DOC cycling in a temperate estuary: A mass balance approach using natural 14C and 13C isotopes
Limnol. Oceanogr., 46(3), 2001, 655-667 | DOI: 10.4319/lo.2001.46.3.0655
ABSTRACT: We measured dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and their corresponding del14C and del13C values in order to study the sources and fates of DOC in the York River Estuary (Virginia, U.S.A.). The del14C and del13C values of DOC and DIC at the freshwater end-member indicate that during periods of moderate to high flow, riverine DOC entering the York was composed of decadal-aged terrestrially organic matter. In nearly all cases, DOC concentrations exceeded conservative mixing lines and were therefore indicative of a net DOC input flux from within the estuary that averaged 1.2 mM L-1 d-1.