曝气充氧对城市污染河道内源铵态氮释放的控制  

The role of aeration in reducing internal NH_4^+-N release from polluted urban river channel

作　　者：凌芬[1] 刘波[1,2] 王国祥[1] 许宽[1] 周锋[1] 杜旭[1] 

机构地区：[1]南京师范大学地理科学学院,南京210046 [2]南通大学地理科学学院,南通226000

出　　处：《湖泊科学》2013年第1期23-30,共8页Journal of Lake Sciences

基　　金：国家自然科学基金项目(41173078);江苏省科技厅科技支撑计划项目(BE2008677);江苏省太湖水环境治理专项基金项目(TH2010303)联合资助

摘　　要：以城市污染河道沉积物和上覆水为研究对象,利用模拟实验方法,探讨不同曝气充氧方式(水曝气EW、底泥曝气ES)对污染河道內源铵态氮(NH4+-N)释放的影响.研究结果发现:从间隙水和沉积物中NH4+-N的削减效果来看,底泥曝气均要优于水曝气;实验结束后,底泥曝气组沉积物与间隙水中NH4+-N含量分别减少63.39%和43.33%,水曝气组分别减少了7.54%和13.98%;从沉积物-水界面NH4+-N的扩散通量变化来看,水曝气组界面通量高于对照组,其变化规律与对照组相似;底泥曝气组沉积物-水界面NH4+-N扩散通量变化过程完全不同于其它两组,在整个试验周期内(除第5 d以外),底泥曝气组的通量低于水曝气组,在第15 d最低,为13.73 mg/(m2.d),仅为水曝气组和对照组的14.68%和19.93%,表明底泥曝气组沉积物NH4+-N的释放潜力低于水曝气组沉积物.To deternfine the NH4＋ -N release from polluted river channel sediments, water and sediment samples were collected. We examined sedimentary NH4＋ -N release under two aeration conditions： aerating to water （EW） and aerating to sediments （ES）. The experimental results showed that the effect of NH4＋ -N removal in ES was higher than that in EW, which removed the NH~ -N both from pore water and sediments. In the ES group, the concentrations of NH4＋ -N in sediment and pore water were decreased by 63.39% and 43.33% , respectively. However, the values of NH4＋ -N in sediments and pore water were merely decreased by 7.54% and 13.98% , respectively, in the EW group. The variation of the diffusion flux of NH4＋ -N was similar between the control group and the EW group across the sediment-water interface, with the value of the EW higher than that of the control group. The diffusion flux of NH4＋ -N in the ES group was completely different from the other two groups. Throughout the trial period（ other than section 5 d）, the value of flux in the ES group was lower than thai in the EW group, and the lowest concentration was showed up in the first 15 d. The value was 13.73 mg/（m2 · d）, which just accounted for 14.68% in the EW group and 19.93% in the con- trol group, respectively. Our results indicated that the NH4＋ -N in the cores of sediment aeration group had a lower release potential than that in the cores of water aeration group.

关 键 词：城市河道 曝气方式 内源 铵态氮释放 

分 类 号：X52[环境科学与工程—环境工程]