闽江口近岸海域无机氮污染来源分析研究

Study on Sources of Inorganic Nitrogen Pollution in Minjiang Estuary Coastal Waters

2015~2018年《近岸海域环境质量公报》均显示闽江口近岸海域水质状况不容乐观,其中无机氮为主要超标因子之一。通过构建闽江水口电站~闽江外海水环境模型,并对其中参数进行率定验证,计算得到不同区域、不同区县及不同行业的无机氮超标污染权重。结果显示,闽江干流福州区界外区域超标污染权重占比最大,为66.05%;鼓楼区、仓山区超标污染权重占比最高,均为16.76%;在水口电站至闽安区域、闽江口区域未接管的城镇生活污水超标污染权重占比均最高,分别为63.68%、33.47%。根据超标污染权重计算结果,闽江干流福州区界外区域对闽江口近岸海域无机氮污染的贡献最大,其次,在陆域污染源中,未接管的城镇生活污水对无机氮超标的影响最大。因此,应提高对交界断面雄江断面的水质要求,并将污染防治重心放在福州市区,加大对其城镇生活污水所造成的面源污染的控制。

From 2015 to 2018,“Bulletin on environmental quality in coastal waters”shows that the water quality is extremely poor in Minjiang estuary coastal waters,and the inorganic nitrogen is one of the main exceeding standard factors.In this paper,an environmental model of seawater from Shuikou hydropower station of Minjiang River to offshore Minjiang River was established,and the parameters were calibrated and verified.Owing to the model,the excessive pollution weight of inorganic nitrogen in different areas,different districts,and different industries was calculated.The results showed that the weight proportion of excessive pollution in the off-boundary area of Fuzhou,the main stream of Minjiang River,is the largest,66.05%.The Gulou District and the Cangshan District had the highest proportion of excessive pollution,both of which were 16.76%.In shuikou hydropower station to Min'an area and Minjiang Estuary area,the proportion of urban domestic sewage exceeding standard pollution is the highest,which is 63.68% and 33.47% respectively.According to the weight calculation results of excessive pollution,the outer boundary area of the main stream of Minjiang River in Fuzhou has the greatest contribution to the inorganic nitrogen pollution in the coastal waters near the mouth of Minjiang River.Besides,the wastewater of urban life also has the biggest contribution to inorganic nitrogen pollution in Minjiang estuary coastal waters.Therefore,it is necessary to improve the water quality requirements of the Xiongjiang Cross Section,focus on the prevention and control of pollution in Fuzhou urban districts,and strengthen the control of non-point source pollution caused by urban domestic sewage.