『Abstract
The estuarine and coastal system plays an important role of sedimentation
deposition which acts as sink of particle associated contaminants
such as heavy metals and polycyclic aromatic hydrocarbons. Sediments
conserve important information about past conditions of its aquatic
environments. The chronology was developed by using the accumulation
rates determined previously from 210Pb analyses of
the same core. Then, the concentrations of Cr, Cu, Fe, Hg, Mn,
Ni, Pb, V and Zn were determined in dated (210Pb chronology)
sediment cores from four stations (W0, W2, W6, W9)
around the Daya Bay of Guangdong Province (China), where the first
nuclear power station of China has been running from 1994. Based
on sediment flux (g・cm-2・year-1) obtained
from the chronologies of 210Pbex, the flux of heavy
metals were calculated. The increasing of both sediment flux and
pollution concentration resulted in the increasing of heavy metals
flux (mg・cm-2・year-1 from last century.
The experimental data showed that the average values of heavy
metals are 18.6, 0.035, 32.9, 38.1, 10.6, 74.9, 4.1, 29.1×103
and 543 mg/kg for As, Cd, Cr, Pb, Cu, Zn, Co, Fe and Mn, respectively.
The concentration of As, Pb, Zn, total organic carbon (TOC) and
total nitrogen (TN) in cores are clearly higher than those of
natural abundance. Those results indicate that there is pollutant
of As, Pb, Zn, TOC and TN in the studying area. The significant
relationships between organic C and As, Cr, Pb, Zn, N indicated
that such metals are mainly delivered to Daya Bay sediments from
a common source.
Keywords: Heavy metals; Sediment flux; Daya Bay; 210Pbex』
1 Introduction
2 Materials and methods
2.1 Study area and sampling stations
2.2 Sample preparation and analytical procedures
2.2.1 Dating
2.2.2 Metal analysis
3 Results and discussion
3.1 Geochemical characterization
3.2 Apparent 210Pb chronologies
3.3 Heavy metals distribution
4 Conclusion
Acknowledgements
References