Next Article in Journal
Acute Water-Scarcity Monitoring for Africa
Previous Article in Journal
Water Resources Allocation Systems under Irrigation Expansion and Climate Change Scenario in Awash River Basin of Ethiopia
Open AccessArticle

Optical Properties of Dissolved Organic Matter and Controlling Factors in Dianchi Lake Waters

1
Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China
2
Chinese Research Academy of Environmental Sciences, Beijing 100012, China
3
Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China
*
Author to whom correspondence should be addressed.
Water 2019, 11(10), 1967; https://doi.org/10.3390/w11101967
Received: 14 August 2019 / Revised: 17 September 2019 / Accepted: 19 September 2019 / Published: 21 September 2019
(This article belongs to the Section Aquatic Systems—Quality and Contamination)
Characterization of dissolved organic matter (DOM) is useful in understanding environment quality and carbon cycling in the lake system. In this study, the fluorescence of DOM, major ions, and nutrients in water were investigated to understand the sources and the transformation of DOM in Dianchi Lake, the sixth largest freshwater lake in China. The dissolved organic carbon content in water above the deposition layer was higher than 5 mg C∙L−1 but lower than that in pore water. Two primary components of humic (C1) and protein-like components (C2) were identified using parallel factor (PARAFAC) modeling on sample fluorescence spectra. Organic components were related to mineral structures, and encapsulation of bacterial or algal cells into particulates could be disintegrated to release DOM. The aromaticity and the hydrophobicity of optical properties were regulated by percentages of chromophores (CDOM) of DOM in surface water, whereas by percentages of fluorophores (FDOM) in DOM in pore water, the underlying water layer was defined as a belt of transition. The molecular weight enhanced with percentages of C1 in CDOM increased in water above the sediment layer and the pore water at the northern lake site, but molecular weight attenuated with percentages decreased in pore water at the southern lake site. DOM not only originated from particulate decomposition but also derived from internal transformation among different, dissolved organic molecules. Small molecules were aggregated into larger ones, and, conversely, large molecules decomposed into small sizes. Another speculation is that dissolved molecules adsorbed or were encapsulated into particulates or were degraded and released into dissolved phases. The precise factors regulated composition, structure, and spectral properties of dissolved organic matter in the Dianchi Lake. This study highlights that sources of DOM and transformation mechanisms in the lake water could be correlated with nutrients and primary geochemical factors for mobility and distribution in different water compartments. View Full-Text
Keywords: dissolved organic matter; lake water; optical properties; fluorescence; transformation dissolved organic matter; lake water; optical properties; fluorescence; transformation
Show Figures

Figure 1

MDPI and ACS Style

Xiao, M.; Wu, F.; Yi, Y.; Han, Z.; Wang, Z. Optical Properties of Dissolved Organic Matter and Controlling Factors in Dianchi Lake Waters. Water 2019, 11, 1967. https://doi.org/10.3390/w11101967

AMA Style

Xiao M, Wu F, Yi Y, Han Z, Wang Z. Optical Properties of Dissolved Organic Matter and Controlling Factors in Dianchi Lake Waters. Water. 2019; 11(10):1967. https://doi.org/10.3390/w11101967

Chicago/Turabian Style

Xiao, Min; Wu, Fengchang; Yi, Yuanbi; Han, Zenglei; Wang, Zhongliang. 2019. "Optical Properties of Dissolved Organic Matter and Controlling Factors in Dianchi Lake Waters" Water 11, no. 10: 1967. https://doi.org/10.3390/w11101967

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop