ABSTRACT
Gross river flux of dissolved and suspended substances into sea basins is defined as the amount of substances transported by the river to the land/sea boundary. Net river flux is determined as the amount of substances transported across a boundary (GESAMP, 1987). In defining gross and net river flux, it is important to determine the exact boundary between the river and the sea. This boundary is the area where there is no influence of sea water i.e. in a river cross section where flow direction is unilateral. Riverine material entering the zone of river and sea mixing undergoes quantitative and qualitative changes (e.g. sedimentation of suspended matter, aggregation and removal from solution of dissolved and colloidal substances, sorption and desorption). As a result, river material that reaches the open sea is significantly transformed (Gordeev, 1983). Therefore net river flux is the amount of substances which overcomes the geochemical and physical barrier of the river-sea zone and enters the estuary, shelf zone and continental slope, and finally reaches the deep sea.
