[UV-Visible Spectra Properties of DOM from Taizi River in Benxi City Section by Multivariable Analysis]

This study investigated the ability of ultra violet-visible (UV-Visible) spectroscopy to analyze the origin,compositions,structure and humification level of dissolved organic matter(DOM). Seven surface water samples were collected from the Benxi City section of mainstream in Taizi River. Nine indices (SUVA₂₅₄, E₂/E₃, E₂/E₄, E₄/E₆, S_275-295, S_350-400, A₂/A₁, A₃/A₁ and A₃/A₂), deduced from elemental analysis and UV visible spectroscopy of DOM, were used to assess the humification degree. The results showed that the characteristics of DOM were distributed along urban river and industrial wastewater discharge, and the DOM of waste water from Benxi steel plant contained a low degree of condensation of small organic molecules. E₂/E₃ showed positive correlation with E₂/E₄, and negative correlations with S_275-295, S_350-400, A₂/A₁,indicating that humification degree of DOM was not only concerned with the degree of condensation of organic molecules, but also closely associated with the ratio between humic acid and fulvic acid. Composition structure of DOM showed significant positive correlations with A₂/A₁, SUVA₂₅₄ and S_275-295, and significant negative correlations with E₂/E₃ and E₂/E₄. Based on the loadings of DOM component and scores plot of sampling sites in Taizi River (Benxi City section),the characteristics of DOM were distinctly distributed along urban river and industrial wastewater discharge, proving that the river was deeply influenced by human activity.