Field observations of oxygen concentration in water column along with the computed saturating oxygen, ammonium concentration, nitrate concentration, phytoplankton biomass, depth of water column, and inflow from rivers for the period July 19, 2004 to July 18, 2005. Region A in the figure represents the active flow period (September 2004 to November 2004). Region B in the figure represents the lean flow period (February 2005 to April 2005).