Pollution assessment and distribution characteristics of petroleum hydrocarbon in surface sediments in the Laizhou Bay

According to the 2013－2018 monitoring data of five cruises in the Laizhou Bay, the pollution status and spatial distribution characteristics of petroleum hydrocarbons in the surface sediments were evaluated and analyzed. The results showed that the content range of petroleum hydrocarbons in the surface sediments of Laizhou Bay was ND～377.00 mg/kg, with an average of 63.34 mg/kg, which indicated that the pollution extent was light. The analysis results showed that the spatial dispersion extent of inter-annual petroleum hydrocarbon content at the monitoring stations was high, while the difference was not significant, and the clustering similarity was low, and the grouping was not obvious. The results showed that human activities such as port and shipping were the main factors affecting the distribution of petroleum hydrocarbons. The annual variation of petroleum hydrocarbon content in the surface sediments was not obvious, and the obvious annual variation area of each monitoring station was distributed in SW－NE (southeast northwest) direction.