赣江南昌段水体尿素时空分布及其来源

Spatial and Temporal Distribution and Sources of Urea in Nanchang Section of Ganjiang River

于2017年1月至2月和6月至7月对赣江南昌段6个采样点进行了水样采样,用二乙酰一肟硫氨脲分光光度法测定了水样中尿素的浓度。结果显示,赣江南昌段上游支流锦江水体中浓度在丰水期尿素(3.2±1.6)μmol/L高于枯水期(1.7±0.8)μmol/L,表明农业尿素肥料是锦江丰水期尿素的主要来源。无论是丰水期还是枯水期,赣江南昌段上游市汊至中游的外洲,尿素浓度呈下降趋势,表明该水段受人为源尿素的影响较小。从外洲至赣江南昌段下游的3条支流中,尿素浓度都呈上升趋势,表明南昌市生活污水排放是赣江南昌段下游水体中尿素的主要来源。

Water samples were collected from six sites in the Nanchang section of Ganjiang River during the low flow season(January and February)and high flow season(June to July),and concentration of urea was analyzed by the spectrophotometric method of diacetyl monoxime coupled with thiosemicarbazide.Results showed that higher concentrations of urea in Jinjiang River located in the upper reach of the Nanchang section during the high flow season than the low flow season,implied fertilizer is the main source of urea during the high flow season.From the upper reach to the middle reach of the Nanchang section of Ganjiang River,the concentration of urea decreased during both the low and high flow season,suggested that less influence of anthropogenic urea to this section.On the contrary,from the middle reach to the lower reach of the Nanchang section of Ganjiang River,the concentration of urea increased during both the low and high flow season,indicated that the municipal wastewater from Nanchang was the dominant source of urea in the lower reach of the Nanchang section of Ganjiang River.