Abstract:

Based on the results of in situ incubation experiment in CHINARE-22 cruise (2005.11—2006.3), the degradation process of organic compounds of Prydz Bay was investigated. According to the data of
DO change and nutrient regeneration, the oxygen consumption rate of degradation process and release rate of phosphate, ammonium and silicate were estimated. The results show that the dissolved oxygen in the system decreased linearly with time in the initial stage and, however, gave a nonobvious decrease in the late stage. Contrarily the contents of nutrients increased during the initial stage. The oxygen consumption rate of III-10 was 92.592 mg/m²·h in 100 h, and the release rate of phosphate, ammonium and silicate were 107.15, 65.10, 351.93 μmol/m²·h, respectively. The oxygen consumption rate of IS-2 was 77.927 mg/m²·h in 50 hs, and after 50 h, the rate was reduced to 21.142 mg/m²·h. The release rate of phosphate, ammonium and silicate of IS-2 in the initial 50 h were 43.61, 137.32, 60.89 μmol/m²·h,  respectively.

Key words: organic matter, phytoplankton, degradation, oxygen consumption, Prydz Bay