Abstract
Deposits of the endemic Mediterranean seagrass, Posidonia oceanica, are usually found covering the fronts of sandy beaches. In Egypt, these deposits are thought of as waste and subjected to removal by heavy machinery. The current study provides the first report on the status and distribution of P. oceanica deposits along the Mediterranean Coast of Egypt, in addition to an assessment of trace elements (TE), organic carbon (OC), and nutrient contents of some of their banquettes. The results indicate that TE concentrations of P. oceanica litter and associated sediments and water are acceptable according to the international limits. The results also show that organic matter constituted >10% of P. oceanica litter dry weight, while OC constituted 1.9% similar to that reported for P. oceanica living tissue. A research strategy is needed to assess carbon stocks of P. oceanica meadows and their deposits along the Mediterranean coast of Egypt, in order to set strategies to mitigate climate change based on their carbon storage capacity. Local campaigns should be conducted to increase people's awareness of the importance of P. oceanica to the environment and consequently to their livelihood.