水深和扰动对北运河沉积物释放的模拟研究

结合汛期河道水位上涨现状，以河流沉积物为研究对象，通过实验室水槽模拟河道的方式，分别在静置和扰动两种工况下，探索汛期降雨导致河道水位上涨对河道沉积物中污染物释放的影响.研究结果表明，在静置条件下，水深正向影响沉积物中COD_Cr的释放通量（R²=0.945），负向影响NH₃-N释放通量（R²=0.967）.在扰动条件下，水深负向影响沉积物中硝酸盐氮的释放通量（R²=0.892），正向影响其他污染物的释放通量.与水位0.3 m相比，水位在0.9 m时，扰动条件下沉积物中COD_Cr、TN、TP以及活性磷的平均释放通量分别提高约150.09%、63.59%、400.84%和352.28%.水位上涨会明显提升沉积物中污染物释放通量，水深对扰动条件下污染物释放更敏感.

Water depth and disturbance impact on pollutants release from sediment in Beiyun River

Combined with the current situation of river water level rising in the flood season, the river sediments were used as the research object, this study explores the effects of pollutant release from the sediment due to river water level fluctuation under the static and disturbance conditions. The results show that water depth positively affects the COD_Cr release flux (R²=0.945) of sediments, and negatively affects NH₃-N release flux (R²=0.967) under static conditions. Under disturbance conditions, water depth negatively affects the release flux (R²=0.892) of nitrate nitrogen in sediments, and positively affects the release flux of other pollutants. Compared with the water level of 0.3 m, when the water level is 0.9 m, the average release fluxes of COD_Cr, TN, TP and active phosphorus in the sediment under disturbance conditions increase by about 150.09%, 63.59%, 400.84% and 352.28%, respectively. Rising water level will significantly increase the flux of pollutants in sediments, and the water depth is more sensitive to the release of pollutants under the disturbance condition.