Absorption properties of dissolved organic matter in East Asian temperate lakes

• Published in: Limnology Vol. 24; no. 3; pp. 235 - 250
• Main Authors: Hayakawa, Kazuhide, Nakano, Shn-ichi, Li, Renhui, Sun, Fuhong, Wu, Fengchang, Takei, Naoko, Shimotori, Koichi, Imai, Akio
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01.08.2023; Springer Nature B.V
• Subjects: Absorption; Absorption coefficient; Absorptivity; Biomedical and Life Sciences; Comparative analysis; Comparative studies; Dissolved organic carbon; Dissolved organic matter; Ecology; Environment; Eutrophic environments; Eutrophic lakes; Eutrophication; Freshwater & Marine Ecology; Life Sciences; Low molecular weights; Molecular weight; Research Paper; Trophic levels; Trophic status; Trophic structure; Ultrafiltration; Ultraviolet absorption; Water purification; Chromophoric dissolved organic matter; Ultrafiltration; Ultraviolet absorption
• ISSN: 1439-8621; 1439-863X
• DOI: 10.1007/s10201-023-00722-9

There are few comparative studies of chromophoric dissolved organic matter (CDOM) in humid temperate lakes. In this study, we examined the ultraviolet absorption of water sampled from temperate lakes in Japan and China. A proportional relationship was found between the dissolved organic carbon (DOC) concentration and ultraviolet absorption coefficients in all lake samples, indicating similarities between the two parameters in the temperate lake environments. However, the ratios of absorption coefficient to the DOC concentration in the ranges of < 295 and > 320 nm showed different distributions among the lakes, even within similar DOM component of data sets. We used a two-step ultrafiltration to extract the heterogeneous parts of the CDOM from filtered water. In particular, the low molecular weight fractions in the eutrophic lakes had relative high ratios of absorption coefficient to DOC concentration. These fractions can highlight the CDOM characteristics of lakes in different trophic status.