The sources and sinks (point and non-point) of dissolved organic carbo
n (DOC), particulate organic carbon (POC) and dissolved inorganic carb
on (DIC) are identified for the purposes of simulating carbon flux to
the estuary. The sources and sinks are separated into three categories
: allochthonous; anthropogenic; and autochthonous with each category e
xamined in turn. Carbon loads to the Humber estuary are calculated and
a mass balance calculation is performed for a section of the River Sw
ale in Yorkshire showing decomposition rates of similar to 3.8 t C/ha/
year and a flux of similar to 161 kt C/year. Finally, initial non-poin
t source models are presented for DOG, POC and DIG. These algorithms a
re incorporated into a hydrological model that is used within the LOIS
programme to simulate the flux of carbon to the river. (C) 1998 Elsev
ier Science B.V.