武汉南湖可溶解性有机物的来源与组成分析

Sources,Composition and Spatial Distribution of Dissolved Organic Matter in Nanhu Lake,Wuhan

该文基于光谱分析揭示了武汉市南湖可溶解性有机物(DOM)的来源组成与空间分布特征,初步探讨了DOM与南湖污染程度及原因之间的关系。利用紫外-可见光扫描计算得到α(254)的均值为(22.49±1.55)m^(-1)>10 m^(-1),说明DOM浓度偏高,南湖为富营养湖泊。根据三维荧光图谱计算得到的南湖BIX、HIX、FI、M 4个指标的均值分别为(0.94±0.07)、(4.77±0.52)、(1.59±0.10)、(6.04±0.22),表明南湖DOM为自源DOM,且主要成分为腐殖酸、大分子芳香化合物。通过三维荧光-平行因子分析法分析,认为南湖可溶解性有机物主要由4种DOM构成,其中3种为富里酸,1种为腐殖质,与指标计算结论一致。采用克里金插值法得到南湖DOM污染分布图显示南湖3个湖区差异明显,其污染严重程度排序为东部湖区>中部湖区>西部湖区。南湖总磷超标可能与南湖水中藻类消亡有关。

This paper reveals the source composition and spatial distribution characteristics of dissolved organic matter(DOM)in Nanhu Lake based on spectral analysis.And the relationship between DOM and the pollution degree and causes of the Lake were also explored.As the average value ofα(254)is(22.49±1.55)m^(-1)>10 m^(-1),this results indicated that the DOM concentration is high and the Lake is an typical eutrophic lake.The average values of the indexes BIX,HIX,FI,and M were(0.94±0.07),(4.77±0.52),(1.59±0.10),(6.04±0.22)respectively,demonstrating that DOM is originated from endoge⁃nous microbes.Excitation-emission matrix fluorescence-parallel factor analysis(EEM-PARAFAC)indicated that mainly 4 types of organic components consisted of the Lake DOM,of which three are fulvic acid and one is humic.The DOM pol⁃lution distribution map showed that the three lake areas of the Lake have obvious differences.Descending these three area ac⁃cording to the concentration of pollution with the order is Eastern Lake Area>Central Lake Area>Western Lake Area.The ex⁃cessive total phosphorus may be related to the disappearance of algae in the water of the Lake.