摘要：The spatial distribution characteristics and molecular structure of dissolved organic matter (DOM) in sediment of Lake Baiyangdian were studied using ultraviolet-visible (UV-Vis) spectra and excitation emission matrix (EEM) spectra. This study provides more information for ecological environment government and restoration of Lake Baiyangdian. Four components were identified in the upper samples (0-5cm), including UV fulvic-like (peak A), protein-like (peak T2 and peak T1) and visual fulvic-like (peak C). The same components were found in the lower samples (5-10 cm) in a different configuration: Two UV fulvic-like (peak A1 and peak A2), protein-like (peak T) and visual fulvic-like (peak C). The variation was caused by the different horizonal and vertical distribution the samples. Protein-like substances dominated in all samples, especially in the upper samples, while UV fulvic-like and protein-like substances dominated in the lower samples together. UV-Vis spectra results suggest that the percentage of aromatic was higher in cleaner water regions and lower in water regions that receive more pollutants, and that the degree of humification increased from the sediment surface to the lower samples. Correlation analyses represented the relationships among the different parameters and integrated them. The results indicated that wastewater discharge and aquaculture are the main reasons for DOM variation in Lake Baiyangdian.
