][33][34]. Regarding microphytobenthic, studies were limited to salt marshes and to the Patos Lagoon estuary [35][36][37][38][39][40][41][42][43].…”

“…Studies about phytoplankton in subtropical coastal lagoon from south of Brazil showed that the structure and dynamic of the phytoplanktonic community were regulated by hydrological factors (inflow-outflow of continental and coastal waters in the system) as well as by meteorological conditions (wind and rainfall) and limnological variables (temperature and salinity) [18,19,33]. We have a set of factors that can act simultaneously while being difficult to recognize a main factor.…”

Dynamique Des Eléments Nutritifs Et Du Phytoplancton Dans Le Barrage Béni Haroun Dans l’Est Algérien

“…Cette dynamique est suivie par une variation très hautement significative (p <0,01) de la quantité de biomasse phytoplanctonique (Tab.3). Cela explique bien que la structure de la communauté phytoplanctonique réagit fortement aux variables abiotiques, selon les préférences écologiques (Donadel et al, 2016 ;Bellinger et Sigee, 2010). La composition et l'abondance des espèces de plancton sont fonction des interactions avec les conditions environnementales, notamment la salinité, la température, la lumière et les éléments nutritifs (Mukherjee et al, 2010).…”