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通过分析黄河干流溶解铀的沿程变化特征和下游利津站溶解铀浓度的季节性变化,估算了溶解铀的逐月及全年入海通量。研究结果表明,溶解铀浓度从上游至下游总体呈现出沿程逐步增加的趋势,~(234)U/~(238)U放射性活度比在上游源头附近比较高,其余河段~(234)U/~(238)U放射性活度比维持在较稳定的水平(1.3~1.7)。黄河下游利津站溶解铀浓度的变化范围为2.72±0.18μg/L至7.57±0.66μg/L之间,平均值为5.49±0.28μg/L,并且呈现出夏、秋季低于春、冬季的变化规律。黄河下游水沙、溶解铀的月际入海通量年内变化显著,主要集中丰水期特别是调水调沙时期。利津站的径流量是影响溶解铀入海通量的主要因素。2010年、2013和2014年利津站溶解铀的入海通量分别为1.04×10~5kg/a、1.31×10~5kg/a和6.41×10~4kg/a,占世界河流年入海通量的1%左右。
By analyzing the variation of dissolved uranium along the mainstream of the Yellow River and the seasonal variation of dissolved uranium concentration in the lower reaches of Lijin station, the monthly and yearly flux of dissolved uranium into the sea is estimated. The results show that the concentration of U (uranium) uranium increases gradually from upstream to downstream, and the radioactivity ratio of ~ (234) U / ~ (238) U is higher near the upstream of the upstream source. U / ~ (238) U radioactivity maintained at a relatively stable level (1.3 ~ 1.7). The range of dissolved uranium concentrations in Lijin station of the lower Yellow River varied from 2.72 ± 0.18μg / L to 7.57 ± 0.66μg / L with an average value of 5.49 ± 0.28μg / L, and showed a decrease from spring to winter in summer and autumn law. The monthly fluxes of water and sediment and dissolved uranium in the lower Yellow River varied significantly during the year, mainly concentrating on the wet season, especially during the period of water and sediment adjustment. Runoff at Lijin station is a major factor affecting the flux of dissolved uranium into the sea. The fluxes of dissolved uranium entering Lijin station in 2010, 2013 and 2014 were 1.04 × 10 ~ 5kg / a, 1.31 × 10 ~ 5kg / a and 6.41 × 10 ~ 4kg / a respectively, accounting for 1 %about.