Abstract The quantification of point source (PS) pollution and non-point source (NPS) pollution in different regions is needed so that targeted management strategies for water environment managers can be prepared. The aim of this study was to establish a method for quantifying PS and NPS pollution by measuring ion concentrations. The Danjiangkou Reservoir and its main tributaries were selected as the study area. The spatiotemporal variation in the concentration of nutrients and ions was analyzed. The results showed that the main ions did not display any distinct spatiotemporal variations on the reservoir, but spatiotemporal variations were evident in the tributaries: Mg2+, Na+, SO42− and Cl− were lowest in the wet season, K+ was highest in the dry-to-wet transition season, and Si was highest in the wet season. We selected Cl−/TN, SO42−/TN, and Na+/TN as PS pollution tracking indicators and K+/TN, Ca2+/TN, and Si/TN as NPS pollution tracking indicators. The mean contribution rate of NPS pollution calculated using Cl−/TN, Na+/TN, and Si/TN, and by the isotope approach, had a significant linear relationship (p

中文翻译：

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水化学特征法在丹江口库区污染源量化中的探索与应用

摘要 需要对不同区域的点源（PS）污染和非点源（NPS）污染进行量化，以便为水环境管理者制定有针对性的管理策略。本研究的目的是建立一种通过测量离子浓度来量化 PS 和 NPS 污染的方法。选择丹江口水库及其主要支流作为研究区。分析了养分和离子浓度的时空变化。结果表明，主离子在储层上没有表现出明显的时空变化，但支流中的时空变化明显：Mg2+、Na+、SO42-和Cl-在雨季最低，K+在旱季最高。向湿季过渡，Si 在雨季最高。我们选择了 Cl-/TN、SO42-/TN、Na+/TN作为PS污染追踪指标，K+/TN、Ca2+/TN、Si/TN作为NPS污染追踪指标。使用 Cl−/TN、Na+/TN 和 Si/TN 计算的 NPS 污染平均贡献率，并通过同位素方法，具有显着的线性关系（p