Seasonal and Regional variations of hydrocarbon levels and origin of n-alkanes in water of Southern marshes of Iraq

Abstract

Water samples werer collected for the period of (15)months from Jan.(2006) to Feb.(2007).Petrolum hydrocarbons have been studied in the dissolved and particulate phase .Three stations of Iraqi Southern marshes were examined ;Al-Bargah ,Al-Gebayesh and Al-Hammar station.Total hydrocarbons have been studied Spectroflurometry.In the dissolved phase total petroleum hydrocarbon concentrations ranged between (0.220)µgl in Al-Bargah during summer season to(0.430) µgl at Al-Gebayesh during winter (2006).Particulate phase of water samples recorded ranges between (0.191) µgg dry weight recorded at Al-Bargah during summer to (0.394) µgg dry weight at Al-Gebayesh station during winter( 2006). Gaschromatography was used to identify the concentration and origin of n-alkanes in the samples .Total n-alkanes in the dissolved phase of water ranged from (3.13) µgl and recorded at Al-Gebayesh during winter( 2006)to (2.41) µgl and recorded l at Al-Bargah during summer season . Pristane, Pytane and CPI were studied to identify the origin of n-alkanes in the samples which indicated the Biogenic origin of alkane compounds.