Components,properties and sources of DOM in Xi'an water bodies in dry season
Due to the diversity of dissolved organic matter(DOM)in regional water bodies,3D fluorescence spectroscopy combined with parallel factor analysis and UV spectroscopy techniques were used to explore the differences in fluorescence components,sources,and molecular properties of DOM in the water bodies in the dry season in Xi'an.The results show that the DOC of the water bodies in the dry season was 2.66～9.48mg/L.DOM contained two kinds of humus-like(the average value of the total contribution rate was more than 70％)and one kind of proteinoids-like,with fulvic acid as the main matter.The main source was biological,with strong or very strong characteristics of autogenesis and weak degree of overall humification.The relative content and degree of benzene ring substitution of DOM were relatively high in the lower reaches of Chanhe River and Bahe River,Zaohe River,Linhe River,Hucheng Moat,and Caoyun Canal and relatively low with the relatively high molecular weight in Heihe River.The relative molecular weight and proportion of fulvic acid content of DOM in the lower reaches of Bahe,Zaohe,and Fenghe rivers were smaller than those in the upper reaches.The DOC demonstrated a pairwise positive correlation with UV254,α355,or the total fluorescence intensity(r=0.850～0.939,P＜0.01).The molecular properties and sources of DOM in the dry season demonstrated a spatial heterogeneity,which belonges to the humus-like dominant type.The UV254,α355 and total fluorescence intensity of DOM can be used to estimate relative content of DOM.This study can provide reference for developing effective water environment management measures.
DOMfluorescence characteristicsmolecular characteristicssourcespace distribution
万方数据
维普
