Program
 
General Session 4: Marine environment, ecosystem & sustainability
 
 
 
Poster
Anthropogenic organochloride compounds as potential tracers of regional water masses: A case study of estuarine plume, coastal eddy, wind-driven upwelling and long-range warm current
GS4-40-S
Miaolei Ya* , College of the environment and ecology, Xiamen University
Yuling Wu, College of the environment and ecology, Xiamen University
Yongyu Li, College of the environment and ecology, Xiamen University
Xinhong Wang, College of the environment and ecology, Xiamen University
Presenter Email: 33120140153996@stu.xmu.edu.cn
Water masses are the crucial driving force influencing the transport processes of anthropogenic organochloride compounds (OCs). The ways in which water masses control the input sources, transport and distributions of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were investigated in the Northern South China Sea (NSCS), where water masses with different hydrological features are generated by the East Asian summer monsoon: Pearl River estuary plume (PREP), Guangdong offshore eddy (GDEC), South China Sea warm current (SCSWC) and wind-driven upwelling current (WDUC). No discrepant distributions of OC concentrations were found in these water masses. However, compositions and diagnostic ratios of HCHs, DDTs, trans or cis chlordane and PCBs could reflect the discrepancies in the input, transport and transformation of OCs caused by the hydrological characteristics of water masses, therefore, allowing them to serve as potential tracers of regional water masses. In detail, α/γ-HCH and β-HCH percentages could indicate the weathered residual in the GDEC, long-range transport in the SCSWC, atmospheric deposition in the surface WDUC and rapid biodegradation in the deep WDUC, respectively. The predominance of o, p'-DDT and p, p'-DDT could indicate continuous input in the PREP, GDEC and WDUC. DDT/DDTs of < 0.5 also reflected long-range transport in the SCSWC. DDD/DDE indicated the different oxygen environments of microbial degradation in the surface and deep water of the WDUC. Trans/cis-chlordane values could indicate the selective degradation degree of trans-chlordane in different water masses. Significantly higher penta-PCB could reflect the strong paint additive sources carried by river erosion in the PREP.