抚河流域氮磷浓度时空分布特征及污染状况评价

Spatiotemporal distribution characteristics of ammonia nitrogen and total phosphorus concentrations in Fuhe River Basin and its pollution assessment

及时掌握抚河流域氮、磷等营养盐浓度时空分布特征,是保障鄱阳湖水环境与水生态安全的关键。基于抚河抚州段干流及主要支流14个国控/省考监测断面近9 a的水质监测数据,研究抚河流域抚州段河流氨氮、总磷浓度的时空分布特征,并利用单因素分析、内梅罗综合污染指数和聚类分析法,对抚河抚州段干支流氨氮、总磷污染状况进行综合评价。结果表明:(1)抚河干流及主要支流断面氨氮、总磷浓度达到Ⅱ类标准比例分别为91.29%和86.19%。(2)抚河流域河流氨氮、总磷浓度年际间变化较小,但年内季节、月际变化较大,氨氮、总磷浓度均在夏季达到最大值。(3)抚河流域上游氨氮、总磷浓度普遍低于中下游地区。(4)抚河干流氨氮、总磷属轻度污染,支流临水、东乡水的氨氮、总磷属重度污染。研究成果对于抚河流域水环境保护和治理具有重要参考价值。

Keeping abreast of the spatiotemporal distribution characteristics of nutrients such as nitrogen and phosphorus in a watershed is the key to ensuring the water environment and aquatic ecological safety of Poyang Lake.Based on the water quality monitoring data of 14 state-controlled/provincial monitoring sites of the main stream and major tributaries of the Fuhe River in the past 9 years,the temporal and spatial distribution characteristics of ammonia nitrogen and total phosphorus concentrations in the Fuhe River Basin were studied.The single-factor evaluation,Nemero composite pollution index and cluster analysis were applied to evaluate the pollution of ammonia nitrogen and total phosphorus content in the main stream and major tributaries of the Fuhe River.Results showed that:(1) Ammonia nitrogen concentrations at 91.29% of the sites and total phosphorus concentrations at 86.19% of the sites were better than Class Ⅱ limit of Environmental Quality Standards for Surface Water.(2) The interannual variations of ammonia nitrogen and total phosphorus concentrations in the Fuhe River were relatively small.However,there were significant monthly and seasonal variations in ammonia nitrogen and total phosphorus concentrations.The maximum values of ammonia nitrogen and total phosphorus concentrations were observed in summer.(3) The concentrations of ammonia nitrogen and total phosphorus in the upstream were generally lower than those in the middle and lower reaches of the Fuhe River.(4) The ammonia nitrogen and total phosphorus in the main stream of the Fuhe River were mildly polluted,and the ammonia nitrogen and total phosphorus in the tributaries of Linshui River and Dongxiang River were severely polluted.The research results have important reference value for the water environment protection and management in the Fuhe River Basin.