Oxygen dynamic had been conducted a yearlong investigation to obtain oxygen distribution, oxygen diffusion flux and mineralization rate of organic matter across the new-born interface of bottom water and sediments due to dredge. The results showed that oxygen penetration depth increased with thickening oxidation layer in new-born sediments. Oxygen concentrations decreased rapidly with depth in the sediments, but relatively moderate. Below the penetration depth, the O₂ concentration inside the sediment was under the detection limit (approximation for 0). Oxygen concentration in bottom water in autumn was significantly higher in dredge treatment than those in control, however, there was not statistically significant among the three sampling during the investigation. The diffusive O₂ flux (F_O2) and the oxygen consumption rate (R_O2) were observed based on O₂ microprofiles, otherwise, organic carbon degradation rates (R_org) were obtained from the oxygen consumption rate based on the modified Redfield ratio (O₂/C_org=170/117) and the values also obviously decreased. Therefore, thickening oxidation layer and slowdown organic carbon degradation rates could significantly influence nutrients biogeochemical cycle after dredge.