| Title |
The Distribution of Organic Carbon and its Decomposition Rate in the Kum River, Korea |
| Authors |
장창원 ( Chang Won Jang ) ; 김재구 ( Jai Ku Kim ) ; 김동환 ( Dong Hwan Kim ) ; 김범철 ( Bom Chul Kim ) ; 박주현 ( Ju Hyun Park ) |
| Keywords |
Decomposition rate; Dissolved organic carbon; Kum River; Particulate organic carbon |
| Abstract |
The distribution of organic carbon and its decomposition rate were studied in the middle and down stream reaches of the Kum River system, Korea. Water samples were collected from May to June in 2006 at seven mainstream sites and three tributary sites from the river mouth to the Daechung Reservoir outlet. The change of DOC and POC were measured during incubation for the determination of decomposition rate. The reduction of organic carbon during 20 days` incubation was regarded as labile or biodegradable organic carbon (LDOC, LPOC), and the remaining organic carbon was regarded as recalcitrant organic carbon. The mean TOC was 5.17 (±1.49) mgC·L-1 in the mainstream sites and 7.09 (±1.48) mgC·L-1 in tributary sites, respectively. TOC comprised of 62% DOC and 38% POC. LPOC was approximately 68% of POC, while LDOC was only 24% of DOC. Mean decomposition rate of TOC was about 0.03 day-1. Mean decomposition rates of LPOC ranged from 0.10 day-1, and that of LDOC was approximately 0.08 day-1. The decomposition rate of both LPOC and LDOC did not show significant difference between mainstream and tributary sites. The result of this study can give a guide to the selection of parameters in the calibration processes of water quality models. |