Assessing the spatial and temporal variability of dissolved organic matter in Liverpool Bay using excitation–emission matrix fluorescence and parallel factor analysis

Abstract

The spatial and diurnal tidal variability of dissolved organic carbon (DOC) concentrations and the composition of dissolved organic matter (DOM), as evaluated by high-temperature catalytic oxidation and excitation-emission matrix combined with parallel factor analysis (EEM-PARAFAC), respectively, were determined in Liverpool Bay. EEM-PARAFAC modeling resulted in six fluorescent components characterized as terrestrial humic-like (two), microbial humic-like (two), and proteinlike (two). The spatial distributions of DOC and the four humic-like components were negatively correlated with salinity in the high-salinity waters observed in this study (30.41-33.75), suggesting that terrestrial DOM was conservatively distributed. The spatial patterns of protein-like components were largely different from those of DOC, humic-like components, and chlorophyll a, suggesting that these distributions were the combined result of production and degradation in the bay in addition to river inputs. These findings suggest that the DOM dynamics in Liverpool Bay are strongly controlled by river-dominated allochthonous DOM inputs with some less significant contributions of autochthonous DOM within the bay. In addition, the temporal variations of DOM associated with the diurnal tidal cycles were determined at one inshore (31.34-32.24 salinity) and one offshore (33.64-33.75 salinity) station in the bay. Negative linear relationships between salinity and DOM characteristics, i.e., DOC, humic-like, and proteinlike components, were observed at the inshore station. In contrast, no relationship was observed at the offshore station, suggesting that the export of DOM through rivers and possibly tidal flats have a noticeable influence on DOM concentration and composition up to a relatively elevated salinity of around 33 in Liverpool Bay.

UV/PAR radiation and DOM properties in surface coastal waters of the Canadian shelf of the Beaufort Sea during summer 2009

“…Indeed, component C1 has been reported as a ubiquitous FDOM component derived from the microbial degradation of phytoplankton by-products (Nagata, 2000;Stedmon and Markager, 2005;Zhang et al, 2009), as well as originating from specific Arctic terrestrial sources at low salinity (Walker et al, 2009) and various coastal and estuarine environments reported in Japan (Yamashita et al, 2008), the southeastern USA coast (Kowalczuk et al, 2009), in Liverpool Bay (Yamashita et al, 2011), and in Hudson Bay (Guéguen et al, 2011). Component 2 (C2) has been previously associated with high molecular weight and aromatic terrestrial organic matter (Stedmon et al, 2003;Walker et al (2009).…”

Linkages among fluorescent dissolved organic matter, dissolved amino acids and lignin-derived phenols in a river-influenced ocean margin

“…After the water samples reached room temperature, EEM fluorescence was measured according to Yamashita et al (2011). Briefly, emission scans from 290 to 600 nm at 2-nm intervals were acquired at excitation wavelengths between 250 and 450 nm at 5-nm intervals.…”

Characterization,Sources,and Transformations of Dissolved Organic Matter (DOM) in the Florida Coastal Everglades (FCE)

“…Unlike the common exponential decay patterns observed for C7 for the biomass leachates, C8 showed in most cases a combination of decreases and increases throughout the degradation process, suggesting that competing degradation and generation processes control the abundance of this component in the environment. Similar suggestions have previously been reported in the literature based on field data (Yamashita et al, 2008b(Yamashita et al, , 2010b) and C8 may in fact have a net accumulation in the environment after photo-or bio-degradation of DOM. As such it seems to justify its location on the PCA plot shown in figure 3.4.…”