The Fractional Composition of Phosphorus in Edku Lagoon and Adjacent Marine Sediments, Egypt

Four short sediment cores representing different sub basins of Edku lagoon and two cores from the adjacent marine sediments were studied. The sediments were sequentially analyzed to determine four phosphorus fractions (Pex, POH, PHCl and PR) and non-sequentially treated for total-P (TP) and inorganic P (IP). The results generally showed that the fraction associated with apatite mineral (PHCl) is the dominant. It constitutes 56% and 52% of the TP for lagoonal and marine sediments implying that apatite is the main storage of PO4 ¯ ¯, while the exchangeable and associated with CaCO3 (Pex) fraction is the least content representing 6% and 4% for the lagoonal and marine sediments, respectively. The lagoon sediments are controlled by three factors namely, organic, biogenic and inorganic phosphorus factors. While the marine sediments are controlled by silt/clay factor, biogenic and inorganic phosphorus factors.