Program
 
General Session 4: Marine environment, ecosystem & sustainability
 

 
 
1115
Long range transport and fate of PAHs in seawater from the Western Pacific to the Southern Ocean (17.5ˇăN - 69.2ˇăS)
Monday 9th @ 1115-1135
Room 1
Mengyang Liu* , State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, PR China; College of Ocean and Earth Science, Xiamen University, Xiamen 361102, PR China
Meng Chen, College of the Environment and Ecology, Xiamen University, Xiamen 361102, PR China
Qingquan Hong, College of Ocean and Earth Science, Xiamen University, Xiamen 361102, PR China
Jing Lin, College of Ocean and Earth Science, Xiamen University, Xiamen 361102, PR China
Peng Huang, College of Ocean and Earth Science, Xiamen University, Xiamen 361102, PR China
Jiajun Hong, College of the Environment and Ecology, Xiamen University, Xiamen 361102, PR China
Minggang Cai, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, PR China; College of Ocean and Earth Science, Xiamen University, Xiamen 361102, PR China
Presenter Email: 15659821630@163.com
Persistent organic pollutants (POPs) have the potential to reach polar or pristine environments through atmospheric or oceanic long-range transport (LRT). Global change with different temperatures and organic matter stocks will influence the reservoirs of POPs especially in the polar. To investigate the fate of polycyclic aromatic hydrocarbons (PAHs) in seawater along a meridian transect, surface waters from the western Pacific to the Southern Ocean (17.5°N - 69.2°S) were collected during the 27th Chinese National Antarctic Research Expedition in 2010. The concentrations of Σ9PAH in the surface seawater ranged from not detected (ND) to 21 ng L-1, with a mean of 4.3 ng L-1, which are close to the levels found in the Japan Sea and Ross Sea. Three-ring PAHs were most abundant and accounted for 95% of the Σ9PAH. PAH ratios suggested that PAHs originated mainly from pyrogenic sources, such as grass, wood, and coal combustion. The spatial distribution of dissolved PAHs in surface water illustrated a generally increasing trend in the PAHs with increase in the southern latitude from 17°N to 32°S. The accumulation by the surficial Leeuwin Current and access to continental discharges were suggested to be responsible for the highest concentrations of Σ9PAH observed near Fremantle Harbor, Western Australia. Three-ring PAHs showed a southward decrease in the open ocean (40−60°S) while no latitudinal trend for the four-ringed. The Southern Ocean is away from direct terrestrial influence and affected mostly by the air−water diffusive process. The mass inventory of Σ9PAH in Prydz Bay were estimated to be 180 tons. This calculation highlighted the role of intermediate and deep seawater as a major reservoir for PAHs in seawater. and suggested that climate change rarely shows the rapid release of the PAHs currently stored in the major reservoirs (intermediate and deep seawater).