Carbonate system of the Razdolnaya River estuary (Amur Bay, Sea of Japan)

Two methods, the total alkalinity measurement by Bruevich [4] and pH measurement in a cell without liquid junction [11], were suggested for study of the carbonate system of estuaries. Based on new measurements, the empirical equations were obtained for the first and second seawater concentration constants of carbonic acid for the ranges of salinity 0-40ppt and temperatures 0-30 degree C. Applying the constants and above methods, we studied the carbonate system of the Razdol'naya River-Amur Bay estuary in two expeditions of July 2001, the first in a period of average water level and the second after a flood. In the latter survey, extremely low values ( similar to 60 mu atm) of pCO sub(2) (carbon dioxide partial pressure) were recorded in the seaward part of the estuary and extremely high ( similar to 13 300 mu atm) were noted in the river. High pCO sub(2) in the surface water was caused by intense bacterial activity, and low levels were caused by phytoplankton bloom. The nonconservative behavior of the total alkalinity and dissolved inorganic carbon was revealed in the estuary. Based on the data of the carbonate system, the production/destruction of organic matter was assessed.