滆湖氮污染双同位素溯源与清单统计法对比研究

The Comparation of Dual Isotope and Budget Statistics Method for the Sources of Nitrogen Pollution in Gehu Lake, Jiangsu

滆湖位于我国江苏省,湖区主要涉及常州市的武进区、金坛区以及无锡市的宜兴市。密集的人口和发达的工农业造成滆湖水体中的氮素污染严重,污染来源复杂。因此亟待识别水体中的氮素污染来源,为氮素污染治理提供数据参考。本研究以生活污水、化学肥料及工业废水为硝态氮端元,借助氮氧同位素端元混合模型计算出滆湖区域生活污水、化学肥料及工业废水对滆湖硝态氮污染负荷贡献率,分别为22.79%、33.25%、43.96%。同时本研究针对2013年整年滆湖区域调研数据,利用清单统计法,从宏观上量化了一整年3种来源硝态氮负荷贡献量的绝对值,并推算出相对值,分别为42.09%、48.11%、9.80%。两种方法以互补的方式对不同时间尺度上滆湖硝态氮污染负荷进行了表征,为滆湖硝态氮污染的治理提供了科学参考。

Gehu Lake, which water system consists of Jintan and Wujin districts, Changzhou and Yixing cities, located at Jiangsu Province in East China. The dense population and well-developed industry and agriculture have led to heavy nitrogen pollution with complex nitrogen sources in Gehu Lake. Therefore, it is necessary to distinguish the contributions of each nitrogen source for nitrogen pollution control. In this study, domestic sewage, fertilizer and industrial waste water were employed as nitrogen end members. The end-member mixing model of nitrogen and oxygen isotopes showed that nitrogen contributions from sewage, fertilizer and industrial waste water were 22.79%, 33.25%, and 43.96%, respectively. Meanwhile, the budget analysis on government statistical data and quantified the absolute nitrogen load of different sources in 2013 disclosed that nitrogen contributions were 42.09%, 48.11% and 9.80%, respectively. These two methods characterize nitrogen contributions from sewage, fertilizer and industrial waste water in Gehu Lake at different time scales and provide scientific references for nitrogen pollution remediation.