Environmental Quality Assessment of Bizerte Lagoon (Tunisia) Using Living Foraminifera Assemblages and a Multiproxy Approach

Abstract

This study investigated the environmental quality of the Bizerte Lagoon (Tunisia) through an integrated approach that combined environmental, biogeochemical, and living benthic foraminiferal analyses. Specifically, we analyzed the physicochemical parameters of the water and sediment. The textural, mineralogical, and geochemical characteristics of the sediment, including total organic carbon, total nitrogen, simultaneously extracted metals (SEM), acid volatile sulfides (AVS), chlorophyll a, CaCO3, and changes in bacterial populations and carbon isotopes were measured. The SEM/AVS values indicated the presence of relatively high concentrations of toxic metals in only some areas. Foraminiferal assemblages were dominated by species such as A. parkinsoniana (20–91%), Bolivina striatula (<40%), Hopkinsina atlantica (<17%), and Bolivina ordinaria (<15%) that cannot be considered typical of impacted coastal lagoons both in Mediterranean and northeast Atlantic regions. The results of this work suggest that Bizerte Lagoon is a unique setting. This lagoon is populated by typical marine species that invaded this ecosystem, attracted not only by the prevailing favorable environmental conditions but also by the abundance and quality of food. The results indicate that the metal pollution found in some areas have a negative impact on the assemblages of foraminifera. At present, however, this negative impact is not highly alarming.

Assessment of the Trophic State of Saquarema Lagoonal System, Rio De Janeiro (Brazil)

“…Siqueira et al (2006) observed the TS mean value of 6.03% in Santos estuary (São Paulo State, Brazil). Using the same TS methodology of the present study, Clemente et al (2015) recorded the mean value of 1.4% in Guanabara Bay; recorded values varying from 0.03% (IT02) to 1.73% (IT10) in Itaipu Lagoon (both in Rio de Janeiro State); and Martins et al (2016) found values of 0.04% in Bizerte Lagoon (Tunisia).…”

Geochemical and Mineralogical Fingerprints of the Sediments Supply and Early Diagenetic Processes in the Bizerte Lagoon (Tunisia)

“…This work is based on the study of sediments collected in March 2013 in 10 sampling stations georeferenced with a GPS, in the Bizerte Lagoon (Tunisia, Fig. 1), the same stations studied by Martins et al (2015aMartins et al ( , 2016. This work reanalyzes some selected data obtained by these authors and new geochemical data, namely lithogenic and biogenic chemical elements.…”

“…Both analyses were performed in the fine fraction. The detailed description of the procedures applied in the sediment analyses is found in Martins et al (2015aMartins et al ( , 2016. Total organic matter (TOC) content was determined with a Leco equipment.…”

Spatial sedimentary distribution, seasonality and the characteristics of organic matter on Fernando de Noronha insular shelf

“…In pristine environments, salinity, temperature, organic matter, dissolved oxygen affects the foraminifera, but the Fernando de Noronha's port area, are susceptible to the anthropic stressors, including heavy metals and polycyclic aromatic hydrocarbons (PAHs). However, the absence of the tests could be more probably linked to the local dynamics and no preservation than to the human stressors influences (Frontalini & Coccioni, 2011;Martins et al, 2013Martins et al, , 2015aMartins et al, , 2015bMartins et al, , 2016Dijkstra et al, 2017).…”