官厅水库及上游河道水质时空变化特征分析

Temporal and spatial variation characteristics of water quality in the upstream river of GuantinggReservoir

近年来,京冀携手加大了官厅水库上游流域水源保护力度。为掌握上游水环境保护工作成效,使用长时间序列分析及距平系数方法,研究了2013—2023年官厅水库及上游河道水质的时空变化特征。结果表明:影响官厅水库水质的主要指标为总氮、总磷、高锰酸盐指数、化学需氧量及氟化物。上游来水是库区氮污染物主要来源。汛期入库流量增大时,入库总氮浓度有下降趋势。近年官厅水库及上游河道各水质指标均有不同程度的下降,尤其是在2017年之后,考虑与官厅水库上游采取若干整治措施有关。永定河流域桑干河水质优于洋河;妫水河流域新华营河、古城河水质较好,洋河、桑干河汇合后至永定河库区及妫水河至妫水河库区沿途氮磷元素浓度均逐渐下降,但氟化物及有机污染物指标逐渐升高。综合评判妫水河入库水质优于永定河水质。研究成果为恢复官厅水库饮用水源地功能提供科学依据和决策支持。

In recent years,Beijing and Hebei have jointly strengthened the protection of water sources in the upstream basin of Guanting Reservoir.In order to grasp the effectiveness of the upstream water en-vironmental protection work,this paper uses the method of long time series analysis and anomaly coeffi-cient to study the spatial-temporal variation characteristics of the water quality of Guanting Reservoir and the upstream river from 2013 to 2023.The results show that the main indexes affecting the water quality of Guanting Reservoir are total nitrogen,total phosphorus,permanganate index,chemical oxygen demand and fluoride.Upstream water is the main source of nitrogen pollutants in reservoir area.During flood season,the concentration of total nitrogen in storage tends to decrease with the increase of inflow flow.In recent years,the water quality indexes of Guanting Reservoir and upstream river have declined to varying degrees,especially after 2017,which is considered to be related to the implementation of several remediation measures in the upper reaches of Guanting Reservoir.The water quality of Sanggan River in Yongding River basin is better than that of Yanghe River.The water quality of Xinhuanying River and Gugucheng River in the Guishui River basin is better.The concentrations of nitrogen and phosphorus along the river from Yanghe River and Sanggan River to Yongding River reservoir and from Guishui River to Guishui River reservoir gradually decrease,but the indexes of fluoride and organic pollutants gradually increase.The water quality of Guishui River is better than that of Yongding River.In summary,the ecological restoration of Guanting Reservoir and Yongding River basin has achieved remarkable results.