| Popis: |
Surface sediment samples from the Arabian Gulf coast of Saudi Arabia were collected by Van Veen grab sampler to identify the characteristics, distribution, levels, and to discriminate between natural and anthropogenic sources of the total extractable organic matter (TEOM). The dried and sieved sediments were extracted with a dichloromethane/methanol mixture for analysis by gas chromatography-mass spectrometry. The TEOM included n-alkanes (353.9±283.8 ng.g−1), n-alkanols (283.2±296.1 ng.g−1), fatty acid methyl esters (245.2±353.7 ng.g−1), hopanes (100.7±158.2 ng.g−1), steranes (58.5±96.3 ng.g−1), triterpenoids (18.9±21.1 ng.g−1), steroids (15.3±17.0 ng.g−1), polycyclic aromatic hydrocarbons (PAHs) (0.48±1.19 ng.g−1), as well as an unresolved complex mixture (UCM =1633±3151 ng.g−1) and petrochemicals (343.1±424.2 ng.g−1). The major sources of these TEOM compound groups were anthropogenic (petroleum and petrochemical) and natural (lipids from higher plants, marine material, and microbiota) inputs. Anthropogenic contaminants from petroleum products ranged from 46.6-85.6% of the TEOM, whereas petrochemicals varied from 10.7-40.6%. Biogenic influx from terrestrial vegetation ranged from 5.7-19.3%, and marine biotic sources varied from 11.1-37.5%. The continuous accumulation of anthropogenic contaminants will ultimately affect the critical habitats of this marine coastal region. This provides a basis for further studies to understand human and developmental activities on delivery, deposition processes, distribution, and biogeochemical alteration of organic matter in the coastal zones of the Arabian Gulf. Such studies are important for sustainable development and protection of these key regional habitats. |
