北京市河流氨氮浓度时空演变特征分析

选取2010—2017年北京市地表水监测数据,对河流氨氮(NH 3-N)浓度的时空演变特征进行分析。结果显示,空间上,全市河流NH 3-N浓度整体上保持上游优于下游的分布特征;年均浓度显著下降,由2010年的8.53 mg/L逐年下降至2017年的3.09 mg/L;河流NH 3-N浓度与化学需氧量、总磷呈显著正相关,与溶解氧显著负相关,总氮与NH 3-N的比值随着水质由差到好呈上升状态。污水收集处理和再生水利用是改善北京市河流水质的关键措施。为持续降低河流NH 3-N浓度,改善首都水环境质量,须提高污水处理能力和出水水质,有机结合再生水回用与生态治水理念。

The Spatial and Temporal Evolution of Ammonia Concentration in Rivers of Beijing

Surface water Monitoring data from 2010 to 2017 were used to analyze the spatial and temporal evolution of ammonia(NH3-N) concentration in rivers of Beijing. Results indicated that rivers in upstream had lower NH3-N concentrations than that in downstream. From 2010 to 2017,the annual average concentration of NH3-N decreased significantly from 8. 53 mg/L to 3. 09 mg/L. Whats more,NH3-N had positive correlation with chemical oxygen demand(COD) and total phosphorus(TP)significantly,while negative correlation with dissolved oxygen(DO). The better condition of water quality,the higher ratio of TN/NH3-N correspondingly. Based on the results of above analysis,wastewater treatment and the reuse of reclaimed water played important roles in water quality improvement. Therefore,in order to continue decreasing NH3-N concentration and improving water quality in Beijing,the total amount of NH3-N emission should be strictly controlled from the aspect of wastewater treatment capacity and effluent quality,and the reclaimed water be reused with ecological method.