摘要:
采用三维荧光光谱-平行因子法(EEMs-PARAFAC)分析太湖五里湖水体悬浮物中水溶性有机质(WSOM)的荧光光谱特征,研究其组分类型、分布规律以及来源,进一步探讨悬浮物中水溶性有机氮和无机氮含量与WSOM荧光组分之间的关系.结果表明,悬浮物中WSOM荧光组分主要由2个类腐殖质(C1、C2)和1个类色氨酸类蛋白质(C3)组成.总荧光强度在57.56~200.01 R.U./g之间,平均为115.42 R.U./g,其中C1、C2、C3的相对比例分别为35.55%、34.05%和30.40%;空间上由西向东逐渐增强,东五里湖高于西五里湖,沿岸区高于湖心区.荧光指数和生物源指数变化范围分别在1.48~ 2.34和0.65~ 0.87之间,反映了悬浮物中WSOM主要来源于微生物、藻类的自生生物源.多元回归统计分析结果表明,悬浮物WSOM与氮元素的迁移转化密切相关,且有机氮与WSOM荧光组分的相关系数大于无机氮.%In this paper,we apply excitation-emission matrix spectroscopy (EEMs) and parallel factor analysis (PARAFAC) to investigate the fluorescence spectral of water soluble organic matter (WSOM) in the suspended solids of Lake Wuli of Lake Taihu.We also analyze the component types and the distribution and the source of WSOM based on the obtained spectral characteristics and further study the correlation between water soluble organic/inorganic nitrogen components and WSOM components.The results show that two microbial humic-like (C1,C2),and one tryptophan-like (C3) can be identified as the principle components of WSOM.The total fluorescence intensity (Ct) is 57.56-200.01 R.U./g,with an average value of 115.42 R.U./g,with C1,C2 and C3 ratios of 35.55%,34.05% and 30.40%,respectively.In spatial,fluorescence intensity decreases from east to west in Lake Wuli,and the intensity in the lakeside area is higher than that in the center area.Moreover,fluorescence index is between 1.48 and 2.34,and biogenic index is between 0.65 and 0.87.In conclusion,WSOM in the suspended solids of Lake Wuli mainly come from microorganisms,algae aquatic and organisms.Depending on the results of multiple regression analysis,WSOM is closely related to the migration and transformation of nitrogen in suspended solids,and the correlation coefficient between organic nitrogen and WSOM fluorescent components is greater than that between inorganic nitrogen and WSOM.