Analyses (n = 525) of chloride (Cl⁻), bromide (Br⁻), nitrate as nitrogen (NO₃‐N), sodium (Na⁺), calcium (Ca²⁺) and potassium (K⁺) in stream water, tile‐drain water and groundwater were conducted in an urban‐agricultural watershed (10% urban/impervious, 87% agriculture) to explore potential differences in the signature of Cl⁻ originating from an urban source as compared with an agricultural source. Only during winter recharge events did measured Cl⁻ concentrations exceed the 230 mg/L chronic threshold. At base flow, nearly all surface water and tile water samples had Cl⁻ concentrations above the calculated background threshold of 18 mg/L. Mann–Whitney U tests revealed ratios of Cl⁻ to Br⁻ (p = .045), to NO₃‐N (p < .0001), to Ca²⁺ (p < .0001), and to Na⁺ (p < .0001) to be significantly different between urban and agricultural waters. While Cl⁻ ratios indicate that road salt was the dominant source of Cl⁻ in the watershed, potassium chloride fertilizer contributed as an important secondary source. Deicing in watersheds where urban land use is minimal had a profound impact on Cl⁻ dynamics; however, agricultural practices contributed Cl⁻ year‐round, elevating stream base flow Cl⁻ concentrations above the background level.

中文翻译：

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都市农业流域中的氯源描述：除冰剂与农业贡献

分析（Ñ氯化物= 525）（CL ^- ），溴（溴^- ），硝酸氮（NO ₃ -N），钠（Na ⁺），钙（Ca ²⁺），钾（K ⁺在流水） ，瓦漏水和地下水在城市农业分水岭（10％城市/不透水，87％农业）探索Cl组成的签名电位差进行了^-从一个城市源始发与农业源进行比较。只在冬季补给事件并测定氯^-浓度超过230 mg / L的慢性阈值。在基流，几乎所有的地表水和瓷砖水样有氯^-浓度高于计算的本底阈值18 mg / L。曼-惠特尼ù试验揭示的Cl比率^-对溴^- （p = 0.045），为NO ₃ -N（p  <0.0001），与Ca ²⁺（p  <0.0001），并且对Na ⁺（p  < .0001）在城市和农业水域之间存在显着差异。虽然氯^-比率表明道路盐是Cl组成的主要来源^-在分水岭，氯化钾肥料贡献作为重要的次级源。在流域，其中城市土地利用是最小的融雪剂对氯产生了深远的影响^-动力学; 然而，农业实践贡献氯^-全年，提升流基流氯^-浓度高于背景水平。