Fluorescent characteristics of CDOM in Poyang Lake analyzed by three-dimensional excitation-emission matrix spectroscopy and parallel factor analysis [鄱阳湖CDOM三维荧光光谱的平行因子分析]

作者：Liu L.-Z.; Huang Q.^*; Wu Y.-M.; Wu D.-S.; You H.-L.

来源：China Environmental Science, 2018, 38(1): 293-302.

• CDOM
• Parallel factor analysis
• Poyang Lake
• Three dimensional excitation-emission matrix spectroscopy

Based on the three-dimensional excitation-emission matrix spectrum (3DEEM) and the parallel factor analysis (PARAFAC) of Poyang Lake samples, a relationship between fluorescent components of chromophoric dissolved organic matter (CDOM) and nitrogen and phosphorus nutrients in the lake was established. Three fluorescence components were identified for CDOM including humic-like components C1 (245/391nm); C2 (255, 340/453nm), each of which accounted for 40.8% and 30.8% of total CDOM, and a tyrosine-like component C3 (275/304nm) with a contribution of 28.4% to total CDOM. The fluorescent intensities and proportion of humic-like components were the lowest in the dry season but the highest in the flooding season. On the contrary, the tyrosine-like component was the lowest contributor to total CDOM in the flooding season but the highest in the dry season. The fluorescent intensity of each component was subject to the changes in lacustral hydrological conditions. Similar fluorescent intensity of different components was observed under the same hydrological condition. The CDOM in Poyang Lake originated from both allochthonous and autochthonous sources, yet the allochthonous source dominated in the dry season. In addition, the fluorescent intensities of all components showed significantly positive correlations with total nitrogen (TN) and dissolved total nitrogen (DTN), and tyrosine-like component was significantly and positively correlated with total phosphorus (TP).