The application of Excitation/Emission Matrix spectroscopy combined with multivariate analysis for the characterization and source identification of dissolved organic matter in seawater of Bohai Sea, China

Dissolved organic matter (DOM) is a complex and poorly understood mixture of natural polymeric organic material, and plays an important role in material transport and carbon balance in aquatic ecosystems. Fluorescent dissolved organic matter (FDOM) represents a major portion of the total DOM and has often been used as a tracer to identify the source or track the movement of DOM in aquatic environment. In this work, we have applied Excitation/Emission Matrix spectroscopy (EEMs) to study the distribution and characteristics of FDOM in seawater of Bohai Sea in Northern China. Hierarchical Cluster method has been used to assess the similarities and dissimilarities of the entire EEMs data sets of seawater samples collected from different regions of the Bohai Sea. The distribution of different seawater samples as revealed by multivariate results has been used to track the movement of DOM material in the Bay, and the results from such analysis are in good agreement with those obtained from seawater circulation and dynamics models.