Factors driving the seasonal distribution of planktonic and epiphytic ciliates in a eutrophicated Mediterranean Lagoon

Spatial pattern of ciliates in relation to environmental factors at Sfax south coast (Gulf of Gabes, Tunisia)

“…The Tintinnida Tintinnopsis genus is common in coastal systems (40,41). In the present study, the most abundant species was Tintinnopsisberoidea, this species is quite common in coastal areas and in particular in gulfs (Gulf of Naples, (41)), (Gulf of Tunis, (32)) and (Gulf of Gabes, (9)). This result suggests that T.beroidea (medium-size = 39 µm) performed better than other species probably owing to more flexible adaptive strategies, to particular environmental conditions (wind mixing, light,..) and the shallowness of the water sampling (9).According to Pérez et al(42)the copepods preferentially consume small ciliates.…”

“…Thus, high chlorophyll-a concentration together with an N/P ratio lower than the Redfield ratio indicate that this ecosystem is under pollution pressure (31). Spirotrichea was the predominant class in the south coast of Sfax, which is a common feature in many aquatic ecosystems (3,9,(32)(33)(34). During our study, Tintinnidsac counted for a large proportion (61%) of the ciliate communities.…”

Factors driving the seasonal distribution of zooplankton in a eutrophicated Mediterranean Lagoon

“…Those groups appear accidentally in some samples. For ciliates, sub-samples (25 ml) of planktonic communities taken with a polyvinylchloride (PVC) tube without being filtered were counted under an inverted microscope after fixation with lugol solution (final concentration 1% v/v) and settling for 48 h using the Utermöhl method (1958) (see Dhib et al, 2013). Cell numbers were expressed as cells m À3 .…”

“…Zooplankton signatures may characterize specific hydrographic conditions in most of the world's ecosystems, yet no prior studies have been undertaken in this lagoon regarding the characterization of local zooplankton assemblages nor of their relationship to abiotic and biotic factors. Only phytoplankton, ciliates and macrophytes have been addressed (Dhib et al, 2013(Dhib et al, , 2015. It is therefore essential to study the seasonal succession of zooplankton communities in order to understand the main determining factors governing the biological productivity of the lagoon.…”

“…All these features combine to http://dx.doi.org/10.1016/j.marpolbul.2015.06.012 0025-326X/Ó 2015 Elsevier Ltd. All rights reserved. thus confer upon GML specific functioning properties Dhib et al, 2013).…”