title: Source identification and characterization of the accumulating non-biodegradable organics in Korean reservoirs.
abstract: An increase in the chemical oxygen demand (COD) has been noticed in most Korean reservoirs. Therefore, this research systematically investigated the causes of organic accumulation. Samples of soil affecting the quality of water of reservoirs were collected at various sources and analyzed for their organic characteristics. The COD to biochemical oxygen demand (BOD) ratio was used as the key parameter in the evaluation of non-biodegradable (NBD) organic accumulation in the reservoirs. Soil samples containing plant roots were agitated, with the supernatant showing COD/BOD ratios of less than 2.8, while those of the composted tree leaves were greater than 5.0, suggesting that humic substances produced in forest areas are a major cause of NBD organic accumulation in reservoirs. In addition, the organic fractionation of the leachate from leaching tests showed that of the various types of hydrophobic natural organic matter (NOM), the larger molecular weight humic acid makes a greater contribution than fulvic acid to the increase in the NBD COD in Korean reservoirs.
authors.affiliation: Department of Civil and Environmental Engineering, Korea University, 5-1 Anam-dong, Sungbuk-gu, Seoul 136-713, Republic of Korea.
authors.forename: Sungwon
authors.initials: S
authors.lastname: Kim
authors.forename: Seungkwan
authors.initials: S
authors.lastname: Hong
authors.forename: Geonha
authors.initials: G
authors.lastname: Kim
authors.forename: Jinsik
authors.initials: J
authors.lastname: Sohn
authors.forename: Euiso
authors.initials: E
authors.lastname: Choi
mesh_terms: D002851:Chromatography, High Pressure Liquid; D007723:Korea; D008970:Molecular Weight; D009930:Organic Chemicals / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D014873:Water Pollutants / Q000737:chemistry*
chemical_list: D009930:Organic Chemicals; D014873:Water Pollutants