Molluscan assemblage as pollution indicators in Al-Khobar coastal plain, Arabian Gulf, Saudi Arabia

Abstract

To assess the anthropogenic sources of pollution along Al-Khobar coastal area, Saudi Arabian Gulf, bivalve and gastropod shells were collected from 15 sites for Al, Sr, Ni, Fe, Hg, Zn, Cr, Se, Co, Cd, Cu, As, Mn and Pb analyses using Inductively Coupled Plasma Mass Spectrometer. The molluscan assemblage was composed of shallow sandy bottom in-fauna, and hard rocky shore epi-fauna. Results indicated a decrease in the frequency of the molluscan assemblage and an increase in the abundance of some taxa and the average values of some heavy metals in the gastropods and bivalve shells in comparison with those in worldwide seas and gulfs. Correlation analyses and principal component analysis classified metals in the studied molluscans into two groups. The abundance and frequency of the molluscan assemblage along Al-Khobar coastline may be attributed to their mode of life, tidal currents, and pollutants from desalination process, oil exploration, transportation, and industry and sewage discharges.