Impact des perturbations anthropiques sur l'évolution du phytoplancton de la lagune de Boughrara, ( tunisie )

Amel  BENREJEB - JENHANI; Mohamed Saleh ROMDHANE

doi:10.71754/instm.bulletin.v29.800

Authors

Amel BENREJEB - JENHANI Université de Carthage. Institut National Agronomique de Tunisie. INAT. Laboratoire Aquaculture et milieu Marine
Mohamed Saleh ROMDHANE Université de Carthage. Institut National Agronomique de Tunisie. INAT. Laboratoire Aquaculture et milieu Marine

DOI:

https://doi.org/10.71754/instm.bulletin.v29.800

Keywords:

Geographical distribution, Eutrophication, Environmental impact, Pollution effects, Man-induced effects, Diatoms, Phytoplankton, Lagoons, Data processing, Dinoflagellates, Toxicity, Biomass, Water quality, Evolution, Algae, Gymnodinium, Gymnodinium of nagasakiense, Bacillariophyceae, Marine, Tunisia, Boughrara Lagoon

Abstract

The deterioration of water quality in Boughrara lagoon, the result of various polluting factors and limited exchanges of water with the sea, severely increased the eutrophication of the environment, resultinging especially in a significant development of micro algae. Analyzing the temporal changes in all phytoplankton groups has shown that periods of high algae biomass are characterized by monospecific development. The growing relative importance of dinoflagellates is shown by a net increase in the dinoflagellates / diatoms ratio. The high development of the Gymnodinium cf nagasakiense species known for its toxicity is more noticeable in summer and winter ( maximum density about 6.10 6 cells per liter ). Spatial data analysis also revealed that some zones were more affected than others by the growth of Gymnodinium in relation to their degree of confinement.