Characteristics of absorption and fluorescence spectra of dissolved organic matter from confluence of rivers: Case study of Qujiang River-Jialing River and Fujiang River-Jialing River

Abstract

Three-dimensional fluorescence spectroscopy combined with ultraviolet-visible (UV-Vis) absorption spectra was used to investigate the change characteristics of dissolved organic matter (DOM) in confluences water of Qujiang River-Jialing River and Fujiang River-Jialing River, respectively. The results suggested that DOM showed a significant terrestrial input signal in all the sampling sites, FI<1.4, HIX>0.8, possibly representing remarkable signals of humus resulted from humic-like component. Moreover, the mixing zone of this study showed a non-conservative mixed behavior, which had a limited contribution, and was not the dominant factor to interpret the change characteristics of DOM in confluences zones. Different land-use types along all the rivers had an obvious impact on DOM inputs. Results of cluster analysis showed that a higher degree of aromaticity and humification components was observed as the predominant contributor to DOM when the land-use type was forest and farmland ecosystem, for example the confluences of Qujiang River-Jialing River. On the other hand, high concentrations of DOM with relative simple structures were found in the water when the urban land-use type was predominant, for example the confluences of Fujiang River-Jialing River. Meanwhile, a new fluorescent signal of protein-like components (peak T) appeared, which manifested a significant effect on the water quality resulted from anthropogenic activities.

Keywords

Dissolved organic matter; Land-use types; River confluences; Three-dimensional fluorescence spectroscopy; Ultraviolet-visible absorption spectra

Published in

Huan Jing Ke Xue
2015, volume: 36, number: 3, pages: 869-878
Publisher: Science Press

SLU Authors

• Jiang, Tao

  • Department of Forest Ecology and Management, Swedish University of Agricultural Sciences
    
  • Southwest University

UKÄ Subject classification

Oceanography, Hydrology, Water Resources

Publication identifier

• DOI: https://doi.org/10.13227/j.hjkx.2015.03.016

Permanent link to this page (URI)

https://res.slu.se/id/publ/132043