乌梁素海沉积物孔隙水中溶解有机质的荧光及紫外光谱研究

运用紫外可见光吸收光谱与荧光光谱研究乌梁素海沉积物孔隙水中溶解有机质的来源、结构及腐殖化程度。r_(A，C)、HIX、SUVA₂₈₀和SUVA₂₅₄等被用于表征DOM的腐殖化程度和芳香构化程度及结构，f_450/500用于指示DOM的来源。研究结果表明：腐殖化程度最高的点为湖泊东部的W4样点，腐殖化程度最低的为总排干影响区域的W1样点。E_253/203表明湖泊入口处沉积物孔隙水中有机质主要为不可取代的芳香环结构。荧光指数f_450/500为1.57～1.82之间。总体而言，f_450/500的值更接近于1.6，处于2个端源中间，说明乌梁素海DOM中的腐殖质主要来源于陆源输入。相关分析的结果表明， DOM的不同来源对其腐殖化程度产生影响。随着腐殖化值的增大，DOM的来源由生物源向陆源过渡。

Study on fluorescence spectra and UV vis spectra of dissolved organic matter collected from sediment pore water in Wuliangsuhai Lake

UV-vis absorption spectra and fluorescence spectra were used to study the origin,structure and humification degree of DOM in sediment pore water from Wuliangsuhai Lake.Several indices,r(A,C),HIX,SUVA280 and SUVA254,were used to characterize the humification degree and aromatic structure of DOM.Index f450/500 was used to indicate the source of DOM.The results show that the humification degree of DOM was the lowest in W1 site,which was affected by domestic sewage and industrial wastewater from the total drain.The highest humification degree was obtained at W4 site,in the east.E253/203 ratio showed that the structure of organic matter was mainly unsubstituted aromatic ring structures at the entrance.The values of f450/500 range from 1.57~1.82,suggested that DOM originated from terrestrial sources and biogenic sources.In general,fluorescence index was closer to 1.6,terrestrial sources was main source.Correlation analysis showed that humification degree and aromatic structure of DOM were affected by the source of DOM.With the increasing humification values,the sources bring about a transition from biogenic sources to terrestrial sources.