The Variation of Petroleum Hydrocarbon Concentration and the Relationship Between Petroleum Hydrocarbon and Environmental Factors in Jaozhou Boy

The petroleum hydrocarbon concentrations and distribution features in Jiaozhou Bay from 1997 to 2004 are analyzed and discussed.The results show that the mean concentration of petroleum hydrocarbon is 44.56 μg/L,varying from 0.03 to 430.00 μg/L in Jiaozhou Bay and at most of the survey sataions,the water quality reached Grade Ⅱ according to the National Seawater Standard.The petroleum hydrocarbon concentrations are higher in the east and northeast of the Bay.In adition,the variation of annual average petroleum hydrocarbon concentration,which was in the range of 28.52—50.94 μg/L,was not significant during the survey period and only in 2003,the petroleum hydrocarbon concentration was higher than 50 μg/L.The seasonal variations in petroleum hydrocarbon in Jiaozhou Bay indicate that among the three seasons,the average concentration of petroleum hydrocarbon was highest in August,lower in May,and lowest in October.The relationship between the petroleum hydrocarbon concentration and the environmental factors shows that there exists a certain positive correlation between the petroleum hydrocarbon concentration and the dissolved inorganic nitrogen as well as phosphate,suggesting that they might come from a similar source.