Abstract
The water quality in marshes and streams around the coastal peatland at the Pacific seaboard of the Tokachi district, Hokkaido, Japan, has been examined. Water samples collected from the river affected by peatland were turning brown and showed specific characteristics proper to the peatland river water. The dissolved organic matter contents were significantly higher than those in the river less affected by peatland. However, the influence was relatively lower in the present peatland than the water quality in the peatland with wide area. The high ion exchange ability of peat also affected the composition of dissolving inos. Although water quality of the lake was similar to that of the river, the influence of saltwater was remarkable in the lake near seaboard. Significant positive correlation was found between dissolved organic matter contents and concentration of dissolved iron. However, it could not be concluded that only humic acid contributes to the chelating reaction with iron. It was inferred that organic anions play an important role on maintaining the balance of charges in the water samples affected by peatlands. It has been revealed that further study is needed on the quantification of non-humic substances.
