Sediment cores were obtained from Upo and Mokpo in Upo Wetland and core samples were divided by
depth into 20 ~ 21 subsamples. The heavy metal concentrations of Fe, Mn, Zn, AS, Cu, Cd, Ni, Pb, and Cr in the
sediments of each depth were determined by ICP-MS. The texture of sediemnts from Upo Wetland appeared to be
clayey silt with average grain size of 7.52 ~ 11.15 ㎛ for physical properties. It was found to have a clear
tendency of depth profile with respect to TOC and ignition loss. Organics were stabilized in the range of 0.5 ~ 0.7
% TOC and 8 ~ 9 % ignition loss in 30 years, whereas, the surficial sediments have the highest concentrations of
about 3.0 % of TOC and 13 ~ 15 % ignition loss. Those are much higher than the values of the main stream, the
Nakdong River, which reflects the deposit of biodegradable organics from plants and other lifes. The vertical
distribution of heavy metals in two sediment cores was investigated to elucidate historical trends of heavy metals
deposited into Upo wetland. The depth profile concentrations of each heavy metal were compared and discussed
with the Concensus-Based Sediment Quality Guidelines for freshwater ecosystems. All the Cd data for the vertical
distribution in the sediments were detected above PEC value for Cd, which predict harmful effects on
sediment-dwelling organisms expected to occur frequently. The concentrations of Zn, Cu, and Cr in all sediment
samples for depth profile were detected below the TEC values, which provided a basis predicting the absence of
toxicity by Zn, Cu, and Cr.
Sediment cores were obtained from Upo and Mokpo in Upo Wetland and core samples were divided by
depth into 20 ~ 21 subsamples. The heavy metal concentrations of Fe, Mn, Zn, AS, Cu, Cd, Ni, Pb, and Cr in the
sediments of each depth were determined by ICP-MS. The texture of sediemnts from Upo Wetland appeared to be
clayey silt with average grain size of 7.52 ~ 11.15 ㎛ for physical properties. It was found to have a clear
tendency of depth profile with respect to TOC and ignition loss. Organics were stabilized in the range of 0.5 ~ 0.7
% TOC and 8 ~ 9 % ignition loss in 30 years, whereas, the surficial sediments have the highest concentrations of
about 3.0 % of TOC and 13 ~ 15 % ignition loss. Those are much higher than the values of the main stream, the
Nakdong River, which reflects the deposit of biodegradable organics from plants and other lifes. The vertical
distribution of heavy metals in two sediment cores was investigated to elucidate historical trends of heavy metals
deposited into Upo wetland. The depth profile concentrations of each heavy metal were compared and discussed
with the Concensus-Based Sediment Quality Guidelines for freshwater ecosystems. All the Cd data for the vertical
distribution in the sediments were detected above PEC value for Cd, which predict harmful effects on
sediment-dwelling organisms expected to occur frequently. The concentrations of Zn, Cu, and Cr in all sediment
samples for depth profile were detected below the TEC values, which provided a basis predicting the absence of
toxicity by Zn, Cu, and Cr.