Impacts of an uncontrolled phosphogypsum dumpsite on summer distribution of phytoplankton, copepods and ciliates in relation to abiotic variables along the near-shore of the southwestern Mediterranean coast

• Published in: Marine pollution bulletin 2012-02, Vol.64 (2), p.336-346
• Main Authors: Rekik, Amira, Drira, Zaher, Guermazi, Wassim, Elloumi, Jannet, Maalej, Sami, Aleya, Lotfi, Ayadi, Habib
• Format: Article
• Language: English
• Subjects: Animals; Bacillariophyceae; Biodiversity; Calcium Sulfate - analysis; Ciliates; Ciliophora; Ciliophora - physiology; coastal water; coasts; Copepoda; Copepoda - physiology; Crustacea - physiology; Crustacean zooplankton; Ecosystem; Environmental Monitoring; humans; Mediterranean Sea; North coast of Sfax; nutrients; Phosphogypsum; Phosphorus - analysis; Physico-chemical parameters; Phytoplankton; Phytoplankton - physiology; Salinity; Seasons; Seawater - analysis; Seawater - chemistry; summer; Temperature; water pollution; zooplankton; Zooplankton - physiology
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2011.11.005

► We examine the impacts of phosphogypsum on distribution of plankton communities in the southwestern Mediterranean coast. ► Phytoplankton was dominated by diatoms, ciliates by spirotrichs and copepods by Oithona nana. ► Despite human pressure, the coastal waters showed a wide diversity of species. ► It would be further of interest to see how excavation of 1.7millionm3 of phosphate influence species performances. In connection with the Taparura Project, studies of spatial distribution of the crustacean zooplankton community, nutrients, phytoplankton and ciliates were conducted in July 2007 at 45 stations spread over fifteen transects along the coast north of Sfax. The results showed that the N/P ratio was lower than the Redfield ratio, suggesting potential N limitation. Phytoplankton was characterised by the proliferation of several diatoms, while ciliates were largely dominated by spirotrichs. Copepods were the most abundant zooplankton present during the entire study period, comprising 61% of the total zooplankton community. Twelve copepod families were identified at every station, with a high percentage of Oithonidae (77% of copepods) dominated by Oithona nana. The abundance of this species was correlated with that of diatoms, Cocoolithophorideae and ciliated Colpodea, suggesting that O. nana may feed on a wide range of prey. Despite human pressure and industrial activities, the coastal waters north of Sfax showed a wide diversity of phytoplankton, ciliates and zooplankton.