| Title |
The Relationship Between the Fractionation Characteristics and Decomposition Rate of Organic Carbon in Nam River and Geumho River |
| Authors |
김호섭 ( Ho-sub Kim ) ; 김석규 ( Seok-gyu Kim ) ; 오승영 ( Seung-young Oh ) |
| DOI |
https://doi.org/10.15681/KSWE.2023.39.2.131 |
| Keywords |
Biological degradation; Decomposition rates; DOC; Organic carbon; RDOC |
| Abstract |
In this study, the relationship between organic carbon distribution characteristics and decomposition rate classified according to the particle size and biological degradation characteristics in water was investigated for the Nam river and Geumho river. The average concentrations of TOC in the Nam river and Geumho river were 2.7±1.2 ㎎/L and 5.0±1.2 ㎎/L, respectively, but the composition ratios for each type of organic carbon were similar. An average value of 8 0.9% of TOC was p resent a s DOC and 7 2.8% of DOC consisted of Refractory-DOC (RDOC). In addition, the change in the RDOC composition ratio according to temporal and spatial distribution was the smallest. There was no difference in the decomposition rate of organic carbon except for TOC by the site (p≥0.108, one-way ANOVA), and the decomposition rates of Labile-POC (LPOC) and LDOC were similar at 0.139±0.102 and 0.137±0.149 day-1, respectively (p=0.110, paired t-test). The coefficient of variation (CV) of the decomposition rate of DOC (average 8.1%), which had the smallest composition ratio of organic carbon, was 1.1, showing the largest temporal variation. The TOC, POC, and DOC decomposition rates showed a significant correlation with the ratio of the initial concentration to the concentration after 25 days of decomposition (OC25/OC0) (r2=0.89~0.94, p<0.001), and the decomposition rates of LPOC and LDOC were significantly correlated with the ratio of the initial concentration to the concentration after 5 days of decomposition (LOC5/LOC0) (r2=0.67~0.75). This suggests that it is possible to estimate the decomposition rate through the concentration of each type of organic carbon. |