distribution of phosphorus fractions and some of heavy metals in surface sediments of burullus lagoon and adjacent mediterranean sea

Abstract

Twelve samples were collected from the surface sediments of lagoon and adjacent Mediterranean Sea. Samples were analyzed for grain size, total organic carbon (TOC), total carbonate (CaCO3), various forms of phosphorus and heavy metals (Fe, Mn, Zn, Cu, Ni, Co, Cd and Pb). The results indicated that the sediments were composed of sand, silt and clay enriched with carbonate (1.95 – 34.1%) and total organic carbon (0.06 and 3.62%). The total-P content ranged between 58 and 1186 μg/g, and the fraction associated with apatite minerals (PHCl) was the dominant (it constitutes about 50 – 73% of TP) implying that it was the main storage of phosphate. The various P phases demonstrated significant positive correlation with mean size, silt, clay, TOC, CaCO3 and TP, while only Pex was correlated with the metals. As well as, the obtained data indicated that the variations of the measured metals in sediments are varied depending on the locations, whereas the high levels were observed in the western area of the lagoon. The studied gave positively correlated with each other and organic carbon suggested that the distributions of these metals are associated with the organic matter accumulation.