Benthic foraminiferal assemblages as pollution proxies along the coastal fringe of the Monastir Bay (Tunisia)

Abstract

The Monastir Bay is one of the most important resources of marine diversity in Tunisia. The marine biodiversity quality of its coastal area has been however affected by several industrial, fishing and fish-farming activities. A multidisciplinary characterization based on geochemical analyses of sediment and benthic foraminifera was undertaken to evaluate the environmental quality of marine sediments. The geochemical data combined with the statistical results suggests an overall contamination of sediment mainly by Zn, Ni and Cu and the identification of an area particularly polluted. This zone corresponds to the area in front of the Khniss drain that has been historically affected by the presence of multiple sources of pollution. The site is also characterized by a poorly diversified benthic foraminiferal assemblage, reflecting the poor environmental conditions. Some species such as Quinqueloculina seminula and Vertebralina striata appear to be positively related to EF and might be considered as tolerant taxa to pollution in the Monastir Bay. The present study further reinforces the application of benthic foraminifera as proxies of pollution and as bioindicators of the environmental quality and represents among the first contributions in a Tunisian coastal marine area based on living benthic foraminifera as bioindicators.