title: Identification of sources and seasonal variability of organic matter in Lake Sihwa and surrounding inland creeks, South Korea.
abstract: Coastal areas are subjected to significant allochthonous organic matter deposits from surrounding areas; however, limited information is available on the source and delivery of this organic matter. In this study, to assess seasonal changes in the sources of organic matter in Lake Sihwa (Korea), biodegradability, fluorescence property, and stable isotopic compositions (carbon, nitrogen, and sulfur) of the organic matter were determined. Water samples were collected from the inner lake (n = 9) and inland creeks (n = 10) in five separate events, from November 2012 to October 2013. Organic matter originating from rural, urban, and industrial areas was examined as the potential sources. The organic matter contents and biodegradability in the industrial area were the highest, whereas low concentrations and poor biodegradability of organic matter were found in the rural area, and moderate properties were observed in the urban area. In Lake Sihwa, a large concentration of total organic matter and enhanced biodegradability were observed during March and August. However, main source of organic matter differed between the sampling events. The largest contribution of organic matter, deriving from marine phytoplankton, was found in March. On the other hand, in August, the organic matter originating from the industrial area, which is characterized by high levels of heavy metals and persistent organic pollutants, was significantly increased. Our results could be useful to enhance the management of water bodies aimed at reducing the organic matter concentrations and improving the water quality of Lake Sihwa, and even that of the Yellow Sea.
authors.affiliation: Marine Ecosystem and Biological Research Center, Korea Institute of Ocean Science and Technology, Ansan 15627, Republic of Korea.
authors.forename: Yeonjung
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Ocean Environmental Sciences, Chungnam National University, Daejeon 34134, Republic of Korea.
authors.forename: Seongjin
authors.initials: S
authors.lastname: Hong
authors.affiliation: Department of Fundamental Environment Research, Environmental Measurement and Analysis Center, National Institute of Environmental Research, Incheon 22689, Republic of Korea.
authors.forename: Min-Seob
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Department of Marine Sciences and Convergent Technology, Hanyang University, Ansan 15588, Republic of Korea.
authors.forename: Dahae
authors.initials: D
authors.lastname: Kim
authors.affiliation: Department of Marine Sciences and Convergent Technology, Hanyang University, Ansan 15588, Republic of Korea.
authors.forename: Bo-Hyung
authors.initials: BH
authors.lastname: Choi
authors.affiliation: Department of Environment and Energy, Sejong University, Seoul 05006, Republic of Korea.
authors.forename: Jin
authors.initials: J
authors.lastname: Hur
authors.affiliation: School of Earth and Environmental Sciences & Research Institute of Oceanography, Seoul National University, Seoul 08826, Republic of Korea.
authors.forename: Jong Seong
authors.initials: JS
authors.lastname: Khim
authors.affiliation: Department of Marine Sciences and Convergent Technology, Hanyang University, Ansan 15588, Republic of Korea. Electronic address: shinkh@hanyang.ac.kr.
authors.forename: Kyung-Hoon
authors.initials: KH
authors.lastname: Shin
mesh_terms: D001673:Biodegradation, Environmental; D002247:Carbon Isotopes / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D060106:Lakes / Q000737:chemistry*; D009587:Nitrogen Isotopes / Q000032:analysis*; D010839:Phytoplankton / Q000737:chemistry; D056910:Republic of Korea; D012621:Seasons; D013455:Sulfur / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D060753:Water Quality
chemical_list: D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D014874:Water Pollutants, Chemical; D013455:Sulfur
keywords: Biodegradability; Fluorescence property; Lake Sihwa; Organic matter sources; Stable isotope ratio