Abstract: Fluorescence characteristics of dissolved organic matter (DOM) in sediment pore water of the Bosten Lake were investigated using the 3D fluorescence spectroscopy. There were 2-4 fluorescence peaks in the fluorescence spectra of the samples. Peaks A and C were the protein peaks, peak B was the fulvic acid peak, and peak D the humic acid peak. At the sampling sites from No.1 to No. 10, the fluorescence intensity of peaks A and C was higher than peaks B and D. Fluorescence intensity of all peaks was generally in a decrease trend from the entrance to the lake center. There was no the significant correlation between salinity and fluorescence intensity. Fluorescence intensity of DOM in pore water was increased with the increase of sediment depth. Average value of r(B/D) was 1.01. Humic fluorescence intensity was stable, and the change of organic matter structure and maturity was not significant, indicating that they might come from the same source. Fluorescence intensity ranged from 1.80 to 2.10, and its average was 1.82, These revealed that DOM in the Bosten Lake originated from biological sources. These novel findings are important in studying the sources, properties and interaction with pollutants of DOM in aquatic environment.

Key words: DOM; fluorescence intensity; 3DEEM')">DOM; fluorescence intensity; 3DEEM, sediment; pore water; the Bosten Lake; Xinjiang