湖泊疏浚对沉积物-水界面溶解氧的环境效应

Environmental effects of lake dredging on dissolved oxygen at sediment-water interface

水体溶解氧含量是水环境质量的重要参数.本研究将室内模拟实验和疏浚工程相结合,探讨了疏浚对沉积物-水界面耗氧能力、微剖面溶解氧分布的环境效应.研究结果显示,疏浚具有降低溶解氧消耗能力的潜在长期效应,但是由于还原性物质的暴露,疏浚后新生表层沉积物短期耗氧能力很强;疏浚没有改变到氧气在沉积物-水界面中的传质深度.结果暗示疏浚可能显著提高重度富营养化湖泊夏季溶解氧含量.

Dissolved oxygen is a crucial parameter of water quality. This paper combined simulated experiments and a dredging project to study the environmental effects of dredging on oxygen consumption by sediment and vertical distribution of oxygen at sediment-water interface. The results showed that dredging had potential long term effectiveness of decreasing oxygen consump- tion. However, because of reducing substances exposed by dredging, new surface sediments can consume oxygen extensively on short term. Furthermore, the dredging did not change the penetration depth of oxygen. This study suggested that dredging may in- crease summer dissolved oxygen concentration in hyper-eutrophication lake.