Problem: At the very peak of the spring phytoplankton bloom in the coastal North Pacific, the biomass concentration of phytoplankton remains constant for a few days before starting a rapid decrease. At the moment of the peak, the primary production rate was measured at 54 mmol C/m2/d with the rate representing the primary production integrated over the depth of the photic layer.
Calculate the phytoplankton grazing rate by zooplankton at the peak of the bloom based on the biomass budget (question above). Assume the phytoplankton mortality rate is 50% of the phytoplankton primary production rate.
Show the calculation with correct units in the answer box below. Record your answer to the nearest mmol C/m2/d in the answer box for the following question. Recall that 1 millimol (mmol) = 10-3 mol.