Summer hypoxia off the Changjiang Estuary

Abstract

An interdisciplinary survey was carried out off the Changjiang (Yangtze River) Estuary from August 27 to September 2, 2009. Salinity, temperature, dissolved oxygen (DO), and chlorophyll-a were measured with a CTD (SBE 19 plus) multi-sensor system. The characteristics of DO distribution was affected by the Chlorophyll-a in the surface, and was affected mainly by stratification in the water 10m beneath the surface. The minimum DO recorded in this survey was down to 1.02 mg/L. The area, water thickness and AOU (Apparent Oxygen Utilization) of hypoxia zone was 3735 km 2, 23.6m and 0.49×10 6t respectively. Strong relationship between stratification variable (PEAP) and hypoxia is demonstrated. © 2012 Springer-Verlag GmbH.