Aliağa Körfezi (İzmir) Sedimanlarında Ağır Metal Kirliliğinin Tespiti
Özet
In order to investigate the heavy metal accumulation and distribution, the anthropogenic and geological factors that are likely to cause pollutionin the marine sediments of the Aliaga Bay, which is located in Aegean Sea and surrounded by intensive industrial activities, 3 gravity cores and 15 surface sediments were taken from the sea with MTA Selen Research Ship. Geochemical (Fe, Al, Zn, Mn, As, Cr, Cu, Co, Ni, Pb, Mo, V), mineralogical, grain size, carbon and manyetic susceptibility analysis were performed on the samples and the relationship between the parameters were investigated using statistical methods. In order to determine the possible pollution levels in sediments, by using the world average shale metal concentrations as backgroundvalues, Enrichment Factor (Ef), Geo-accumulation Index, Contamination Factor (Cf) and Pollution Load Index (PLI) were calculated. According to Ef values, while surface samples showed values reaching up to significant enrichment values for Mo and they showed minimum and moderate enrichment for As and Pb. For other metals, there was a minimum enrichment in the samples. According to the Igeo values, the surface samples showed values reachig up to moderate pollution values for Mo, whereas values for As and Pb showed unpolluted and from unpolluted to moderately polluted classes. For the other metals, samples were in the unpolluted class. According to the Cf values, while surface samples showed moderate and significant contamination for Mo, they all showedmoderate contamination for Pb, and low and moderate contamination for As and Cr. According to PLI values, the surface sediments were in unpolluted class. Core samples showed values reaching up to moderate enrichment values for As, Pb and Mo according to Ef values. According to the Igeo values, only in AKRT 01 core, values reaching up to moderate pollution for Pb and Mo were seen, for As, all cores showed unpolluted and from unpolluted to moderately polluted classes. While it is possible to relate the high metal values obtained in the western part of the bay with the ship dismantling facilities and refinery, it is possible to relate the values measured on the eastern side of the bay exit, with the materials carried by Güzelhisar Creek where industrial and domestic wastes are discharged. The fact that As and Pb contents of the volcanic rocks in the Aliağa region are relatively high compared to the average crust values and that the thermal waters in the region contain high As indicate that the geological effect is also important in the region. In addition, heavy metals generally show a positive correlation with TOC, silt and clay content, whereas sand and gravel content generally show a negative correlation, indicating that heavy metals are retained by fine-grained sediments and organic materials.
