Managing soil and groundwater resources requires characterization of the hydraulic and chemical transport properties. The determination of such properties on field scales requires conducting extensive numbers of measurements to well represent the spatial distribution and variability of field properties. However, extensive measurements of properties in the field is hampered by the long time-frame required by most of current field procedures.; This study introduces a setup and procedure by which the hydraulic and chemical transport properties can be rapidly estimated at multiple locations. The setup consists of a multiple dripper permeameter, where drippers serve as point sources. The hydraulic properties include saturated hydraulic conductivity (Ks) and macroscopic capillary length (λ c). The hydraulic properties were estimated by measuring a sequence of steady-state water flux densities on the soil surface. The chemical transport properties include immobile water content (&thetas;im), mass exchange coefficient (α) and dispersion coefficient in the mobile domain ( Dm). These chemical transport properties were determined by applying a sequence of conservative tracers into the soil (ST method).; The setup and the procedure were evaluated on six sites on a greenhouse soil pit and tested under actual field conditions with a total of 50 sites. The hydraulic and chemical transport properties were found to be representative when compared with previously reported results for nearby locations and similar soils. A field procedure for determining the chemical transport properties, based on using time domain reflectometry (TDR), was also presented. Breakthrough curves of 38 field locations were obtained from real-time TDR-measurements of soil bulk electrical conductivity. The transport parameters (&thetas; im, α, Dm) from the BTCs were found to be comparable with the parameters produced by the ST-method conducted on the same field location.; The overall results of this study show that the setup and procedure presented here facilitate rapid measurements of surface hydraulic and chemical transport properties at multiple field locations. Such procedures are ideal for management studies that require conducting extensive measurements to better characterize transport processes through the vadose zone.
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机译：管理土壤和地下水资源需要表征水力和化学物质的输送特性。在田间尺度上确定这种性质需要进行大量的测量，以很好地表示田间性质的空间分布和可变性。然而，大多数当前现场程序所需的长时间框架妨碍了对现场属性的大量测量。这项研究介绍了一种设置和程序，通过该程序和程序可以快速估计多个位置的水力和化学传输特性。该设置包括多个滴头渗透仪，其中滴头用作点源。水力特性包括饱和水力传导率（ K s ）和宏观毛细管长度（λ c ）。通过测量土壤表面的稳态水通量密度序列来估算水力特性。化学传递性质包括固定水含量（theta im ），质量交换系数（α）和在移动域中的分散系数（ D m ）。通过将一系列保守的示踪剂施入土壤中（ST方法）来确定这些化学传递性质。在温室土壤坑的六个位置上评估了设置和程序，并在实际田间条件下对总共50个位置进行了测试。与先前报告的附近位置和类似土壤的结果相比，水力和化学物质的输送特性具有代表性。还提出了使用时域反射仪（TDR）来确定化学传输特性的现场程序。从土壤体积电导率的实时TDR测量获得了38个田间位置的突破曲线。发现来自BTC的运输参数（＆ im ，α， D m ）与ST-产生的参数相当在同一野外地点进行的方法。这项研究的总体结果表明，此处介绍的设置和步骤有助于快速测量多个现场位置处的表面水力和化学传输特性。对于需要进行广泛测量以更好地表征通过渗流区的运输过程的管理研究而言，此类程序是理想的选择。
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