Petroleum Hydrocarbon distribution in bottom sediment of Kemaman offshore water ad effect of different seasons

Abstract

A study has been carried out to determine the concentration and distribution of hydrocarbons in bottom sediments of Kemaman Offshore water, Terengganu. Three sampling periods were conducted during May, September and November 2007 for the sediment samples. There are 24 study stations overall which comprised three transect that layered from coastal area to offshore, where each transect comprises eight stations. From the result, total hydrocarbon for the first sampling was ranged from 45.18 mg/kg to 432.74 mg/kg dry sediment. For the second sampling, the total hydrocarbon concentration was 13.96 mg/kg to 778.17 mg/kg dry weight, while for the third sampling in November, the concentration of total hydrocarbon was 20.4 mg/kg to 506.09 mg/kg dry sediment. The mean value for first, second and third sampling are 177.315 mg/kg dry sediment, 184.324 mg/kg dry sediment and 95.127 mg/kg dry sediment respectively. The mean value shows the second sampling in the month of September has the highest hydrocarbon concentration. From this study, it showed that the study area had been polluted with hydrocarbon pollution. In this present study, the petroleum hydrocarbon ranges from 35.7 mg/kg dry sediment to 487.82 mg/kg dry sediment. The hydrocarbon content in study areas are increased from previous study that has been done in South China Sea and most of the stations are polluted with hydrocarbon as the mean value is more than unpolluted level which is 100 mg/kg.