Characterization of Dissolved Fulvic Acid Extracted from the Stream Water in the Kushiro Bog.

Dissolved fulvic acid extracted from the stream water was characterized. The stream named Omoshironbetsu River runs through Kushiro Bog, eastward of Hokkaido Prefecture, Japan. The surface water of this stream showed yellow color, and it implied dissolution of humic substances derived from marsh plants. However, we attributed the fulvic acid to the woody tissues rather than the marsh plants by the analyses of stable carbon isotope and lignin-phenol compounds. And the contribution of the fulvic acids in DOC of this stream water was about 30% regardless of the season.