Crabs as Bioindicators of Trace Element Accumulation in Mediterranean Lagoon (Bizerte Lagoon, Tunisia).

• Main Authors: Moez Shaiek, Noureddine Zaaboub, Deniz Ayas, Maria Virgínia Alves Martins, Mohamed Salah Romdhane
• Format: Article
• Language: English
• Published: Universidade do Estado do Rio de Janeiro 2018-01-01
• Series: Journal of Sedimentary Environments
• Subjects: Sediment. Pollution. Availability of trace elements. Bioindicators. Bioaccumulation. Crabs.

Nine crab species samples, males and females, were collected after homogeneously prospection of sediment surface of Bizerte Lagoon. Crabs were caught by dip net from Bizerte Lagoon during spring 2012. Concentrations of metals (Zn, As, Cd, Cr, Cu, Fe, Ni, Pb and Zn) were evaluated in the carapace and muscle tissue of crabs and in surface sediment samples. Concentrations of metals accumulated in the benthic crabs tissues were compared to the reactive metals content that constitute the bioavailable fraction of the sediments. Total organic carbon and carbonate contents were also determined, since they are principal requirements associated with crab development. Results of this work indicate that, in the study area, the metals that reach the highest concentrations in the sediments-water interface are by decreasing order Zn, Cr and Pb. The reactive concentrations of these metals are also the highest. However, the trace elements that are being accumulated in the carapace and muscle of crabs are mainly As and Cu. Continental waters flowing into the Bizerte Lagoon are the main source and the principal cause of the enrichment of trace elements in sediment. Results highlight that the reactive concentrations of metals in sediments were the principal cause of their bioaccumulation in the crabs tissues. The important results of this work highlight that cabs can be very useful on studies of monitoring and evaluation of environmental quality in addition to data obtained from the sediment as they also give information about the bioaccumulation of metals through the oceanic food webs.