Oxygen budget for an urban estuary

Abstract

Various processes affecting the dissolved oxygen content of waters of the Norman Creek estuary, Brisbane, were measured or estimated and standardized for the mid tide daylight situation. Over a 9-week period, accrual, aeration and photosynthetic processes resulted in the daily addition of 76,225 and 214 kg oxygen, respectively, and export, deaeration, biochemical oxygen demand, plant respiration and benthic respiration in the daily loss of 30, 89, 91, 97 and 335 kg oxygen, respectively. These processes are highly dynamic, with substantial daily turnover in the water mass. Benthic sediments; enriched with organic matter, exercise a major influence on the dissolved oxygen content of the water.