盐度和水流扰动对河口水体污染物在上覆水-沉积物垂向运移的影响

Impact of salinity and flow disturbance on vertical transport of pollutants in overlying flow-sediment in estuarine water

为保障长江河口地区用水安全以及精准预测水源地水质变化,利用环形水槽装置,开展了盐度和水流扰动对污染物在上覆水-沉积物垂向运移的影响研究。结果表明:水流扰动强度对氨氮因子的垂向运移总体起到促进作用,盐度对氨氮因子垂向运移呈波动抑制作用,其中,水流扰动在盐度对上覆水氨氮浓度的影响机制中起到重要作用;水流扰动对上覆水总磷运移起到促进作用,盐度对总磷运移所起作用呈分段波动关系;水流扰动的增强对沉积底泥吸附总磷起到线性促进作用,但影响较小,盐度对沉积底泥吸附总磷起到先促进后抑制的作用。

In order to ensure the safety of water utilization and accurately predict the change of water quality in water source areas,the impact of salinity and flow disturbance on the vertical transport of pollutants in overlying flow-sediment was studied by using the annular flume device.The results showed that the intensity of flow disturbance played an overall role in promoting the vertical transport coefficient of ammonia nitrogen factor,while the salinity had a fluctuating inhibitory effect on the vertical transport coefficient of ammonia nitrogen factor.Among them,the water flow disturbance played an important role in the mechanism of salinity on the concentration of ammonia nitrogen in overlying water.The flow disturbance improved the concentration of total phosphorus in overlying flow,and salinity had a segmented fluctuation relationship with the transport coefficient of total phosphorus.The increase of flow disturbance linearly and slightly promoted the adsorption of total phosphorus in sedimentary sediments.Nevertheless,the salinity first promoted and then inhibited the adsorption of total phosphorus in sediments.