مرکز منطقه ای اطلاع رساني علوم و فناوري - The use of sediments to Assess the impact of Selaata phosphate plant on Batron coastal Area (Lebanon, Levantine Basin)

Abstract :

The sediments of twelve coastal stations located in Batroun marine area (North Lebanon, Levantine basin) which is subjected to the impact of Selaata phosphate fertilizers plant were studied horizontally and vertically during summer of 2003. In order to delimit the factory s spatial influence, the distribution of inorganic phosphate in surface sediments was explored and compared with orthophosphate mean concentrations in surface water. Also in order to draw a chronological history for the plant s functioning, the vertical distribution of inorganic phosphate associated with organic compounds (carbohydrates, proteins and lipids) distribution in the different levels of sediment down to 15 cm was studied. The concentrations of inorganic phosphate varied from 597 to 2279 mu g.g-1 in the surface sediments of the stations located out of the main outlets influence (M1 to M6 and M12 to M13) , while they were extremely high. fluctuating between 8068 and 64256 mu g.g-1 at the stations (M7 to M10) located under the direct influence of Selaata factory. A significant positive correlation existed between the inorganic phosphate in sediments and the orthophosphate in sea water. The whole studied area was affected by phosphate emissions and was classified into 2 zones: the first one is indirectly touched by the plant s effluents and located to the south and offshore of the factory, and the second directly influenced by the plant s outputs and located to the west and west-northern side. The penetration in the different sediment levels showed that at stations located far from the plant s main outlets, there were difficulties in determining any of plant s history because of the homogeneity of phosphate and organic matter distribution associated to strong hydrodynamism. Where as the sediments of stations located in front of the west-northern outlets could elaborate and highlight part of the phosphate factory s operational history and could show that in this zone of Batroun marine area the plant s sedimentation rate had overcome that of the natural processes.