Undisturbed lysimeters are widely used to study water and solute transport, where both natural and unnatural preferential flow can greatly influence leaching rates. The objective of this study was to use chemical and isotopic tracers to quantify the effect of initial soil water content and lysimeter design on preferential flows. Ten undisturbed lysimeters (900 cm²) were collected from an agricultural field, with the gap between the soil and lysimeter casing sealed with petroleum jelly for five lysimeters. Lysimeters were subjected to two rainfall simulations (3.3 cm h⁻¹) under contrasting initial soil water contents, and leachate near the soil‐casing interface was collected separately from leachate through the bulk soil. Three‐component hydrograph separation revealed that event water comprised 21–59% of total leachate irrespective of initial soil water content and lysimeter design. Sealing the edges of the lysimeters with petroleum jelly greatly reduced but did not eliminate edge flow during rainfall simulations. Although water and solute transport were similar in both sealed and unsealed lysimeters under dry antecedent conditions due to the formation of shrinkage cracks on the soil surface, edge flow was substantially greater for the unsealed lysimeters under wet antecedent conditions. Unsealed edges under wet antecedent conditions facilitated the preferential transport of both event and pre‐event water, resulting in greater solute leaching. Using multiple tracers to contrast lysimeter designs under different initial soil water contents not only allowed for rigorous testing of a commonly used edge‐flow suppression technique but also provided new insights into preferential flow processes and patterns.

中文翻译：

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表面溶质的优先流动：溶渗仪设计和初始土壤含水量的影响

不受干扰的测渗仪广泛用于研究水和溶质的运移，自然和非自然的优先流动都会极大地影响浸出率。这项研究的目的是使用化学和同位素示踪剂来量化初始土壤含水量和溶渗仪设计对优先流量的影响。从农田中收集了十个未扰动的测渗器（900 cm ²），土壤和测渗器套管之间的间隙用凡士林密封了五个测渗器。测力计进行了两次降雨模拟（3.3 cm h ^-1）在初始土壤含水量相反的情况下，靠近土壤-套管界面的渗滤液与渗滤液通过大块土壤分开收集。三分量水位图分离显示，无论初始土壤含水量和溶渗仪的设计如何，事件水都占总渗滤液的21–59％。用凡士林密封测渗仪的边缘大大减少了，但在降雨模拟过程中并没有消除边缘流动。尽管由于土壤表面上形成的收缩裂缝，在干燥的先行条件下密封和未密封的渗漏计中的水和溶质的运移是相似的，但在潮湿的先行条件下，未密封的渗漏计的边缘流动明显更大。湿润的先行条件下未密封的边缘有利于事件水和事件前水的优先运输，导致更大的溶质浸出。使用多个示踪剂对比不同土壤初始含水量下的渗滤仪设计，不仅可以对常用的边流抑制技术进行严格测试，而且还可以为优先流动过程和模式提供新见解。