Journal of Hydrology | 2019
Characterization of CDOM in reservoirs and its linkage to trophic status assessment across China using spectroscopic analysis
Abstract
Abstract Chromophoric dissolved organic matter (CDOM) represents the optically active component of the DOM pool, and originates from both allochthonous and autochthonous sources. The fluorescent characteristics of dissolved organic matter (FDOM) has been widely used to trace CDOM sources and infer its composition. However, little is known about the optical and fluorescent properties of CDOM in drinking water reservoirs, and the variability of CDOM properties along trophic gradients in these aquatic systems. A total of 536 water samples were collected between 2015 and 2017 from 131 reservoirs across China to characterize CDOM and FDOM properties using both light absorption and fluorescence spectroscopies, and examine relationships with water-quality condition as expressed by the modified trophic state index (TSIM) of the reservoirs (range: 12\u202f \u202f70. This method highlights the importance of CDOM fluorescence for aquatic DOM input and strengthens the linkage between the trophic status index and CDOM characteristics, it also contributes to establish a new rapid assessing model with quick experimental measurements to monitor the trophic status of water reservoirs.