Spectral characteristics of chromophoric dissolved organic matter in Liaohe River estuary in autumn

Absorption spectroscopy and fluorescence excitation-emission matrix spectroscopy (EEMs) of chromophoric dissolved organic matter (CDOM) were studied in Liaohe River estuary in autumn 2013.Parallel factor analysis was applied andresults show that four fluorescent components were detected in Liaohe River estuary in Autumn,2013,which included two humic-like components,(C2 (235 (310) nm/390 nm) and C3 (230 (265,360) nm/445 nm)),and two protein-like components,(C1 (225 (280) nm/330 nm) and C4 (250 nm/305 nm)).The two humic-like components behaved conservatively in the whole estuary,while the two protein-like components were non-conservative at the same time.Based on the a(355) data,the concentration of CDOM generally decreased from the river to the sea.And CDOM was primarily contributed by terrestrial discharge.The significant positive relationship between a(355) and humic-like components suggested that humic-like fluorophores and chromophores of CDOM had similar source and structure.