Abstract
In Lake Kojima, the profiles of UV absorbance and dissolved COD obtained by gel chromatography, showed mainly two patterns at the periods of irrigation and non-irrigation. However, the dissolved COD concentration was nealy constant, 6mg·l-1 in all seasons. Both organic compounds in lower moleculer-weight fraction separated by Sephadex G-15 and relationship between MBAS and D-COD in February, suggested the influence of domestic effluents at the non-irrigation period. Gel chromatograms of experimental model water samples prepared with soil in paddy field suggested that organic pollutants in Lake Kojima were affected by domestic effluents and paddy fields.
