Performance of physical and chemical methods in the co-reduction of internal phosphorus and nitrogen loading from the sediment of a black odorous river
Performance of physical and chemical methods in the co-reduction of internal phosphorus and nitrogen loading from the sediment of a black odorous river
复制标题
物理化学方法协同降低黑臭河道沉积物内磷氮负荷的效果
DOI：
10.1016/j.scitotenv.2019.01.326
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发表时间：
2019
影响因子：
9.8
通讯作者：
Tang Wanying
中科院分区：
文献类型：
--
作者：
Yin Hongbin;Wang Jingfu;Zhang Runyu;Tang Wanying
底泥营养盐的持续释放是黑臭河流治理的主要障碍。本研究采用长期的室内培养试验，探讨底泥疏浚、间歇曝气和原位灭活改性粘土对减少严重污染河流底泥内负荷的有效性。结果表明，间歇曝气和原位灭活均能有效降低水体中TN和NH4+浓度。然而，沉积物疏浚并没有一贯减少总氮和NH4+浓度的水柱。相比之下，这三种方法都能有效控制水体中TP和PO43−的浓度。除了疏浚，>30%的NH4+和40%的PO43−通量从沉积物中减少时，与对照样品相比，120天的修复。疏浚引起了显着的释放NH4+从沉积物。疏浚和曝气几乎没有改变沉积物中可提取的氮的量。然而，失活可能会增加沉积物提取铵在深层沉积物层随着时间的推移，由于强烈的生物扰动的粘土垂直运输。疏浚是随着时间推移减少表层移动的磷的最有效方法，而搬运的粘土可以减少深层沉积物中大部分移动的磷。各修复措施均显著提高了表层沉积物中Nitrospira的相对丰度，为减少沉积物中NH4+的释放创造了有利条件.总之，本研究的结果表明，粘土灭活是控制严重污染河流沉积物中磷和氮的内负荷的最佳方法。
The continuous release of nutrients from sediment is a major barrier to the remediation of black odorous rivers. This study used a long-term laboratory incubation experiment to investigate the effectiveness of sediment dredging, intermittent aeration, andin situinactivation with modified clays to reduce the internal loading of sediment from a seriously polluted river. The results indicated that intermittent aeration andin situinactivation were effective in reducing the TN and NH4+concentrations in the water column. However, sediment dredging did not consistently reduce the TN and NH4+concentrations in the water column. In contrast, the three methods were all effective in controlling the TP and PO43−concentrations in the water column. Except for dredging, >30% of NH4+and 40% of PO43−fluxes from sediment were reduced when compared with a control sample after 120 days of remediation. Dredging induced a significant release of NH4+from sediment. Dredging and aeration made nearly no change to the amount of extractable nitrogen in the sediment. However, inactivation may increase sediment-extractable ammonium in deep sediment layers with time due to vertical transportation of clay by intensive bioturbation. Dredging is the most effective way to reduce surface mobile phosphorus over time while the transported clays can reduce a large percentage of the mobile phosphorus in deeper sediment. The relative abundance ofNitrospirain the surface sediment increased significantly with each remediation measure, creating favorable conditions for the reduction of the ammonium released from sediment. Altogether, the results of this study indicated that clay inactivation is the best method for controlling the internal loading of both phosphorus and nitrogen in seriously polluted river sediment.