Absorption properties of chromophoric dissolved organic matter in highly-polluted Yundang Lagoon, China

Optical properties of chromophoric dissolved organic matter (CDOM) from highly polluted Yundang Lagoon, China were investigated from April 2008 to June 2009. The absorption spectra of DOM from this polluted saline lake resembled that of DOM from other natural environments. The spatial distribution of absorption coefficients at 280 nm (a280) indicated that sewage discharge was the main source of CDOM in this lagoon. A notable seasonal variation of a280 was observed from spring of 2008 to spring of 2009, indicating the reduction in sewage discharge from municipal works. Most values of spectral slope ratio (SR) of CDOM absorption were >1, implying that sewage-derived DOM has a low molecular weight. There was a significant linear correlation between a280 and the DOC concentration, demonstrating the feasibility to use optical properties of DOM to assess the degree of organic pollution in highly-polluted aquatic environments. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Conference ESIAT2011 Organization Committee.