春灌背景下黄河上游清水河流域DOM的空间分布规律

To provide more reliable information for water environment treatment and pollution source tracking in the Yellow River Basin, the three-dimensional fluorescence spectra technology combined with ultraviolet-visible absorption spectra and various statistical methods are applied to analyze the spatial distribution, spectral characteristics, pollution source of dissolving organic matter (DOM) in the Qingshui River basin in this study. The results show that spatial differences of water quality indices in spring irrigation season of the Qingshui River are large. In addition, the concentration of protein-like substances in DOM is higher than that of humus-like substances, and the characteristics of autogenous sources are stronger than those of terrestrial sources. The proportion of newly generated DOM is relatively large, which means that DOM mainly comes from microbial activity, the product of bacterial degradation and metabolism in water. Six principal components are identified by using PARAFAC, including four protein-like components (C1, C2, C3, C5) and two humus-like components (C4, C6). The spatial difference of protein-like components is more obvious than that of humus-like components, which are greatly influenced by endogenous factors of reservoir and sewage effluent. Four principal components, C5, fluorion, C2, and HIX, are spotted after applying the PCA approach, which can also be the descriptive indicators.