Biophysical processes affecting DOM dynamics at the Arno river mouth (Tyrrhenian Sea)
Authors: Retelletti Brogi S., Gonnelli M., Vestri S., Santinelli C.
Journal: Biophysical Chemistry
DOI: 10.1016/j.bpc.2014.10.004
Abstract:
Dissolved organic carbon (DOC) and optical properties (absorption and fluorescence) of chromophoric dissolved organic matter (CDOM) were measured in October 2012, at the Arno river mouth and in a coastal station close to it. The data reported indicates that the Arno river represents an important source of DOC and CDOM to this coastal area, with a total DOC flux of 11.23–12.04·109 g C·y− 1.
Moving from the river to the sea, CDOM absorption and fluorescence decreased, while the spectral slope increased, suggesting a change in the molecular properties of CDOM.
Mineralization experiments were carried out in order to investigate the main processes of DOM removal and/or transformation in riverine and coastal water. DOC removal rates were 20 μM·month− 1 in the river and 3 μM·month− 1 in the seawater, while CDOM was released during the first 30 days and removed in the following 40 days.
Keywords: CDOM, Fluorescence EEM, Absorption spectroscopy, River, Mineralization rate, DOC
