Riverine transport of polycyclic aromatic hydrocarbons from Kaoping
River (Taiwan) to coastal ocean
Chon-Lin Lee*a, Bing-Sian Lina and James T. Liub
a
Department of Marine Environment and Engineering, National Sun Yat-sen University, Kaohsiung, Taiwan 80424, ROC
b
Institute of Marine Geology and Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan 80424, ROC
Polycyclic aromatic hydrocarbon, as a particle tracer, provides valuable
information in land-to-sea particulate transport. Nevertheless, information of its
riverine flux to coastal ocean is sparse. Therefore, in this study, a monthly sampling
campaign in Gao-ping River was executed from NOV 2006 to NOV 2007.
Concentrations of 50 polycyclic aromatic hydrocarbons in both dissolved and
particulate phases were analyzed for water samples collected. The total PAH
concentrations ranged from 13.0 to 565ng/L and 11.8 to 502ng/L in the dissolved and
particulate phase, respectively. The particulate PAH concentrations were correlated
significantly with the total suspended particles (R2=0.90，p<0.0001). It is observed
that after the Krosa typhoon, the dissolved PAHs concentrations reached the lowest
because of heavy rainwater dilution, while both of the total suspended particle and
particulate PAH concentrations reached the highest. According to the PAH isomer
ratios, IP/IP+BghiP and BaA/228, petrogenic origin dominates at wet season (except a
sample collected with a nearby straw burning activity) while pyrogenic origin
dominates at dry season. The PAH compositional pattern also indicates the same
result. At last, during this period, the annual dissolved and particulate PAH fluxes
from river to the coastal ocean were 0.37 and 2.46 metric tons, respectively.
Compared with dry season, wet season (May to October) contributes much more in
total annual fluxes (about 89.2% and 99.6%, respectively).