Abstract

Dissolved organic matter (DOM) plays an important environmental and ecological role in inland aquatic systems, including lakes. In this study, using fluorescence analysis, we investigated the seasonal dynamics of DOM characteristics in Changshou Lake, which is a typical inland lake in the Three Gorges Reservoir (TGR) area. We also discuss the environmental implications of DOM for mercury (Hg) dynamics. Based on the origins of two end-members, the variations in DOM observed in this study in Changshou Lake suggest that hydrological processes (e.g., terrestrial inputs resulting from runoff and humic-like component residences) and biological activities (e.g., microbial and algae growth) are the two main principal components controlling the seasonal dynamics of DOM characteristics. Furthermore, the dynamics of dissolved Hg co-varied with variations in DOM properties, rather than with dissolved organic carbon (DOC) concentrations. This indicates that the previously reported simple correlations between DOC and Hg were not comprehensive and may lead to misunderstanding the interactions between DOM and Hg. Therefore, we recommend that when using DOM-Hg correlations to evaluate the role of DOM in the environmental fate of Hg, especially in field investigations of the spatial and temporal distribution of Hg, the properties of DOM must be taken into account. (C) 2017 Elsevier Ltd. All rights reserved.

Keywords

Three Gorges Reservoir Area; Changshou Lake; Dissolved organic matter; Fluorescence spectroscopy; Mercury; Methylmercury

Published in

Journal of Environmental Management
2018, Volume: 206, pages: 418-429

SLU Authors

• Jiang, Tao

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

UKÄ Subject classification

Environmental Sciences


Publication identifier

DOI: https://doi.org/10.1016/j.jenvman.2017.10.048

Permanent link to this page (URI)

https://res.slu.se/id/publ/92503