| Title |
Study on the Effects of Stratification and Sediment Organic Matter Characteristics on Methane Production in Asan Lake |
| Authors |
이선렬 ( Sun Ryeol Lee ) , 오해성 ( Haeseong Oh ) , 최정현 ( Jung Hyun Choi ) |
| DOI |
https://doi.org/10.15681/KSWE.2024.40.5.215 |
| Keywords |
Dissolved organic matter; Lake; Methane; Parallel factor analysis; Sediment; Stratification |
| Abstract |
Lakes are one of major sources of methane gas due to anaerobic decomposition of organic matter in sediments. Since methane released from lakes is a greenhouse gas, it is necessary to investigate factors affecting methane production of lakes. This study conducted field and incubation experiments in Lake Asan in August and October to determine effects of thermal stratification and sediment organic matter characteristics on methane production. Field experiments measured temperature and dissolved oxygen to determine the formation of thermal stratification of lakes. Methane and organic matter characteristics were analyzed using gas chromatography, Total Organic Carbon (TOC) analyzers, and fluorescence spectroscopy. Incubation experiments under anaerobic conditions used sediment and water samples from the same site. Field results showed higher methane fluxes in August and increased Dissolved Organic Carbon (DOC) concentration closer to Asan Bay seawall. Elevated methane fluxes and DOC concentration resulted from intensified anaerobic decomposition formed by thermal stratification. Incubation results indicated that sediment organic matter characteristics influenced methane flux between sites. Statistical analysis revealed that thermal stratification could be a primary factor affecting methane production of lakes. Characteristics of sediment organic matter with respect to quantity and quality could be factors influencing methane production of lakes. Results of this study can serve as fundamental data for predicting methane emissions from lakes due to climate change and for mitigating lake’s contributions to global warming. |